Techniques of Endoscopic Cyclophotocoagulation

Abstract

Inflow reducing surgical procedures have had a sordid history mostly characterized by poor outcomes and substantial complications. Difficulties were mainly due to the lack of direct visualization of the target tissue and by poor control of the destructive force. Collateral damage to healthy tissue from external cyclodestruction leads to significant inflammation and complications. The transvitreal approach to cyclophotocoagulation was first described by Charles, wherein the eye first underwent vitrectomy and lensectomy. The ciliary processes were then scleral depressed into the view of the operating microscope and photocoagulated under direct visualization. The first study of this approach was by Patel and Thompson in a cohort of intractable glaucoma patients treated by this transvitreal method. A high degree of intraocular pressure (IOP) control was obtained with few complications. Unfortunately, this approach to glaucoma treatment is beyond the scope of most ophthalmologists and involves extensive intraocular surgery. Uram devised the notion of combining endophotocoagulation with endoscopic imaging and demonstrated the ability to access the ciliary processes and photocoagulate them from both a limbal or a pars plana approach and circumventing their lens status, whether phakic, pseudophakic, or aphakic. He described the application of endoscopic cyclophotocoagulation (ECP) across an array of glaucoma mechanisms and levels of severity. Since that time, numerous reports have corroborated the initial findings so that today ECP is the most commonly performed inflow reducing procedure in the United States. | TECHNOLOGY