Dynamic magnetic resonance imaging of the female pelvic floor—a pictorial review

Pelvic floor dysfunctions represent a range of functional disorders that frequently occur in adult women, carrying a significant burden on the quality of life, and its incidence tends to increase attending to the expected aging of the population. Pelvic floor dysfunctions can manifest as incontinence, constipation, and prolapsed pelvic organs. Since pelvic floor weakness is frequently generalized and clinically underdiagnosed, imaging evaluation is of major importance, especially prior to surgical correction. Given some interobserver variability of soft-tissue measurements, MR defecography allows a noninvasive, radiation-free, multiplanar dynamic evaluation of the three pelvic compartments simultaneously and with high spatial and temporal resolution. Both static/anatomic and dynamic/functional findings are important, since pelvic disorders can manifest as whole pelvic floor weakness/dysfunction or as an isolated or single compartment disorder. Imaging has a preponderant role in accessing pelvic floor disorders, and dynamic MR defecography presents as a reliable option, being able to evaluate the entire pelvic floor for optimal patient management before surgery. The purpose of this article is to address the female pelvic anatomy and explain the appropriate MR Defecography protocol, along with all the anatomic points, lines, angles, and measurements needed for a correct interpretation, to later focus on the different disorders of the female pelvic floor, illustrated with MR defecography images, highlighting the role of this technique in accessing these pathologic conditions.