Effectiveness and safety of sacral neuromodulation on neurogenic bladder and bowel dysfunction in patients with spina bifida

Abstract

To evaluate the effectiveness and safety of sacral neuromodulation (SNM) in the treatment of neurogenic bladder and bowel dysfunction in patients with spina bifida. The clinical data of 33 patients with neurogenic bladder and bowel dysfunction caused by spina bifida treated with SNM between July 2012 and May 2021 were retrospectively analyzed. There were 19 males and 14 females, with an average age of 26.0 years (range, 18.5-36.5 years). The disease duration ranged from 12 to 456 months, with an average of 195.8 months. The types of spina bifida included 8 cases of occult spina bifida and 25 cases of meningocele/myelomeningocele. Clinical symptoms included 19 cases of urgency-frequent urination, 18 cases of urinary incontinence, 27 cases of chronic urinary retention, and 29 cases of bowel dysfunction. Image urodynamics showed that 4 patients had detrusor overactivity (DO) and 29 patients had detrusor underactivity (DU). Vesicoureteral reflux (VUR) was found in 5 ureters (4 patients). SNM procedure was divided into experiential treatment and permanent implantation. Patients who were evaluated as successful or willing to be permanently implanted after experiential treatment would implant the permanent pulse generator. The duration of experiential treatment was 14-28 days, with an average of 19.2 days; there was no complication during this period, and the overall success rate was 69.69% (23/33). At the end of experiential treatment, the urination frequency in 24 hours, urine volume per time, urinary urgency score, and urine leakage of patients were significantly improved when compared with those before experiential treatment ( P<0.05); there was no significant difference in postvoid residual volume between before and after experiential treatment ( t=1.383, P=0.179). The success rate of patients with chronic urinary retention after experiential treatment (25.93%) was significantly lower than that of urgency-frequent urination (63.16%) and urinary incontinence (61.11%) ( χ 2=7.260, P=0.064). Compared with those before experiential treatment, the maximum cystometric capacity and compliance increased and the maximum detrusor pressure during filling decreased significantly ( P<0.05). Among the 4 patients with DO before experiential treatment, DO disappeared in 2 cases; 27 patients with DU before experiential treatment did not recover the normal contraction of detrusor during micturition. Among the 5 ureters with VUR before experiential treatment, 2 VUR disappeared at the end of experiential treatment, and the VUR grade or the bladder volume before VUR of the other 3 ureters were improved. At the end of experiential treatment, the neurogenic bowel dysfunction (NBD) score and the grade of bowel dysfunction significantly improved ( P<0.05). A total of 19 patients received permanent implantation, of which 11 patients needed to empty the bladder in combination with intermittent catheterization. SNM is effective for neurogenic bladder and bowel dysfunction in patients with spina bifida. At the same time, it can significantly improve the urodynamic parameters during urine storage and avoid upper urinary tract damage.