Deep sclerectomy surgery

The article was professionally consulted with Specialist Doctor I Nguyen Thi Bich Nhi - Ophthalmologist - General Surgery Department - Vinmec Nha Trang International General Hospital.

Primary open-angle glaucoma is a pathological condition of the optic nerve causing damage to retinal ganglion cells and nerve fiber layers, atrophy of the optic disc, a visual field defect typical of glaucoma, often associated with high intraocular pressure. The disease tends to be chronic, so it is important to treat it as soon as possible. Deep sclerectomy is often used to treat primary open-angle glaucoma.

Deep sclerectomy, also known as “non-permeable sclerectomy,” is a glacial surgery that selectively removes the pathological trabeculum that impedes fluid circulation in primary open-angle glaucoma. . The method of deep scleral resection does not penetrate the inner eye, so it is safe and limits complications.
Indications for implementation include:
Primary open-angle glaucoma. pigmented glaucoma. Glaucoma on pseudo-capsular detachment syndrome. Some conditions of open-angle glaucoma secondary to vitreous surgery, prolonged steroid use, are due to congenital factors. Contraindications
Glocom angle closure. Neovascular glaucoma.

Before deep sclerectomy, the patient and family need to know some information as follows:
Implementation team: Including an ophthalmologist and supporting assistant (if necessary). Surgical facilities and equipment: Including microsurgery kits, high magnification surgical microscope... Medicines: antiseptics, anesthetics, anti-metabolites such as Fluorouracil (5FU), MMC. .., injections, post-surgery drugs. Preparation: The patient should be psychologically comfortable and listen to the explanation of the sclerectomy procedure before surgery. Especially, 1-2 hours before surgery, the patient should be given 5% Betadine, antibiotics, and Acetazolamide 0.25g x 2 tablets.

The doctor will perform a deep sclerectomy according to the following steps:
The doctor anesthetizes the patient with local anesthesia or endotracheal anesthesia. To expose the superior margin, place the transcorneal suture (vicryl) close to the superior margin or perforate the superior rectus muscle. Note that if the cornea is placed, 1 or 2 stitches should be placed to reduce the tension, not too close to the edge to hinder the dissection process. The conjunctival opening may be retrograde to the parietal base or the fundus to the margin. Baseline repositioning allows for a larger field of view but requires suture closure at the end of surgery, especially when a calcium channel blocker (CCH) is used. After exposing the sclera, it should be burned to stop bleeding. When hemostasis should be avoided, large water veins should be avoided to preserve natural drainage of aqueous humor. Create scleral flap: The superficial scleral flap measuring 5 x 5mm is dissected, 1/3 - 1/2 depth of the thickness (from 300 - 500mm). Create a scleral flap with dimensions of 4 x 4 mm (this flap must be deep enough to split the Schlemm duct). The remaining sclera is very thin (from 50-100mm). First, make a demarcation of the deep scleral flap, then make a deeper incision at a lateral edge perpendicular to the Schlemm duct until fluid seeps out of the Schlemm duct. From this level continue to dissect the deep scleral flap in two ways: either use a 15 degree knife to dissect (pay attention to tilting the blade upwards to avoid perforation) or use small Vannas scissors to put it straight into the posterior Schlemm canal. Then cut along the sclera spur to split the tube in half. Perform scleral flap resection. Peel off the parietal trabecular layer: blot the surgical area dry, and use surgical forceps to remove the inner wall of the Schlemm canal and the paramural trabecular layer. The suture closes the superficial scleral flap and covers the conjunctiva.

Similar to any other surgery, besides the benefits, deep sclerectomy can also have potential complications such as:
Intraoperative complications: Perforation, tearing of the remaining Descemet basement membrane. Complications after surgery: Leaky bags, inflammatory reactions, low eye pressure. Postoperative glaucoma: may be due to insufficient dissection, hemorrhage in the sclera, laceration of the remaining Descemet basement membrane, secondary steroid-induced glaucoma, infiltrative cystic fibrosis. Late complications: scleral convexity related to arthritis, connective tissue disease. After deep sclerectomy, patients should pay attention to the correct postoperative care regimen: topical antibiotic treatment for the first 2 weeks, local anti-inflammatory therapy for 4-6 weeks, then gradually reduced in 2 months. If you see any unusual signs in your eyes, you should contact your doctor as soon as possible.
Vinmec International General Hospital is one of the hospitals that strictly applies practice standards in surgery, safe surgical anesthesia according to international guidelines. The hospital has a team of qualified doctors and nurses with many years of experience combined with a system of modern equipment and machines that will directly participate in the examination and treatment process. Thanks to the good quality of medical services, customers are completely assured when choosing Vinmec.