Purpose: Controversy exists regarding the role preoperative urodynamic study for asymptomatic closed spinal dysraphism 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 3 phases: (1) till postoperative 6 months, (2) till the completion of toilet training, and (3) 2 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 patients (70.7%), respectively. Spontaneous voiding was found in 125 (69.1%), 164 (90.6%), and 162 patients (89.5%) at postoperative 6 months, till the toilet training, and 2 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.
Conclusion: 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.
Keywords: Occult spinal dysraphism; Prophylactic surgery; Tethering; Toilet training; Urodynamics studies; Voiding characteristics.