Hypothesis / aims of study
The Vaginal Biomechanics Analyzer (VBA) is a US patented device (USPTO 9,730,629 B2) to measure vaginal wall laxity. The vaginal probe, held by a tripod to avoid operator-dependence, permits repeated measurements (at the tip of the device through a 10 mm diameter aperture) which are brief, thus not causing any discomfort. The first-generation probe is currently used in a randomized trial on vaginal laser rejuvenation (ClinicalTrials.gov Identifier: NCT03316950). We report on the second-generation VBA incorporating an internal lighting and camera recording system, as well as two new deflection programs.
Study design, materials and methods
Following IRB approval, the second-generation VBA was tested on consecutive patients scheduled for prolapse or non-prolapse repair procedures in the operating room. Under anesthesia and before starting the procedure, patients were placed in low lithotomy position and had their bladder drained. The finger-size probe (fig 1 A) was introduced in the vagina and adjusted in depth (5 cm marking) and level for consistency. A standard program was used with an uplift of half second to 150 mmHg, with concurrent visualization and recording of the vaginal wall deflection by an attached camera connected to a small light fiber inside the probe (fig 1 B). Laxity was read on the screen in real time, and secondary curve analysis was performed to compare tracing consistency (triplicates). Two new innovative programs were developed and also tested, having advanced ramp profiles permitting selective vacuum control for uplift and downlift measurements and all done in triplicate as well.
Interpretation of results
This second-generation VBA probe performed well, adding access to the visual deformation of the vaginal wall inside the aperture of the probe during the deflection measurement. The measurement is quick, not painful, reliable because the probe is held by a tripod and not a human hand, and the size of the probe fits like a finger, thus allowing measurements in all patients. The maximum amplitude of the deflection observed represents vaginal laxity, a quantitative measurement which can be studied across patients and before and after interventions like physical therapy, hormone replacement therapy, laser rejuvenation, or surgery.