Resorbable, Shape Memory Stents to Prevent Vaginal Fibrosis

可吸收形状记忆支架预防阴道纤维化 每年有近5万名女性青少年患者接受阴道重建， 这些患者中有73%在手术后会出现阴道纤维化。儿科和青少年 妇科外科医生经常在术后立即使用阴道支架以促进伤口愈合。 不幸的是，市场上唯一可用的阴道支架是大的、不符合人体工程学的设计， 在儿科人群中耐受。事实上，这些支架直到最近才重新上市， 停产5年以上。因此，许多外科医生不得不求助于临时设备 在手术室里创造的。所有这些选项都带来了部署挑战、有限的规模调整选项， 固位不良，经常需要撑开阴道以防止流出。迫切需要一个 具有适当尺寸的新型儿科/阴道专用阴道支架，可对 新阴道的边界，以防止纤维化，并在伤口愈合期间保持阴道口径。关键 设计特点将包括易于插入，改善人体工程学，防止出口与瓦尔萨尔瓦， 最终预防纤维化和改善阴道愈合。此外，开发新的可吸收 阴道支架将提供额外的优势，因为在术后不需要取出支架， 磨损时间已完成。在可吸收阴道支架的设计中，需要平衡机械性能， 使得支架保持阴道开放的特性（例如，足够的径向强度），同时避免不利的 生物反应，如组织过度生长，并确保足够的灵活性，病人的舒适度。我们 目的是设计一种可吸收的形状记忆阴道支架，以提高临床疗效和质量 阴道手术后的儿童和青少年患者的生命周期。我们提出的设计采用了一种形状- 记忆泡沫是可生物降解的，并且可以呈现第二压缩形状以便于部署。 在插入时，温度和水合作用的变化将引发泡沫的膨胀，以形状适合于泡沫。 单个患者，并恢复支架的管腔以允许阴道分泌物流出。独特的是，这 避免了需要外部球囊来膨胀支架，这是当前设计的常见策略， 在临床部署期间造成挑战。除了可调的聚合物化学，多孔 结构允许多种方法来优化机械性能、形状恢复和再吸收 动力学在本研究中，我们将制作并测试这种新型阴道支架的部署和保留 在台式模型中进行设计，然后在兔子模型中进行评估。儿科阴道支架早该出现了 这项研究在设计上是独一无二的，以满足这一服务不足人群的需求。这种多功能设计可以 也可为妇科和结直肠癌放疗后阴道狭窄的成人患者量身定制 治疗

RESORBABLE, SHAPE MEMORY STENTS TO PREVENT VAGINAL FIBROSIS Nearly 50,000 female adolescent patients undergo vaginal reconstruction each year, and approximately 73% of these patients will suffer from debilitating vaginal fibrosis following surgery. Pediatric and adolescent gynecologic surgeons often use vaginal stents in the immediate postoperative setting to facilitate wound healing. Unfortunately, the only available vaginal stents on the market are large, non-ergonomic designs that are poorly tolerated in the pediatric population. Indeed, these stents only recently became available again after being removed from production for more than 5 years. As a result, many surgeons have resorted to make-shift devices created in the operating room. All of these options present deployment challenges, limited sizing options, and poor retention, which frequently requires suturing of the vagina to prevent egress. There is a critical need for a new pediatric/adolescent-specific vaginal stent with appropriate sizing that can apply constant pressure to the boundaries of the neovagina to prevent fibrosis and maintain vaginal caliber during wound healing. Key design features will include easy insertion with improved ergonomics, prevention of egress with Valsalva, and ultimately prevention of fibrosis and improved vaginal healing. In addition, the development of new resorbable vaginal stents would offer additional advantages by eliminating the need for postoperative stent removal after wear-time is complete. In the design of a resorbable vaginal stent, it is necessary to balance mechanical properties such that the stent maintains vaginal patency (e.g., sufficient radial strength) while avoiding adverse biological responses, such as tissue overgrowth, and ensuring sufficient flexibility for patient comfort. Our objective is to design a resorbable, shape-memory vaginal stent that can improve clinical outcomes and quality of life for pediatric and adolescent patients following vaginal surgery. Our proposed design utilizes a shape- memory foam that is biodegradable and can assume a secondary, compressed shape for ease of deployment. Upon insertion, the change in temperature and hydration will initiate the expansion of the foam to shape fit to the individual patient and restore the lumen of the stent to allow egress of vaginal secretions. Uniquely, this circumvents the need for an external balloon to inflate the stent, a strategy common to current designs that causes challenges during clinical deployment. In addition to the tunable polymer chemistry, the porous architecture allows for multiple methods to optimize the mechanical properties, shape recovery, and resorption kinetics. In the proposed studies, we will fabricate and test the deployment and retention of this newvaginal stent design in a benchtop model followed by assessment in a rabbit model. A pediatric vaginal stent is long overdue and this study is unique in its design to meet the needs of this underserved population. This versatile design can also be tailored for adult patients with post radiation vaginal stenosis due to gynecologic and colorectal cancer treatment.