Middle ear cholesteatoma: non-echo-planar diffusion-weighted MR imaging versus delayed gadolinium-enhanced T1-weighted MR imaging--value in detection.

Abstract

To retrospectively compare non-echo-planar (non-EP) diffusion-weighted (DW) imaging, delayed gadolinium-enhanced T1-weighted magnetic resonance (MR) imaging, and the combination of both techniques in the evaluation of patients with cholesteatoma. This institutional review board-approved study, for which the need to obtain informed consent was waived, included 57 patients clinically suspected of having a middle ear cholesteatoma without a history of surgery and 63 patients imaged before "second-look" surgery. Four blinded radiologists evaluated three sets of MR images: a set of delayed gadolinium-enhanced T1-weighted images, a set of non-EP DW images, and a set of both kinds of images. Overall sensitivity, specificity, negative predictive value (NPV), and positive predictive value (PPV), as well as intra- and interobserver agreement, were assessed and compared among methods. To correct for the correlation between different readings, a generalized estimating equations logistic regression model was fitted. Results were compared with surgical results, which were regarded as the standard of reference. Sensitivity, specificity, NPV, and PPV were significantly different between the three methods (P < .005). Sensitivity and specificity, respectively, were 56.7% and 67.6% with the delayed gadolinium-enhanced T1-weighted images and 82.6% and 87.2% with the non-EP DW images. Sensitivity for the combination of both kinds of images was 84.2%, while specificity was 88.2%. The overall PPV was 88.0% for delayed gadolinium-enhanced T1-weighted images, 96.0% for non-EP DW images, and 96.3%for the combination of both kinds of images. The overall NPV was 27.0% for delayed gadolinium-enhanced T1-weighted images, 56.5% for non-EP DW images, and 59.6% for the combination of both kinds of images. MR imaging for detection of middle ear cholesteatoma can be performed by using non-EP DW imaging sequences alone. Use of the non-EP DW imaging sequence combined with a delayed gadolinium-enhanced T1-weighted sequence yielded no significant increases in sensitivity, specificity, NPV, or PPV over the use of the non-EP DW imaging sequence alone.