Viscoelastic Schlemm Canotomy

Non-penetrating trabeculectomy is a filtering procedure that preserves internal trabeculae but does not penetrate the anterior chamber. Compared with standard penetrating trabeculectomy, it is theoretically more physiologically compatible with aqueous drainage. Different pioneers have proposed different names according to their own developed techniques, such as non-penetrating deep sclerectomy, non-penetrating trabeculectomy, viscoelastic Schlemm tube incision and external trabeculectomy. These names are essentially the same procedure, with external trabeculectomy being the most appropriate, primarily for primary and secondary open angle glaucoma. In 1998, the Frenchman Sourdile improved the NPTS technology combined with the implantation of hyaluronic acid biofilm under the scleral flap, thereby overcoming the proliferation of the fibers under the scleral flap and maintaining the continuous opening of the aqueous decompression chamber under the scleral flap, which improved the success of the operation. rate. Because of the less complications of this procedure, postoperative care is simple and popular with doctors. Treatment of diseases: primary open angle glaucoma Indication Viscoelastic Schlemm tube incision is suitable for primary open angle glaucoma and secondary open angle glaucoma. Surgical procedure The sputum is opened and the rectus pull line is sewed. 1. Make a conjunctival flap based on the upper iliac crest. 2. Make a 5mm × 4mm rectangular scleral flap, about 1/2 scleral thickness, and peel it to 1 ~ 1.5mm in the transparent cornea. 3. Under the rectangular scleral flap, a triangular or semi-arc deep sclerectomy is performed, which is as deep as 90% scleral thickness and 1 to 1.5 mm in the transparent cornea. 4. Remove the outer wall of the Schlemm tube and the tissue outside the tube. Under the microscope, the aqueous humor seeps out from the trabecular meshwork. 5. Inject the viscoelastic material (Helon, Helon GV) into the two ends of the Schlemm tube with a viscoelastic injection needle, and inject the viscoelastic into the aqueous water filter. 6. Stitch the superficial scleral flap 3 to 5 needles and suture the bulbar conjunctiva. complication 1. Postoperative intraocular pressure rise The short-term intraocular pressure rise is mostly due to insufficient cutting of the outer wall and adjacent tissue of the Schlemm tube during operation. The posterior elastic membrane and trabecular meshwork of the surgical field can be perforated using a Nd:YAG laser under a corner mirror. In addition, after the hyaluronic acid gel is implanted, the superficial scleral flap is sutured too tightly, and the intraocular pressure may increase in the early postoperative period. If necessary, the conjunctiva should be opened and 1 to 2 needles of scleral suture removed. In the late stage, the intraocular pressure of the sclera is increased, and it is necessary to add an intraocular pressure-lowering drug. If necessary, surgery is needed again. 2. Postoperative anterior chamber hemorrhage: In the operation of the separation of the inner trabecular and posterior corneal elastic layer, the Schlemm tube is worn or the iris is damaged. If the rupture is larger, the iris can be replaced by trabeculectomy. After the trabeculectomy, the scleral flap should be closed or sutured to prevent the postoperative low intraocular pressure and shallow anterior chamber. The anterior chamber hemorrhage can be absorbed by itself.