Figure 3

Pathologic alterations in the cochlea. (A-C) Cochleae of uninfected control animals showed an intact cochlear architecture (A, B) with a patent scala tympani (+) and (C) a dense population of neurons in the spiral ganglion. In infected animals that were treated with ceftriaxone and placebo, (D and E) dense fibrocytic occlusion of the scala tympani (+) was observed, (E) the organ of Corti (→) appeared destroyed, and (F) neuronal densities were decreased. Adjunctive treatment with (G, H, and I) dexamethasone or (K, L, and M) NT-3 did not lead to significant changes in (G, H, K, and L) fibrocytic cochlear occlusion or damage to hair cells but (I and M) both therapies rescued neuronal ganglion cells from death, reflected in less neuronal loss. The morphology of the cochlea did not differ between animals treated with dexamethasone or NT-3. Staining was performed with hematoxylin and eosin.