Purpose: Controversy exists regarding the role preoperative urodynamic study for asymptomatic closed spinal dysaraphism as it has failed to reveal the benefit in surgical decision and expectation of urological outcomes.We explore the relationship between preoperative videourodynamic study and postoperative urological outcomes after toilet training completed, focusing on their capability of spontaneous voiding. Methods:We retrospectively reviewed the data of 181 patients who underwent preventive spinal cord untethering and followed at least till the completion of toilet training. Before untethering, patients underwent preoperative videourodynamic study. Postoperative voiding function was evaluated in three phases 1) till postoperative 6 months 2) till the completion of toilet training 3) two years after toilet training. Changing distribution of emptying pattern at each period was described. Also, relevance to preoperative urodynamic parameters on spontaneous voiding and urinary continence after toilet training was assessed. Results: Spinal lipoma and low-lying conus were found in 145 (80%) and 128 (70.7%) patients, respectively. Spontaneous voiding was found in 125 (69.1%), 164 (90.6%) and 162 (89.5%) patients at postoperative 6 months, till the toilet training and two years after toilet training, respectively. Videourodynamics helped to clarify the presence of vesicourethral synergy. This was correlated with spontaneous voiding at postoperative 6 months and better urinary continence after 2 years of toilet training. Conclusions: Eventual spontaneous voiding was achieved till toilet training in 90% patients following preventive untethering. Those showing preoperative vesicourethral synergy was associated with faster achievement of spontaneous voiding and better urinary continence when they enter elementary school.

INTRODUCTION AND OBJECTIVE: HoLEP is a an underutilized, minimally invasive approach for the management of benign prostatic hyperplasia. Its steep learning curve and lack of realistic simulation platforms with incorporated objective metrics has hindered the adoption of this technique. Our aim is to demonstrate the design and validation of a high-fidelity non-biohazardous hydrogel platform fabricated to specifications attained through expert consensus.METHODS: Validation was completed in 3 phases: Phase 1, Delphi methodology to gain consensus from an expert panel of endourologists. Consensus (>80% agreement) over 3 rounds defined 81 essential elements. Phase 2, Prototype development: these essential items were incorporated into prototypes fabricated using a combination of hydrogel molding and 3D printing. Phase 3: Validation comparing 6 experts and 6 novices performance from 4 centers using the consensus based objective and subjective metrics.RESULTS: The model contained all 9 anatomic components (ex. bladder, ureteric orifices, lateral and median lobes, capsule, urethra), 7 objective evaluation metrics (ex. injury of ureteric orifices or bladder neck, perforation of the bladder or prostate capsule), and 5 procedural steps except for hemostasis and morcellation. Categorically overall utility, anatomical and procedural components, tissue fidelity, and assessment of performance received an 82%, 78%, 73% and 82% satisfaction score by experts respectively. Laser and instrument tissue interactions achieved highest (>85%) satisfaction. Experts outperformed novices in enucleation time (15.1 vs 47.5 min p[0.001), weight of adenoma resected (75.5 vs 49 g p[0.04) and developed global evaluation too (27 vs 15.8 p[0.001). All experts agreed the model could provide a safe training alternative, be used to evaluate trainee performance, and trial new approaches in a risk-free environment.CONCLUSIONS: This is the first consensus-based approach to design and provide initial validation of a non-biohazardous HoLEP simulation with incorporated evaluation metrics capable of supplementing HoLEP training. Further validation studies are required to establish its effectiveness as a training platform.