Brainstem auditory evoked potentials in tubercular meningitis and their correlation with radiological findings

The present study has been undertaken to describe brainstem auditory evoked potential (BAEP) changes in tubercular meningitis (TBM) and correlate these with CT scan and MRI findings. 24 patients with TBM were subjected to clinical evaluation and CT scan or MRI study. Outcome was defined by 3 month Barthel index score (BI) into poor (BI<12) and good (BI>or=12). The mean age of patients was 26.4+/-14.9 (range 10-62) years, 8 of them were females. Sixteen patients were in stage III, 5 in stage II and 3 in stage I meningitis. CT scan revealed hydrocephalus in 16, exudate in 9, infarction in 12 and tuberculoma in 3 patients. Brainstem was involved in 3 patients (2 infarction and 1 granuloma). BAEPs were unrecordable in one patient and abnormal in 15. The absolute latencies and inter peak latency (IPL) however were not significantly affected. The wave V/I amplitude ratio was abnormal on 12 sides. The BAEP abnormalities were not related to the stage of meningitis, level of consciousness, any specific CT or MRI changes or outcome at 3 months.