The incidence and distribution of cupular deposits in the pediatric vestibular labyrinth.

OBJECTIVES: Deposits of basophilic material on the cupulae of the semicircular ducts have been described in adult human temporal bones, and such deposits have been implicated in the clinical phenomenon of benign paroxysmal positional vertigo (BPPV). Although relatively rare, BPPV has been reported to occur in children. The goal of this study was to evaluate the occurrence of cupular deposits in pediatric material.

STUDY DESIGN: Basic science, two-center histopathologic temporal bone study.

METHODS: We examined 186 temporal bones from 121 individuals between the ages of newborn and 10 years. The average age was 14.7 months. All temporal bones were acquired at autopsy, embedded in celloidin, and sectioned for light microscopic study. The cupulae of the semicircular ducts were identified and any deposits found were graded according to their size and position on the cupula.

RESULTS: A total of 276 cupulae were identified, and in 35 (12.7%) of these a basophilic deposit was found. In many cases the deposits contained recognizable otoconial crystals. Most deposits were small and they were almost equally distributed between the three semicircular ducts. However, the lateral and posterior cupulae were somewhat more involved than the superior cupula. Our data showed that cupular deposits are less frequently found in the pediatric labyrinth, compared with adults as reported in previous studies.

CONCLUSIONS: The lower occurrence in children versus adults suggests that the deposits may be a phenomenon of the aging vestibular labyrinth.