Difference between revisions of "Encrypted code: Bilateral Motor Evoked Potentials of trigeminal root"

Latest revision as of 13:13, 12 May 2024

Encrypted code: Bilateral Motor Evoked Potentials of trigeminal root

This detailed summary examines the complex interrelationships between dental malocclusion, postural disorders, and trigeminal neurophysiopathology through the clinical case of a patient known as 'Balancer.' The patient's decade-long suffering from a meningioma at the base of the skull illustrates the challenges and potential misdiagnoses that can occur when traditional dental perspectives are applied without considering deeper neurophysiological issues. The text integrates a broad range of medical insights to argue for a more nuanced approach to diagnosing and treating conditions that straddle neurology and dentistry.

Introduction The chapter opens by highlighting the limitations of axiomatic assumptions in medical diagnoses, particularly in the complex interplay between dental health and neurological conditions. It introduces the case of 'Balancer,' whose symptoms were initially interpreted within a dental framework but later understood to be indicative of significant neurological pathology.

Trigeminal Neurophysiopathology and Misdiagnosis The narrative delves into the specifics of trigeminal neurophysiopathology, explaining how the patient's meningioma exerted physical effects on both sensory and motor fibers of the trigeminal nerve system, leading to severe symptoms that were initially misinterpreted as dental issues. The discussion underscores the importance of considering neurophysiological data in dental diagnoses, particularly when patients present with atypical or severe symptoms that do not align with common dental disorders.

Diagnostic Challenges and Electrophysiological Insights The summary critically evaluates the diagnostic process, emphasizing the role of electrophysiological tests such as the _bRoot-MEPs and assessments of the jaw jerk reflex. These tests revealed the extent of the damage more accurately than dental evaluations and highlighted the need for medical imaging to confirm the presence and impact of the meningioma.

MRI Findings and Neurological Complications MRI results confirmed the severe implications of the meningioma, showing brainstem displacement and raising urgent questions about the initial stages of the tumor's development. This section reflects on whether earlier detection of the tumor through targeted electrophysiological testing could have altered the patient's treatment trajectory.

Misleading Symptoms and the Importance of Accurate Diagnosis The patient's case is used to illustrate how symptoms like 'chewing difficulty' can be misleading. The narrative argues for a more integrated diagnostic approach that combines dental and neurological expertise to avoid oversimplified conclusions that may lead to inadequate treatments.

Cognitive Neural Network (CNN) Diagnostic Model The use of a Cognitive Neural Network (CNN) in diagnosing 'Balancer's' condition is discussed, showcasing how advanced data analysis techniques can aid in distinguishing between symptoms related to dental malocclusions and those stemming from serious neurological conditions. This section details the sequential steps taken through the CNN to refine the diagnosis and better understand the underlying causes of the patient's symptoms.

Clinical Implications and Future Directions The chapter concludes by discussing the broader clinical implications of the case for both dentistry and neurology. It calls for heightened awareness of the potential for neurological conditions to manifest through symptoms typically associated with dental issues and recommends more interdisciplinary approaches in medical training and practice to prevent similar diagnostic errors.

Summary

This summary not only provides a detailed recount of 'Balancer's' medical journey but also serves as a cautionary tale about the risks of compartmentalized medical thinking. It advocates for a holistic approach to patient care that respects the complex interconnections between different bodily systems and emphasizes the critical importance of accurate, comprehensive diagnostic practices in ensuring effective treatment outcomes.

Contents

1 Keywords

1.1 Introduction

1.2 Diagnostic sequence

1.2.1 1st Step: CNN Sequence

1.2.1.1 2st Step: CNN analysis

1.3 Decryption process

1.3.1 Encrypted code

1.3.1.1 Motor evoked potentials of the trigeminal root

1.4 Final considerations

1.5 Conclusion

1.6 Appendix

Keywords

Trigeminal Neurophysiopathology - Refers to the study of diseases that affect the trigeminal nerve, highlighting the nerve's role in conveying sensory information from the face to the brain. This term is crucial for medical content discussing neurological impacts on facial sensation and motor functions.
Dental Malocclusion - Describes the misalignment of teeth and how they fit together when the jaws are closed. This keyword is key for dental health content, focusing on how teeth alignment affects overall oral health and potentially other bodily functions.
Postural Disorders - Pertains to conditions that affect the posture or the way the body is positioned when standing or sitting. This term is particularly relevant in discussions about how spinal and muscular health can be influenced by neurological and dental health.
Meningioma - A type of brain tumor that forms from the meninges, the layers of tissue covering the brain and spinal cord. This keyword is critical for content on brain tumors, discussing symptoms, diagnosis, and treatment options.
Electrophysiological Tests - Refers to diagnostic tests that measure electrical activity in the body, such as nerve impulses. These tests are crucial in neurology content, especially in diagnosing and understanding the extent of nerve damage.
Jaw Jerk Reflex - A reflex that helps diagnose disorders of the trigeminal nerve by tapping the jaw and observing the response. This keyword is relevant for neurological examination content, focusing on reflex testing.
Cognitive Neural Network (CNN) in Diagnosis - Discusses the application of advanced data analysis techniques in medical diagnostics, especially for integrating and analyzing patient data for better diagnostic accuracy. This term is significant for content on medical technology and innovations in diagnostics.
MRI Findings in Neurology - MRI (Magnetic Resonance Imaging) findings that provide insights into brain and nerve conditions, essential for content related to medical imaging techniques and their applications in diagnosing neurological disorders.
Motor Evoked Potentials (MEPs) - A diagnostic measure of the electrical activity in response to stimulation of the motor cortex, used to assess the functionality of motor pathways, particularly relevant for neurophysiological testing content.

Neurological and Dental Integration - Focuses on the interdisciplinary approach between neurology and dentistry to tackle complex cases that exhibit symptoms affecting both the neurological and dental systems, crucial for content on comprehensive patient care and diagnostic strategies.

Article by Gianni Frisardi · Giorgio Cruccu · Flavio Frisardi

Introduction

In the introductory chapter concerning the 3rd clinical case affected by meningioma in which the masticatory difficulty reported by the patient 'Balancer' had been correlated to a prosthetic rehabilitation discrepancy, we have already arrived at a first diagnostic filter considering the neurological assertion to be valid than the dental one. Consequently, one can concentrate on intercepting the tests necessary to decrypt the machine language code that the CNS sends out converted into verbal language. Apparently this verbal language would address the case in a Postural disorder related to a dental malocclusion due to incongruous prosthetic rehabilitation. If, on the one hand, there may be an asymmetry of the interferential EMG of the masseters due to a prosthetic occlusal imbalance, on the other, such an evident asymmetry of the jaw jerk and the silent period cannot be justified. For this reason, it is essential to continue with the Masticationpedia diagnostic model in order to arrive at an exact and rapid conclusive diagnosis. We therefore begin with the 'Cognitive Neural Network' which responds, as we know by now, with a sequence of scientific-clinical data, always taking into consideration the importance of the 'initiation' step which in this case has been set in 'Gait'.

$CNN=\sum ($ Gait (45.300), motor evoked potentials (231),reflex (36), jaw(1) $\longrightarrow$ 'Cerebellar ataxia, neuropathy, vestibular areflexia syndrome (CANVAS) with chronic cough and preserved muscle stretch reflexes: evidence for selective sparing of afferent Ia fibres'

Diagnostic sequence

1st Step: CNN Sequence

$\tau$ Coherence Demarcator: As we have previously described for the other clinical cases, the first step is an initialization command of the Cognitive Neural Network 'CNN' which derives, in fact, from a previous cognitive elaboration on the assertions in the dental and neurological context in which the ' Demarcator of Consistency' gave a prevailing weight. The dental context has already been eliminated from the Consistency Demarcator. From what emerges from the neurological statements, the 'State' of the Trigeminal Nervous System' appears to be strongly damaged. The initialization command will therefore be 'Gait'.

1st loop open: The first result of the 'CNN' for the keyword 'Gait' returns 45,300 results, obviously, too vast to be exhaustive but having ascertained in the context analysis phase a serious trigeminal electrophysiological situation with marked structural anomalies and functional, we can safely enter a correlated key such as ' Motor Evoked Potentials' without specifying the trigeminal district which could encroach on the identified set.

2st loop open: To this second query 'Motor Evoked Potentials' the database replies with 231 results that are still too vast as an answer and therefore we are looking for a key more similar to the clinical case presented. Since the most anomalous results in the neurological context have emerged from the latency and amplitude alterations of the trigeminal reflexes, an appropriate access key could be, in fact, 'Reflex' also without specifying 'trigeminal' for the same anticipated reasons.

3st loop open: To the 'Reflex'request, the response was 36 results which narrowed the field of analysis for the diagnosis of our patient 'Balancer'. Only at this level of the CNN can one attempt to close the loop with a more specific request such as 'Jaw'. In this way we have not lost contact with the whole considered and we have remained in the field of electrophysiology.

4st loop open: The request 'jaw' in fact in the 36 results it is possible to intercept an article in which some electrophysiological parameters are reported which correspond to a clinical situation of cerebellar ataxia, a pathology in which postural and gait instability is a clinical sign impressive and important.

2st Step: CNN analysis

The 'CNN' loop closure analy of course is based on the terminal article which basically describe five patients with cerebellar ataxia, neuropathy and vestibular areflexia syndrome (CANVAS) with chronic cough and lower limb muscle stretch reflexes preserve yourself.^[1] In particular, somatosensory evoked potentials were absent or severely attenuated. Biceps and hamstring T-reflex recordings were normal, while the masseter reflex was absent or attenuated.

Figure 1: Neurological statement highlighting a severe right jaw jerk latency and amplitude abnormality
The first observation to be made is that the patients were suffering from chronic spasmodic cough and the second observation was the preservation of the tendon reflexes of the lower limbs. In our patient 'Balancer', on the other hand, there was a total absence of the mandibular tendon reflex^[2] ( $\gamma _{1}$ ) so that the neurological damage was very evident at the trigeminal midbrain level. (Figure 1) The multifunctional contribution of the midbrain synaptic circuitry by the proprioceptive nerve endings ( $1a$ e $\gamma$ ) are of primary importance both for posture and for cervico-oculomotor reflexes. A very interesting article by Yongmei Chen et al.^[3] showed, through markers, how neurons afferent to the trigeminal mesencephalic nucleus (Vme) from the jaw muscles project to the oculomotor nuclei (III/IV) and their premotor neurons in the interstitial nucleus of Cajal (INC), a well-known pre-oculomotor center that vertically manipulates torsional eye movements.
The conceptual conclusion of the authors was that the Vme proprioceptive neurons of the masticatory projecting muscles at III/IV and INC would detect spindle activity to spatial changes of the jaw conditioned by the force of gravity and/or by the connection between the mandible during rotation of the head. Thus, the convergent innervation of Vme and MVN neurons on the oculomotor and pre-oculomotor nuclei would be a neuroanatomical substrate for the interaction of masticatory proprioception with vestibulo-ocular signals on the oculomotor system during vertical-torsional VOR. The contribution of this article obviously allows us to consider a correlation between the trigeminal system, posture and gait, therefore, the abnormal asymmetry of the jaw jerk could be related to a postural disorder of our patient 'Balancer'

But there is also to consider the article of Jon Infante ^[1] highlighted that all five patients were in the seventh decade of age, their gait imbalance having started in the fifth decade. In four patients, cough preceded gait imbalance between 15 and 29 years of age; the cough was spasmodic and triggered by variable factors. In addition, vestibular function tests showed bilateral impairment of the vestibulo-ocular reflex.

Figure 2: Occlusal aspect of the 'Balancer' patient who had the occlusal incongruity on the right side restored several times.
The presence of chronic spasmodic cough, in this study, for over 10 years even before balance and postural disturbances showed up, suggest that machine language, as repeatedly exposed in the specific chapters of Masticationpedia, is a reality not to be overlooked because the ambiguous and vague verbal language covers the information of the encrypted code. As we will demonstrate in the course of the discussion, the analog of the spasmodic cough symptom of the patients reported by Jon Infante's article could be the repeated reporting to the dental colleagues of the chewing difficulty by our patient 'Balancer'. (Figure 2) This parameter has not been considered as an 'encrypted code' but only an element of verbal language logic and therefore vague and ambiguous. The continuous remaking of the prosthetic rehabilitation dampened even more the information of the machine language until the temporal and spatial addition of the organic damage was transformed^[1] into a macroscopic symptom of vertigo and loss of balance in walking

Jon Infante's article^[1] concludes with a striking statement, i.e. that spasmodic cough can be an integral part of the clinical picture in CANVAS, anticipating the appearance of postural imbalance by several decades and that sparing of muscle spindle afferents (Ia fibers) is probably the pathophysiological basis of normoreflexia.

«We came to the conclusion that the patient's postural disorder could not be related to the rehabilitative occlusal incongruity but to a neurological damage but the question now is the following:»
(........is the neurological damage functional or organic?)

Decryption process

The diagnostic procedure followed routinely according to the Masticationpedia model has allowed us to eliminate, through the coherence demarcator, the dental context to follow the neurological one and to deepen through the 'Cognitive Neural Network' (CNN) the possible correlations between symptoms and neurophysiological abnormalities in patients with postural and walking disorders due to functional pathologies (labyrinthitis, neuropathies, etc.) from organic ones (tumors, demyelinations, etc.). Now we must try to decrypt the encrypted message of the machine language of the Trigeminal Nervous System.

Encrypted code

Figure 2: Determination of the functional component of the Central Nervous System. The results for patient 2 (normocclusion) show an area of 1.37 mV/ms and 0.13 mV/ms on the right and left masseter, respectively. This shows an asymmetry between sides of about 100%.

Figure 1: Neurological statments

\gamma _{1}

highlighting severe jaw jerk latency abnormality

As anticipated, first of all we were able to highlight a serious absence of the jaw jerk reported as $\gamma _{1}=1\longrightarrow$ Abnormality, positive report (Figure 1) but as already mentioned in the chapter

' Conclusions on the status quo in the logic of medical language regarding the masticatory system' also in the patient treated with orthognathic surgery we were able to detect an absence of the jaw jerk (figure 2) restored immediately after evoked neurognathological rehabilitation. In our case 'Balancer' we have an additional objective disorder that of masticatory difficulty and together with the postural disorder there were nystagmus and vertigo.

A further assertion in favor of organic damage was also the presence of a latency delay on the right side of the electrical silent period, $\gamma _{3}=1\longrightarrow$ Abnormality, positivity of the report, which suggests a slowing of the nerve conduction speed. In this instance we cannot say whether the delay refers to damage to the sensory or motor fibers until we approach the study of the nerve conduction of the motor trigeminal roots.

Motor evoked potentials of the trigeminal root

Figure 4: MRI report of meningioma in right skull base

Figure 3: Bilateral transcranial electrical stimulation evoked responses. A marked asymmetry of amplitude in the right Masseter is evident.

In our masticatory neurophysiology laboratory we have developed a technique of electrical transcranial electrostimulation of the two trigeminal roots simultaneously and synchronized with the electrical stimulus. In the various chapters already published some technical information on the method is reported but we intend to expose them exhaustively in the section 'Extraordinary science'. In this context we can only consider and confirm a significant amplitude asymmetry of the motor evoked responses as shown in figure 3. The markers 1A and 2A indicate the latency which, unlike the silent period, is symmetrical and this data confirms the structural damage of the sensory fibers including those proprioceptive from masticatory muscles. At this point we can not only confirm and justify the neurological choice of the diagnostic context but also conclude with a pre-diagnosis of cerebellar neurological damage with involvement of the trigeminal mesencephalic axis.

The Magnetic Resonance of the brain, unfortunately, solves our doubts with a report of solid expansive lesion with mass effect in the right hemisphere, it is not clear whether it has a supra or sub tentorial origin, it certainly determines compressive phenomena on the midbrain - trunk and on the fourth ventricle with dilatation of the cisternae and ventricles upstream. That it is a meningioma is very likely because he has no perilesional edema.

Final considerations

We summarize the clinical diagnostic path following the Masticationpedia model so that the latter can be considered a fluid and dynamic process to reach a diagnostic target in the fastest and most detailed way.

Context analysis through dental and neurological laboratory tests
Choice of neurological statement filtered by the $\tau$ Coherence Demarcator
Evaluation of the clinical case in the Cognitive Neural Network (CNN)
Closing the CNN loop with Jon Infante's article^[1] and the consideration of the organic/functional damage of our patient's trigeminal sensory-motor structures through the observation of the amplitude asymmetry of the 'bRoot-MEPs'. The logical sequence of the tests carried out with the numbering restored has been ordered in the image gallery.

Figure 1a: The first test that must always be performed in complex clinical cases is, in fact, the _bRoot-MEPs
Figure 1b: The second test is the jaw jerk which returns a sort of analysis of the integrity of the midbrain system. In our case 'Balancer' an abnormal asymmetry is evident to the detriment of the right masseter
Figure 1c: After verifying the level of integrity of the midbrain area through tests involving monosynaptic reflexes such as jaw jerk, the level of complexity is raised by evoking the electrical silent period which is a polysynaptic reflex. The latency delay on the right masseter is evident
Figure 1d: Obviously after these results, the patient cannot be considered affected by postural disorder but by organic neurological pathology and the Nuclear Magnetic Resonance of the brain shows it in all its diagnostic potential.

Conclusion

We now have evidence of both direct and indirect functional organic correlation between the trigeminal system and the vestibular system, just think of the study of mVEMP (Vestibular Evoked Myogenic Potentials) now recognized as a solid and reliable test for assessing the functional integrity of the reflex pathway vestibulo-masseteric^[4] in clinical manifestations with involvement of the trigeminal and vestibular system as in schwannomas^[5]^[6] or in the presence of acoustic neuromas^[7] as much as the relative correlation between dental occlusion and the vestibular system but this does not allow, given the seriousness of the diagnostic error that it would result, to consider this last clinical condition a clinically validated scientific datum. In the Appendix an example of what might happen.

This last assertion, perhaps risky because it is controversial, collides with the evidence of a striking fact highlighted several times during the drafting of the chapters of Masticationpedia, that of machine language and verbal language. A vague and ambiguous verbal language can generate scientific convictions depending on how it is proposed but in substance it covers and hides a much more decisive and formal machine language. For example, the verbal language deduced that the postural disturbances of the 'Balancer' patient were caused by an incongruous prosthetic rehabilitation while the machine language signaled an organic sensorineural deficit (absence of the jaw jerk, latency delays of the silent period, large reduction in the amplitude of the _bRoot-MEPs.

The lack of information on the velocity and the mandibular position at the midbrain level, in fact, determines an incapacity of stereognostic awareness in which the patient does not recognize the spatial and temporal position of the mandible. The decrease in the recruitment of the motor units of the masticatory muscles and not only of the tested masseter with an obvious decrease in the masticatory force is the result of this organic and functional damage. All this indicates an impairment of the proprioceptive territory but we do not know if the sensory structures have also been involved. The electrical silent period, on the other hand, shows a severe delay in latency with a slowing of nerve conduction velocity. To conclude the neurophysiopathological diagnostic picture is the observation that the right trigeminal motor root has lost most of its motor fibers.

However, it should be noted that in such a serious clinical condition we see a decrease in the amplitude of the _bRoot-MEPs but not a latency asymmetry. This finding indicates that there was direct damage to the trigeminal motor fibers from tumor compression (axonotmesis) but not demyelination (neuropraxia) which would have shown latency delay on the right masseter. It is advisable to briefly describe the definition of neurological damage bearing in mind that the equivalent of the spinal peripheral nerve for the trigeminal nervous system corresponds to the motor trigeminal root.

Neurotmesis is caused by a transection of a nerve and is the worst degree of peripheral nerve injury. In neurotmesis, the entire nerve, including the endoneurium, perineurium, and epineurium, is completely severed. Neurotmesis leads to disruption of the axon, myelin sheath, and connective tissues. The prognosis for spontaneous recovery is poor without surgery.^[8] Sunderland's fifth-degree lesion fits the definition of neurotmesis in the Seddon classification and represents the highest degree of nerve injury, with a complete nerve defect.

Neurapraxia is a nerve injury commonly induced by focal demyelination and/or ischemia and is the mildest type of peripheral nerve injury. In neurapraxia, nerve impulse conduction is blocked in the injured area, sensory and motor connection is lost, but all morphologic structures of the nerve stump, including the endoneurium, perineurium, and epineurium, remain intact.

Axonotmesis is a relatively more serious type of peripheral nerve injury and is usually caused by crushing, stretching, or percussion. In axonotmesis, the epineurium is intact, while the perineurium and endoneurium may be disrupted. The axon is separated from the soma and the axon and myelin sheath are disrupted. Wallerian degeneration occurs in the axon stump distal to the injury site within 24 to 36 hours after peripheral nerve injury.

After neurotmesis, Schwann cells respond adaptively to axonal disruption, transitioning from a highly myelinated state to a dedifferentiated state. De-differentiated Schwann cells engulf axons and myelin debris and form a regenerative pathway for axon outgrowth. Additionally, activated Schwann cells secrete a group of cytokines, including tumor necrosis factor-alpha, interleukin-1 alpha, and leukemia inhibitory factor, to recruit macrophages and facilitate digestion of debris. Schwann cells also secrete a group of neurotrophic factors, including nerve growth factor, brain-derived neurotrophic factor, and glial cell line-derived neurotrophic factor, to encourage neuron survival and axon elongation.^[9]^[10]^[11]

Needle electromyography (EMG) is the most sensitive electrodiagnostic study for motor axon loss, and low-amplitude motor responses appear with severe injuries. Decrease in motor response amplitude begins around days 2-3 and is complete by day 6. This reflects the fact that neuromuscular junction degeneration precedes axon degeneration and motor responses are dependent on neuromuscular junction transmission.^[12]

Appendix

Patient treated by a dental colleague for a prosthetic rehabilitation following postural methods which indicated the best Centric occlusion through dynamometric platforms. The patient came to our observation presenting a clinical state of fasciculation of the masseter muscles as well as, obviously, an occlusal and masticatory discomfort. The centric position finalized by the colleague was, therefore, correlated with the best postural dynamometry response but unfortunately this did not result.

Observing figures 5,6 and 7 we can understand how axioms are built that do not respond to a validated scientific criterion, much less to a biological reality. Thinking that a remote phenomenon such as postural stability dictated by a dynamometric platform can validate the choice of a position occlusal achieved manually by the operator breaks down on the observation that by observing the state of the trigeminal system by measuring it through a demand (_bRoot-MEPs) the system responds with its own spatial position not dictated by posturological correlation nor by the manual maneuvers of the operator but by its own vectorial neuromotor result.

Figure 5: Rehabilitated patient following posturological indications from dynamometry data.
Figure 6: Centric occlusion defined through data indications of the dynamometric platform.
Figure 7: Centric position resulting from bRoot-MEPs. Note the retrusion of at least 3mm and the leftward displacement of the mandible.

«In conclusion, the correlation between the vestibular and trigeminal systems, although present from a neurophysiopathological point of view, should not be considered a clinical procedure in masticatory rehabilitation.»
(….should only be considered as an experimental exploratory field to deduce more knowledge on neuronal connectivity.)

Bibliography & references

↑ ^1.0 ^1.1 ^1.2 ^1.3 ^1.4 Jon Infante, Antonio García, Karla M Serrano-Cárdenas, Rocío González-Aguado, José Gazulla, Enrique M de Lucas, José Berciano. Cerebellar ataxia, neuropathy, vestibular areflexia syndrome (CANVAS) with chronic cough and preserved muscle stretch reflexes: evidence for selective sparing of afferent Ia fibres.J Neurol . 2018 Jun;265(6):1454-1462. doi: 10.1007/s00415-018-8872-1.Epub 2018 Apr 25.
↑ The history of examination of reflexes. Boes CJ.J Neurol. 2014 Dec;261(12):2264-74. doi: 10.1007/s00415-014-7326-7. Epub 2014 Apr 3.PMID: 24695995
↑ Chen Y, Gong X, Ibrahim SIA, Liang H, Zhang J.. Convergent innervations of mesencephalic trigeminal and vestibular nuclei neurons onto oculomotor and pre-oculomotor neurons-Tract tracing and triple labeling in rats. PLoS One. 2022 Nov 28;17(11):e0278205. doi: 10.1371/journal.pone.0278205. eCollection 2022.PMID: 36441755
↑ Sangu Srinivasan Vignesh, Niraj Kumar Singh, Krishna Rajalakshmi. Tone Burst Masseter Vestibular Evoked Myogenic Potentials: Normative Values and Test-Retest Reliability. J Am Acad Audiol. 2021 May;32(5):308-314. doi: 10.1055/s-0041-1728718.Epub 2021 Jun 1.
↑ Ashutosh Kumar, Sanjay Behari, Jayesh Sardhara, Prabhaker Mishra, Vivek Singh, Vandan Raiyani, Kamlesh Singh Bhaisora, Arun Kumar Srivastava . Quantitative assessment of brainstem distortion in vestibular schwannoma and its implication in occurrence of hydrocephalus.Br J Neurosurg . 2022 Dec;36(6):686-692. doi: 10.1080/02688697.2022.2047155.Epub 2022 Mar 7.
↑ Daniel Moualed, Jonathan Wong, Owen Thomas, Calvin Heal, Rukhtam Saqib, Cameron Choi, Simon Lloyd, Scott Rutherford, Emma Stapleton, Charlotte Hammerbeck-Ward, Omar Pathmanaban, Roger Laitt, Miriam Smith, Andrew Wallace, Mark Kellett, Gareth Evans, Andrew King, Simon Freeman. Prevalence and natural history of schwannomas in neurofibromatosis type 2 (NF2): the influence of pathogenic variants. Eur J Hum Genet. 2022 Apr;30(4):458-464. doi: 10.1038/s41431-021-01029-y.Epub 2022 Jan 24.
↑ Claudia Cassandro, Roberto Albera, Luca Debiasi, Andrea Albera, Ettore Cassandro, Alfonso Scarpa, Massimo Ralli. What factors influence treatment decision making in acoustic neuroma? Our experience on 103 cases. Int Tinnitus J. 2020 Nov 18;24(1):21-25.doi: 10.5935/0946-5448.20200004.
↑ Kaya Y, Sarikcioglu L. Sir Herbert Seddon (1903-1977) and his classification scheme for peripheral nerve injury. Childs Nerv Syst. 2015 Feb;31(2):177-80.
↑ Jessen KR, Mirsky R, Lloyd AC. Schwann Cells: Development and Role in Nerve Repair. Cold Spring Harb Perspect Biol. 2015 May 08;7(7):a020487.
↑ Madduri S, Gander B. Schwann cell delivery of neurotrophic factors for peripheral nerve regeneration. J Peripher Nerv Syst. 2010 Jun;15(2):93-103.
↑ Yi S, Zhang Y, Gu X, Huang L, Zhang K, Qian T, Gu X. Application of stem cells in peripheral nerve regeneration. Burns Trauma. 2020;8:tkaa002
↑ Ferrante MA. The Assessment and Management of Peripheral Nerve Trauma. Curr Treat Options Neurol. 2018 Jun 01;20(7):25.

[:0-1] 1.0 ^1.1 ^1.2 ^1.3 ^1.4 Jon Infante, Antonio García, Karla M Serrano-Cárdenas, Rocío González-Aguado, José Gazulla, Enrique M de Lucas, José Berciano. Cerebellar ataxia, neuropathy, vestibular areflexia syndrome (CANVAS) with chronic cough and preserved muscle stretch reflexes: evidence for selective sparing of afferent Ia fibres.J Neurol . 2018 Jun;265(6):1454-1462. doi: 10.1007/s00415-018-8872-1.Epub 2018 Apr 25.

[2] The history of examination of reflexes. Boes CJ.J Neurol. 2014 Dec;261(12):2264-74. doi: 10.1007/s00415-014-7326-7. Epub 2014 Apr 3.PMID: 24695995

[3] Chen Y, Gong X, Ibrahim SIA, Liang H, Zhang J.. Convergent innervations of mesencephalic trigeminal and vestibular nuclei neurons onto oculomotor and pre-oculomotor neurons-Tract tracing and triple labeling in rats. PLoS One. 2022 Nov 28;17(11):e0278205. doi: 10.1371/journal.pone.0278205. eCollection 2022.PMID: 36441755

[4] Sangu Srinivasan Vignesh, Niraj Kumar Singh, Krishna Rajalakshmi. Tone Burst Masseter Vestibular Evoked Myogenic Potentials: Normative Values and Test-Retest Reliability. J Am Acad Audiol. 2021 May;32(5):308-314. doi: 10.1055/s-0041-1728718.Epub 2021 Jun 1.

[5] Ashutosh Kumar, Sanjay Behari, Jayesh Sardhara, Prabhaker Mishra, Vivek Singh, Vandan Raiyani, Kamlesh Singh Bhaisora, Arun Kumar Srivastava . Quantitative assessment of brainstem distortion in vestibular schwannoma and its implication in occurrence of hydrocephalus.Br J Neurosurg . 2022 Dec;36(6):686-692. doi: 10.1080/02688697.2022.2047155.Epub 2022 Mar 7.

[6] Daniel Moualed, Jonathan Wong, Owen Thomas, Calvin Heal, Rukhtam Saqib, Cameron Choi, Simon Lloyd, Scott Rutherford, Emma Stapleton, Charlotte Hammerbeck-Ward, Omar Pathmanaban, Roger Laitt, Miriam Smith, Andrew Wallace, Mark Kellett, Gareth Evans, Andrew King, Simon Freeman. Prevalence and natural history of schwannomas in neurofibromatosis type 2 (NF2): the influence of pathogenic variants. Eur J Hum Genet. 2022 Apr;30(4):458-464. doi: 10.1038/s41431-021-01029-y.Epub 2022 Jan 24.

[7] Claudia Cassandro, Roberto Albera, Luca Debiasi, Andrea Albera, Ettore Cassandro, Alfonso Scarpa, Massimo Ralli. What factors influence treatment decision making in acoustic neuroma? Our experience on 103 cases. Int Tinnitus J. 2020 Nov 18;24(1):21-25.doi: 10.5935/0946-5448.20200004.

[8] Kaya Y, Sarikcioglu L. Sir Herbert Seddon (1903-1977) and his classification scheme for peripheral nerve injury. Childs Nerv Syst. 2015 Feb;31(2):177-80.

[9] Jessen KR, Mirsky R, Lloyd AC. Schwann Cells: Development and Role in Nerve Repair. Cold Spring Harb Perspect Biol. 2015 May 08;7(7):a020487.

[10] Madduri S, Gander B. Schwann cell delivery of neurotrophic factors for peripheral nerve regeneration. J Peripher Nerv Syst. 2010 Jun;15(2):93-103.

[11] Yi S, Zhang Y, Gu X, Huang L, Zhang K, Qian T, Gu X. Application of stem cells in peripheral nerve regeneration. Burns Trauma. 2020;8:tkaa002

[12] Ferrante MA. The Assessment and Management of Peripheral Nerve Trauma. Curr Treat Options Neurol. 2018 Jun 01;20(7):25.

[1]

[2]

[3]

[4]

[5]

[6]

[7]

[8]

[9]

[10]

[11]

[12]

@@ Line 1: / Line 1: @@
+{{main menu}}
-{{Versions
- | en = Encrypted code: Bilateral Motor Evoked Potentials of trigeminal root
- | it = Codice criptato: Potenziali Evocati Motori Bilaterali della radice trigeminale
- | fr = 'Code crypté : Potentiels évoqués moteurs bilatéraux de la racine du trijumeau'
- | de = 'Verschlüsselter Code: Bilaterale motorisch evozierte Potenziale der Trigeminuswurzel'
- | es = 'Código cifrado: Potenciales evocados motores bilaterales de la raíz del trigémino'
- | pt = <!-- portoghese -->
- | ru = <!-- russo -->
- | pl = <!-- polacco -->
- | fi = <!-- finlandese/suomi -->
- | ca = <!-- catalano -->
- | ja = <!-- giapponese -->
- }}
 [[File:Meningioma 3 by Gianni Frisardi.jpeg|link=link=Special:FilePath/Meningioma_3_by_Gianni_Frisardi.jpg|alt=|left|frameless]]
-In questo ultimo capitolo riferito alla correlazione tra malocclusione e disturbi posturali possiamo percepire come gli assiomi a volte frettolosamente generati da una conoscenza di base limitata nel campo della neurofisiopatologia trigeminale possano provocare danni gravi da un punto di vista diagnostico. Il paziente 'Balancer' presentato nei capitoli precedenti da più di 10 anni era affetto da un meningioma in base cranica che per il suo volume in crescita progressiva ha compresso e contestualmente stirato le fibre sensitive e motorie del sistema trigeminale oltre aver danneggiato i centri mesencefali e pontini e le aree adiacenti al tumore. Il termine usato dal paziente nel riferire il disturbo,  in linguaggio verbale, era 'difficoltà masticatoria' ma in linguaggio macchina si sarebbe dovuto decriptare in 'mancanza dell'effetto stereognosico masticatori' da deficit sensoriale propriocettivo. L'assenza del jaw jerk sul lato destro, infatti, ne dimostra la reale entità del danno. La <sub>b</sub>Root-MEPs conferma il danno organico e la asimmetria di latenza del periodo silente elettrico conclude la diagnosi clinica. La RMN mostra la grave complicazione neurologica di spostamento del tronco encefalico. Si tenga conto che un meningioma di questa entità aumenta di volume fino a raggiungere, come ne nostro caso un diametro di 8 cm, con una latenza temporale decennale. La domanda è la seguente: nelle prime fasi dell'incremento volumetrico dove erano apprezzabili esclusivamente disturbi di tipo masticatorio riferito ai colleghi odontoiatrici, sarebbe stato possibile fare diagnosi elettrofisiologica di danno organico trigeminale? Certo che si perchè forse non avremmo assistito ad una assenza dei riflessi sia in latenza che in ampiezza ma sicuramente avremmo notato una notevole asimmetria ed un ritardo di latenza del periodo silente nonché una anomalia di ampiezza nei <sub>b</sub>Root-MEPs. In conclusione la correlazione tra sistema vestibolare e trigeminale benché sia presente da un punto di vista anatomico e neurofisiopatologico dovrebbe non essere considerata dalle procedure riabilitative masticatorie perchè troppo pericoloso un errore nella diagnosi differenziale.
+This detailed summary examines the complex interrelationships between dental malocclusion, postural disorders, and trigeminal neurophysiopathology through the clinical case of a patient known as 'Balancer.' The patient's decade-long suffering from a meningioma at the base of the skull illustrates the challenges and potential misdiagnoses that can occur when traditional dental perspectives are applied without considering deeper neurophysiological issues. The text integrates a broad range of medical insights to argue for a more nuanced approach to diagnosing and treating conditions that straddle neurology and dentistry.
-{{ArtBy|
+Introduction
+The chapter opens by highlighting the limitations of axiomatic assumptions in medical diagnoses, particularly in the complex interplay between dental health and neurological conditions. It introduces the case of 'Balancer,' whose symptoms were initially interpreted within a dental framework but later understood to be indicative of significant neurological pathology.
+Trigeminal Neurophysiopathology and Misdiagnosis
+The narrative delves into the specifics of trigeminal neurophysiopathology, explaining how the patient's meningioma exerted physical effects on both sensory and motor fibers of the trigeminal nerve system, leading to severe symptoms that were initially misinterpreted as dental issues. The discussion underscores the importance of considering neurophysiological data in dental diagnoses, particularly when patients present with atypical or severe symptoms that do not align with common dental disorders.
+Diagnostic Challenges and Electrophysiological Insights
+The summary critically evaluates the diagnostic process, emphasizing the role of electrophysiological tests such as the <sub>b</sub>Root-MEPs and assessments of the jaw jerk reflex. These tests revealed the extent of the damage more accurately than dental evaluations and highlighted the need for medical imaging to confirm the presence and impact of the meningioma.
+MRI Findings and Neurological Complications
+MRI results confirmed the severe implications of the meningioma, showing brainstem displacement and raising urgent questions about the initial stages of the tumor's development. This section reflects on whether earlier detection of the tumor through targeted electrophysiological testing could have altered the patient's treatment trajectory.
+Misleading Symptoms and the Importance of Accurate Diagnosis
+The patient's case is used to illustrate how symptoms like 'chewing difficulty' can be misleading. The narrative argues for a more integrated diagnostic approach that combines dental and neurological expertise to avoid oversimplified conclusions that may lead to inadequate treatments.
+Cognitive Neural Network (CNN) Diagnostic Model
+The use of a Cognitive Neural Network (CNN) in diagnosing 'Balancer's' condition is discussed, showcasing how advanced data analysis techniques can aid in distinguishing between symptoms related to dental malocclusions and those stemming from serious neurological conditions. This section details the sequential steps taken through the CNN to refine the diagnosis and better understand the underlying causes of the patient's symptoms.
+Clinical Implications and Future Directions
+The chapter concludes by discussing the broader clinical implications of the case for both dentistry and neurology. It calls for heightened awareness of the potential for neurological conditions to manifest through symptoms typically associated with dental issues and recommends more interdisciplinary approaches in medical training and practice to prevent similar diagnostic errors.
+Summary
+This summary not only provides a detailed recount of 'Balancer's' medical journey but also serves as a cautionary tale about the risks of compartmentalized medical thinking. It advocates for a holistic approach to patient care that respects the complex interconnections between different bodily systems and emphasizes the critical importance of accurate, comprehensive diagnostic practices in ensuring effective treatment outcomes.<blockquote>
+== Keywords ==
+'''Trigeminal Neurophysiopathology''' - Refers to the study of diseases that affect the trigeminal nerve, highlighting the nerve's role in conveying sensory information from the face to the brain. This term is crucial for medical content discussing neurological impacts on facial sensation and motor functions.
+'''Dental Malocclusion''' - Describes the misalignment of teeth and how they fit together when the jaws are closed. This keyword is key for dental health content, focusing on how teeth alignment affects overall oral health and potentially other bodily functions.
+'''Postural Disorders''' - Pertains to conditions that affect the posture or the way the body is positioned when standing or sitting. This term is particularly relevant in discussions about how spinal and muscular health can be influenced by neurological and dental health.
+'''Meningioma''' - A type of brain tumor that forms from the meninges, the layers of tissue covering the brain and spinal cord. This keyword is critical for content on brain tumors, discussing symptoms, diagnosis, and treatment options.
+'''Electrophysiological Tests''' - Refers to diagnostic tests that measure electrical activity in the body, such as nerve impulses. These tests are crucial in neurology content, especially in diagnosing and understanding the extent of nerve damage.
+'''Jaw Jerk Reflex''' - A reflex that helps diagnose disorders of the trigeminal nerve by tapping the jaw and observing the response. This keyword is relevant for neurological examination content, focusing on reflex testing.
+'''Cognitive Neural Network (CNN) in Diagnosis''' - Discusses the application of advanced data analysis techniques in medical diagnostics, especially for integrating and analyzing patient data for better diagnostic accuracy. This term is significant for content on medical technology and innovations in diagnostics.
+'''MRI Findings in Neurology''' - MRI (Magnetic Resonance Imaging) findings that provide insights into brain and nerve conditions, essential for content related to medical imaging techniques and their applications in diagnosing neurological disorders.
+'''Motor Evoked Potentials (MEPs)''' - A diagnostic measure of the electrical activity in response to stimulation of the motor cortex, used to assess the functionality of motor pathways, particularly relevant for neurophysiological testing content.
+'''Neurological and Dental Integration''' - Focuses on the interdisciplinary approach between neurology and dentistry to tackle complex cases that exhibit symptoms affecting both the neurological and dental systems, crucial for content on comprehensive patient care and diagnostic strategies.</blockquote>{{ArtBy|
 | autore = Gianni Frisardi
 | autore2 = Giorgio Cruccu
@@ Line 23: / Line 53: @@
 | autore5 =
 | autore6 =
-| }}{{Bookind2}}
+| }}
 ===Introduction===
-Nel capitolo introduttivo riguardante il 3° caso clinico  affetto da meningioma in cui il disturbo di difficoltà masticatoria riferito dal paziente 'Balancer' era stato correlato ad un problema riabilitativo protesico, si è già arrivati ad una primo filtro diagnostico considerando valida la asserzione neurologica a quella odontoiatrica. Di conseguenza ci si può concentrare sull'intercettazione dei test necessari per decriptare il codice del linguaggio macchina che il SNC invia all'esterno convertito in linguaggio verbale. Apparentemente questo linguaggio verbale indirizzerebbe il caso in  un disturbo Posturale correlato ad una malocclusione dentaria dovuta da incongrua riabilitazione protesica. Se da una lato ci può stare una asimmetria dello EMG interferenziale dei masseteri per uno sbilanciamento occlusale protesico dall'altra non è giustificabile una asimmetria così evidente del jaw jerk e del periodo silente. Per questo motivo è essenziale proseguire con il modello diagnostico Masticationpedia per giungere ad una diagnosi conclusiva esatta e rapida. Iniziamo perciò con lo 'Cognitive Neural Network' che risponde, come ormai sappiamo, con una sequenza di dati scientifico clinici, tenendo sempre in considerazione l'importanza dello step di 'iniziazione' che in questo caso è stato fissato in 'Gait'.<blockquote>
+In the introductory chapter concerning the 3rd clinical case affected by meningioma in which the masticatory difficulty reported by the patient 'Balancer' had been correlated to a prosthetic rehabilitation discrepancy, we have already arrived at a first diagnostic filter considering the neurological assertion to be valid than the dental one. Consequently, one can concentrate on intercepting the tests necessary to decrypt the machine language code that the CNS sends out converted into verbal language. Apparently this verbal language would address the case in a Postural disorder related to a dental malocclusion due to incongruous prosthetic rehabilitation. If, on the one hand, there may be an asymmetry of the interferential EMG of the masseters due to a prosthetic occlusal imbalance, on the other, such an evident asymmetry of the jaw jerk and the silent period cannot be justified. For this reason, it is essential to continue with the Masticationpedia diagnostic model in order to arrive at an exact and rapid conclusive diagnosis. We therefore begin with the 'Cognitive Neural Network' which responds, as we know by now, with a sequence of scientific-clinical data, always taking into consideration the importance of the 'initiation' step which in this case has been set in 'Gait'.
+<blockquote>
 <math>CNN=\sum ( </math> [https://pubmed.ncbi.nlm.nih.gov/?term=%27gait+%27&filter=datesearch.y_10&size=200 Gait] (45.300), [https://pubmed.ncbi.nlm.nih.gov/?term=%27gait+AND+motor+evoked+potentials+%27&filter=datesearch.y_10&size=200 motor evoked potentials]  (231),[https://pubmed.ncbi.nlm.nih.gov/?term=%27gait+AND+motor+evoked+potentials+AND+reflex%27&filter=datesearch.y_10&size=200 reflex] (36), [https://pubmed.ncbi.nlm.nih.gov/29696497/ jaw](1) <math>\longrightarrow</math> 'Cerebellar ataxia, neuropathy, vestibular areflexia syndrome (CANVAS) with chronic cough and preserved muscle stretch reflexes: evidence for selective sparing of afferent Ia fibres'</blockquote>
-===Sequenza diagnostica===
+===Diagnostic sequence ===
-====1st Step: CNN Sequence====
+====1st Step: CNN Sequence ====
-https://pubmed.ncbi.nlm.nih.gov/29696497/ (gait AND tendon reflex AND masseter)
-*'''''<math>\tau</math>''' Coherence Demarcator:'' Come abbiamo precedentemente descritto per gli altri casi clinici, il primo passo è un comando di inizializzazione della Cognitive Neural Network 'CNN' che deriva, appunto, da una precedente elaborazione cognitiva sulle asserzioni nel contesto odontoiatrico e neurologico in cui lo '<nowiki/>'''''<math>\tau</math>'''''  Demarcatore di Coerenza' ha dato un peso prevalente. Di fatto, il contesto odontoiatrico è stato già eliminato dal Demarcatore di Coerenza '''''<math>\tau</math>'''''. Da quanto emerge dalle asserzioni neurologiche lo 'Stato' del Sistema Nervoso Trigeminale appare fortemente danneggiato. Il comando di inizializzazione sarà, perciò, 'Gait'.
-*<nowiki/><nowiki/><u>1<sup>st</sup> loop open:</u> Il primo risultato del <nowiki>'CNN'' per la parola chiave '</nowiki>[https://pubmed.ncbi.nlm.nih.gov/?term=%27gait++%27&filter=datesearch.y_10&ac=yes&cauthor_id=None&user_filter=&schema=none&page=1&whatsnew=None&show_snippets=on&format=summary&sort=relevance&sort_order=desc&size=200 Gait]' restituisce 45,300 resultati, ovviamente, troppo vasto per essere esaustivo ma avendo constatato nella fase dell'analisi dei contesti una situazione elettrofisiologica trigeminale grave e con marcate anomalie strutturali e funzionali, possiamo tranquillamente inserire una chiave correlata come ' Motor Evoked Potentials' senza specificare il distretto trigeminale che potrebbe sconfinare dall'insieme individuato.
-*
-*
-*
-*<u>2<sup>st</sup></u><nowiki/><nowiki/> <u>loop o</u><nowiki/><nowiki/><u>pen:</u> A questa seconda interrogazione '[https://pubmed.ncbi.nlm.nih.gov/?term=%27gait+AND+motor+evoked+potentials+%27&filter=datesearch.y_10&size=200 Motor Evoked Potentials]' il database risponde con 231 resultati ancora troppo vasta come risposta e dunque si cerca una chiave più affine al caso clinico presentato. Visto che i risultati più anomali nel contesto neurologico sono emersi dalle alterazioni di latenza ed ampiezza dei riflessi trigeminali, una appropriata chiave di accesso potrebbe essere, appunto, 'Reflex' anch'essa senza specificare 'trigeminal' per gli stessi motivi anticipati.
+*'''''<math>\tau</math>''' Coherence Demarcator:'' As we have previously described for the other clinical cases, the first step is an initialization command of the Cognitive Neural Network 'CNN' which derives, in fact, from a previous cognitive elaboration on the assertions in the dental and neurological context in which the ' Demarcator of Consistency' gave a prevailing weight. The dental context has already been eliminated from the Consistency Demarcator. From what emerges from the neurological statements, the 'State' of the Trigeminal Nervous System' appears to be strongly damaged. The initialization command will therefore be 'Gait'.
-*<u>3<sup>st</sup> loop open:</u> Alla richiesta '[https://pubmed.ncbi.nlm.nih.gov/?term=%27gait+AND+motor+evoked+potentials+AND+reflex%27&filter=datesearch.y_10&size=200 Reflex]' la risposta fu di 36 risultati che hanno ristretto il campo di analisi per la diagnosi del nostro paziente 'Balancer'. Soltanto a questo livello del CNN si può tentare di chiudere il loop con una richiesta più specifica del tipo 'Jaw'. In questo modo non abbiamo perso il contatto con l'insieme considerato e siamo rimasti nel campo dell'elettrofisiologia.
-*<u>4<sup>st</sup> loop open:</u> La richiesta '[https://pubmed.ncbi.nlm.nih.gov/29696497/ jaw]' infatti nei 36 risultati si può intercettare un articolo in cui vengono riportati alcuni parametri elettrofisiologici che corrispondono ad una situazione clinica di atassia cerebellare, una patologia in cui l'instabilità Posturale e di deambulazione è un segno clinico imponente ed importante.
-=====2st Step: Analisi CNN=====
+* 1st loop open: The first result of the 'CNN' for the keyword '[https://pubmed.ncbi.nlm.nih.gov/?term=%27gait++%27&filter=datesearch.y_10&ac=yes&cauthor_id=None&user_filter=&schema=none&page=1&whatsnew=None&show_snippets=on&format=summary&sort=relevance&sort_order=desc&size=200 Gait]' returns 45,300 results, obviously, too vast to be exhaustive but having ascertained in the context analysis phase a serious trigeminal electrophysiological situation with marked structural anomalies and functional, we can safely enter a correlated key such as ' Motor Evoked Potentials' without specifying the trigeminal district which could encroach on the identified set.
-L'anali di chiusura del loop dello 'CNN' ovviamente si basa sull'articolo terminale  '[https://pubmed.ncbi.nlm.nih.gov/29696497/ Jaw]' che sostanzialmente descrivere cinque pazienti con atassia cerebellare, neuropatia e sindrome da areflessia vestibolare (CANVAS) con tosse cronica e riflessi di stiramento muscolare degli arti inferiori preservati. In particolare i potenziali evocati somatosensoriali erano assenti o gravemente attenuati. Le registrazioni del riflesso T bicipite e femorale erano normali, mentre il riflesso masseterino era assente o attenuato.<blockquote>[[File:Meningioma 2 by Gianni Frisardi.jpeg|link=link=Special:FilePath/Meningioma_2_by_Gianni_Frisardi.jpg|alt=|thumb|'''Figura 1:''' Asserzione neurologica <math>\gamma_1</math> che evidenzia una grave anomalia di latenza ed ampiezzza del jaw jerk destro]]La prima osservazione da fare è che i pazienti erano affetti da tosse cronica spasmodica e la seconda osservazione era la preservazione dei riflessi tendine degli arti inferiori. Nel nostro paziente 'Balancer' invece sussisteva l'assenza totale del riflesso tendine mandibolare<ref>The history of examination of reflexes. Boes CJ.J Neurol. 2014 Dec;261(12):2264-74. doi: 10.1007/s00415-014-7326-7. Epub 2014 Apr 3.PMID: 24695995 </ref> (<math>\gamma_1</math>) per cui il danno neurologico era molto evidente a livello mesencefalico trigeminale. (Figura 1) L'apporto multifunzionale della circuiteria sinaptica mesencefalica da parte delle terminazioni nervose propriocettive ( <math>1a</math> e <math>\gamma</math>) sono di primaria importanza sia per la postura che per i riflessi cervico-oculomotori. Un  articolo molto interessante di Yongmei Chen et al.<ref>Chen Y, Gong X, Ibrahim SIA, Liang H, Zhang J.. Convergent innervations of mesencephalic trigeminal and vestibular nuclei neurons onto oculomotor and pre-oculomotor neurons-Tract tracing and triple labeling in rats. PLoS One. 2022 Nov 28;17(11):e0278205. doi: 10.1371/journal.pone.0278205. eCollection 2022.PMID: 36441755 </ref> ha  mostrato, attraverso marcatori, come i neuroni afferente al nucleo  mesencefalico trigeminale  (Vme) dai muscoli mascellari proiettino ai nuclei oculomotori (III/IV) e ai loro neuroni premotori nel nucleo interstiziale di Cajal (INC), un noto centro pre-oculomotore che manipola verticalmente movimenti oculari torsionali.
+*2st loop open: To this second query '[https://pubmed.ncbi.nlm.nih.gov/?term=%27gait+AND+motor+evoked+potentials+%27&filter=datesearch.y_10&size=200 Motor Evoked Potentials]'  the database replies with 231 results that are still too vast as an answer and therefore we are looking for a key more similar to the clinical case presented. Since the most anomalous results in the neurological context have emerged from the latency and amplitude alterations of the trigeminal reflexes, an appropriate access key could be, in fact, 'Reflex' also without specifying 'trigeminal' for the same anticipated reasons.
+*3st loop open: To the '[https://pubmed.ncbi.nlm.nih.gov/?term=%27gait+AND+motor+evoked+potentials+AND+reflex%27&filter=datesearch.y_10&size=200 Reflex]'request, the response was 36 results which narrowed the field of analysis for the diagnosis of our patient 'Balancer'. Only at this level of the CNN can one attempt to close the loop with a more specific request such as 'Jaw'. In this way we have not lost contact with the whole considered and we have remained in the field of electrophysiology.
+*4st loop open: The request '[https://pubmed.ncbi.nlm.nih.gov/29696497/ jaw]' in fact in the 36 results it is possible to intercept an article in which some electrophysiological parameters are reported which correspond to a clinical situation of cerebellar ataxia, a pathology in which postural and gait instability is a clinical sign impressive and important.
+<nowiki/><nowiki/>
+=====2st Step: CNN analysis =====
+The 'CNN' loop closure analy of course is based on the terminal article which basically describe five patients with cerebellar ataxia, neuropathy and vestibular areflexia syndrome (CANVAS) with chronic cough and lower limb muscle stretch reflexes preserve yourself.<ref name=":0">Jon Infante, Antonio García, Karla M Serrano-Cárdenas, Rocío González-Aguado, José Gazulla, Enrique M de Lucas, José Berciano. Cerebellar ataxia, neuropathy, vestibular areflexia syndrome (CANVAS) with chronic cough and preserved muscle stretch reflexes: evidence for selective sparing of afferent Ia fibres.J Neurol . 2018 Jun;265(6):1454-1462. doi: 10.1007/s00415-018-8872-1.Epub 2018 Apr 25.
+</ref> In particular, somatosensory evoked potentials were absent or severely attenuated. Biceps and hamstring T-reflex recordings were normal, while the masseter reflex was absent or attenuated.<blockquote>[[File:Meningioma 2 by Gianni Frisardi.jpeg|link=link=Special:FilePath/Meningioma_2_by_Gianni_Frisardi.jpg|alt=|thumb|'''Figure 1:''' Neurological statement highlighting a severe right jaw jerk latency and amplitude abnormality]]The first observation to be made is that the patients were suffering from chronic spasmodic cough and the second observation was the preservation of the tendon reflexes of the lower limbs. In our patient 'Balancer', on the other hand, there was a total absence of the mandibular tendon reflex<ref>The history of examination of reflexes. Boes CJ.J Neurol. 2014 Dec;261(12):2264-74. doi: 10.1007/s00415-014-7326-7. Epub 2014 Apr 3.PMID: 24695995 </ref> (<math>\gamma_1</math>) so that the neurological damage was very evident at the trigeminal midbrain level. (Figure 1) The multifunctional contribution of the midbrain synaptic circuitry by the proprioceptive nerve endings ( <math>1a</math> e <math>\gamma</math>) are of primary importance both for posture and for cervico-oculomotor reflexes. A very interesting article by Yongmei Chen et al.<ref>Chen Y, Gong X, Ibrahim SIA, Liang H, Zhang J.. Convergent innervations of mesencephalic trigeminal and vestibular nuclei neurons onto oculomotor and pre-oculomotor neurons-Tract tracing and triple labeling in rats. PLoS One. 2022 Nov 28;17(11):e0278205. doi: 10.1371/journal.pone.0278205. eCollection 2022.PMID: 36441755 </ref> showed, through markers, how neurons afferent to the trigeminal mesencephalic nucleus (Vme) from the jaw muscles project to the oculomotor nuclei (III/IV) and their premotor neurons in the interstitial nucleus of Cajal (INC), a well-known pre-oculomotor center that vertically manipulates torsional eye movements.
-La conclusione concettuale degli autori è stata che i neuroni Vme propriocettivi dei muscoli masticatori proiettanti al III/IV e INC rileverebbero l'attività del fuso ai cambiamenti spaziali della mascella condizionata dalla forza di gravità e/o dalla connessione tra la mandibola durante la rotazione della testa. Pertanto, l'innervazione convergente dei neuroni Vme e MVN sui nuclei oculomotore e pre-oculomotore sarebbe un substrato neuroanatomico per l'interazione della propriocezione masticatoria con i segnali vestibolo-oculari sul sistema oculomotore durante il VOR verticale-torsionale. Il contributo di questo articolo ci consente di considerare, ovviamente, una correlazione tra il sistema trigeminale, la postura e la deambulazione, pertanto, l'abnorme asimmetria del jaw jerk potrebbe essere correlato ad un disturbo posturale del nostro paziente 'Balancer'
+The conceptual conclusion of the authors was that the Vme proprioceptive neurons of the masticatory projecting muscles at III/IV and INC would detect spindle activity to spatial changes of the jaw conditioned by the force of gravity and/or by the connection between the mandible during rotation of the head. Thus, the convergent innervation of Vme and MVN neurons on the oculomotor and pre-oculomotor nuclei would be a neuroanatomical substrate for the interaction of masticatory proprioception with vestibulo-ocular signals on the oculomotor system during vertical-torsional VOR. The contribution of this article obviously allows us to consider a correlation between the trigeminal system, posture and gait, therefore, the abnormal asymmetry of the jaw jerk could be related to a postural disorder of our patient 'Balancer'
+ </blockquote>
+But there is also to consider the article of Jon Infante <ref name=":0" /> highlighted that all five patients were in the seventh decade of age, their gait imbalance having started in the fifth decade. In four patients, cough preceded gait imbalance between 15 and 29 years of age; the cough was spasmodic and triggered by variable factors. In addition, vestibular function tests showed bilateral impairment of the vestibulo-ocular reflex.  <blockquote>[[File:Meningioma 6 by Gianni Frisardi.jpeg|link=link=Special:FilePath/Meningioma_6_by_Gianni_Frisardi.jpg|alt=|thumb|'''Figure 2:''' Occlusal aspect of the 'Balancer' patient who had the occlusal incongruity on the right side restored several times.]]
+The presence of chronic spasmodic cough, in this study, for over 10 years even before balance and postural disturbances showed up, suggest that machine language, as repeatedly exposed in the specific chapters of Masticationpedia, is a reality not to be overlooked because the ambiguous and vague verbal language covers the information of the encrypted code. As we will demonstrate in the course of the discussion, the analog of the spasmodic cough symptom of the patients reported by Jon Infante's article could be the repeated reporting to the dental colleagues of the chewing difficulty by our patient 'Balancer'. (Figure 2) This parameter has not been considered as an 'encrypted code' but only an element of verbal language logic and therefore vague and ambiguous. The continuous remaking of the prosthetic rehabilitation dampened even more the information of the machine language until the temporal and spatial addition of the organic damage was transformed<ref name=":0" /> into a macroscopic symptom of vertigo and loss of balance in walking  </blockquote>
-</blockquote>
+Jon Infante's article<ref name=":0" /> concludes with a striking statement, i.e. that '''spasmodic cough''' can be an integral part of the clinical picture in CANVAS, anticipating the appearance of postural imbalance by several decades and ''that sparing of muscle spindle afferents (Ia fibers) is probably the pathophysiological basis of normoreflexia.''
-Tutti e cinque i pazienti erano nella settima decade di età, il loro squilibrio dell'andatura era iniziato nella quinta decade. In quattro pazienti la tosse ha preceduto lo squilibrio dell'andatura tra i 15 ai 29 anni; la tosse era spasmodica e scatenata da fattori variabili. Inoltre i test di funzionalità vestibolare hanno mostrato una compromissione bilaterale del riflesso vestibolo-oculare.  <blockquote>[[File:Meningioma 6 by Gianni Frisardi.jpeg|link=link=Special:FilePath/Meningioma_6_by_Gianni_Frisardi.jpg|alt=|thumb|'''Figura 2:''' Aspetto occlusale del paziente 'Balancer' a cui era stato più volte ripristinata l'incongrua occlusale sul lato destro.]]
-La presenza della tosse cronica spasmodica, in questo studio,  da oltre 10 anni ancor prima che si presentassero disturbi dell'equilibrio e posturali lasciano intendere che il linguaggio macchina, come più volte esposto nei capitoli specifici di Masticationpedia, è una realtà da non trascurare perchè il linguaggio verbale ambiguo e vago copre l'informazione del codice criptato. Come avremo modo di dimostrare nel corso della discussione l'analogo del sintomo tosse spasmodica dei pazienti riportati dall'articolo di Jon Infante<ref name=":0">Jon Infante, Antonio García, Karla M Serrano-Cárdenas, Rocío González-Aguado, José Gazulla, Enrique M de Lucas, José Berciano. Cerebellar ataxia, neuropathy, vestibular areflexia syndrome (CANVAS) with chronic cough and preserved muscle stretch reflexes: evidence for selective sparing of afferent Ia fibres.J Neurol . 2018 Jun;265(6):1454-1462. doi: 10.1007/s00415-018-8872-1.Epub 2018 Apr 25.
-</ref>potrebbe essere il ripetuto riferire ai colleghi odontoiatrici della difficoltà masticatoria da parte del nostro paziente 'Balancer'. (Figura 2) Questo parametro non è stato considerato come 'codice criptato' ma solo elemento di logica di linguaggio verbale e dunque vago ed ambiguo. Il rifacimento continuo della riabilitazione protesica smorzava ancor di più l'informazione del linguaggio macchina fino a che la sommazione temporale e spaziale del danno organico si trasformasse in sintomo macroscopico di vertigini e di perdita di equilibrio nella deambulazione.  </blockquote>
-L'articolo di Jon Infante<ref name=":0" /> conclude con una affermazione eclatante e cioè che la '''tosse spasmodica''' può essere parte integrante del quadro clinico nei CANVAS, anticipando la comparsa dello squilibrio posturale di diversi decenni e che ''<u>il risparmio delle afferenze del fuso muscolare (fibre Ia) è probabilmente la base fisiopatologica della normoreflessia.</u>'' {{Q2|Siamo giunti alla conclusione che il disturbo posturale del paziente non poteva essere correlato con l'incongruenza occlusale riabilitativa bensì ad un danno neurologico ma la domanda ora è la seguente:|.il danno neurologico è di tipo funzionale oppure organico?}}
+{{Q2|We came to the conclusion that the patient's postural disorder could not be related to the rehabilitative occlusal incongruity but to a neurological damage but the question now is the following:|........is the neurological damage functional or organic?}}
-===Processo di decriptazione===
+=== Decryption process ===
-L'iter diagnostico seguito ormai di routine secondo il modello Masticationpedia ci ha consentito di eliminare, attraverso il demarcatore di coerenza <math>\tau</math>, il contesto odontoiatrico per seguire quello neurologico e di approfondire attraverso lo 'Cognitive Neural Network' (CNN) le possibili correlazioni tra sintomi e anomalie neurofisiologiche nei pazienti con disturbi posturali, di deambulazione dovute a patologie funzionali ( labirintiti, neuropatie ecc.) da quelle organiche ( tumori, demielinizzazioni ecc.). Ora bisogna cercare di decriptare il messaggio criptato del linguaggio macchina del Sistema Nervoso Trigeminale.
+The diagnostic procedure followed routinely according to the Masticationpedia model has allowed us to eliminate, through the coherence demarcator, the dental context to follow the neurological one and to deepen through the 'Cognitive Neural Network' (CNN) the possible correlations between symptoms and neurophysiological abnormalities in patients with postural and walking disorders due to functional pathologies (labyrinthitis, neuropathies, etc.) from organic ones (tumors, demyelinations, etc.). Now we must try to decrypt the encrypted message of the machine language of the Trigeminal Nervous System.
-====Codice criptato====
+====Encrypted code====
-[[File:Ortognatica Jaw jerk.jpg|link=link=Special:FilePath/Ortognatica_Jaw_jerk.jpeg|alt=|thumb|'''Figura 2:''' Determinazione della componente funzionale del Sistema Nervoso Centrale. I risultati per il paziente 2 (normocclusione) mostrano un'area di 1,37 mV/ms e 0,13 mV/ms rispettivamente sul massetere destro e sinistro. Questo mostra una asimmetria tra lati di circa il 100%.]][[File:Meningioma 2 by Gianni Frisardi.jpeg|link=link=Special:FilePath/Meningioma_2_by_Gianni_Frisardi.jpg|alt=|thumb|'''Figura 1:''' Asserzione neurologica <math>\gamma_1</math> che evidenzia una grave anomalia di latenza del jaw jerk|left]]Come anticipato, in primis abbiamo potuto evidenziare una grave assenza del jaw jerk riportata come  <math>\gamma_1=1\longrightarrow</math> Anormalità, positività del referto ( Figura 1) ma come è stato già menzionato nel capitolo ' [[Conclusioni sullo status quo nella logica del linguaggio medico riguardo al sistema masticatorio]]' anche nel paziente trattato con chirurgia ortognatica abbiamo potuto rilevare una assenza del jaw jerk (figura 2) ripristinato subito dopo riabilitazione neurognatologica evocata. Nel nostro caso 'Balancer' abbiamo un disturbo oggettivo in più quello della difficoltà masticatoria ed insieme al disturbo posturale erano presenti nistagno e vertigini.
+[[File:Ortognatica Jaw jerk.jpg|link=link=Special:FilePath/Ortognatica_Jaw_jerk.jpeg|alt=|thumb|'''Figure 2:''' Determination of the functional component of the Central Nervous System. The results for patient 2 (normocclusion) show an area of 1.37 mV/ms and 0.13 mV/ms on the right and left masseter, respectively. This shows an asymmetry between sides of about 100%.]][[File:Meningioma 2 by Gianni Frisardi.jpeg|link=link=Special:FilePath/Meningioma_2_by_Gianni_Frisardi.jpg|alt=|thumb|'''Figure 1:''' Neurological statments <math>\gamma_1</math> highlighting severe jaw jerk latency abnormality |left]]
-Un ulteriore asserzione a favore del danno organico è stato anche la presenza di un ritardo di latenza sul lato destro del periodo silente elettrico,  <math>\gamma_3=1\longrightarrow</math> Anormalità, positività del referto, che depone per un rallentamento della velocità di conduzione nervosa. In questo istanza non possiamo dire se il ritardo sia riferito ad un danno delle fibre sensitive o di quelle motorie fintanto che non si approccia allo studio della conduzione nervosa delle radici trigeminali motorie.
+As anticipated, first of all we were able to highlight a serious absence of the jaw jerk reported as  <math>\gamma_1=1\longrightarrow</math> Abnormality, positive report (Figure 1) but as already mentioned in the chapter
+' [[Conclusions on the status quo in the logic of medical language regarding the masticatory system]]'  also in the patient treated with orthognathic surgery we were able to detect an absence of the jaw jerk (figure 2) restored immediately after evoked neurognathological rehabilitation. In our case 'Balancer' we have an additional objective disorder that of masticatory difficulty and together with the postural disorder there were nystagmus and vertigo.
-=====Potenziali Evocati Motori della radice trigeminale=====
+A further assertion in favor of organic damage was also the presence of a latency delay on the right side of the electrical silent period, <math>\gamma_3=1\longrightarrow</math> Abnormality, positivity of the report, which suggests a slowing of the nerve conduction speed. In this instance we cannot say whether the delay refers to damage to the sensory or motor fibers until we approach the study of the nerve conduction of the motor trigeminal roots.
-[[File:Meningioma 5 by Gianni Frisardi.jpeg|link=link=Special:FilePath/Meningioma_5_by_Gianni_Frisardi.jpg|alt=|300x300px|thumb|'''Figura 4:''' Referto RMN di meningioma in base cranica destra]][[File:Meningioma 3 by Gianni Frisardi.jpeg|thumb|'''Figura 3:''' Risposte evocate da stimolazione elettrica transcraniale bilaterale. E' evidente una marcata asimmetria di ampiezza a carico del Massetere destro.|alt=|left]]
+=====Motor evoked potentials of the trigeminal root=====
-Nel nostro laboratorio di neurofisiologia masticatoria abbiamo messo a punto una tecnica di elettrostimolazione trasncraniale elettrica delle due radici trigeminali in simultanea e sincronizzate con lo stimolo elettrico. Nei vari capitoli già pubblicati sono riportati alcune informazioni tecniche sul metodo ma ci ripromettiamo di esporli in modo esaustivo nella sezione 'Scienza straordinaria'. In questo contesto possiamo solo considerare e confermare una asimmetria notevole di ampiezza delle risposte evocate motorie come mostrato in figura 3. I markers 1A e 2A indicano la latenza chea differenza del periodo silente è simmetrica e questo dato conferma il danno strutturale delle fibre sensitive comprese quelle propriocettive dai muscoli masticatori. Possiamo a questo punto non solo confermare e giustificare la scelta neurologica del contesto diagnostico ma anche concludere con una pre diagnosi di danno neurologico cerebellare con coinvolgimento dell'asse mesencefalico trigeminale.
+[[File:Meningioma 5 by Gianni Frisardi.jpeg|link=link=Special:FilePath/Meningioma_5_by_Gianni_Frisardi.jpg|alt=|300x300px|thumb|'''Figure 4:''' MRI report of meningioma in right skull base]][[File:Meningioma 3 by Gianni Frisardi.jpeg|thumb|'''Figure 3:''' Bilateral transcranial electrical stimulation evoked responses. A marked asymmetry of amplitude in the right Masseter is evident.|alt=|left]]
+In our masticatory neurophysiology laboratory we have developed a technique of electrical transcranial electrostimulation of the two trigeminal roots simultaneously and synchronized with the electrical stimulus. In the various chapters already published some technical information on the method is reported but we intend to expose them exhaustively in the section 'Extraordinary science'. In this context we can only consider and confirm a significant amplitude asymmetry of the motor evoked responses as shown in figure 3. The markers 1A and 2A indicate the latency which, unlike the silent period, is symmetrical and this data confirms the structural damage of the sensory fibers including those proprioceptive from masticatory muscles. At this point we can not only confirm and justify the neurological choice of the diagnostic context but also conclude with a pre-diagnosis of cerebellar neurological damage with involvement of the trigeminal mesencephalic axis.
-La  Risonanza Magnetica dell'encefalo, purtroppo, risolve i nostri dubbi con una refertazione di lesione espansiva solida con effetto massa nell'emisfero destro, non è chiaro se abbia un’origine sopra o sotto tentoriale, sicuramente determina fenomeni compressivi sul mesencefalo - tronco e sul quarto ventricolo con dilatazione delle cisterne e dei ventricoli a monte. Che si tratti di un meningioma è molto probabile perché non ha edema perilesionale.<center></center>
+The Magnetic Resonance of the brain, unfortunately, solves our doubts with a report of solid expansive lesion with mass effect in the right hemisphere, it is not clear whether it has a supra or sub tentorial origin, it certainly determines compressive phenomena on the midbrain - trunk and on the fourth ventricle with dilatation of the cisternae and ventricles upstream. That it is a meningioma is very likely because he has no perilesional edema.<center></center>
 ==='''Final considerations'''===
-Riassumiamo il percorso clinico diagnostico seguendo il modello Masticationpedia perched si possa considerare quest'ultimo un fluido e dinamico iter per giungere a target diagnostico nel modo più rapido e dettagliato.
+We summarize the clinical diagnostic path following the Masticationpedia model so that the latter can be considered a fluid and dynamic process to reach a diagnostic target in the fastest and most detailed way.
-# Analisi dei contesti attraverso test di laboratorio odontoiatrici e neurologici
+# Context analysis through dental and neurological laboratory tests
-# Scelta dell'asserzione neurologica attraverso filtro da parte del Demarcatore di Coerenza '''''<math>\tau</math>'''''
+#Choice of neurological statement filtered by the '''''<math>\tau</math>''''' ''Coherence Demarcator''
-# Valutazione del caso clinico nel Cognitive Neural Network (CNN)
+# Evaluation of the clinical case in the Cognitive Neural Network (CNN)
-# Chiusura del loop del CNN con l'articolo di Jon Infante <ref name=":0" /> e la considerazione del danno organico/funzionale delle strutture sensitivo motorie trigeminali del nostro paziente attraverso constatazione della asimmetria di ampiezza della '<sub>b</sub>Root-MEPs'. Nella galleria di immagini è stata ordinata la sequenza logica dei test eseguiti con ripristino della numerazione.
+#Closing the CNN loop with Jon Infante's article<ref name=":0" /> and the consideration of the organic/functional damage of our patient's trigeminal sensory-motor structures through the observation of the amplitude asymmetry of the 'bRoot-MEPs'. The logical sequence of the tests carried out with the numbering restored has been ordered in the image gallery.
 <Center>
 <gallery widths="340" heights="300" perrow="2" slideshow""="">
-File:Meningioma 3 by Gianni Frisardi.jpeg|'''Figura 1a:''' Il primo test che va sempre eseguito in casi clinici complessi è, appunto, la <sub>b</sub>Root-MEPs
+File:Meningioma 3 by Gianni Frisardi.jpeg|'''Figure 1a:''' The first test that must always be performed in complex clinical cases is, in fact, the <sub>b</sub>Root-MEPs
-File:Meningioma 2 by Gianni Frisardi.jpeg|'''Figura 1b:''' Il secondo test è il jaw jerk che restituisce una sorta di analisi dell'integrità del sistema mesencefalico. Nel nostro caso 'Balancer' è evidente una abnorme asimmetria a discapito del massetere destro
+File:Meningioma 2 by Gianni Frisardi.jpeg|'''Figure 1b:''' The second test is the jaw jerk which returns a sort of analysis of the integrity of the midbrain system. In our case 'Balancer' an abnormal asymmetry is evident to the detriment of the right masseter
-File:Meningioma 4 by Gianni Frisardi.jpeg|'''Figura 1c:''' Dopo aver verificato il livello di integrità dell'area mesencefali attraverso test che coinvolgono riflessi monosinaptici come il jaw jerk si alza il livello di complessità evocando il periodo silente elettrico che è un riflesso polisinaptico. Appare evidente il ritardo di latenza sul massetere destro
+File:Meningioma 4 by Gianni Frisardi.jpeg|'''Figure 1c:''' After verifying the level of integrity of the midbrain area through tests involving monosynaptic reflexes such as jaw jerk, the level of complexity is raised by evoking the electrical silent period which is a polysynaptic reflex. The latency delay on the right masseter is evident
-File:Meningioma 5 by Gianni Frisardi.jpeg|'''Figura 1d:''' Ovviamente dopo questi risultati, il paziente non può essere considerato affetto da disturbo posturale bensì da patologia neurologica organica e la Risonanza Magnetica Nucleare dell'encefalo lo evidenzia in tutto la sua potenzialità diagnostica.
+File:Meningioma 5 by Gianni Frisardi.jpeg|'''Figure 1d:''' Obviously after these results, the patient cannot be considered affected by postural disorder but by organic neurological pathology and the Nuclear Magnetic Resonance of the brain shows it in all its diagnostic potential.
 </gallery>
-----
 </Center>
-=== Conclusioni ===
+===Conclusion===
-Abbiamo ormai evidenze di correlazione organico funzionali sia dirette che indirette tra il sistema trigeminale ed il sistema vestibolare, basti pensare allo studio dei mVEMP (Vestibular Evoked Myogenic Potentials) ormai riconosciuto come un test solido e affidabile per valutare l'integrità funzionale della via del riflesso vestibolo-masseterico,<ref>Sangu Srinivasan Vignesh, Niraj Kumar Singh, Krishna Rajalakshmi. Tone Burst Masseter Vestibular Evoked Myogenic Potentials: Normative Values and Test-Retest Reliability. J Am Acad Audiol. 2021 May;32(5):308-314. doi: 10.1055/s-0041-1728718.Epub 2021 Jun 1.
+We now have evidence of both direct and indirect functional organic correlation between the trigeminal system and the vestibular system, just think of the study of mVEMP (Vestibular Evoked Myogenic Potentials) now recognized as a solid and reliable test for assessing the functional integrity of the reflex pathway vestibulo-masseteric<ref>Sangu Srinivasan Vignesh, Niraj Kumar Singh, Krishna Rajalakshmi. Tone Burst Masseter Vestibular Evoked Myogenic Potentials: Normative Values and Test-Retest Reliability. J Am Acad Audiol. 2021 May;32(5):308-314. doi: 10.1055/s-0041-1728718.Epub 2021 Jun 1.
+</ref> in clinical manifestations with involvement of the trigeminal and vestibular system as in schwannomas<ref>Ashutosh Kumar, Sanjay Behari, Jayesh Sardhara, Prabhaker Mishra, Vivek Singh, Vandan Raiyani, Kamlesh Singh Bhaisora, Arun Kumar Srivastava . Quantitative assessment of brainstem distortion in vestibular schwannoma and its implication in occurrence of hydrocephalus.Br J Neurosurg . 2022 Dec;36(6):686-692. doi: 10.1080/02688697.2022.2047155.Epub 2022 Mar 7.
+</ref><ref>Daniel Moualed, Jonathan Wong, Owen Thomas, Calvin Heal, Rukhtam Saqib, Cameron Choi, Simon Lloyd, Scott Rutherford, Emma Stapleton, Charlotte Hammerbeck-Ward, Omar Pathmanaban, Roger Laitt, Miriam Smith, Andrew Wallace, Mark Kellett, Gareth Evans, Andrew King, Simon Freeman. Prevalence and natural history of schwannomas in neurofibromatosis type 2 (NF2): the influence of pathogenic variants. Eur J Hum Genet. 2022 Apr;30(4):458-464. doi: 10.1038/s41431-021-01029-y.Epub 2022 Jan 24.
+</ref> or in the presence of acoustic neuromas<ref>Claudia Cassandro, Roberto Albera, Luca Debiasi, Andrea Albera, Ettore Cassandro, Alfonso Scarpa, Massimo Ralli. What factors influence treatment decision making in acoustic neuroma? Our experience on 103 cases. Int Tinnitus J. 2020 Nov 18;24(1):21-25.doi: 10.5935/0946-5448.20200004.
+</ref> as much as the relative correlation between dental occlusion and the vestibular system but this does not allow, given the seriousness of the diagnostic error that it would result, to consider this last clinical condition a clinically validated scientific datum. In the Appendix an example of what might happen.
+This last assertion, perhaps risky because it is controversial, collides with the evidence of a striking fact highlighted several times during the drafting of the chapters of Masticationpedia, that of machine language and verbal language. A vague and ambiguous verbal language can generate scientific convictions depending on how it is proposed but in substance it covers and hides a much more decisive and formal machine language. For example, the verbal language deduced that the postural disturbances of the 'Balancer' patient were caused by an incongruous prosthetic rehabilitation while the machine language signaled an organic sensorineural deficit (absence of the jaw jerk, latency delays of the silent period, large reduction in the amplitude of the <sub>b</sub>Root-MEPs.
-</ref> nelle manifestazioni cliniche con  coinvolgimenti del sistema trigeminale e vestibolare come nei schwannomi<ref>Ashutosh Kumar, Sanjay Behari, Jayesh Sardhara, Prabhaker Mishra, Vivek Singh, Vandan Raiyani, Kamlesh Singh Bhaisora, Arun Kumar Srivastava . Quantitative assessment of brainstem distortion in vestibular schwannoma and its implication in occurrence of hydrocephalus.Br J Neurosurg . 2022 Dec;36(6):686-692. doi: 10.1080/02688697.2022.2047155.Epub 2022 Mar 7.
-</ref><ref>Daniel Moualed, Jonathan Wong, Owen Thomas, Calvin Heal, Rukhtam Saqib, Cameron Choi, Simon Lloyd, Scott Rutherford, Emma Stapleton, Charlotte Hammerbeck-Ward, Omar Pathmanaban, Roger Laitt, Miriam Smith, Andrew Wallace, Mark Kellett, Gareth Evans, Andrew King, Simon Freeman. Prevalence and natural history of schwannomas in neurofibromatosis type 2 (NF2): the influence of pathogenic variants. Eur J Hum Genet. 2022 Apr;30(4):458-464. doi: 10.1038/s41431-021-01029-y.Epub 2022 Jan 24.
+The lack of information on the velocity and the mandibular position at the midbrain level, in fact, determines an incapacity of stereognostic awareness in which the patient does not recognize the spatial and temporal position of the mandible. The decrease in the recruitment of the motor units of the masticatory muscles and not only of the tested masseter with an obvious decrease in the masticatory force is the result of this organic and functional damage. All this indicates an impairment of the proprioceptive territory but we do not know if the sensory structures have also been involved. The electrical silent period, on the other hand, shows a severe delay in latency with a slowing of nerve conduction velocity. To conclude the neurophysiopathological diagnostic picture is the observation that the right trigeminal motor root has lost most of its motor fibers.
-</ref> od in presenza di neurinomi dell'acustico<ref>Claudia Cassandro, Roberto Albera, Luca Debiasi, Andrea Albera, Ettore Cassandro, Alfonso Scarpa, Massimo Ralli. What factors influence treatment decision making in acoustic neuroma? Our experience on 103 cases. Int Tinnitus J. 2020 Nov 18;24(1):21-25.doi: 10.5935/0946-5448.20200004.
+However, it should be noted that in such a serious clinical condition we see a decrease in the amplitude of the <sub>b</sub>Root-MEPs but not a latency asymmetry. This finding indicates that there was direct damage to the trigeminal motor fibers from tumor compression (axonotmesis) but not demyelination (neuropraxia) which would have shown latency delay on the right masseter. It is advisable to briefly describe the definition of neurological damage bearing in mind that the equivalent of the spinal peripheral nerve for the trigeminal nervous system corresponds to the motor trigeminal root.
-</ref> tanto quanto la relativa correlazione tra occlusione dentale e sistema vestibolare ma ciò non consente, visto la gravità dell'errore diagnostico che ne deriverebbe, di considerare quest'ultima condizione clinica un dato scientifico validato clinicamente. InAppendice un esempio di ciò che potrebbe accadere.
-Quest'ultima asserzione, forse rischiosa perchè di controversione, si scontra sull'evidenza di un fatto eclatante più volte evidenziato nel corso della stesura dei capitoli di Masticationpedia quello del linguaggio macchina e del linguaggio verbale. Un linguaggio verbale vago ed ambiguo può generare convinzioni scientifiche a seconda di come viene proposto ma in sostanza copre ed occulta un linguaggio macchina molto più determinante e formale. Per esempio il linguaggio verbale ha dedotto che i disturbi posturali del paziente 'Balancer' fossero causati da una incongrua riabilitazione protesica mentre il linguaggio macchina segnalava un deficit neurosensoriale organico ( assenza del jaw jerk, ritardi in latenza del periodo silente, ampia riduzione di ampiezza della <sub>b</sub>Root-MEPs.
+'''Neurotmesis''' is caused by a transection of a nerve and is the worst degree of peripheral nerve injury. In neurotmesis, the entire nerve, including the endoneurium, perineurium, and epineurium, is completely severed. Neurotmesis leads to disruption of the axon, myelin sheath, and connective tissues. The prognosis for spontaneous recovery is poor without surgery.<ref>Kaya Y, Sarikcioglu L. Sir Herbert Seddon (1903-1977) and his classification scheme for peripheral nerve injury. Childs Nerv Syst. 2015 Feb;31(2):177-80. </ref> Sunderland's fifth-degree lesion fits the definition of neurotmesis in the Seddon classification and represents the highest degree of nerve injury, with a complete nerve defect.
-La mancanza dell'informazione della velocità e della posizione mandibolare a livello mesencefalico, infatti, determina una incapacità di coscienza stereognosica in cui il paziente non riconosce la posizione spaziale e temporale della mandibola. La diminuzione del reclutamento delle unità motorie dei muscoli masticatori e non solo del massetere testato con una ovvia diminuzione della forza masticatoria è il risultato di questo danno organico e funzionale. Tutto ciò indica una compromissione del territorio propriocettivo ma non sappiamo se sono stati coinvolti anche le strutture sensitive. Il periodo silente elettrico mostra, invece, un grave ritardo in latenza con un rallentamento della velocità di conduzione nervosa. A concludere il quadro diagnostico neurofisiopatologico è la constatazione che la radice motoria trigeminale di destra ha perso gran parte delle proprie fibre motorie.
+'''Neurapraxia''' is a nerve injury commonly induced by focal demyelination and/or ischemia and is the mildest type of peripheral nerve injury. In neurapraxia, nerve impulse conduction is blocked in the injured area, sensory and motor connection is lost, but all morphologic structures of the nerve stump, including the endoneurium, perineurium, and epineurium, remain intact.
-Da notare, però, che in una condizione clinica così grave assistiamo ad una diminuzione dell'ampiezza della  <sub>b</sub>Root-MEPs ma non una asimmetria di latenza. Questo risultato indica che c'è stato un danno diretto sulle fibre motorie trigeminali dalla compressione del tumore ( assonotmesi) ma non una demielinizzazione (neuroprassia) che avrebbe mostrato un ritardo di latenza sul massetere destro. E' bene descrivere brevemente la definizione di danno neurologico tenendo conto che il corrispettivo del nervo periferico spinale per il sistema nervoso trigeminale corrisponde alla radice trigeminale motoria.
+'''Axonotmesis''' is a relatively more serious type of peripheral nerve injury and is usually caused by crushing, stretching, or percussion. In axonotmesis, the epineurium is intact, while the perineurium and endoneurium may be disrupted. The axon is separated from the soma and the axon and myelin sheath are disrupted. Wallerian degeneration occurs in the axon stump distal to the injury site within 24 to 36 hours after peripheral nerve injury.
-----La '''neurotmesi''' è causata dalla transezione di un nervo ed è il peggior grado di lesione del nervo periferico. Nella neurotmesi, l'intero nervo, compresi l'endoneurio, il perinevrio e l'epinevrio, è completamente reciso. La neurotmesi porta alla rottura dell'assone, della guaina mielinica e dei tessuti connettivi. La prognosi per il recupero spontaneo è infausta senza intervento chirurgico.<ref>Kaya Y, Sarikcioglu L. Sir Herbert Seddon (1903-1977) and his classification scheme for peripheral nerve injury. Childs Nerv Syst. 2015 Feb;31(2):177-80. </ref> La lesione di quinto grado di Sunderland corrisponde alla definizione di neurotmesi nella classificazione di Seddon e rappresenta il più alto grado di lesione nervosa, con un difetto completo del nervo.
-La '''neuroaprassia''' è una lesione nervosa comunemente indotta da demielinizzazione focale e/o ischemia ed è il tipo più lieve di lesione del nervo periferico. Nella neuroaprassia, la conduzione degli impulsi nervosi è bloccata nell'area lesa, la connessione motoria e sensoriale è persa, ma tutte le strutture morfologiche del moncone nervoso, inclusi l'endoneurio, il perinevrio e l'epinevrio, rimangono intatte.
+After neurotmesis, Schwann cells respond adaptively to axonal disruption, transitioning from a highly myelinated state to a dedifferentiated state. De-differentiated Schwann cells engulf axons and myelin debris and form a regenerative pathway for axon outgrowth. Additionally, activated Schwann cells secrete a group of cytokines, including tumor necrosis factor-alpha, interleukin-1 alpha, and leukemia inhibitory factor, to recruit macrophages and facilitate digestion of debris. Schwann cells also secrete a group of neurotrophic factors, including nerve growth factor, brain-derived neurotrophic factor, and glial cell line-derived neurotrophic factor, to encourage neuron survival and axon elongation.<ref>Jessen KR, Mirsky R, Lloyd AC. Schwann Cells: Development and Role in Nerve Repair. Cold Spring Harb Perspect Biol. 2015 May 08;7(7):a020487. </ref><ref>Madduri S, Gander B. Schwann cell delivery of neurotrophic factors for peripheral nerve regeneration. J Peripher Nerv Syst. 2010 Jun;15(2):93-103.</ref><ref>Yi S, Zhang Y, Gu X, Huang L, Zhang K, Qian T, Gu X. Application of stem cells in peripheral nerve regeneration. Burns Trauma. 2020;8:tkaa002</ref>
-L''''assonotmesi''' è un tipo relativamente più grave di lesione del nervo periferico e di solito è causata da schiacciamento, stiramento o percussione. Nell'assonotmesi, l'epinevrio è intatto, mentre il perinevrio e l'endoneurio possono essere interrotti. L'assone viene separato dal soma e l'assone e la guaina mielinica vengono interrotti. La degenerazione walleriana si verifica nel moncone dell'assone distale al sito della lesione entro 24-36 ore dopo la lesione del nervo periferico.
+Needle electromyography (EMG) is the most sensitive electrodiagnostic study for motor axon loss, and low-amplitude motor responses appear with severe injuries. Decrease in motor response amplitude begins around days 2-3 and is complete by day 6. This reflects the fact that neuromuscular junction degeneration precedes axon degeneration and motor responses are dependent on neuromuscular junction transmission.<ref>Ferrante MA. The Assessment and Management of Peripheral Nerve Trauma. Curr Treat Options Neurol. 2018 Jun 01;20(7):25.</ref>
-Dopo la neurotmesi, le cellule di Schwann rispondono in modo adattivo all'interruzione assonale, passando da uno stato altamente mielinizzato a uno stato de-differenziato. Le cellule di Schwann de-differenziate fagocitano assoni e detriti di mielina e formano un percorso di rigenerazione per la crescita degli assoni. Inoltre, le cellule di Schwann attivate secernono un gruppo di citochine, tra cui il fattore di necrosi tumorale-alfa, l'interleuchina-1 alfa e il fattore inibitorio della leucemia, per reclutare i macrofagi e facilitare la digestione dei detriti. Le cellule di Schwann secernono anche un gruppo di fattori neurotrofici, tra cui il fattore di crescita nervoso, il fattore neurotrofico derivato dal cervello e il fattore neurotrofico derivato dalla linea cellulare gliale, per incoraggiare la sopravvivenza dei neuroni e l'allungamento degli assoni.<ref>Jessen KR, Mirsky R, Lloyd AC. Schwann Cells: Development and Role in Nerve Repair. Cold Spring Harb Perspect Biol. 2015 May 08;7(7):a020487. </ref><ref>Madduri S, Gander B. Schwann cell delivery of neurotrophic factors for peripheral nerve regeneration. J Peripher Nerv Syst. 2010 Jun;15(2):93-103.</ref><ref>Yi S, Zhang Y, Gu X, Huang L, Zhang K, Qian T, Gu X. Application of stem cells in peripheral nerve regeneration. Burns Trauma. 2020;8:tkaa002</ref>
+===Appendix===
-L'elettromiografia con ago (EMG) è lo studio elettrodiagnostico più sensibile per la perdita dell'assone motorio e, con lesioni di grande gravità, compaiono risposte motorie di bassa ampiezza. Il decremento dell'ampiezza della risposta motoria inizia intorno ai giorni 2-3 ed è completo entro il giorno 6. Ciò riflette il fatto che la degenerazione della giunzione neuromuscolare precede la degenerazione degli assoni e le risposte motorie dipendono dalla trasmissione della giunzione neuromuscolare.<ref>Ferrante MA. The Assessment and Management of Peripheral Nerve Trauma. Curr Treat Options Neurol. 2018 Jun 01;20(7):25.</ref>
-=== Appendice ===
+Patient treated by a dental colleague for a prosthetic rehabilitation following postural methods which indicated the best Centric occlusion through dynamometric platforms. The patient came to our observation presenting a clinical state of fasciculation of the masseter muscles as well as, obviously, an occlusal and masticatory discomfort. The centric position finalized by the colleague was, therefore, correlated with the best postural dynamometry response but unfortunately this did not result.
-Paziente trattata da collega odontoiatrico per una riabilitazione protesica seguendo metodiche posturali che attraverso pedane dinamomentriche indicavano la migliore occlusione Centrica. La paziente giunse alla nostra osservazione presentando uno stato clinico di fasciolazione dei muscoli masseteri oltre, ovviamente, un discomfort occlusale e masticatorio. La posizione centrica finalizzata dal collega era, perciò, correlata con la migliore risposta dinamometria posturale ma purtroppo così non é risultato.
-Osservando le figure 4,5 e 6 possiamo comprendere come si costruiscono assiomi che non rispondono ad un criterio scientifico convalidato tanto meno ad una realtà biologica Pensare che un fenomeno a distanza come la stabilità posturale dettata da una pedana dinamometria possa convalidare la scelta di una posizione occlusale spaziale raggiunta manualmente dall'operatore si infrange sulla constatazione che osservando lo stato di sistema trigeminale misurandolo attraverso un demand ( <sub>b</sub>Root-MEPs) il sistema risponde con una propria posizione spaziale non dettata ne dalla correlazione posturologica ne tanto meno dalle manovre manuali dell'operatore bensì da una proprio risultato vettoriale neuromotorio.
+Observing figures 5,6 and 7 we can understand how axioms are built that do not respond to a validated scientific criterion, much less to a biological reality. Thinking that a remote phenomenon such as postural stability dictated by a dynamometric platform can validate the choice of a position occlusal achieved manually by the operator breaks down on the observation that by observing the state of the trigeminal system by measuring it through a demand (<sub>b</sub>Root-MEPs) the system responds with its own spatial position not dictated by posturological correlation nor by the manual maneuvers of the operator but by its own vectorial neuromotor result.<center>
+<gallery widths="260" heights="300" perrow="3" slideshow""="">
-<center>
+File:Pz.posture.png|'''Figure 5:''' Rehabilitated patient following posturological indications from dynamometry data.
-<gallery widths="340" heights="300" perrow="3" slideshow""="">
+File:Pre Root-MEPs.jpeg|'''Figure 6:''' Centric occlusion defined through data indications of the dynamometric platform.
-File:Pz.posture.png|'''Figura 5:''' Paziente riabilitata seguendo le indicazioni posturologiche da dati dinamometria.
+File:Post Root-MEPs.jpeg|'''Figure 7:''' Centric position resulting from bRoot-MEPs. Note the retrusion of at least 3mm and the leftward displacement of the mandible.
-File:Pre Root-MEPs.jpeg|'''Figura 6:''' Occlusione Centrica definita attraverso indicazioni dei dati della pedana dinamometrica.
-File:Post Root-MEPs.jpeg|'''Figura 7:''' Posizione Centrica risultante dalla <sub>b</sub>Root-MEPs. Si noti la retrusione di almeno 3 mm e lo spostamento verso sinistra della mandibola
 </gallery>
-</center>{{Q2|In conclusione la correlazione tra sistema vestibolare e trigeminale benché presente da un punto di vista neurofisiopatologico dovrebbe non essere considerata procedura clinica nelle riabilitatazioni masticatorie.|….dovrebbe esclusivamente essere considerata come campo esplorativo sperimentale per dedurre conoscenze maggiori sulla connettivitá neuronale.}}
+</center>
+{{Q2|In conclusion, the correlation between the vestibular and trigeminal systems, although present from a neurophysiopathological point of view, should not be considered a clinical procedure in masticatory rehabilitation.|….should only be considered as an experimental exploratory field to deduce more knowledge on neuronal connectivity.}}