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Updated: May 19, 2026

Nerve-sparing Mid-urethral Obstruction (NeMO) in Female Small Rodents
Published on: April 25, 2017
Urethral sphincter innervation and clitoral blood flow after the transobturator (TOT) approach
M G Matarazzo1, S Cianci, L Rampello
1Department of Medical-Surgical Specialties, University of Catania, Catania, Italy.
Introduction And Hypothesis:
The aim of the study was to exclude neurovascular damage due to prosthetic mini-invasive surgery using transobturator tape (TOT) by pre- and postoperative electromyography (EMG) of the striated urethral sphincter and a color Doppler ultrasonography evaluation of clitoral blood flow.
Methods:
A total of 25 women affected by clinical stress urinary incontinence (SUI) were enrolled. After undergoing urodynamic assessment, pelvic organ prolapse quantification, urine culture, Q-tip test, and stress test, each subject underwent color Doppler ultrasonography to record clitoral blood flow and EMG of the urethral sphincter with a needle electrode inserted through the mucosa into the muscle tissue before surgery. A single urogynecologist performed the TOT surgical technique for the treatment of all patients. Urogynecologic examination, EMG, and color Doppler ultrasound follow-up were performed at 1 and 6 months after surgery.
Results:
At the urogynecologic examination performed 1 and 6 months after the TOT approach the stress test was negative, urethral hypermobility was reduced, and sling exposure was not observed for each patient. There was no statistically significant difference in electromyographic values (p > 0.05) in both the follow-ups with regard to baseline values. Pulsatility index (PI), resistance index (RI), and peak systolic velocity (PSV) values increased during the first follow-up (p < 0.01); PI and RI values increased during the second follow-up with respect to baseline values (p < 0.01)
Conclusions:
TOT prosthesis surgery, avoiding denervation and devascularization of pelvic structures, does not damage the urethral sphincter.
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