Figure 11.

Utility of MRI in the evaluation of patients with persistent or recurrent symptoms following primary SCD repair. A 52-year old male patient underwent middle fossa craniotomy and SCD repair with resurfacing technique at the first institution. He initially experienced symptom resolution after surgery, but symptoms of left-sided aural fullness, pulsatile tinnitus, and sound-induced vertigo recurred 2 weeks later. (A) Postoperative (after primary SCD repair) high-resolution CT in the plane of Pöschl shows arcuate eminence defect (bracket) and focal pneumolabyrinth (arrowhead). Malleus indicated with “M.” Note that most SCD repair materials are not radio-opaque. (B) Postoperative T2-weighted MRI in the plane of Pöschl reveals a focal fluid void (arrow) associated with partial plugging of the superior semicircular canal that does not span the entire length of the defect. (C–F) Postoperative (after primary SCD repair) audiometric and vestibular testing. (C) Threshold audiogram reveals supranormal bone conduction thresholds (−10 dB at 250 and 500 Hz) of the left ear. (D) Normal tympanometry bilaterally. (E) Present bilateral acoustic reflexes. (F) cVEMP potentials demonstrate low thresholds of 50, 55, 55, and 65 dB HL in response to 250, 500, 750, and 1,000 Hz tone burst stimuli. The patient underwent revision SCD repair at the second institution with plugging of the superior canal using a transmastoid approach with stable symptom improvement 5 years after surgery.