Differences in Symptoms among Adults with Canal versus Otolith Vestibular Dysfunction: A Preliminary Report

Despite the importance of symptomatology in the diagnosis of vestibular dysfunction, the qualitative nature of the symptoms related to semicircular canal (canal) versus otolith dysfunction is not fully understood. The purpose of this study was to compare symptoms, and their severity, in individuals with canal versus otolith peripheral vestibular dysfunction. A subjective tool, the Descriptive Symptom Index (DSI), was developed to enable categorization of symptoms as rotary, linear, imbalance or falls, and nondistinct. Fourteen adults were recruited and grouped based on vestibular function testing: canal only dysfunction, otolith only dysfunction, or canal and otolith dysfunction. Also, the Dizziness Handicap Inventory (DHI) was used to grade the severity of perceived limitations due to symptoms. The DSI was reliable and differentiated those with canal (rotary symptoms) versus otolith (linear symptoms) dysfunction. Most individuals with otolith only dysfunction did not report rotary symptoms. DHI scores were significantly higher in those with otolith dysfunction, regardless of canal functional status. All who experienced falls had otolith dysfunction andnone had canal only dysfunction. Results support the importance of using linear and rotary descriptors of perceived disorientation as part of diagnosing vestibular dysfunction.