Reliability of low-field upright MRI-based assessment of the polypropylene mesh after sacrocolporectopexy

BACKGROUND: Multicompartment pelvic organ prolapse (POP) has a negative impact on the patient's quality of life. Abdominal mesh surgery, e.g., sacrocolporectopexy (SCRP), is favored to treat complex multicompartment POP. SCRP is known for its anatomical improvement, while functional improvement is only 70% for defecatory problems. To improve our understanding of the mesh's function, a reliable assessment in a clinically relevant position is important. The aim of this study therefore is to test the reliability of a standardized analysis method on mesh trajectory and position. METHOD: A total of 25 patients treated with SCRP were included. Images were acquired with a 0.25T tiltable magnetic resonance (MR) system (G-Scan Brio, Esaote, Genoa, Italy). The mesh was annotated using three-dimensional (3D) slicer software. Annotations were performed by two observers, with different experience levels, blinded to the results of the other observer. Reliability was tested by means of the intraclass correlation coefficient (ICC) and the mean Euclidean distance (MED), with clinical relevance set at a MED difference of 10 mm. RESULTS: There was excellent agreement between the two observers for all mesh points (ICC = 0.97) and the lowest agreement for the anterior mesh points (ICC = 0.86) and the lowest points of the anterior mesh (ICC = 0.76). No clinically relevant difference in MED was found for all mesh points (9 mm), the mesh points above the connection point (8 mm), and the posterior mesh points (9 mm). CONCLUSIONS: Upright mesh assessment is feasible and reliable on 0.25T magnetic resonance (MR) images, allowing for future mesh analysis. TRIAL REGISTRATION: NL79717.091.21, 03-01-2022.