1. The effect of superior canal dehiscence size and location on audiometric measurements, vestibular-evoked myogenic potentials and video-head impulse testing
- Author
-
Angelo Ghidini, Cristina Brandolini, Gian Gaetano Ferri, Andrea Castellucci, Gianluca Piras, Valeria Del Vecchio, Vincenzo Maiolo, Francesco Maria Crocetta, Castellucci, A., Piras, G., Del Vecchio, V., Crocetta, F. M., Maiolo, V., Ferri, G. G., Ghidini, A., Brandolini, C., Castellucci A., Piras G., Del Vecchio V., Crocetta F.M., Maiolo V., Ferri G.G., Ghidini A., and Brandolini C.
- Subjects
medicine.medical_specialty ,Endolymph ,Vestibular evoked myogenic potential ,Semicircular Canal ,Dehiscence ,Superior canal dehiscence ,03 medical and health sciences ,0302 clinical medicine ,Air–bone gap ,Audiometry ,Dehiscence size ,Retrospective Studie ,Ophthalmology ,medicine ,otorhinolaryngologic diseases ,Humans ,Video head impulse test ,030223 otorhinolaryngology ,Retrospective Studies ,medicine.diagnostic_test ,business.industry ,General Medicine ,Reflex, Vestibulo-Ocular ,medicine.disease ,Vestibular Evoked Myogenic Potentials ,Semicircular Canals ,medicine.anatomical_structure ,Otorhinolaryngology ,Corrective saccade ,030220 oncology & carcinogenesis ,Superior petrosal sinus ,Reflex ,Superior petrosal sinu ,sense organs ,business ,Human - Abstract
Purpose: To correlate objective measures of audio-vestibular function with superiorcanaldehiscence (SCD) size and location in ears with SCD and compare results with literature. Methods: We retrospectively evaluated 242 patients exhibiting SCD and/or extremely thinned bone overlying superior canals (SC) on CT scans and selected 73 SCD patients (95 ears with SCD). Data concerning audiometry, impedance audiometry, video-head impulse test (vHIT), cervical vestibular-evoked myogenic potentials (cVEMPs) and ocular VEMPs (oVEMPs) to air- (AC) and bone-conducted (BC) stimuli were collected for each pathologic ear and correlated with dehiscence size and location. Results: AC pure-tone average (PTA) (p = 0.013), low-frequency air–bone gap (ABG) (p < 0.001), AC cVEMPs amplitude (p = 0.002), BC cVEMPs amplitude (p < 0.001) and both AC and BC oVEMPs amplitude (p < 0.001) positively correlated with increasing SCD size. An inverse relationship between dehiscence length and both AC cVEMPs and oVEMPs thresholds (p < 0.001) and SC vestibulo–ocular reflex (VOR) gain (p < 0.001) was observed. Dehiscences at the arcuate eminence (AE) exhibited lower SC VOR gains compared to SCD along the ampullary arm (p = 0.008) and less impaired BC thresholds than dehiscences at the superior petrosal sinus (p = 0.04). Conclusion: We confirmed that SCD size affects AC PTA, ABG and both amplitudes and thresholds of cVEMPs and oVEMPs. We also described a tendency for SC function to impair with increasing SCD size and when dehiscence is located at the AE. The latter data may be explained either by a spontaneous canal plugging exerted by middle fossa dura or by a dissipation through the dehiscence of mechanical energy conveyed to the endolymph during high-frequency impulses.
- Published
- 2021