Visibility of pelvic organ support system structures in magnetic resonance images without an endovaginal coil

Objective: The aim of this study was to determine which elements of the pelvic organ support system are visible on magnetic resonance imaging performed without an endovaginal coil. Study Design: Proton density–weighted pelvic magnetic resonance images were obtained for 20 healthy continent nulliparous women with a mean (±SD) age of 30.1 ± 5.1 years (range, 22-42 years). Standardized analyses of transverse, coronal, and sagittal key images were carried out to describe pelvic organ support system anatomy. Results: Details of both the muscular and fascial supports were clearly seen. The endopelvic fascia was visible on transverse images and could be seen to laterally attach the proximal vagina to the pelvic wall. Its appearance was consistent with its composition of a network of connective tissue, vessels, and nerves. The upward, lateral, and dorsal direction of its most cephalic suspending fibers was visible on both transverse and coronal images. The different nature of the uterosacral ligament relative to the cardinal ligaments was also demonstrated in transverse images. The endopelvic fascia’s attachment to the pelvic walls was visible in the midvagina. The 3 parts of the levator ani muscle were likewise visible—the pubococcygeus, puborectalis, and iliococcygeus. Fusion of the levator ani muscle and the vagina at the level of the middle urethra could be recognized on transverse and coronal images. Conclusion: Magnetic resonance imaging depicted structures of the pelvic organ supports, including the endopelvic fascia and pelvic floor muscles, without the need for an endovaginal coil. (Am J Obstet Gynecol 2001;184:1156-63.)