Commentary: Combined cataract extraction with a new nonvalved glaucoma drainage device in adult eyes with cataract and refractory glaucoma.

Dr. Rao and Dr. Pathak-Ray have provided a comprehensive review and insight into the first indigenously designed Aurolab aqueous drainage implant (AADI) valve and its use in patients with recalcitrant glaucoma with concurrent cataract.[1] The AADI is based on the Baerveld prototype except that it is not impregnated with Barium (which was done to keep the object radiographically identifiable).

It is good to have a low-cost, made-in-India valve that is easily accessible to glaucoma surgeons. The tube versus trabeculectomy study indeed put tubes ahead of the trabeculectomy.[2] A study by Wilson on a population similar to ours, however, found them to be equally efficacious.[3] Hence, at the current level of understanding, and in a country like ours, the use of tubes should be encouraged in situations where trabeculectomy may not be a primary option.

Fibrin glue as used in this study may add to the expenses. Instead of using a corneal button or preserved sclera, a carefully dissected lamellar scleral pocket can safely cover the tube.[4] A very interesting finding in this study is the rarity of choroidal detachment and hypotony which generally accounts to 6%–25% of complications in other study that we have reviewed.[56] The reason for this is difficult to understand, but it could be related to extremely good vents such that the intraocular pressure never really was too high, thus the sudden lowering did not happen. This would be really important, especially in the combined cases as a shallow anterior chamber would not only push the valve forward but the intraocular lens could also touch the endothelium. An important point to remember is that unless an excellent venting is done, the intraocular pressure may remain high initially for about 6 weeks, which could further spike by steroid use post cataract surgery. Hence, if the glaucoma is advanced, one may choose this device with extreme caution.