goniectomy

Congenital glaucoma is caused by dysplasia of the anterior chamber angle during the fetal period, and is mostly present at birth. Because the eye wall of infants and young children is easily expanded by the action of high intraocular pressure, the whole eyeball is continuously enlarged, so it is called "water eye". Congenital anomalies of the anterior chamber are mainly: 1 anterior chamber angle structure is not developed or underdeveloped, scleral sinus and trabecular mesh occlusion; 2 ciliary muscle front end beyond the scleral process, into the trabecular tissue or sinus; 3 rooms The horn is covered by a layer of mesenteric residual membrane, which causes the outflow of aqueous humor to be blocked and the intraocular pressure to rise. Under the effect of sustained high intraocular pressure, the eye wall expands and the rear elastic layer ruptures, resulting in strip turbidity. The angle of the sclera is widened and thinned, and its width can reach more than 5mm. The anatomical landmarks of the limbus and their relative relationships also change greatly. Congenital glaucoma should be treated surgically in the early stage. The purpose is to cut the residual membrane of the mesoderm in the corner of the anterior chamber and reduce the resistance of the aqueous efflux. It is especially effective for children with a complete development of the anterior chamber. The currently used surgery is anterior chamber angle incision and external trabeculectomy. The success rate of anterior chamber angle surgery was 50% on average, and it was reported to reach 70%. The success of the operation is that the optic nerve injury is stopped, the optic cup is no longer enlarged, the corneal edema subsides, and the visual acuity is restored. However, because of poor child cooperation and inconvenient examination, intraocular pressure is still one of the important indicators for determining the effect of surgery. In recent years, dynamic visual field examination and visual evoked potential examination have been used to evaluate visual function status. The success rate of 2 to 3 operations was 75 to 95%. There were other abnormalities in the eye and general anomalies, and the surgical results were poor. In 5% of children, the intraocular pressure increased significantly within a few years after surgery. Treatment of diseases: congenital glaucoma congenital cataract Indication 1. Corneal transparent infant congenital glaucoma. 2. With neurofibromatosis, lowe syndrome, congenital aniridia. Congenital glaucoma with axenfeld syndrome and iris trabecular hypoplasia. 3. Secondary to glaucoma in children with rubella, congenital cataract surgery, and chronic anterior uveitis. Contraindications 1, children and adolescents with a higher age of onset, corneal diameter of more than 15mm, the cornea has been significantly turbid. 2, the cornea is white turbid. Preoperative preparation 1. Introduce the surgical goals and possible risks to the parents in order to get their support and cooperation. 2. Pay attention to whether the child's nasal lacrimal duct is smooth. 3. Preoperative eye drops with antibiotic eye drops. 4. Dilute 1% pilocarpine 1 hour before surgery to reduce the pupil. 5. If corneal edema, anti-ocular pressure medication can be applied, and the cornea is transparent before surgery. If it is only corneal epithelial edema, some corneal epithelium can be removed after surgery and anterior chamber angle incision can be performed. 6. Amplification equipment and anterior chamber angle cutting knife (1) A binocular magnifier with a magnification of 2 times, or a surgical microscope with coaxial illumination, 6 to 20 times magnification, and a mirror axis of 30 to 60 degrees can be selected. (2) anterior chamber angle mirror for surgery: commonly used are barkan type, worst type and swan-jacob type. (3) anterior chamber angle incision knife: commonly used barkan, swan and swan needle type anterior chamber angle incision knife. (4) Opener for children, and self-locking fixation. Surgical procedure 1. The surgeon sits on the side of the eyelid, and the head of the child is deflected to the opposite side of the surgeon by an angle of 30° to 40°, so that the anterior chamber corner portion to be cut can be directly seen through the microscope eyepiece. 2. Open the device. Check the cornea. If there is corneal edema, drop 1-2 drops of pure glycerin to keep the cornea dehydrated, or scrape the edema of the corneal epithelium. 3. Use the gingival cap to clamp the angle of the limbus and rotate the eyeball so that the upper rectus muscle and the inferior rectus muscle are clamped by the self-locking fixation. 4. Gently place the anterior chamber angle mirror (with the barkan front angle mirror as the side) on the cornea. The mirror should be biased toward the nasal side of the cornea so that the anterior chamber angle incision enters the anterior chamber from the half-moon portion of the exposed temporal cornea about 2 mm wide. The operator's left hand indicator can fix the anterior chamber corner mirror. 5. The anterior chamber angle incision knife penetrates the cornea 1 mm from the temporal margin of the temporal margin, parallel to the iris surface, and slowly advances across the pupil area to the nasal anterior chamber angle. Pay attention to the direction of the feed. 6. Look at the anterior chamber angle and cut the tip so that it reaches the first 1/3 of the trabecular meshwork. Pierce into the 4 o'clock position (right eye) about 0.5mm inside the trabecular meshwork, turn the knife tip against the clock, and slowly cut the trabecular tissue. The cutting range is approximately 120°. 7. The surgeon should see the incision after the tip of the knife. At this time, it can be seen that the root of the iris is retracted backward, and the local anterior chamber is widened, and the incision tissue is a pale gray-white tissue boundary line. 8. After the anterior chamber angle is cut, remove the anterior chamber angle and cut the knife. 9. Check that the corneal incision is good, otherwise a 10-0 suture can be sutured with a 10-0 nylon thread.