Accuracy of transvaginal sonography versus magnetic resonance imaging in the diagnosis of rectosigmoid endometriosis: Systematic review and meta-analysis

Abstract

Introduction Intestinal endometriosis is considered the most severe form of deep endometriosis, the rectosigmoid being involved in about 90% of cases of bowel infiltration. Transvaginal sonography (TVS) and magnetic resonance imaging (MRI) have been used for noninvasive diagnosis and preoperative mapping of rectosigmoid endometriosis (RE), but no consensus has been reached so far regarding which method is the most accurate in this setting. Objective We aimed at performing a systematic review and meta-analysis to compare the accuracy of TVS versus MRI in the diagnosis of RE in a same population. Methods A systematic review was conducted in accordance with the PRISMA guidelines. Studies were identified by searching the MEDLINE, Embase, and LILACS databases, as well the reference lists of retrieved articles, through February 2019. We included all cross-sectional studies that evaluated the accuracy of TVS versus MRI in the diagnosis of RE within a same sample of subjects and that used surgical findings with histological confirmation as the gold standard. The QUADAS-2 instrument was used to evaluate study quality. Sensitivity, specificity, positive likelihood ratios (LR+), and negative likelihood ratios (LR-) for the diagnosis of RE were calculated. This study is registered with PROSPERO, number CRD42017064378. Results Eight studies ( n = 1132) were included in the meta-analysis. The pooled sensitivity, specificity, LR+, and LR- values of MRI for RE were 90% (95% CI, 87–92%), 96% (95% CI, 94–97%), 17.26 (95% CI, 3.57–83.50), and 0.15 (95% CI, 0.10–0.23); values of TVS were 90% [95% CI, 87–92%], 96% (95% CI, 94–97%), 20.66 (95% CI, 8.71–49.00) and 0.12 (95% CI, 0.08–0.20), respectively. Areas under the S-ROC curves (AUC) showed no statistically significant differences between MRI (AUC = 0.948) and TVS (AUC = 0.930) in the diagnosis of RE ( P = 0.13). Moreover, considering the average prevalence among the studies of 47.3%, both methods demonstrated similarly high positive post-test probabilities (93.9% for TVS and 94.8% for MRI), and the combined use of them yielded a post-test probability of 99.6%. Conclusion MRI and TVS have similarly high accuracy and positive post-test probabilities in the noninvasive diagnosis of RE. Combination of MRI and TVS may increase even further the positive post-test probabilities to near 100%.

Comparison of physical examination, ultrasound techniques and magnetic resonance imaging for the diagnosis of deep infiltrating endometriosis: A systematic review and meta‑analysis of diagnostic accuracy studies

“…TVUS had a pooled sensitivity and specificity of 76 and 94% with high diagnostic accuracy (AUC =0.92). These findings are in agreement with earlier reviews on the diagnostic accuracy of TVUS, which also indicated the high specificity and high diagnostic accuracy of this technique (AUC >0.90) ( 11 , 46-48 ). However, compared with the previous reviews, a greater number of studies were included in the present analysis.…”

“…To the best of our knowledge, no previous reviews have compared the accuracy of TRUS and TVUS for the diagnosis of DIE. The present study revealed MRI to have lower sensitivity (82%) and specificity (87%) for diagnosis of DIE when compared with the previous reviews of Moura et al (46) and Nisenblat et al (11). Their studies demonstrated ~90% sensitivity and specificity of MRI for diagnosis of DIE.…”

Correlation between findings of nuclear magnetic resonance and 3D anorectal ultrasound in patients with suspected deep endometriosis

“…The specificity of transvaginal USG ranges from 66.7% to 100%, while that of NMR ranges from 50% to 100%. 13 In the present study, 3D anorectal USG had almost perfect agreement, according to the kappa coefficient, when comparing lesions that invade the muscularis propria; however, such expressive agreement values were not observed in patients without lesions or those with lesions in the perirectal fat. In this service, 3D anorectal USG showed a significant correlation in the diagnosis of deep intestinal pelvic endometriosis and involvement of the muscularis propria.…”

“…10 Some studies indicate pelvic ultrasound as a first-line diagnostic test, leaving NMR and endoscopic USG of the rectosigmoid as second and third lines of diagnosis, 12 although some systematic reviews demonstrated that both NMR and transvaginal pelvic USG have similar sensitivity and specificity in the diagnosis of deep endometriosis. 13 Some studies 14 compared the accuracy of two-dimensional vs. three-dimensional USG diagnosis and showed no significant difference between positive and negative predictive values; however, this comparison was made with the use of transvaginal USG rather than rectal USG. 12 Surgical treatment of deep endometriosis involves surgical techniques known as muscle layer dissection (shaving), disc resection, and intestinal resection (segmental or patch).…”

Accuracy of Transvaginal Ultrasonography for Diagnosis of Endometriosis Taking Laparoscopy as Gold Standard

“…18 Another systematic review compared the accuracy of MRI with TVS for diagnosis of rectosigmoid endometriosis and reported that both of these techniques are equally effective for diagnosing endometriosis. 19 Although laparoscopy is the gold standard for the diagnosis of endometriosis, however, efficacy of laparoscopy is reduced in patients with mild or minimal disease. It is also difficult to diagnose lesions which are atypical in appearance.…”