The effects of thiamine on abnormal brainstem auditory evoked potentials
Derrick Lonsdale, M.D.
Department of Pediatrics and Adolescent Medicine
Richard H. Nodar, Ph.D.
Department of Otolaryngology and Communicative Disorders
James P. Orlowski, M.D.
Diuison of Anesthesiology, Department of Pediatrics and Adolescent Medicine, Pediatrics and Surgical Intensive Care
The measurement of brainstem auditory evoked potentials (BAEP) has added further sophistication to the study and localization of lesions within the auditory nervous system and the brainstem.
The technique of BAEP testing has been applied successfully in the assessment of the auditory nervous system extending from the eighth nerve to levels just above the midbrain. It has been used for ascertaining hearing thresholds in infants1 and for determining the site of lesions at the level of the eighth nerve and brainstem.2 The response is characterized by seven distinct peaks, each of which is thought to represent a level along the auditory pathway.3 Peak I is considered to be generated by the eighth nerve and Peak II by the cochlear nucleus, both on the ipsilateral side of the test ear. Peaks III through VII are believed to represent levels contralateral to the stimulated ear. Peak III represents the superior olivary complex; Peak IV, the nucleus of the lateral lemniscus; Peak V, the inferior colliculus; Peak VI, the medial geniculates; and Peak VII, the cortical radiations. Some investigators have interpreted the responses more broadly, relating Peak I to the eighth nerve, Peak III to the level of the pons, and Peak V to the midbrain. Results of such tests have been shown to be remarkably reproducible, with the exception of a group of patients with multiple sclerosis.4 We have used seven criteria for evaluating BAEP test results.5
Two infants with recurrent episodes of life-threatening apnea had abnormal BAEP test results. One of . . .