Effects of ejaculation by penile vibratory stimulation on bladder capacity in men with spinal cord lesions

Purpose: We examined the effects of ejaculation by penile vibratory stimulation on bladder capacity in men with spinal cord lesions. Material and Methods: Included in our study were 14 men with spinal cord lesions from C4 to T7 with detrusor hyperreflexia. Cystometry was performed before and immediately after ejaculation by penile vibratory stimulation to establish baseline conditions and repeated after I month of ejaculation by penile vibratory stimulation every third day. The third cystometry study was done after 1 month of ejaculation by penile vibratory stimulation every third day at home to determine any long-term effects of treatment. This third cystometry was performed 72 hours after the last ejaculation to exclude any acute effects of ejaculation by penile vibratory stimulation on detrusor hyperreflexia. In addition, 1 to 3 days later ejaculation was induced by penile vibratory stimulation and immediately followed by cystometry to examine whether it was possible to achieve an acute effect as well as a potential long-term effect. Results: Baseline urodynamic investigations revealed bladder hyperreflexia and external sphincter dyssynergia in all individuals. There was no statistically significant difference in bladder capacity at leak point before and immediately after ejaculation by penile vibratory stimulation. However, after 4 weeks of frequent penile vibratory stimulation treatment bladder capacity at leak point increased significantly from a median of 190 ml. (range 17 to 700) at baseline to 293 (range 30 to 700) (Wilcoxon signed rank test p = 0.03). Furthermore, there was a trend toward decreased intravesical pressure during the filling phase. Conclusions: Ejaculation by penile vibratory stimulation was associated with a significant increase in bladder capacity at leak point after 4 weeks of frequent treatment. This finding may have implications in the management of incontinence in men with spinal cord lesions.