Atypical Presentation of Medullary Syndrome in a Young Woman

Wallenburg syndrome occurs due to damage to lateral segment of the medulla. Medial medullarysyndrome occurs due to damage to upper portion of the medulla. I report a case of a 30 years old woman diagnosed with medullary syndrome[both medial & lateral features] in absence of CT scan findings sent to the department of Physiology for electrophysiological tests like nerve conduction studies, blink reflex, brainstem auditory evoked potential (BERA) & visual evoked potential (VEP). She had loss of sensations on the ipsilateral half of face (right), hemisensory loss on contralateral trunk & extremities, headache, contralateral hemiparesis (left), ipsilateral lingual paresis with atrophy, fibrillations with contralateral positive Babinski’s sign. The electrophysiological tests showed decrease in conduction velocity of right facial nerve, left tibial & peroneal nerves with decreased amplitude. The nerve conduction studies of median nerve (both motor & sensory) were normal. In blink reflex, latency of R2 ipsilateral & R2 contralateral of supraorbital nerves were increased on right side. There were increasedlatencies of waves II, III, IV & V of BERA & increased P100 latencies in VEP.The results of the electrophysiological tests of the patient showed that she had features of both medial & lateral medullary syndrome suggesting a lesion of both upper & middle medulla. The CT scan in this case was normal but conduction of MRI & CT guided angiography of posterior cerebral & vertebral arteries could have further localized the lesion causing this mixed symptomology

Contralateral blink reflex abnormality in right trigeminal neuralgia: A case report

@#Trigeminal neuralgia can be a manifestation of contralateral cerebellopontine angle tumor. We report here a 34 year old female patient who presented with right sided facial pain in first and second divison of right trigeminal nerve but her blink reflex was abnormal on the left side. Her brain MRI revealed a left cerebellopontine angle tumor displacing the pons as well as the basilar artery. The distortion and displacement of brainstem and the basilar artery contribute to the genesis of the trigeminal neuralgia contralaterally

Application of Blink Reflex and Brainstem Auditory Evoked Potential in Brain Stem Function Evaluation of Patients with Consciousness Disorder / 中国康复理论与实践

@#Objective To explore the characteristics of blink reflex (BR) and brainstem auditory evoked potential (BAEP) in patients with consciousness disorder and the role of BR and BAEP in the evaluation of brain stem function. Methods From January to December, 2015, 31 patients with consciousness disorder were examined with BAEP, BR and Glasgow Coma Scale (GCS), and the outcome was record-ed one month after examination. Results BAEP and BR were positively related with GCS score (r≥0.562, P<0.05) and outcome (χ2=9.644, P<0.01). Conclusion Both BR and BAEP can reflect the brain stem function and respective pathway. Their combination could provide ob-jective basis for prognosis evaluation.

Application of Blink Reflex and Brainstem Auditory Evoked Potential in Brain Stem Function Evaluation of Patients with Consciousness Disorder / 中国康复理论与实践

@#Objective To explore the characteristics of blink reflex (BR) and brainstem auditory evoked potential (BAEP) in patients with consciousness disorder and the role of BR and BAEP in the evaluation of brain stem function. Methods From January to December, 2015, 31 patients with consciousness disorder were examined with BAEP, BR and Glasgow Coma Scale (GCS), and the outcome was record-ed one month after examination. Results BAEP and BR were positively related with GCS score (r≥0.562, P<0.05) and outcome (χ2=9.644, P<0.01). Conclusion Both BR and BAEP can reflect the brain stem function and respective pathway. Their combination could provide ob-jective basis for prognosis evaluation.

Facial nerve decompression in treatment of patients with early peripheral traumatic facial paralysis / 局解手术学杂志

Objective To explore the effect of facial nerve decompression via mastoid-epitypanum approach on the treatment of early peripheral traumatic facial paralysis caused by temporal bone fracture.Methods The data of 21 patients with early peripheral traumatic facial paralysis caused by temporal bone fracture in our hospital from October 2011 to June 2016.The facial nerve electrogram and the blink reflex of the injured facial nerve of 21 patients who treated facial nerve decompression via mastoid-epitypanum approach were compared before and after operation.The degree of facial nerve function recovery was evluated by H-B grading method.Results The facial nerve function of all patients had improved in different degrees,85.7% patients recovered to Ⅰ~Ⅱ level.Compared with those before operation,the latency,amplitude and latent period of blink reflex of the ipsilateral facial electroneurography were significantly improved(P<0.05).Conclusion The facial nerve decompression has good effect in the treatment of early peripheral traumatic facial paralysis.

Efficacy Comparison Between Heat-sensitive Moxibustion and Ginger-partition Moxibustion for Refractory Peripheral Facial Paralysis / 广州中医药大学学报

Objective To compare the effects of heat-sensitive moxibustion and ginger-partition moxibustion on refractory peripheral facial paralysis. Methods Fifty-five patients with refractory peripheral facial paralysis were randomized into heat-sensitive moxibustion group (N=28) and ginger-partition moxibustion group (N=27). For two cases dropped out during the treatment, a total of 25 cases were finally enrolled into the ginger-partition moxibustion group. Two groups received oral use of mecobalamin tablets and conventional acupuncture, and heat-sensitive moxibustion group was given heat-sensitive moxibustion and ginger-partition moxibustion group was given ginger-partition moxibustion additionally. The moxibustion was performed once a day and ten times constituted one course, the treatment covered 6 courses. The clinical effect of the two groups was evaluated by 40-score method, House-Brackmann facial neurological function evaluation standard, blink reflex ( BR) , electromyogram and electroneurography. Results ( 1) Symptoms integral was increased in both groups after treatment ( P0.05). Conclusion The curative effect of heat-sensitive moxibustion for the treatment of refractory peripheral facial paralysis is better than that of ginger-partition moxibustion.

Systematic analysis of the nociceptive blink reflex: reliability and association with psychological factors / Análise sistemática do reflexo de piscar nociceptivo: confiabilidade e associação com fatores psicológicos

The present study aimed to estimate the reliability of the nociceptive blink reflex (nBR) and to evaluate the possible association between the nBR and various pain-related psychological measures: the Anxiety Sensitivity Index-3 (ASI-3), the Fear of Pain Questionnaire III (FPQ-III), the Pain Vigilance and Awareness Questionnaire (PVAQ), the Somatosensory Amplification Scale (SSAS), the Pain Catastrophizing Scale (PCS) and the Situational Pain Catastrophizing Scale (S-PCS). Twenty-one healthy participants were evaluated in two sessions. The nBR was elicited by a so-called "nociceptive-specific" electrode placed over the entry zone of the right supraorbital (V1R), infraorbital (V2R) and the mental (V3R) nerve and left infraorbital (V2L) nerve. The outcomes were: (a) individual electrical sensory (I0) and pain thresholds (IP); b) root mean square (RMS), area-under-thecurve (AUC) and onset latencies of R2 responses; and c) stimulus-evoked pain on a 0-10 numerical rating scale. The questionnaires ASI-3, FPQ-III, PVAQ, SSAS, PCS and S-PCS were also applied. Intraclass Correlation Coefficients (ICCs) and Kappa statistics were computed as a measure of the reliability (α=5%). Besides, Pearson correlation coefficient was used to associate the average of nBR measurements among all sites and the questionnaires. The significance level was set up after a Bonferroni correction (adjusted α=0.8%). ICCs were fair to excellent in 82% of the psychophysical measures and in 86% of V1R, V2R and V2L nBR parameters, whereas the V3R showed poor reliability in 52%. ICCs for intrarater reliability were fair to excellent in 70% of measurements (V3R showed the lowest values) and in 75% of interrater measurements. All kappa values showed at least fair agreement and the majority of the nBR measures (93%) were considered to have moderate to excellent reliability. There was no correlation for any pair of variables considering the adjusted significance level (p>0.008) and only a single significant correlation considering the standard significance level (p < 0.05), where the pain intensity (NRS) at 50% of IP presented a positive and small to moderate correlation with the PCS (r = 0.43, p = 0.047). The nBR and its associated psychophysical measures can be considered a sufficiently reliable test to assess the trigeminal nociceptive function. On the other hand, it seems not associated with psychological factors in healthy participants.

O presente estudo teve como objetivo estimar a confiabilidade do reflexo de piscar nociceptivo (nBR, sigla em inglês) e avaliar a possível associação entre o nBR e várias medidas psicológicas relacionadas à dor: o Anxiety Sensitivity Index-3 (ASI-3), o Fear of Pain Questionnaire III (FPQ-III), o Pain Vigilance and Awareness Questionnaire (PVAQ), o Somatosensory Amplification Scale (SSAS), o Pain Catastrophizing Scale (PCS) e o Situational Pain Catastrophizing Scale (S-PCS) (siglas e nomes em inglês). Vinte e um participantes saudáveis foram avaliados em 2 sessões. O nBR foi estimulado por meio de um eletrodo "nociceptivo específico" posicionado na zona de entrada do nervo supraorbital direito (V1D, sigla em inglês), infraorbital direito (V2D) e esquerdo (V2E) e mentual direito (V3R). As variáveis analisadas foram: a) limar elétrico sensorial (I0) e doloroso (IP); b) raíz quadrática média (RMS, sigla em inglês), área sobre a curva (AUC, sigla em inglês) e as latências da respostas R2; e c) dor provocada pelo estímulo em uma escala numérica de O a 10. Os questionários ASI-3, FPQ-III, PVAQ, SSAS, PCS e S-PCS também foram aplicados. Coeficiente de Correlação Intraclasse (ICC, sigla em inglês) e estatística Kappa foram calculados como medidas da confiabilidade (α=5%). Além disso, coeficiente de correlação de Pearson foi usado para associar a média do nBR entre todos os sítios de avaliação e os questionários. O nível de significância foi ajustado após correção de Bonferroni (α ajustado=0.8%). ICCs foram razoáveis à excelentes em 82% das medidas psicofísicas e em 86% dos parâmetros do nBR em V1D, V2D e V2E, enquanto que 52% das medidas em V3D apresentaram pobre confiabilidade. ICCs para confiabilidade intra-examinador foram razoáveis à excelente em 70% das medições (V3D apresentou os menores valores) e em 75% das medidas inter-examinadores. Todos os coeficientes Kappa apresentaram pelo menos razoável concordância e a maioria das medidas do nBR (93%) foram consideradas moderadas à excelente em termos de confiabilidade. Não houve correlação para nenhum par de variáveis considerando os valores ajustados de significância (p>0,008) e somente foi constatada uma correlação significante considerando o nível de significância padrão (p<0,005), em que a intensidade de dor em 50% do IP apresentou uma correlação positiva entre pequena e moderada com o PCS. O nBR e suas medidas psicofísicas associadas pode ser considerado um teste com suficiente confiabilidade para avaliar a função nociceptiva trigeminal. Por outro lado, parece que o nBR não está associado com fatores psicológicos em participantes saudáveis.

Relationship among Characteristic of Blink Reflex, Facial Nerve Electroneurography and Functional Lesion at the Early Stage of Bell's Palsy / 中国康复理论与实践

@#Objective To investigate the relationship among blink reflex, facial nerve electroneurography and functional lesion at the early stage of Bell's palsy. Methods Blink reflex and electroneurography of facial nerve were performed in 25 patients with early Bell's palsy.They were divided into mild to moderate damage and severe damage according to the result. They were evaluated by House-Blackmann (H-B) scale and were identified: grade I, normal; grade II-III, mild-moderate facial paralysis; grade IV-VI, severe facial paralysis. Results The positive rate of blink reflex was 100%, with the proportion of mild- moderate damage was 28% and severe damage was 72%. H-B scale evaluation showed the percentage of mild-moderate facial paralysis was 44%, severe facial paralysis was 56%, which was consistent with blink reflex (P>0.05). The positive rate of electroneurography was 52%, with the proportion of mild- moderate damage was 44% and severe damage was 8%, which was inconsistent with H-B scale evaluation (P<0.05). Conclusion Blink reflex is preferable to electroneurography in evaluating facial paralysis degree at the early stage of Bell's palsy.

Relationship among Characteristic of Blink Reflex, Facial Nerve Electroneurography and Functional Lesion at the Early Stage of Bell's Palsy / 中国康复理论与实践

Objective To investigate the relationship among blink reflex, facial nerve electroneurography and functional lesion at the ear-ly stage of Bell's palsy. Methods Blink reflex and electroneurography of facial nerve were performed in 25 patients with early Bell's palsy. They were divided into mild to moderate damage and severe damage according to the result. They were evaluated by House-Blackmann (H-B) scale and were identified:grade I, normal;grade II-III, mild-moderate facial paralysis;grade IV-VI, severe facial paralysis. Results The positive rate of blink reflex was 100%, with the proportion of mild-moderate damage was 28%and severe damage was 72%. H-B scale evaluation showed the percentage of mild-moderate facial paralysis was 44%, severe facial paralysis was 56%, which was consistent with blink reflex (P>0.05). The positive rate of electroneurography was 52%, with the proportion of mild-moderate damage was 44%and severe damage was 8%, which was inconsistent with H-B scale evaluation (P<0.05). Conclusion Blink reflex is preferable to electroneurography in evaluating facial paralysis degree at the early stage of Bell's palsy.

The blink reflex test does not show abnormalities in a large group of patients with chronic migraine / O teste do reflexo do piscamento nao mostra alteracoes em um grande grupo de pacientes com enxaqueca cronica

The blink reflex – a simple, non-invasive and inexpensive test – may be indicative of lesions or dysfunctions of the brainstem, and particularly assesses the trigeminal-facial arch. Results from alterations of the blink reflex in patients with headaches have provided controversial data. Method Registration of the waves R1 and R2 (ipsilateral to the stimulus) and R2c (contralateral to the stimulus) by electroneuromyography. Results A large number of controls (n=160) and patients with chronic migraine (n=160) were studied. No significant differences were observed between the two groups. Conclusion It is possible that this relatively simple and primitive reflex is not affected unless there is significant damage to the brainstem. .

O reflexo do piscamento é um teste simples, não invasivo de baixo custo que pode direcionar o raciocínio para lesões ou disfunções do traonco cerebral, avaliando particularmente o arco trigêmeo-facial. Resultados de reflexo do piscamento em pacientes com cefaleias têm mostrado dados controversos. Método Registro das ondas R1 e R2 (ipsilaterais ao estímulo) e R2c (contralateral ao estímulo) por eletroneuromiografia. Resultados Um grande número de controles (n=160) e pacientes com enxaqueca crônica (n=160) foi avaliado. Não foram encontradas diferenças significativas no reflexo do piscamento entre os dois grupos. Conclusão É possível que este reflexo, por ser relativamente simples e primitivo, não esteja alterado a menos que ocorram danos significativos no tronco cerebral. .

Habituation of the blink reflex in the neonatal period and development of auditory processing / Habituação do reflexo cócleo-palpebral no período neonatal e desenvolvimento auditivo

Objective: To verify the existence of an association between the presence/absence of the blink reflex habituation in the neonatal period as well as the auditory processing development. Methods: The occurrence of blink reflex habituation was studied in 33 neurologically normal neonates, who had their behavioral responses analyzed and classified according to Azevedo (1993), between 9 and 25 months of age. Habituation of the blink reflex was verified using a sound stimulus of nearly 90 dB. The stage of the auditory processing development was evaluated through a sound stimulus of nearly 41 dB. Statistical data were analyzed with Fischer and X2 tests. Results: Out of the 33 studied children, 22 presented blink reflex habituation in the first stage of the study. In 7 of them, the auditory processing stage matched their chronological age, while in 15 of them, the auditory processing stage was found inadequate to their chronological age. Eleven children failed to present habituation of the blink reflex in the first stage of the study. From this group, eight children disclosed auditory responses that were adequate to their chronological age and three, inadequate. A statistically significant association between the presence of blink reflex habituation and an auditory processing delay was verified as well as between the absence of the blink reflex habituation and chronologically suitable responses. Conclusions: The presence of blink reflex habituation in the neonatal period does not seem to be a predictive factor of the adequate auditory processing.

Objetivo: Verificar a existência de associação entre presença/ausência de habituação do reflexo cócleo-palpebral no período neonatal bem como o desenvolvimento do processamento auditivo. Métodos: Pesquisou-se a ocorrência de habituação do reflexo cócleo-palpebral em 33 neonatos neurologicamente normais, os quais, entre 9 e 25 meses de idade, tiveram suas respostas comportamentais avaliadas e classificadas segundo Azevedo (1993). A habituação do reflexo cócleo-palpebral foi verificada utilizando-se estímulo sonoro de aproximadamente 90 dB. A etapa do desenvolvimento do processamento auditivo foi avaliada com estímulo sonoro aproximado de 41 dB. A análise estatística dos dados foi realizada por meio dos testes Fischer e X2. Resultados: Das 33 crianças estudadas, 22 evidenciaram habituação do reflexo cócleo-palpebral na primeira etapa do estudo. A etapa do processamento auditivo de 7 delas foi considerada adequada à idade cronológica e de 15 inadequada. Onze crianças não evidenciaram habituação do reflexo cócleo-palpebral na primeira etapa do estudo. Desse grupo, oito crianças manifestaram respostas auditivas adequadas para a idade cronológica e três inadequadas. Verificou-se associação estatisticamente significante entre presença de habituação do reflexo cócleo-palpebral e atraso nas etapas do processamento auditivo, e também entre ausência de habituação do reflexo cócleo-palpebral e respostas adequadas à idade cronológica. Conclusões: A presença de habituação do reflexo cócleo-palpebral no período neonatal parece não ser fator preditivo do adequado desenvolvimento do processamento auditivo.

Evaluation of Trigeminal Nerve Involvement Using Blink Reflex Test in Bell's Palsy

BACKGROUND AND OBJECTIVES: Facial nerve dysfunction in Bell's palsy is evaluated using various parameters including physical examination and electrophysiological studies. Associated symptoms of facial numbness or paresthesia are reported by some patients with Bell's palsy. The aim of this study was to investigate trigeminal nerve involvement in Bell's palsy using blink reflex test. SUBJECTS AND METHODS: Facial nerve and trigeminal nerve functions were assessed using House-Brackmann (HB) grading system, electroneuronography (ENoG) and blink reflex tests in 28 patients diagnosed as Bell's palsy. RESULTS: HB grades correlated with degeneration ratio from ENoG (p=0.002, chi-square test). The ipsilateral R1 reponse of the blink reflex was absent or abnormal in 27/28 patients (96.4%), and ipsilateral R2 response was absent or abnormal in 26/28 patients (92.8%). Contralateral R2 was abnormal in 5/28 patients (17.8%), suggesting involvement of trigeminal nerve in a portion of patients. The results of blink reflex test showed no significant correlation to the outcome of facial nerve function (HB grade) in Bell's palsy patients. CONCLUSIONS: Blink reflex test provides information about trigeminal and facial nerve functions in addition to ENoG results. Our study suggests that subclinical involvement of trigeminal nerve may accompany facial nerve dysfunction in Bell's palsy.

Usefulness of the Blink Reflex Study as a Preoperative Evaluation in the Orbitozygomatic Complex Fracture

PURPOSE: As the evaluation of the preoperative sensibility in the orbitozygomatic complex fracture, used by most surgeons, depends on the patient's subjective judgements, it is difficult to make generalization and to use it as an objective evaluation method. We used the blink reflex study to objectively evaluate injury to the infraorbital nerve. METHODS: From December 2008 to November 2009, a total of 16 patients underwent the patient's subjective report on sensory symptoms and the blink reflex study preoperatively. Among patients having orbitozygomatic complex fracture of type III or more according to Henderson's classification and simultaneously suspected as being injured along the infraorbital nerve pathway, patients who had difficulty in checking preoperative sensibility and said 'normal sensibility' were selected as candidates. RESULTS: Fifteen patients showed abnormal R1 on the fracture side. These results suggested that most of patients had injury to the infraorbital nerve. CONCLUSION: Contrary to the existing tests, the blink reflex study is a useful diagnostic tool in reflecting injury to the infraorbital nerve objectively.

Isolated Trigeminal Neuropathy Caused by Pontine Infarction

No abstract available.

The techniques of studying normal blink reflex / 实用口腔医学杂志

Objective:To investigate the different techniques and wave characteristic of applying non-invasive stimulation in blink reflex.Methods:Thirty volunteers participated in this study.Using the electrodiagnostic techniques,the orbital nerve and mental nerve were stimulated and the waves were respectively recorded at orbicularis oculi and levator labli superioris,then concluded the latency and amplitude of R1,R2,R2'.Results:The results of blink reflex were basically identical with the normative criteria.The wave of stimulating the orbital nerve and recording at levator labli superioris resembled BR.The images were steady and repeatable.The waves of stimulating mental nerve and recording at orbicularis oculi and levator labli superioris were unstable and partial R1 absent.Conclusion:The techniques of stimulating orbital nerve and recording at orbicularis oculi and levator labli superioris are valuable in the initial investigation of trigemino-facial reflex.The techniques of stimulating mental nerve and recording at orbicularis oculi and levator labli superioris can be used to examine assistantly.

A Case of Sequential Multiple Cranial Neuropathies in Diabetes Mellitus

Cranial mononeuropathies, manifesting particulary as opthalmoplegia or facial palsy, are common entities in the dia-betic population. However, sequential multiple cranial neuropathies due to diabetes are much less common. It is often associated with other conditions such as a brain tumor or head trauma. A 61-year-old diabetic man presented with ptosis, opthalmoplegia, and facial palsy which were manifestations of multiple cranial neuropathies involving the left 3rd, 4th, 6th, and 7th cranial nerves throughout five weeks. The pupils were not involved. The neurologic evaluation included a CSF study and a brain MRI with MRA. None of them produced any significant results. Blink reflexes revealed evidence of a left facial nerve lesion. The blood glucose was strictly controlled and steroid therapy was administered. The ptosis of the patientanjx left eyelid improved during treatment and he was discharged after 13 days. In a follow-up examination 3 months after onset, focal neurological deficits including opthalmoplegia and facial palsy on the left side were greatly improved and barely noticeable.

An analysis of the blink reflex measurement in the elderly / 中华老年医学杂志

Objective To obtain the normal value of blink reflex(BR) in the elderly. Methods With clinical electrophysiological diagnostic technique, the orbital nerve was stimulated with electric current to elicit blink reflex in an elderly group (30 subjects, 60 sides) and an adult group (29 subjects, 58 sides). Results For the early response R 1 of BR in the elderly, the latency and amplitude were (10 28?0 39) ms,162 88 ?V. For the late response R 2 and R 2',the latency was (32 86?2 81) ms and (33 33?2 90) ms respectively; the amplitude was 210 72 ?V and 156 32 ?V respectively The difference of the latency between the elderly and adult was statistically significant. Conclusions This study indicates that BR measurement is a simple and harmless technique. The latency of BR was prolonged in the aged.

The Blink Reflex in Diabetic Patients

OBJECTIVE: To assess the facial and trigeminal nerve involvement in diabetic patients using blink reflex study and direct facial motor conduction study. METHOD: The subjects were 397 diabetic patients and 34 normal controls. Diabetic patients were subdivided into two groups based on the findings of nerve conduction studies of limb nerves.: Group I, patients with diabetic polyneuropathy; Group II, patients without diabetic polyneuropathy. The blink reflexes and direct facial motor responses and R1 latency/direct response latency (R/D) ratio were obtained in all the subjects. R1 latency was correlated to the findings of nerve conduction studies of limb nerves. RESULTS: 1) R1 latencies or R2 latencies were abnormally prolonged in 22.4% of Group I, 3.3% of Group II, and direct facial responses were abnormal in 11.8% of Group I, 2% of Group II. 2) There were no significant differences in R/D ratio between the two groups. 3) These findings suggest that not only the facial nerve, but also the trigeminal nerve or brain stem could be affected in diabetic patients with polyneuropathy. CONCLUSION: In diabetic patients, blink reflex can provide useful information in determining the degree and distribution of cranial nerve and brain stem lesions.

Clinical Significance of the R3 Response of the Blink Reflex in Medullar and Cervical Spinal Cord Lesions

OBJECTIVE: To compare the R3 response of the blink reflex in medullar and spinal cord lesion and to investigate whether the reflex arc of the R3 response descend to the cervical spinal cord or not. METHOD: We have studied 3 patients with medullar lesion and 5 patients with cervical spinal cord or vertebral lesion. Normal ranges of the R3 response refer to the results suggested by Moon et al. RESULTS: In 3 patients with medullar lesion, two patients with lateral medullar lesion showed delayed R3 latency or no evoked potential. Four patients with cervial spinal cord lesion showed no R3 response. In one patient with disc protrusion R3 was normal. CONCLUSION: Our results support the hypothesis that the reflex arc of the R3 response descend to the cervical spinal cord.

Significance of Mento-Blink Reflex Study in Lesion of Inferior Alveolar Nerve

OBJECTIVE: This study was designed to observe how the mento-blink reflex (MBR) study is valuable in evaluating the inferior alveolar nerve injury. METHOD: Eleven patients, suffering from the sensory discomfort after extraction of the third molar, and a control group consisting of 20 healthy individuals participated in the clinical neurosensory test (CNST) and the MBR study. The score of CNST was from 0 (normal) to 5 (worst) according to sensory deficit, and the results of MBR were divided into 3 groups: normal; prolongation of R2 latency; no response. RESULTS: In the control group, R2 latencies of right and left were 31.9+/-6.1 msec and 31.5+/-5.9 msec, respectively with the difference of 1.3+/-0.9 msec. The abnormality in the MBR study in patients was correlated with the subjective sensory symptoms (p=0.017) and the abnormality of MBR response was proportional to the score of the CNST. CONCLUSION: We concluded that the MBR study is a useful diagnostic tool in reflecting the inferior alveolar nerve lesion.