Exploring biomechanical methods to study the human vaginal wall

Aims: To critically review studies of the biomechanical properties of connective tissue in the normal and prolapsed human vaginal wall and to identify criteria that are suitable for in vivo measurements which could improve patient management. Methods: This review covers past and current ex vivo and in vivo instrumentation and analytical methods related to the elastic and viscoelastic properties of vaginal wall connective tissues. Results: Classical methods, including digital evaluation of the vagina, histological and biomechanical studies of fresh and frozen-thawed extracts, and biomechanical cadaveric tissue studies have important limitations and have yielded inconsistent results. Newer biomechanical methods may resolve these inconsistencies. One of the more promising is transient, vacuum-induced tissue expansion and relaxation, via cutometer-like devices. The technique permits noninvasive observation, applicable to longitudinal studies of patients. In vivo and ex vivo biomechanical methods may better match vaginal wall tissue properties to help with the design of surgical mesh materials, thus improving surgical support and healing. Conclusion: Methods have been identified to characterize the in vivo biomechanical behavior of the prolapsing vagina which may serve to advance the care of affected women.