Assessment of the Effectiveness of the Vaginal Contrast Media in Magnetic Resonance Imaging for Detection of Pelvic Pathologies: A Meta-analysis

Objective Magnetic resonance imaging (MRI) is an excellent modality for pelvic imaging. The anatomy of uterine cavity and vagina is optimally evaluated when the walls, which may spontaneously be collapsed, are distended. Distension of these cavities during pelvic MRI for evaluation of gynecologic diseases has been conducted with vagina, filled with ultrasound gel or saline solution. In this meta-analysis, we aim to assess the effectiveness of vaginal contrast media in MRI for improving the detection of pelvic pathologies. Methods The PubMed, MEDLINE, EMBASE, Web of Science, Google Scholar, Science Citation Index, and Cochrane Library databases were systematically searched through March 2019 for studies of the accuracy of MRI using vaginal contrast media in the diagnosis and staging of pelvic pathologies. Four eligible studies of a total of 120 patients were included in the meta-analysis. The sensitivity rates and relative risk for MRI, before and after vaginal contrast medium administration, were pooled, and their 95% confidence intervals (CIs) were determined. Results The pooled sensitivity rate for MRI before administering intravaginal contrast medium in detecting pelvic pathologies was 63% (95% CI, 54%-72%), and that after was 89% (95% CI, 83%-93%). The interstudy heterogeneity rate (assessed using the I2 statistic) was relatively low: 13% (P = 0.33) and 0% (P = 0.45) before and after vaginal contrast medium use, respectively. The average relative risk was 1.54 (SD, 0.22; 95% CI, 1.18-1.89; median, 1.50; range, 1.34-1.80). This demonstrated that, on average, the sensitivity rate for MRI in detecting pelvic disorders increased by 54% after the use of a vaginal contrast medium. Conclusions Use of vaginal contrast media improved the diagnostic ability of MRI in identifying pelvic pathologies.