3CLT ABR analyses in a human subject with unilateral extirpation of the inferior colliculus

• Published in: Hearing research Vol. 72; no. 1; pp. 99 - 107
• Main Authors: Durrant, John D., Martin, William H., Hirsch, Barry, Schwegler, John
• Format: Journal Article
• Language: English
• Published: Amsterdam Elsevier B.V 1994; Elsevier
• Subjects: Adult; Arteriovenous Malformations - surgery; Auditory brainstem response; Auditory pathway; Biological and medical sciences; Brain - surgery; Central auditory pathology; Ear, auditive nerve, cochleovestibular tract, facial nerve: diseases, semeiology; Evoked Potentials, Auditory, Brain Stem; Female; Humans; Inferior Colliculi - injuries; Inferior Colliculi - physiology; Inferior colliculus; Magnetic Resonance Imaging; Medical sciences; Non tumoral diseases; Otorhinolaryngology. Stomatology; Radiosurgery - adverse effects; Stereotactic radiosurgery; Three-channel Lissajous trajectory; Stereotactic radiosurgery; Auditory pathway; Auditory brainstem response; Inferior colliculus; Central auditory pathology; Three-channel Lissajous trajectory; Human; Electrodiagnosis; Nervous system diseases; Colliculus inferior; Brain stem; Surgery; Auditory evoked potential; Central nervous system disease; ENT disease; Lesion; Cerebral disorder
• ISSN: 0378-5955; 1878-5891
• DOI: 10.1016/0378-5955(94)90210-0

Reported are the results of analyses of three-channel Lissajous trajectories (3CLTs) of the auditory brain stem responses (ABRs) in a human subject in whom a focal lesion of the brain stem was caused by stereotactic radiosurgery, the ‘gamma knife’. The surgery caused total destruction of the right inferior colliculus. The results, using multiple measures for defining ABR components, confirm findings from more conventional 2-channel recordings which, in turn, suggested the presence of an intact wave IV but a negligible, if not totally absent, wave V with stimulation of the left (contralateral) ear. The results thus support theories that wave V is generated by crossed pathways and that wave IV is an independent wave generated by the lateral lemniscus. Since magnetic resonance imaging suggested no destruction of tissue below the inferior colliculus, the findings also support theories of wave V generation at or rostral to the inferior colliculus. In practical terms, the results demonstrate the value of multichannel recordings of the ABR in component identification and in interpreting ABR abnormalities.