Finite element analysis-based evaluation of different pessaries for female cystocele intervention

Based on finite element analysis (FEA), this study compared the effects of vaginal pessaries of different shapes and sizes on pelvic floor biomechanics in a patient with cystocele, providing a theoretical basis for clinical selection of pessaries. Pelvic floor finite element models were constructed using the patient's magnetic resonance images (MRI) data to simulate the conditions of wearing ring and Gellhorn pessaries, and the biomechanical parameters of pelvic organs were analyzed. After pessary insertion, bladder neck displacement (BND), uterine neck displacement (UND), and anterior vaginal wall (AVW) values decreased, and pelvic floor levator ani muscle (LAM), cardinal ligament (CL), and uterosacral ligament (USL) stresses were reduced, along with lower contact pressures. Bladder pressure and intravesical fluid flow velocity became more stable. The Gellhorn pessary outperformed the ring pessary in limiting displacement and reducing ligament stress, but it was prone to creating localized high-pressure zones; the ring pessary exhibited lower tissue contact pressure and a more stable urinary flow environment. A size that is too small may result in insufficient support, while a size that is too large may increase the risk of mucosal injury. The biomechanical mechanisms of the two vaginal pessaries differ; clinical selection requires comprehensive consideration of the degree of prolapse, tissue tolerance, and urodynamic characteristics. The finite element model provides an effective evaluation framework for moving beyond empirical selection of vaginal pessaries and achieving individualized fitting.