Problem Current diagnostic criteria for enlarged vestibular aqueduct (EVA), >1.5mm at the midpoint, was determined in the pre-CT era by Valvassori. Recent research, based on 73 CTs from children with no sensorineural hearing loss (SNHL), suggests new criteria for the diagnosis of EVA—midpoint of >0.9mm or operculum >1.9mm. We evaluated the proposed new radiographic, Cincinnati criteria for the diagnosis of EVA. Methods In a retrospective cohort study, we reviewed temporal bone CT scans of 130 pediatric cochlear implant recipients to measure the vestibular aqueduct midpoint and opercular width and 5 other temporal bone dimensions. Results The Cincinnati criteria identified 44% of patients with EVA versus 16% with the Valvassori criterion (P < 0.01). Of those with EVA, 45% were unilateral and 55% were bilateral using Cincinnati criteria; 64% were unilateral and 36% bilateral using Valvassori criterion (P<0.01). Right and left side measurements of vestibular aqueduct operculum (r=0.67, P<0.01) and midpoint (r=0.58, P<0.01) correlated substantially. The Cincinnati criteria diagnosed 70 ears with EVA classified as normal using the Valvassori criterion (P<0.01). Of these 70 ears, 59 had no other medical explanation for their hearing loss. Conclusion The Cincinnati criteria identified a large percentage of pediatric cochlear implant patients with EVA who otherwise had no known etiology for their deafness. Significant correlations between right and left side measurements suggest that EVA may not be morphologically asymmetric as previously thought. Significance The Cincinnati criteria potentially alters the current estimation of the most common etiologies of bilateral severe-to-profound sensorineural hearing loss in the pediatric population. Support KD is a Doris Duke Clinical Research Fellow, supported by the Doris Duke Foundation.
The Effect of Pulling Out Cochlear Implant Electrodes on Inner Ear Microstructures: A Temporal Bone Study