LASER PROBE WITH INTEGRATED CONTACT COOLING FOR SUBSURFACE TISSUE THERMAL REMODELING.

Abstract

Over 6.5 million women in the United States suffer from female stress urinary incontinence (SUI). Only ~200,000 women choose surgery. There may be a role for a non-surgical, minimally invasive procedure that provides thermal shrinkage/remodeling of submucosal collagen in the endopelvic fascia. This study describes design, characterization, and preliminary testing of a novel probe with integrated contact cooling for potential use in transvaginal laser treatment of SUI. Laser energy at a deeply penetrating, near-infrared wavelength of 1075 nm was delivered through a 600-μm-core fiber optic patchcord into a 90° side-firing probe head (19 × 22 mm) with integrated flow cell and sapphire window cooled to -2°C by circulating an alcohol-based solution. An inflatable balloon attached to the probe insured contact with vaginal wall. A force sensor and thermocouples monitored pressure and temperature. Thermal lesions were created in vaginal tissue of three cadavers (power = 4.6-6.4 W; spot diameter = 5.2 mm; time = 30 s). Thermal lesion areas measured 3.1-4.6 mm², while preserving the vaginal wall to a depth of 0.8-1.1 mm. Consistent tissue contact and cooling was maintained using the force sensors. Preliminary cadaver studies demonstrated subsurface treatment of endopelvic fascia with partial preservation of the vaginal wall. Future studies will optimize parameters for thermal remodeling with further tissue surface preservation.