[HRCT and MRI image of bilateral large vestibular aqueduct syndrome].

OBJECTIVE: To explore. HRCT and MRI three-dimensional fast imaging employing steady state ac-quisition(3D-FIESTA) imaging features and clinical characteristics of bilateral large vestibular aqueduct syndrome(LVAS).

METHOD: The imaging and clinical features of 14 cases of bilateral LVAS identified over a 5-year periodwere retrospectively analyzed. All patients underwent HRCT and MRI 3D-FIESTA scanning of head and neck;MRI three dimensional reconstructions of internal acoustical meatus were also completed at the same time.

RESULT: Audiogram showed mild to moderate hearing loss and was progressive. The cut-off values for the coronal midpointand operculum planes on the HRCT scan to diagnose an EVA were 1. 5 mm and 4. 3 mm respectively; the averagevalue was 2. 4 mm. VA expansion degree were not linked to the degree of hearing loss. MRI showed VA andlymph sac abnormalities. Concomitant image finding was cochlear hypoplasia.

CONCLUSION: HRCT and MRI 3D-FI-ESTA are important examinations for accurate diagnosis of LVAS. HRCT can acquire the specific size of reamedVA. MRI and 3D reconstructions of internal acoustical meatus can noninasive show more intuitive display ofLVAS and other inner ear malformations than HRCT.