Magnetic resonance examination of the inner ear and cerebellopontine angle in patients with vertigo and/or abnormal findings at vestibular testing.

The inner ears of 167 patients with vertigo and/or abnormal findings at vestibular testing were studied using magnetic resonance (MR). Pathology potentially explaining vertigo was found in 54 patients, and was detected in the posterior fossa (28%), the internal auditory canal (28%) and the membranous labyrinth (44%). The overall percentage of pathology and the percentage of pathology found in the membranous labyrinth was high and was probably influenced by the referral pattern in our hospital where high resolution MR of the inner ear (three dimensional Fourier transformation-constructive interference in steady state sequence; 3DFT-CISS sequence) is available. Unenhanced, and especially gadolinium (Gd)-enhanced T1-weighted spin-echo images, are needed to detect most of the pathology inside the internal auditory canal, and some of the lesions inside the membranous labyrinth. 3DFT-CISS images are the only images that can show fibrous obliteration of the intralabyrinthine fluid spaces, and are therefore necessary to recognise most of the intralabyrinthine pathology. Finally, T2-weighted spin-echo images are best suited to demonstrate cerebellar or brain stem infarction. An additional MR-angiography sequence (three dimensional Fourier transformation-fast imaging with steady precession; 3DFT-FISP) is used when vascular compression of the cochleovestibular nerve is suspected. MR is the method of choice to look for pathology in patients with vertigo, and allows detection of pathology that remains invisible with other imaging techniques. However, well adapted sequences are needed to detect these lesions.