American Journal of Neuroradiology 2008;29:1363.
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American Journal of Neuroradiology
DOI 10.3174/ajnr.A1100
HEAD & NECK
Comparison of Echo-Planar Diffusion-Weighted Imaging and Delayed Postcontrast T1-Weighted MR Imaging for the Detection of Residual Cholesteatoma
From the Ear, Nose, and Throat Department (F.V., M.M., A.U.), University Hospital Gui de Chauliac, Montpellier, France; INSERM U583–Institute for Neurosciences in Montpellier (F.V., M.M., A.U.), Montpellier, France; and Neuroradiology Department (A.B., V.P.), University Hospital Gui de Chauliac, Montpellier, France.
Please address correspondence to Frederic Venail, MD, Service ORL B, CHU Gui de Chauliac, 80 Avenue Augustin Fliche, 34295 Montpellier, France; e-mail: f-venail{at}chu-montpellier.fr
BACKGROUND AND PURPOSE: Echo-planar diffusion-weighted imaging (DWI) and delayed postcontrast T1-weighted MR imaging (DPI) have been proposed in previous studies to detect residual middle ear cholesteatomas, with varying results. We assessed and compared these 2 techniques in patients with canal wall-up tympanoplasty.
MATERIALS AND METHODS: This was a prospective cohort study. Patients who underwent surgery for middle ear cholesteatoma had CT scanning 9 months after the surgery. If opacity was observed (64%) on CT scans, DWI and DPI were performed before second-look surgery. CT, MR imaging, and surgical data were available for 31 patients. Charts were reviewed independently by 3 blinded examiners. Interobserver agreement for MR imaging was calculated (Cohen 
). Sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) were calculated for these techniques: 1) alone or in association, and 2) according to the residual cholesteatoma size measured during surgery.
RESULTS: Interobserver agreement was better for DWI ( = 0.81) than for DPI ( = 0.51). Sensitivity, specificity, PPV, and NPV values were 60%, 72.73%, 80%, and 50%, respectively, with DWI; and 90%, 54.55%, 78.26%, and 75%, respectively, with DPI. With cholesteatomas >5 mm, the sensitivity and specificity of DWI reached 100% and 88%, respectively, with values for DPI reaching 100% and 80%, respectively. The association of both techniques only allowed improvements in the specificity for lesions >5 mm.
CONCLUSIONS: Both techniques gave acceptable results for residual cholesteatoma detection. DWI is more specific but less sensitive than DPI. Their concurrent use may benefit patients by avoiding undue surgery.