Dynamic magnetic resonance imaging of the pelvic floor: Technical aspects

Abstract

Dynamic magnetic resonance imaging (MRI) of the pelvic floor plays akey role in imaging complex pelvic floor dysfunction. High-quality examination is crucial for diagnostic benefit but can be technically challenging. The most important technical aspects (patient selection, patient preparation, MRI technology, MRI scan protocol, success control) for obtaining astate-of-the-art dynamic MRI of the pelvic floor are summarized. Review of the scientific literature on dynamic pelvic MR imaging with special consideration of the joint recommendations provided by the expert panels of European Society of Urogenital Radiology/European Society of Gastrointestinal and Abdominal Radiology (ESUR/ESGAR) in 2016 and Society of Abdominal Radiology (SAR) in 2019. Examination with at least 1.5 T and asurface coil after rectal instillation of ultrasound gel is clinical standard. Dynamic MRI in aclosed magnet with the patient in supine position is the most widespread technique. No clinically significant pathologies of the pelvic floor are missed compared to the sitting position in an open magnet. The minimum scan protocol should encompass static, high-resolution T2-imaging (i.e., T2-TSE) in three planes and dynamic sequences with high temporal resolution in sagittal (and possibly axial) plane (i.e., steady-state or balanced steady-state free precession) during squeezing, straining and evacuation. Detailed patient instruction and practicing prior to the scan improve patients' compliance and hence diagnostic quality. Atechnically flawless dynamic MRI of the pelvic floor according to these standards can provide information missed by other imaging modalities and hence alter therapeutic strategies.