The clinical significance of findings obtained on 3D-FLAIR MR imaging in patients with Ramsay-Hunt syndrome.

Abstract

To investigate the clinical significance of three-dimensional-fluid-attenuated inversion recovery (3D-FLAIR) magnetic resonance imaging (MRI) findings in patients with Ramsay-Hunt syndrome (RHS). Case series. We enrolled 28 consecutive patients of RHS with temporal bone MRI. Initial clinical findings and outcome were assessed by House-Brackmann (HB) scales, electroneuronography (ENoG), and pure tone audiometry (PTA). Two radiologists evaluated the presence of abnormalities on pre-/postcontrast 3D-FLAIR for the cranial nerve (CN)-VII, CN-VIII, inner ear (IE), and the posterior fossa by consensus. The relative signal intensity and enhancement degree (rED) of the structures were measured using ImageJ (http://rsbweb.nih.gov/ij/). Statistical test correlated the clinical symptoms and the outcome with the analysis results of 3D-FLAIR images. 3D-FLAIR demonstrated enhancement of CN-VII in all patients. Precontrast hyperintensity and enhancement were seen in eight and 16 patients with IE, and in four and six with CN-VIII, respectively. Precontrast hyperintensity of IE or CN-VIII was significantly associated with the presence of vertigo (P value < 0.05). Precontrast hyperintensity of IE or CN-VIII significantly correlated with clinical symptoms assessed by HB, ENoG, and PTA (P value < 0.05, respectively). rED of the vestibule moderately correlated with initial HB scale (r = 0.391, P = 0.039). There was no correlation between any of the 3D-FLAIR findings and the follow-up HB. RHS shows frequent abnormalities of IE or CN-VIII, as well as CN-VII on pre-/postcontrast 3D-FLAIR images. Precontrast hyperintensity of IE/CN-VIII on 3D-FLAIR is significantly correlated with the severity of facial palsy, the presence of vertigo, and the degree of hearing impairment but not with clinical outcome.