UC San Diego

Cervical cancer is a common malignancy worldwide and is one of the leading causes of death for women. Vaginal stenosis is a common long-term side effect of pelvic radiation. Vaginal dilator therapy is the most common and universally accepted strategy to prevent vaginal stenosis, as it can promote epithelialization and increased vascularity of the tissues after brachytherapy. However, many patients feel uncomfortable with using commercial vaginal dilators that are manufactured using hard latex materials, struggle with transitioning from one dilator size to another, and have difficulty dilating the apex of the vaginal canal. In this thesis, an inflatable vaginal dilator made from silicone polymers was developed to overcome the problems inherent with hard plastic dilators. Silicone polymers are soft and inflatable materials and ideally suited for this application. In this thesis, we have investigated the stress-strain characteristics of silicone material used for manufacturing vaginal dilators. We have determined a two-term Mooney-Rivlin equation to describe the behavior of silicone. Finite element analysis was used to simulate the dilator inflation and determine the force that the dilator exerts on the vaginal wall. In addition, experimental studies were conducted to verify the finite element simulation. Silicone dilator balloons of various wall thicknesses were fabricated.