Blink Reflex And Brainstem Auditory Evoked Potential In The Diagnosis Of Brainstem Infarction

[Objective] Stroke is the most common neurological disease. The ratio indiagnosis of brainstem infarction can be elevated by MR. But it is hard for MR toreflect the function event in pathological changes. Blink reflex and brainstem auditorycvoked potential are objective-scopy in elevating the function of brainstem. Theycould reflect the variation of the function in brainstem sensitively. Especially for thepatients without brainstem physical signs and could not received the examination ofMR. The site-specific diagnosis in pathological changes can be based on them andcan be good for early diagnosis and treatment.[Materials and Methods] 40 patients proved to be brainstem infarction byMR were investigated. All patients were diagnosed by the criteria proposed in 1995 atthe fourth national cerebrovascular diseases meeting. They had no other infarctionfocuses in their brain, no diabetes and no severity heart, liver and kidney diseases.lnquired and checked the patients groups. Divided the patients into two groupsaccording to the abnormalities localized in brainstem: the symptomatic group and theasymptomatic group. Compared with 40 healthy people. Patients were examined byBR and BAEP respectively. Two different components of BR were recorded, thecariy ipsilateral response (R₁), late ipsilateral response (R₂), and late contralateralresponse (R₂'), calculated the mean incubation period. At the same time observed thewave shape, the peak latency ofâ… ,â…¢,â…¤and the inter- peak latency ofⅠ～Ⅲ,Ⅲ～Ⅴ,Ⅰ～Ⅴin BAEP.[Results] In 40 patients there were 14 patients who had got the symptom ofbrainstem whereas 26 patients had not got. 33 patients were abnormity in BR in groupof brainstem infarction (82.5ï¼…), abnormity in Rl there were 29 patients (72.5ï¼…),in R₂ group there were 20 patients (50ï¼…), in R₂' there were 19 patients (47.5ï¼…). 5patients were reflected of pontine infarction in clinical manifestation, all weredetected abnormality in BR, 4 patients reflected of medulla infarction, one wasnornal, 3 were prolonged. 5 reflected midbrain infarction in clinical manifestationonly 2 were abnormal. 26 patients with no signs of brainstem infarction, 23 patientswere inspected abnormally in BR. In 40 patients of brainstem infarction, theabnormal rate of brainstem injury detected by BR was 71.4ï¼…in brainstemsymptomatic group and 88.5ï¼…in brainstem asyrnptomatic group respectively, thelotal abnormal rate was 82.5ï¼…. According to BAEP, 32 patients (80ï¼…) in 40 patients wave shape was abnormal. 11 patients were abnormal in BAEP among the 14 patientswith symptom or sign of brainstem: 4 patients were abnormal among 5 patientssuspected of pontine infarction, 2 patients were abnormal among 4 patients suspectedof medulla infarction and 4 were abnormal among 5 patients suspected of midbraininfarction. 26 patients without signs of brainstem infarction, 22 patients wereinspected abnormally in BAEP. In 40 patients of brainstem infarction, the abnormalrate of brainstem injury detected by BAEP was 78.57ï¼…in brainstem symptomaticgroup and 84.61ï¼…in brainstem asymptomatic group respectively, the total abnormalrate was 80ï¼…. The combined abnormal rate of BR and BAEP in detecting brainsteminjury was 92.5ï¼….Among 40 patients with brainstem infarction. There is no significant differencebetween prioer-trearment and post-treatment in BR and BAEP in brainstem infarctionpatients.[Conclusion]1. Blink reflex detection: Bainstem infaction group compared with normalgroup, each mean incubation period was prolonged obviously in R₁,R₂,R₂', P＜0.05,there was statistical significance.2. 5 patients were reflected of pontine infarction in clinical manifestation, allwere detected abnormality in BR, 4 patients reflected of medulla infarction, one wasnomal, 3 were prolonged. 5 reflected midbrain infarction in clinical manifestationonly 2 were abnormal. 26 patients with no signs of brainstem infarction, 23 patientswere inspected abnormally in BR.3. BR is a valuable examination and without trauma to brainstem infarction. BRcan reflex the brainstem pathological changes sensitively. BR can provide anobjective reference to clinician. It is a clinical valuable electrophysiologyexamination.4. Brainstem auditory evoked potential detection: Bainstem infaction groupcompared with normal group, the differences were significant in the peak latency ofâ… ,â…¢,â…¤and the inter-peak latency ofⅠ～Ⅲ,Ⅲ～Ⅴ,Ⅰ～Ⅴin BAEP.(P＜0.05).5. In BAEP 5 patients were reflected of pontine infarction in clinicalmanifestation, 4 patients were detected abnormality, 4 patients reflected of medullainfarction two were abnomal, 5 reflected midbrain infarction in clinicalmanifestation four were abnormal. 26 patients with no signs of brainstem infarction,22 patients were inspected abnormally in BAEP6. Both BR and BAEP reflected the foundation of pathology and physiology irom different anatomy pathways in brainstem infarction . They can provide thediagnois of brainstem infarction an addition and conduce, to level diagnosis.7. The combined abnormal rate of BR and BAEP in detecting brainsteminfarction was 92.5ï¼…, the abnormal ratio was higher than detected alone. So weSuggest combined the two detections in clinical work. They would conduce to detectthe tbcal of brainstem.8. The patients of brainstem infarction were dectected by BR and BAEP posttreatment after haif a month. There was no marked change between the prior and thepost treatment. It is derangement between linical manifestation and the recover in BRand BAEP.