Computer simulations of thermal tissue remodeling during transvaginal and transurethral laser treatment of female stress urinary incontinence.

BACKGROUND AND OBJECTIVES: A non-surgical method is being developed for treating female stress urinary incontinence by laser thermal remodeling of subsurface tissues with applied surface tissue cooling. Computer simulations of light transport, heat transfer, and thermal damage in tissue were performed, comparing transvaginal and transurethral approaches. STUDY DESIGN/MATERIALS AND METHODS: Monte Carlo (MC) simulations provided spatial distributions of absorbed photons in the tissue layers (vaginal wall, endopelvic fascia, and urethral wall). Optical properties (n,µa ,µs ,g) were assigned to each tissue at λ = 1064 nm. A 5-mm-diameter laser beam and incident power of 5 W for 15 seconds was used, based on previous experiments. MC output was converted into absorbed energy, serving as input for finite element heat transfer simulations of tissue temperatures over time. Convective heat transfer was simulated with contact probe cooling temperature set at 0°C. Variables used for thermal simulations (κ,c,ρ) were assigned to each tissue layer. MATLAB code was used for Arrhenius integral thermal damage calculations. A temperature matrix was constructed from ANSYS output, and finite sum was incorporated to approximate Arrhenius integral calculations. Tissue damage properties (Ea ,A) were used to compute Arrhenius sums. RESULTS: For the transvaginal approach, 37% of energy was absorbed in the endopelvic fascia target layer with 0.8% deposited beyond it. Peak temperature was 71°C, the treatment zone was 0.8-mm-diameter, and 2.4 mm of the 2.7-mm-thick vaginal wall was preserved. For transurethral approach, 18% energy was absorbed in endopelvic fascia with 0.3% deposited beyond the layer. Peak temperature was 80°C, treatment zone was 2.0-mm-diameter, and 0.6 mm of 2.4-mm-thick urethral wall was preserved. CONCLUSIONS: Computer simulations suggest that transvaginal approach is more feasible than transurethral approach. Lasers Surg. Med. 49:198-205, 2017. © 2016 Wiley Periodicals, Inc.

Internet Use Among Urogynecology Patients in North Carolina.

OBJECTIVES: Given limited information regarding digital technology use among patients, we sought to evaluate Internet use among younger (<65 years) as compared to older (≥65 years) women and to assess factors associated with Internet use. METHODS: We administered an anonymous questionnaire on digital technology use to English-speaking women who presented to our Urogynecology practice during a 1-month period. The questionnaire assessed the following sociodemographics: age, race, education, income, and insurance status. For our primary outcome, we assessed Internet use among younger versus older women. We also conducted a logistic regression analysis to evaluate the association of age with Internet use, while adjusting for potential confounders. RESULTS: A total of 556 women presented during the study period. Among these women, 506 completed the survey, for a 91% response rate. There were 282 (55.7%) younger women and 222 (43.9%) older women. Most of the younger and older cohorts were white (77% vs 86.5%, P = 0.02). Younger women were more educated (79.8% vs 59.5% ≥ college education; P < 0.0001) and had a higher income (58.3% vs 39.8% ≥ $50,000; P < 0.0001). For our primary outcome, younger women were significantly more likely to use the Internet (93.8% vs 66.3%, P < 0.001). In a logistic regression model which adjusted for age, race, education, and income, younger women remained significantly more likely to use the Internet (odds ratio, 6.6; 95% CI, 3.4-13.0). CONCLUSIONS: Although women younger than 65 years reported greater Internet use when compared to women 65 years or older, most of older women also used the Internet.