I. Experimental Approach and Histological Criteria for Evaluating Drug Effects

Abstract

The rationale and methodology for transtympanic drug injection have been established. By the use of phase contrast and Normarski differential interference contrast microscopy to study “surface preparations” of both cochlear and vestibular sensory structures, the degenerative cellular changes which resulted from the localized administration of aminoglycoside antibiotics have been examined toward the selection of an anatomical criterion for the measurement of ototoxicity. The “collapse” cell has been selected for this purpose because of its positive identification, persistence and inability to recover.