Cutting Edge Glaucoma - Issue 2

CHILDHOOD GLAUCOMA SURGERY IN DEVELOPING COUNTRIES • 13  As the probe passes into the AC, minimal resistance is felt while disrupting the inner wall of the canal. There may be minimal intracameral bleeding from the inner wall, leaving a small hyphema that often resolves in a few days. 10. The probe is swept in a plane parallel to the iris. If done incorrectly, this may cause iridodialy- sis. Anterior rotation can cause trauma to the Descemet membrane. 11. The trabeculotomy has been completed and now trabeculectomy has to be performed. The deep block is excised using Vannas scissors. 12. An iridectomy is then completed. It is imperative that the base of the iridectomy opening is wider than the trabeculectomy opening to prevent ostium block and iris pillar attachment to the ostium causing pupillary peaking. 13. The scleral flap is then closed with one to three 10-0 nylon sutures, one at the apex and one on each lateral side of the triangular flap. The knots should be buried to avoid later exposure through the conjunctival tissue. 14. Conjunctiva and Tenon capsule are then closed with a running suture of an absorbable mate- rial (e.g., 8-0 vicryl). 15. In highly buphthalmic eyes, Schlemm canal may not be located with certainty. In such cases it is possible to convert the procedure to a trabeculectomy despite the lack of successful trabeculotomy. 16. Some surgeons prefer to perform a paracentesis opening with a beveled corneal incision at the beginning of the surgery. In such a situation, the anterior chamber is reformed with balanced salt solution, and patency of the trabeculectomy can be tested at the conclusion of the surgery. The authors, however, do not prefer making a paracentesis opening. 17. If bilateral surgery is needed, both procedures are performed at the same operating sessions, although an entirely different set of draping, gloves, drops, instruments, and irrigating solu- tions for each eye is necessary. 18. Subconjunctival dexamethasone injection (0.2 ml) is given, and a drop of cycloplegic and antibiotic is instilled into the conjunctival sac before a patch and shield are applied to the eye. Refer to Video 1 for the surgical technique of primary CTT on a 3-month-old child with primary congenital glaucoma. When primary surgery fails, medical treatment may be initiated with topical carbonic anhy- drase inhibitors, beta-blockers, and prostaglandin analogues (in that order) after ruling out con- traindications. If the medical treatment is ineffective, either trabeculectomy with antiscarring agents or a GDD is our next choice based on the health of the conjunctiva and severity of the disease. We consider trabeculectomy with MMC (0.4 mg/ml for 2 min) in the superotemporal or superonasal quadrant with unscarred conjunctiva. When trabeculectomy fails, bleb needling with adjunctive antimetabolite use is an option, especially if the sclerostomy is patent and the flap edge is visible [36]. Glaucoma Drainage Device (GDD) Surgery Glaucoma drainage devices are indicated when primary surgery fails or in certain secondary glau- comas even as a primary procedure. However, in certain parts of the developing world, the cost