Model-directed Design of Vaginal Stents to Prevent Post-radiation Stenosis

MODEL-DIRECTED DESIGN OF VAGINAL STENTS TO PREVENT POST-RADIATION STENOSIS Debilitating vaginal stenosis is an under-recognized, poorly understood sequela that occurs in up to 75% of patients who undergo pelvic radiation treatments. Patients with vaginal stenosis suffer from pain, inability to pass menstrual contents, difficulty with pelvic exams, inability to have intercourse, and may require corrective surgery. There is a critical need for a patient-forward vaginal stent that can apply constant pressure to maintain vaginal caliber post-radiation treatment. Our proposed design for a self-fitting vaginal stent utilizes a shape-memory polymer (SMP) foam that can assume a secondary, compressed shape for ease of deployment. Upon insertion, the change in temperature and hydration initiates foam expansion to shape fit to the individual patient and restore the lumen of the stent to allow egress of vaginal secretions. Our exciting prior work on the development of aSMP stent by this team demonstrated deployment with self-fitting shape recoveryand retention in both benchtop and pilot rabbit studies. In the proposed studies, we will add an antifouling coating to prevent bacterial attachment and a new geometry for ease of removal. Computational models that capture the complex geometry, material behavior, and boundary conditions will be developed to provide an in silico testing framework to accelerate design of gynecological devices. Upon completion, we will have developed aself-fittingvaginal stent that addresses current egress failures, developed new computational vaginal models and benchtop testing for gynecological device development, and elucidated key mechanisms in preventing/reversing post-radiation stenosis. The synergistic team undertaking the proposed studies has the requisite experience in clinical practice (Hakim), polymer engineering (Cosgriff-Hernandez), shape-memory polymer chemistry (Grunlan), and computational modeling (Rausch) to complete these studies. Although our immediate goal is to address the urgent clinical need of post-radiation patients, a self-fitting vaginal stent would have direct extension as a therapeutic modality for post-surgical vaginal stenosis.