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.