CO₂ laser‐assisted sclerectomy surgery compared with trabeculectomy in primary open‐angle glaucoma and exfoliative glaucoma. A 1‐year follow‐up

Abstract

Although CLASS shows a less potent hypotensive effect, it is similar to trabeculectomy in the qualified success rate and offers the reduction in medications up to 12 months. With a more attractive complications profile, CLASS may be an alternative to trabeculectomy, especially at the earlier glaucoma stage and in patients with a low ECD.

Safety and Efficacy of Scleral Concave Pool Trabeculectomy Combined Phacoemulsification for Eyes with Coexisting Cataract and Primary Open Angle Glaucoma.

“…The CLASS procedure, which showed a similar qualified success rate and reduction in medications compared to conventional trabeculectomy, may be an alternative to trabeculectomy when considering the postoperative complications [8,10,22,23] . During the CLASS procedure, a reservoir is formed by using the CO 2 laser to ablate the scleral tissue [8] .…”

“…The CLASS procedure, which showed a similar qualified success rate and reduction in medications compared to conventional trabeculectomy, may be an alternative to trabeculectomy when considering the postoperative complications [8,10,22,23] . During the CLASS procedure, a reservoir is formed by using the CO 2 laser to ablate the scleral tissue [8] . To our knowledge, a reservoir allowing the percolated aqueous accumulation may have the advantage of keeping the filtering path unobstructed by the following pathways: 1) Filling the bleb with aqueous humor all the time which then help maintain the tension of bleb; 2) Help regulate the flow of liquids so that when the flow speed is low in the drainage, the accumulated aqueous humor in the reservoir can offer a replenishment of liquid; 3) Keeping the path filled with liquid flow can help wash away inflammatory factors.…”

“…To our knowledge, a reservoir allowing the percolated aqueous accumulation may have the advantage of keeping the filtering path unobstructed by the following pathways: 1) Filling the bleb with aqueous humor all the time which then help maintain the tension of bleb; 2) Help regulate the flow of liquids so that when the flow speed is low in the drainage, the accumulated aqueous humor in the reservoir can offer a replenishment of liquid; 3) Keeping the path filled with liquid flow can help wash away inflammatory factors. The CO2 laser, which can be largely absorbed by water, has little direct effect on the angle tissue when the aqueous starts to percolate [8,10] , However, the IOPtiMate system used in the CLASS procedure is too expensive for its wide spread application in developing countries such as China.…”

“…However, the inavailability of adjunctive antifibrotic agents such as 5-FU and MMC in China sparks an emergency requirement for the improvement of trabeculectomy technique. Improvement of techniques, such as deep sclerectomy (DS) and CO 2 laser-assisted sclerectomy surgery (CLASS) has reduced the complication rates in treating open angle glaucoma [6][7][8] . Contrary to trabeculectomy, DS, which does not require penetrating the anterior chamber, has been reported to improve the safety of glaucoma surgery with high success rate, but it requires considerable technical skills to preserve the integrity of the trabeculo-Descemet's membrane (TDM) [6,9] .…”

“…Recently, a newly developed technique, CLASS, which performs deep sclerectomy down to the TDM by CO 2 laser application on the scleral bed after a half thickness scleral flap is created, has been reported as a feasible and apparently safe procedure [8,10] . However, the IOPtiMate system used in the CLASS procedure is too expensive for its wide spread application in developing countries such as China.…”