Development of a cost-effective bladder-prostate phantom model to simulate the effects of minimally invasive surgical treatments (MIST) for benign prostatic hyperplasia (BPH) and its validation by pressure-flow study

Development of a cost-effective Bladder-Prostate Phantom model to simulate the effects of minimally invasive surgical treatments (MIST) for benign prostatic hyperplasia (BPH) and its validation by pressure-flow studyAbstractWe developed and bench-tested an economical bladder-prostate training construct to simulate bladder outlet obstruction and its relief during non-thermal minimally invasive interventions. The aim was to create a simple, locally fabricable platform to practise urethral implantation and quantify its urodynamic effects. The system combined a paediatric silicone AmbuBag (≈500 mL, wall thickness 3.6 mm, Shore 78 Sh0) as a compressible reservoir, a funnel-shaped neck, a collapsible silicone urethral tube (internal diameter 10 mm, wall thickness 0.95 mm, Shore 65 Sh0), and polyurethane foam balls (Shore 25 Sh00) to represent prostatic lobes compressing a 5-cm urethral segment. Using a multichannel urodynamic device, we recorded pressure-flow parameters in three configurations: obstruction alone, obstruction with an intraurethral coil-spring implant, and obstruction with a traction implant. Under obstruction, an infusion rate of 75 mL/min yielded a voided volume of 351 mL, an end-fill pressure of 8 cm H₂O, an opening detrusor pressure of 35 cm H₂O, a peak flow (Qmax) of 7.6 mL/s, a PdetQmax (detrusor pressure at peak flow) of 102 cm H₂O, and a bladder outlet obstruction index (BOOI) of 87.0, consistent with severe outflow resistance. With the coil-spring implant, peak flow increased to 31.8 mL/s, with PdetQmax reduced to 11 cm H₂O and the maximum detrusor pressure to 78 cm H₂O. With the traction implant, peak flow increased again to 36.7 mL/s, with an opening pressure of 84 cm H₂O, a PdetQmax of 14 cm H₂O, and a maximum detrusor pressure of 109 cm H₂O. These changes demonstrate improved pressure-flow performance, supporting this construct as a practical platform for device testing and skills training.