2 upon the concomitant presence of vesical neck funneling [13]. Ultrasound conﬁrmation of funneling in 111 patients, as reported by Huang and Yang, was associated with a lower maximal urethral closure pressure (MUCP), a smaller area under the urethral pressure proﬁle curve, a lower Valsalva leak point pressure (VLPP), and a larger volume of leakage on pad test [14]. 3. Transurethral Radiofrequency Mechanism of Action Transurethral RF treatment of the bladder neck and proximal urethra is thought to reduce funneling through the denatu- ration of submucosal collagen, with a resultant reduction in tissue compliance. Similar technology has proven eﬀective in the treatment of patients with gastroesophageal reﬂux disease and fecal incontinence [15, 16]. In a preclinical porcine study employing transurethral RF, Valsalva leak point pressure was higher in the treatment group receiving 24 foci of RF energy at 65◦C as compared to controls at 8 weeks (P = 0.06) [17]. 4. Safety of Transurethral Radiofrequency Transurethral RF collagen denaturation diﬀers from RF ablation in that subnecrotic temperatures are employed, resulting in collagen remodeling as opposed to necrosis [17]. Additionally, treated foci are microscopic, avoiding gross tissue destruction. In the aforementioned animal study by Edelstein, none of the 30 treated animals demonstrated obstruction or stricture within the proximal urethra or bladder neck. Histopathology after sacriﬁce revealed, most commonly, focal chronic inﬂammation within the sub- mucosa 1-2 mm beneath the epithelium, with evidence of ﬁbroplasia and vascular proliferation [17] (Figure 1). Created are localized regions of denatured collagen at each focus, approximately 200 µ in diameter [23]. 5. The Renessa Device Renessa is an FDA-approved device which includes an RF generator, a sterile single-use 21 F transurethral probe, foot pedal, probe interface cable, and standard AC power cord (Figure 2). Low-power RF energy is delivered through four partially insulated 23-gauge nickel-titanium needle electrodes deployed from the probe shaft into the submucosa of the bladder neck and proximal urethra (Figure 3). Tissue temperatures are measured automatically. Impedance is also reported prior to energy delivery to ensure appropriate contact between electrodes and tissue. Irrigation of the mucosa with sterile water occurs transurethrally throughout the duration of the procedure to prevent overheating of the mucosa and submucosa. Energy is delivered to a total of thirty-six sites circumferentially. 6. Procedure Description The radiofrequency probe is inserted until the tip is within the bladder lumen. The balloon is then insuﬄated with Obstetrics and Gynecology International 2 months (porcine) Figure 1: Porcine bladder neck posttreatment with Renessa. histo- logic image (hematoxylin and eosin) of porcine bladder outlet at 8 weeks following radiofrequency collagen remodeling. Denatured collagen is surrounded by focal chronic inﬂammatory cells. Figure 2: Renessa equipment. 10 cc of water. To treat the bladder neck, the electrodes are deployed ﬁrst, and gentle traction along the previ- ously determined urethral axis is applied (approximately 1/2 pound of force with the operator’s index and middle ﬁngers). The screen will display impedance upon initial pedal pressure. If all electrodes read less than 300 ohms, the pedal is pressed again to begin radiofrequency delivery. During treatment, the four electrodes traverse the mucosa