MRI SCREENING FOR ACOUSTIC NEUROMA WITHOUT GADOLINIUM - VALUE OF 3DFT-CISS SEQUENCE

To evaluate the efficacy of a gradient-echo sequence (3DFT-CISS) in th e diagnosis of acoustic neuromas, two independent observers twice revi ewed the images of the temporal bones of 83 patients. Contrast-enhance d T1-weighted spin echo images were used as the reference, showing 18 acoustic neuromas, including 5 purely intracanalicular and one intrala byrinthine tumours. High sensitivity (89-94 %), specificity (94-97 %) and accuracy (94-95 %) were found. Intraobserver (kappa 0.93-1) and in terobserver (kappa 0.83-0.84) reproducibility were very good. The smal lest intracanalicular tumour was overlooked twice by both observers; t he intralabyrinthine tumour once by one observer. All tumours were det ected with a less stringent decision criterion, at the expense of lowe r specificity.