Development of Extraocular Muscle Prosthesis for Paralytic Strabismus

麻痹性斜视眼外肌假体的研制

• 批准号: 7746157
• 负责人: Yasushi Kato
• 金额: $ 16.25万
• 依托单位: INNFOCUS, LLC
• 依托单位国家: 美国
• 财政年份: 2009
• 资助国家: 美国
• 起止时间: 2009-09-30 至 2011-09-29
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/7746157
• 关键词: Acute; Adopted; Affect; Amputation; Animal Model; Animals; Back; Biocompatible; Biocompatible Materials; Bone plates; Characteristics; Coiled Springs; Complex; Complication; Coronary; Cranial nerve palsies; Data; Development; Device Designs; Devices; Diplopia; Elasticity; Elements; Engineering; Exotropia; Eye; Eye Movements; Face; Fatigue; Frequencies; Functional disorder; Generations; Goals; Implant; In Vitro; Inflammatory; Investigation; Measures; Mechanics; Methods; Modeling; Movement; Muscle; Ocular orbit; Operative Surgical Procedures; Oryctolagus cuniculus; Outcome; Paralysed; Particulate; Patients; Phase; Phase II Clinical Trials; Polymers; Positioning Attribute; Process; Property; Prosthesis; Prosthesis Design; Reaction; Relaxation; Research Project Grants; Resistance; Rotation; Safety; Shapes; Silicone Elastomers; Sinus; Site; Small Business Innovation Research Grant; Staging; Stents; Strabismus; Stress; Testing; Tissues; Titanium; Trauma; adduct; biocompatible polymer; biomaterial compatibility; commercialization; design; effective therapy; experience; improved; in vivo; isobutylene; manufacturing process; medial rectus muscle; nitinol; novel; orbit muscle; prototype; public health relevance; sample fixation; tool

DESCRIPTION (provided by applicant): The ultimate goal of this Small Business Innovation Research project is to develop the first generation extraocular muscle prosthetic device designed to correct paralytic strabismus. The focus of Phase I of this project is to refine the design of the prosthesis and to test the limits of the device and its components. A method of measuring extraocular muscle forces will be developed and tested using an animal model. Furthermore, a short-term in vivo animal study to assess the biocompatibility of the device will be performed. A common ophthalmic complication encountered with increasing frequency in functional endoscopic sinus surgery (FESS) is the inadvertent amputation of the medial rectus muscle. Extraocular muscle dysfunction can also be manifested in cranial nerve palsies or vehicular trauma to the muscles. Consequently, the involved eye will assume a large angle exotropia, and the patient will experience debilitating diplopia and will be unable to adduct or abduct the involved eye. Conventional surgical options typically result in suboptimal outcomes as the eye is permanently tethered to a fixed primary position, limiting ocular movements and forcing the patient to adopt face turns to maintain binocular fusion. These major shortcomings call for the need of an alternative remedy in the form of a mechanical prosthetic device to obviate the fixed, locked primary position of the affected eye. The unique features of this extraocular muscle prosthesis include: 1) a coiled Nitinol spring that possesses inherent stiffness to counterbalance the passive forces of the antagonist eye muscles when the eye is in the primary position but also allows linear elasticity to permit eye movement initiated by an antagonist muscle. The spring also has inherent recoil tension to restore the eye back to the primary position upon relaxation of the antagonist muscle; 2) a novel biocompatible polymer, poly(styrene-block-isobutylene-block- styrene) or "SIBS," that does not elicit significant inflammatory reaction or encapsulation when implanted and has a safety track record in coronary stent use. This biomaterial is extruded as a protective, elastic envelope that insulates the spring coil from the surrounding orbital tissues; and 3) a titanium, T-shaped bone plate that provides a firm metallic fixation point to the orbit and directs the prosthesis posteriorly from the muscle insertion site towards the apex of the orbit, coinciding with the axis of the paretic muscle that the prosthesis is designed to replace. PUBLIC HEALTH RELEVANCE: The goal of this project is to develop an extraocular muscle prosthetic device to correct complex eye muscle misalignment conditions in which effective therapy remains elusive. Conventional surgical options typically result in suboptimal outcomes as the eye is permanently tethered to a fixed position, unable to rotate. The device developed in this project is designed to permit eye rotations; the Extraocular Muscle Prosthesis is a novel prosthetic device comprised of a new polymeric biomaterial that is extremely biocompatible in the eye and has shown insignificant encapsulation compared to silicone rubber.

描述（由申请人提供）：本小型企业创新研究项目的最终目标是开发第一代眼外肌假体装置，用于矫正麻痹性斜视。该项目第一阶段的重点是完善假体的设计，并测试设备及其组件的极限。将开发一种测量眼外肌力的方法，并使用动物模型进行测试。此外，将进行短期体内动物研究以评估该装置的生物相容性。在功能性内窥镜鼻窦手术（FESS）中，一个常见的眼科并发症是无意中切除内侧直肌。眼外肌功能障碍也可表现为脑神经麻痹或车辆外伤的肌肉。因此，受累的眼睛会出现大角度的外斜视，患者会出现衰弱性复视，无法内收或外展受累的眼睛。传统的手术选择通常会导致不理想的结果，因为眼睛永久地固定在固定的初始位置，限制了眼球运动，迫使患者采用面部旋转来维持双眼融合。这些主要缺陷需要一种替代疗法，即机械假体装置，以消除受影响眼睛的固定锁定原发位置。这种眼外肌假体的独特特点包括：1)一个卷曲的镍钛诺弹簧，具有固有的刚度，以平衡当眼睛处于主要位置时拮抗眼肌的被动力，但也允许线性弹性，以允许拮抗肌发起的眼球运动。弹簧还具有内在的反冲张力，使眼睛在拮抗肌放松后恢复到最初的位置；2)一种新型的生物相容性聚合物，聚（苯乙烯-异丁烯-块-苯乙烯）或“SIBS”，在植入时不会引起明显的炎症反应或封装，并且在冠状动脉支架使用中具有安全记录。这种生物材料被挤压成一种保护性的弹性包膜，将弹簧线圈与周围的眼眶组织隔离开来；3)一个钛的t形骨板，为眼眶提供一个坚固的金属固定点，并将假体从肌肉插入部位向后指向眼眶顶点，与假体设计要替换的麻痹肌的轴线一致。公共卫生相关性：该项目的目标是开发一种眼外肌假体装置，以纠正复杂的眼肌错位情况，其中有效的治疗方法仍然难以捉摸。传统的手术选择通常会导致不理想的结果，因为眼睛永久地固定在一个固定的位置，无法旋转。在这个项目中开发的设备被设计成允许眼睛旋转；眼外肌假体是一种新型的假体装置，由一种新的聚合物生物材料组成，与硅橡胶相比，这种材料在眼睛中具有极高的生物相容性，并且具有微不足道的封装性。