title: Magnetic resonance enema vs rectal water-contrast transvaginal sonography in diagnosis of rectosigmoid endometriosis.
abstract: OBJECTIVE
  To compare the accuracy of magnetic resonance enema (MR-e) and rectal water-contrast transvaginal sonography (RWC-TVS) in the diagnosis of rectosigmoid endometriosis.
  
  
  METHODS
  This prospective study included 286 patients of reproductive age with clinical suspicion of rectosigmoid endometriosis. Patients underwent MR-e and RWC-TVS before laparoscopic excision of endometriotic lesions. The findings of MR-e and RWC-TVS were compared with surgical and histological results.
  
  
  RESULTS
  Of the 286 patients included in the study, 151 (52.8%) had rectosigmoid endometriosis. MR-e and RWC-TVS had similar accuracy in the diagnosis of rectosigmoid endometriosis (P = 0.063). In the diagnosis of rectosigmoid endometriosis with MR-e, the sensitivity was 95.4% (95% CI, 90.7-99.1%), specificity was 97.8% (95% CI, 93.6-99.5%), positive predictive value (PPV) was 98.0% (95% CI, 94.1-99.6%), negative predictive value (NPV) was 95.0% (95% CI, 89.9-97.9%), positive likelihood ratio (LR+) was 42.91 (95% CI, 14.01-131.46) and negative likelihood ratio (LR-) was 0.05 (95% CI, 0.02-0.10). For diagnosis with RWC-TVS, sensitivity was 92.7% (95% CI, 87.3-96.3%), specificity was 97.0% (95% CI, 92.6-99.2%), PPV was 97.2% (95% CI, 93.0-99.2%), NPV was 92.3% (95% CI, 86.6-96.1%), LR+ was 31.29 (95% CI, 11.90-82.25) and LR- was 0.08 (95% CI, 0.04-0.13). MR-e and RWC-TVS underestimated the size of the endometriotic nodules; for both imaging techniques the underestimation was greater for nodules with a diameter ≥ 30 mm. There was no significant difference in the mean intensity of pain experienced by the patients during the two examinations.
  
  
  CONCLUSIONS
  RWC-TVS should be the first-line investigation in patients with clinical suspicion of rectosigmoid endometriosis and physicians should be trained in performing this examination. Considering that MR-e is more expensive than RWC-TVS, it should be used only when the findings of RWC-TVS are unclear. Copyright © 2016 ISUOG. Published by John Wiley & Sons Ltd.
authors.affiliation: Academic Unit of Obstetrics and Gynaecology, IRCCS AOU San Martino - IST, Genoa, Italy.|Department of Neurosciences, Rehabilitation, Ophthalmology, Genetics, Maternal and Child Health (DiNOGMI), University of Genoa, Genoa, Italy.
authors.forename: U
authors.initials: U
authors.lastname: Leone Roberti Maggiore
authors.affiliation: Department of Radiology, Galliera Hospital, Genoa, Italy.
authors.forename: E
authors.initials: E
authors.lastname: Biscaldi
authors.affiliation: Department of Surgical and Diagnostic Sciences, IRCCS San Martino Hospital and National Institute for Cancer Research, University of Genoa, Genoa, Italy.
authors.forename: V G
authors.initials: VG
authors.lastname: Vellone
authors.affiliation: Academic Unit of Obstetrics and Gynaecology, IRCCS AOU San Martino - IST, Genoa, Italy.|Department of Neurosciences, Rehabilitation, Ophthalmology, Genetics, Maternal and Child Health (DiNOGMI), University of Genoa, Genoa, Italy.
authors.forename: P L
authors.initials: PL
authors.lastname: Venturini
authors.affiliation: Academic Unit of Obstetrics and Gynaecology, IRCCS AOU San Martino - IST, Genoa, Italy.|Department of Neurosciences, Rehabilitation, Ophthalmology, Genetics, Maternal and Child Health (DiNOGMI), University of Genoa, Genoa, Italy.
authors.forename: S
authors.initials: S
authors.lastname: Ferrero
mesh_terms: D000328:Adult; D003287:Contrast Media; D004715:Endometriosis / Q000000981:diagnostic imaging*; D004733:Enema; D005260:Female; D006801:Humans; D008279:Magnetic Resonance Imaging / Q000379:methods*; D011446:Prospective Studies; D012680:Sensitivity and Specificity; D014463:Ultrasonography / Q000379:methods*; D014621:Vagina / Q000473:pathology*; D014867:Water
chemical_list: D003287:Contrast Media; D014867:Water
keywords: bowel endometriosis; diagnosis; endometriosis; magnetic resonance; transvaginal ultrasonography