Longitudinal Cognitive and Neurobehavioral Functional Outcomes Before and After Repairing Otic Capsule Dehiscence

Clinicians managing patients with peripheral vestibular disorders are challenged with signs and symptoms of altered cognitive function, which often introduce challenges when trying to elicit a cogent history. Cognitive alterations seem to be associated with many vestibular asymmetries (1) and with otic capsule defects. Nearly a quarter century ago, Black et al. (2) reported that the majority of patients with perilymph fistula (PLF) experience altered cognitive status. Similar cognitive changes have recently been described in patients with superior semicircular canal dehiscence syndrome (SSCDS) symptoms (3). Video recordings of consenting patients before and after intervention help to further document these obvious alterations in ways that complement standardized neuropsychology testing (4–12). Recently, a prospective cohort of 12 patients with long-term follow-up and with SSCDS, 6 with radiographic evidence of superior canal dehiscence (SCD) treated with a middle fossa approach and plugging; and 6 with no imaging visible otic capsule dehiscence (no-iOCD) treated with round window reinforcement (RWR) was reported (3). It has been suggested that the term SSCDS be replaced with otic capsule dehiscence syndrome (OCDS) because the same SSCDS symptoms and diagnostic findings can occur with lateral and posterior semicircular canal dehiscence, internal carotid artery-cochlea dehiscence, posterior semicircular canal-jugular bulb dehiscence, posttraumatic hypermobile stapes footplate (Dr. Arun Gadre, personal communication, August 1, 2015) and in patients with no-iOCD (3,6,13–17). This study used a battery of neuropsychological tests to provide the first quantitative characterization of the preoperative and postoperative cognitive function changes in patients undergoing surgical management of their OCDS. A comprehensive neuropsychology test battery was administered preoperatively and at 3, 6, 9, and when possible 12 months postoperatively. This battery included: the Beck Depression Inventory-II; the Wide Range Intelligence Test including average verbal (crystallized intelligence) and visual (fluid intelligence); the Wide Range Assessment of Memory and Learning, including the four domains of verbal memory, visual memory, attention/concentration, and working memory; and the Delis–Kaplan Executive Function System (for an in-depth description of these neuropsychology tests, see Supplemental Digital Content) (18–28). These neuropsychological tests showed distinctive patterns that provide greater insight into the nature of the cognitive dysfunction these patients experience and suggest that additional interventions may maximize and/or accelerate their cognitive recovery. These OCDS patients, with two different dehiscence locations and resolved surgically, may provide a novel opportunity to gain deeper insight into cognitive neuroscience.