FIG. 1.

Temporal bone computed tomography scans. A coronal section of subject 7 (p.P542R/+) shows an enlarged vestibule (black arrowhead) and absent superior semicircular canal. An axial section demonstrates severe cochlear hypoplasia (black arrow) and poor mastoid pneumatization (white circle) in addition to enlargement of the vestibular aqueduct (EVA) (white arrow). Examination of adjacent sections confirmed this latter structure as the vestibular aqueduct and not the jugular bulb. Another subject (p.H723R/+) with a typical EVA has a superior semicircular canal (black dotted arrow), relatively normal cochlea, a well-pneumatized and aerated mastoid, and EVA (white arrow).