OBJECTIVE. The purpose of our study was to determine the efficacy of contrast-en�hanced CT in detecting a thickened endometrium. We used transvaginal sonography as the reference standard.
MATERIALS AND METHODS. Between March 2005 and January 2007, data from 259 patients (mean age, 47 years; age range, 18-90 years) who underwent transvaginal sonog�raphy and contrast-enhanced CT of the pelvis were analyzed retrospectively. The endome�trium was quantitatively measured in millimeters on sonography. On CT it was qualitatively categorized as normal, thickened, indeterminate, or not visualized and compared with the sonography findings and original radiology reports. When the endometrium was indetermi�nate (thickened or triangular in shape on axial images), sagittal reconstructions were per�formed for final categorization. Two reviewers evaluated the CT scans and sonograms jointly with differences resolved by consensus. Kappa, Wilcoxons rank sum test, and intraclass cor�relation statistics were derived.
RESULTS. The overall sensitivity and specificity of CT in detecting the thickened endo�metrium was 53.1% and 93.5%, respectively, relative to transvaginal sonography. The positive and negative predictive values were 66.7% and 89.1%, respectively. Kappa, the statistical measure of agreement between CT and sonography data, was 0.5049. All cases of a triangular endometrium were normal in size on sagittal reconstruction images.
CONCLUSION. Routine pelvic CT correctly identifies a normal endometrium in most patients. Sagittal reconstruction images are helpful to further evaluate the endometrium on CT in cases with a prominent or triangular endometrium because these are often related to uterine version. CT is relatively insensitive in detecting the thickened endometrium but better able to identify gross rather than subtle thickening, which must be further characterized by transvaginal sonography.