Sacral nerve neuromodulation in the treatment of patients with refractory motor urge incontinence: Longterm results of a prospective longitudinal study

Purpose: Conservative treatment rarely results in a durable cure of patient s with urge incontinence and bladder overactivity. Instrumental and surgica l procedures often have significant side effects and less than optimal resu lts. We developed a technique of sacral nerve neuromodulation using chronic unilateral electrical stimulation of the S3 sacral nerve to inhibit the mi cturition reflex to provide effective nondestructive alternative therapy fo r patients whose condition is refractory to conservative treatment. Materials and Methods: Of 85 patients 45 who responded to a test with a tem porary electrode underwent implantation of a permanent S3 sacral nerve elec trode coupled to a pulse generator. Treatment results were evaluated by uro dynamic studies and voiding/incontinence diaries documenting pad use, incon tinence episodes, voiding frequency and voided volume. Partial success and cure were defined as 50% to 90% and more than 90% improvement, respectively , in pad use and/or incontinence episodes. Results: Of 45 patients 18 (40%) were cured at an average followup of 47.1 months and 9 (20%) achieved partial success. Median number of pads used and median number of incontinence episodes daily had decreased from 5.4 to 1.2 (p = 0.0001) and 7.1 to 1.3 (p = 0.0001), respectively, 6 months after imp lantation. Subsequently these results remained almost constant for 5 years. Bladder overactivity disappeared in 19 of the 44 patients (43%). The repea t intervention rate was 37.7% and there was no permanent injury or nerve da mage. Conclusions: Sacral nerve neuromodulation is safe, effective and durable in patients with urge incontinence refractory to conservative treatment.