Eyeworld

49 EW FEATURE February 2019 • Facing complicated glaucoma cases larger clefts can be fixed with sutur- ing, he said. Endoscopy also helps when placing a large capsular tension ring in the sulcus and stretching it out to push to the ciliary body against the sclera and let it heal. Dr. Sarkisian uses the endoscope to visualize the angle better in select cases of MIGS if the cornea is too cloudy. "It is difficult to use it routinely, as the probe moves within the eye and you don't have a third hand to keep things still with your probe hand while the dominant hand implants a device or performs a pro- cedure," Dr. Sarkisian said. Dr. Fellman has found the camera portion of the endoscope especially useful in complex glau- coma cases due to altered anterior segment anatomy, such as in trauma or secondary glaucoma cases. "Most tubes are positioned in the anterior chamber, but occa- sionally, the chamber is too narrow or anatomically disrupted for the tube and the camera portion of the endoscope allows the surgeon to see 'around corners,'" Dr. Fellman said. "This greatly facilitates accurate tube positioning in the posterior chamber or even the vitreous cavity during surgery." Additionally, once the tube is in position, tilting the endoscope light creates an oblique view of the tip of the tube, which accentuates the definition of clear tissue, such as vitreous, he said. "In patients with a preexisting tube where the IOP has suddenly become uncontrolled and the tube is not well visualized at the slit lamp, the endoscope allows visual- ization of the tip of the tube in the operating room and may explain the reason for the raised IOP," Dr. Fellman said. IOL surgery Dr. Fellman has found the camera portion of the endoscope is often useful in identifying abnormalities associated with positioning of the IOL. "When a malpositioned haptic or subluxated IOL is suspected behind the iris but not easy to see at the slit lamp, the endoscope camera and light are useful to further delin- eate the anatomy surrounding the IOL," Dr. Fellman said. It also is useful when a part of the IOL is thought to be eroding the adjacent iris but can't be seen during a slit lamp exam. "Thus, the position of the IOL during any intraoperative procedure can be highlighted with the endo- scope revealing a variety of mala- dies," Dr. Fellman said. In basic IOL surgery, Dr. Francis said endoscopy allows surgeons to see not only the capsular support but the zonular support. "We've seen cases where the anterior capsule is completely intact and yet we have a patient referred to us with a sun setting IOL, and only with an endoscope can you see that the capsule is there but there's a lot of zonules missing so the lens is ba- sically slipping past the zonules and around the edge of the capsule," Dr. Francis said. For removal of iris-sutured IOLs where there is potential bleeding in the eye due to the lens, Dr. Francis uses the endoscope to help ap- proach posteriorly and remove the sutures without damaging the iris or the IOL. "The endoscope is useful when you don't know what is going on with the IOL or you are not sure what is going on peripherally with the IOL," Dr. Francis said. Endoscopic vs. transscleral cyclophotocoagulation Dr. Sarkisian said ECP is commonly performed with cataract surgery and is much less inflammatory than transscleral cyclophotocoagulation (TSCPC). He uses ECP for all stages of glaucoma, including mild to moderate glaucoma where main- taining vision is paramount. Traditionally, TSCPC been a last resort for end stage glaucoma and for severe glaucoma due to its ability to process more efficiently. MicroPulse laser cyclophotoco- agulation (Iridex, Mountain View, California) may be less inflamma- tory and detrimental to vision than earlier TSCPC, Dr. Francis said. He often uses it after finding aqueous production. Dr. Fellman said TSCPC is a safer alternative if the risk of in- traocular cyclodestructive surgery outweighs the benefits. "For example, some patients are too sick for intraocular surgery, or they may have a significant bleeding diathesis, or the risk of ocular infection is too high; these patients are candidates for transs- cleral cyclophotocoagulation," Dr. Fellman said. "Transillumination of the globe directly prior to transs- cleral cyclophotocoagulation may help delineate the anatomy of the anterior segment, allowing for a more accurate application of the laser energy to the area of the ciliary body processes." EW Reference 1. Francis BA, et al. Endoscopic cyclopho- tocoagulation (ECP) in the management of uncontrolled glaucoma with prior aqueous tube shunt. J Glaucoma. 2011;20:523–7. Editors' note: Drs. Fellman and Francis have financial interests with Beaver- Visitec International. Dr. Sarkisian has no financial interests related to his comments. Contact information Fellman: rfellman@glaucomaassociates.com Francis: bfrancis@doheny.org Sarkisian: drsarkisian@okeyesurgeons.com

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