MDCT enteroclysis urography with split-bolus technique provides information on ureteral involvement in patients with suspected bowel endometriosis

OBJECTIVE. The objective of our study was to evaluate the accuracy of MDCT enteroclysis with a split-bolus technique in detecting ureteral compression caused by endometriosis in women with suspected bowel endometriosis. SUBJECTS AND METHODS. This prospective study included 103 patients with suspected bowel endometriosis. Examinations were performed on a 16-MDCT scanner; 20% of the IV contrast material was administered during colonic distention and intestinal hypotonization (i.e., 7-8 minutes before starting volumetric acquisition). After injection of the remaining quantity of contrast material, the volumetric acquisition was performed during the portal phase of contrast enhancement. RESULTS. The sensitivity of MDCT enteroclysis urography in identifying bowel nodules was 95.5%; specificity, 97.2%; positive predictive value (PPV), 98.5%; negative predictive value (NPV), 92.1%; accuracy, 96.1%; positive likelihood ratio, 34.39; and negative likelihood ratio, 0.05. The opacification was poor in 8.2% of the ureters, sufficient in 17.4%, and good in 74.4%. One hundred ninety-one ureters (92.3%) were opacified between the crossing of the iliac vessels and the bladder. Compression was observed at MDCT enteroclysis urography in 36 ureters (17.4%); surgery confirmed the presence of ureteral compression in 34 ureters (16.4%). The sensitivity of MDCT enteroclysis urography in identifying ureteral compression was 97.1%; specificity, 98.8%; PPV, 94.4%; NPV, 99.4%; accuracy, 99.0%; positive likelihood ratio, 83.54; and negative likelihood ratio, 0.03. CONCLUSION. MDCT enteroclysis urography allows radiologists to determine whether bowel endometriosis and ureteral compression are present without increasing the radiation dose imparted to the patient.