Ahmed Iqbal Ike K, Sadruddin Omar, Panarelli Joseph F
John Moran Eye Center, University of Utah, Salt Lake City, UT, USA.
University of Toronto, Toronto, ON, Canada.
Eye Vis (Lond). 2023 Mar 2;10(1):10. doi: 10.1186/s40662-022-00322-1.
Although traditional surgical procedures for glaucoma (such as trabeculectomy and tube-shunt implantation) can significantly reduce intraocular pressure (IOP), they are associated with numerous complications, some of which are vision-threatening, or involve prolonged recovery or a highly intensive postoperative course. Micro-invasive glaucoma surgery (MIGS) procedures have shown better safety but reduced efficacy in achieving target IOP. Combinations of these methods have led to the development of subconjunctival micro-invasive procedures with safety comparable to traditional surgery and greater efficacy than minimally invasive methods. This review describes the use of one of these devices, the poly(styrene-block-isobutylene-block-styrene) (SIBS)-based PreserFlo MicroShunt (Santen, Emeryville, CA), in the surgical treatment of patients with glaucoma.
The MicroShunt is an 8.5-mm tube made of an inert polymer with no endplate, an internal diameter of 70 μm, and fins intended to prevent peritubular flow and anchor the device within the sclera to prevent proximal migration into the eye. Following ab externo implantation, the tube provides a conduit for flow of aqueous humor from the anterior chamber into the subconjunctival/sub-Tenon space. Clinical trials to date have shown that, when paired with mitomycin C (MMC) treatment, MicroShunt implantation significantly reduced both IOP and the number of glaucoma medications. These IOP-lowering results were found both when surgery was performed alone and with phacoemulsification. The MicroShunt also showed a safety profile comparable to that of traditional filtering surgery.
The MicroShunt and other novel subconjunctival procedures have shown substantial IOP reductions while mitigating hypotony-related complications. MMC, which modulates fibrosis and scarring postoperatively, is essential to surgical success. Randomized, long-term clinical trials will further clarify the role of controlled micro-incisional device-assisted ab externo glaucoma filtering surgery in long-term glaucoma management.
尽管传统的青光眼手术（如小梁切除术和引流管植入术）可显著降低眼压（IOP），但它们伴有众多并发症，其中一些会威胁视力，或涉及恢复时间延长或术后病程高度紧张。微创青光眼手术（MIGS）已显示出更好的安全性，但在实现目标眼压方面疗效降低。这些方法的联合应用促使了结膜下微创手术的发展，其安全性与传统手术相当，且疗效优于微创方法。本综述描述了其中一种装置，即基于聚（苯乙烯-嵌段-异丁烯-嵌段-苯乙烯）（SIBS）的PreserFlo微型分流器（参天制药，加利福尼亚州埃默里维尔），在青光眼患者手术治疗中的应用。
微型分流器是一种8.5毫米长的管子，由无终板的惰性聚合物制成，内径为70微米，带有鳍片，旨在防止管周液流并将装置固定在巩膜内，以防止其向眼内近端移位。经外植入后，该管为房水从前房流入结膜下/Tenon囊下间隙提供了一条通道。迄今为止的临床试验表明，与丝裂霉素C（MMC）治疗联合使用时，微型分流器植入术可显著降低眼压并减少青光眼药物的使用量。无论是单独进行手术还是与超声乳化白内障吸除术联合进行手术，均能获得这些降低眼压的效果。微型分流器还显示出与传统滤过手术相当的安全性。
微型分流器和其他新型结膜下手术已显示出在显著降低眼压的同时减轻了与低眼压相关的并发症。MMC可调节术后纤维化和瘢痕形成，对手术成功至关重要。随机、长期的临床试验将进一步阐明可控微切口装置辅助经外青光眼滤过手术在青光眼长期管理中的作用。
