Mondini defect in association with multiple congenital anomalies.

A case of bilaterally symmetrical genetic aplasia conforming to Mondini type of congenital deformity in a 12-day-old child is presented with the help of temporal bone sections. Cochlear changes include a stunted modiolus, deficient interscalar septum between the middle and upper coils forming a scala communis cochleae, a degenerated organ of Corti and reduced spiral ganglion cells and dendrites. The vestibule is malformed, with membranous labyrinth being deficient. The utricle and semicircular canals are absent. There is no oval window or stapedial footplate, and the facial nerve is hypoplastic. An interesting feature is the unusual association of bilateral bony choanal atresia, atrial septal defect, cleft lip, absence of olfactory bulbs in the brain, and congenital ophthalmic anomalies.