Figure 20b. Absent right facial nerve in a 3-year-old cochlear implant candidate with bilateral sensorineural hearing loss and right facial paralysis. (a) On a sagittal 3D fast spin-echo MR image of the right IAC, the right facial nerve is absent (F). Although sensorineural hearing loss was most severe on the right side, the cochlear nerve (C), albeit small, is present. VN = vestibular nerve. (b) Sagittal 3D fast spin-echo MR image demonstrates a normal left IAC. C = cochlear nerve, F = left facial nerve, VN = vestibular nerve.