scleral cauterization

Because of its postoperative complications, such as shallow anterior chamber, choroidal detachment, cataract, endophthalmitis, etc., the incidence is higher, so it is not commonly used. However, because of the low level of postoperative intraocular pressure control, it is suitable for some patients who need to control the intraocular pressure, such as normal tension glaucoma. Treatment of diseases: normal tension glaucoma Indication Drug and laser treatments do not prevent glaucoma of various types of progressive optic nerve damage and visual field defects. Due to improvements in surgical techniques and the use of antimetabolites, intraocular pressure levels after trabeculectomy can be similar to those of full-thickness scleral penetrating filtration, so trabeculectomy is now available for almost all needs. Glaucoma for extraocular filtration. Because of its postoperative complications, such as shallow anterior chamber, choroidal detachment, cataract, endophthalmitis, etc., the incidence is higher, so it is not commonly used. However, because of the low level of postoperative intraocular pressure control, it is suitable for some patients who need to control the intraocular pressure, such as normal tension glaucoma. Contraindications Patients with inflammation in the eye need to be treated before surgery. Preoperative preparation Patients should be informed enough about their condition and prognosis. Adjust the preoperative medication. Proine or 1% adrenaline, anti-cholinesterase inhibitors such as iodine phosphate, superior gaze, etc. should be discontinued for two weeks in order to reduce vascular congestion and intraoperative bleeding. The carbonic anhydrase inhibitor and the -adrenergic blocker were stopped for 2 to 3 days, so that the formation of aqueous humor was normal after the operation, which was conducive to the formation of filtration bleb. Antibiotic eye drops such as 0.3% tobramycin were added 3 days before surgery. Gentamicin eye drops may stimulate the bulbar conjunctiva, causing conjunctival hyperemia and avoiding it as much as possible. 1% prednisolone can be started on the day before surgery, 4 times a day. If the patient has not used pilocarpine, use it 1 or 2 times a day before surgery. If the preoperative intraocular pressure is significantly elevated (above 40mmHg), 20% mannitol should be administered intravenously to reduce intraoperative complications. If the patient takes aspirin, it should be discontinued for 5 days. If there are new blood vessels in the iris or anterior chamber angle, panretinal photocoagulation should be performed first to increase the success rate of filtration. Surgical procedure Corneal limbus puncture, sutured rectus muscle traction line and trabeculectomy. 1. Make a bulbar conjunctival flap based on the limbus. The method has been introduced in trabeculectomy. 2. Flip the bulbar conjunctival flap and use a cauterizer to make a slight cauterization of 1 mm x 5 mm at the posterior border of the limbus (Figure 1). 2. The vertical incision parallel to the limbus is then made in the center of the cauterization zone to a depth of approximately 3/4 of the thickness of the sclera (Figure 2). 4. The side edge of the incision is cauterized with a cauterizer to cause the edge of the incision to contract, forming a split of at least 1 mm width (Fig. 3). 5. Turn the blade up and use the tip to pick the remaining 1/4 of the thickness of the sclera (Figure 4). 6. At this time, the outflow of aqueous humor, the iris will naturally come out. If not, remove the posterior lip and let the iris out (Figure 5). 7. Do peripheral iridotomy, the same method as described in trabeculectomy. Restore the iris. 8. The conjunctival flap was repositioned, and the bulbar conjunctiva and the bulbar fascia wound were sutured continuously or intermittently with a 10-0 nylon thread. 9. Inject the balanced saline into the front chamber through the corneal puncture and restore the anterior chamber. complication Shallow anterior chamber, choroidal detachment, cataract, endophthalmitis, etc.