Acute effect of posterior tibial nerve stimulation on neurogenic detrusor overactivity in patients with multiple sclerosis: Urodynamic study

OBJECTIVES The aim of this study was to determine the acute urodynamic effects of posterior tibial nerve stimulation (PTNS) in patients with neurogenic detrusor overactivity (NDO) caused by multiple sclerosis (MS). METHODS A total of 29 patients of whom there were 12 (41.3%) men and 17 (58.6%) women with NDO, mean age 46.5 +/- 8.5 years (range 29 to 55 years) enrolled in the study. Mean duration of MS was 8.80 +/- 3.6 years; duration of urinary disorder was 4.3 +/- 1.8 years. The expanded disability status scale (EDSS) of the study was detected 4.8 +/- 1.9. Urodynamic studies before and during PTNS were performed. Electrical stimulation was applied unilaterally from the medial malleolus and posterior to the edge of the tibia by using charge-compensated 200 microsecond pulses with a pulse rate of 20 Hz. Mean first involuntary detrusor contractions and mean maximum cystometric capacity before and during PTNS were compared. RESULTS Mean first involuntary detrusor contraction on standard cystometry was 138.34 +/- 6.36 mL (60 to 225 mL), whereas it was 230.48 +/- 8.89 mL (145 to 375 mL) during PTNS. Mean maximum cystometric capacity on standard cystometry was 193.93 +/- 9.90 mL (110 to 304 mL), whereas it was 286.48 +/- 9.09 mL (221 to 376 mL) during stimulation. The improvements in the first involuntary detrusor contraction and maximum cystometric capacity were statistically significant during stimulation (P < 0.001). The difference of mean first involuntary detrusor contraction Volume and mean maximum cystometric capacity at baseline and after PTNS was statistically significant (P < 0.001). CONCLUSIONS These results have demonstrated the objective effect of acute PTNS on urodynamic parameters. PTNS is effective to suppress detrusor overactivity in MS patients.