Glaucoma Surgery (Trabeculectomy)

What is Glaucoma Surgery?

Glaucoma Surgery (Trabeculectomy) is a microsurgical procedure performed to relieve elevated intraocular pressure (IOP) caused by impaired aqueous humor fluid drainage inside the eye. Uncontrolled IOP damages the delicate optic nerve fibers, leading to progressive, permanent peripheral vision loss. Trabeculectomy creates a small drainage flap (a "bleb") in the sclera (white part of the eye), allowing fluid to bypass blocked natural channels and drain beneath the conjunctiva.

Who Needs Glaucoma Surgery?

Glaucoma surgery is recommended when conservative medical treatments (prescription eye drops) or laser therapies fail to adequately control intraocular pressure or stop optic nerve damage.

Key clinical indicators include:

• High Intraocular Pressure (IOP) persisting despite maximum tolerated medical therapy.
• Progressive visual field loss (tunnel vision) documented on perimetry tests.
• Optic nerve head cupping or nerve fiber layer thinning on OCT scans.
• Poor patient compliance or severe allergic reactions to long-term glaucoma eye drops.
• Advanced primary open-angle or angle-closure glaucoma requiring target IOP reduction.

Types of Glaucoma Procedures

• Trabeculectomy: The gold-standard filtering procedure that creates a guarded flap in the sclera for fluid drainage.
• Glaucoma Drainage Devices (Tube Shunts / Valves): Implantation of a flexible micro-tube (e.g., Ahmed Valve) attached to a reservoir plate for refractory glaucoma cases.
• Minimally Invasive Glaucoma Surgery (MIGS): Microscopic implants (e.g., iStent) inserted into natural drainage pathways, suitable for mild-to-moderate glaucoma.
• Laser Trabeculoplasty (SLT/ALT): Non-surgical laser treatment used to clear trabecular meshwork channels prior to micro-surgery.

Benefits of Glaucoma Surgery

1. Significant and sustained reduction of Intraocular Pressure (IOP).
2. Prevents or halts further irreversible optic nerve damage and vision loss.
3. Reduces or eliminates the daily need for multiple expensive glaucoma eye drops.
4. Protects remaining functional field of vision for long-term independence.

What to Expect Before Surgery?

Comprehensive diagnostic mapping guides surgical planning:

• Visual Field Testing (Perimetry): Mapping peripheral vision defect boundaries.
• OCT Optic Nerve Scan: Quantitative structural analysis of retinal nerve fiber layers.
• Gonioscopy: Direct evaluation of anterior chamber drainage angle geometry.
• IOP Monitoring: Serial pressure recordings across different times of day.

Complete Procedure

The surgical steps for Trabeculectomy involve:

1. Administering peribulbar or local anesthesia to thoroughly numb the eye.
2. Making a small incision in the conjunctiva near the top of the eye under the upper eyelid.
3. Creating a partial-thickness scleral flap (hinged door in the white wall of the eye).
4. Applying Mitomycin-C (MMC) micro-sponges to prevent post-operative scarring.
5. Removing a tiny piece of tissue (sclerotomy and peripheral iridectomy) to establish fluid flow.
6. Suturing the scleral flap loosely with micro-stitches to regulate outflow.
7. Closing the conjunctiva securely to form a fluid collection reservoir (bleb).

What to Expect During Surgery?

The surgery lasts approximately 45 to 60 minutes. Local anesthesia ensures you feel no pain. You may remain in the day-care recovery room for a few hours before returning home with an eye patch.

Trabeculectomy vs Tube Shunt vs MIGS

Success Rate and Safety

Trabeculectomy has an initial success rate of 80% to 90% in lowering IOP to safe target levels. Long-term monitoring ensures the drainage bleb functions effectively.

Glaucoma Surgery Cost Estimate

Disclaimer: Costs vary depending on implant devices, surgeon expertise, hospital stay requirements, and follow-up care.

Recovery Guide & Post-Operative Care

Recovery Timeline

• Week 1-2: Vision may be temporarily blurry; IOP drops significantly; frequent follow-up visits.
• Week 3-6: Bleb stabilization; selective removal or loosening of laser flap sutures if needed.
• Month 2-3: Final pressure stabilization; resumption of routine non-strenuous activities.

Post-Op Precautions & Care

• No Heavy Straining: Avoid coughing, bending over, or lifting objects >3 kg to prevent pressure spikes.
• Strict Drop Hygiene: Use prescribed steroid and antibiotic eye drops rigorously.
• Eye Shield: Wear a rigid eye shield while sleeping for 3–4 weeks.
• Infection Watch: Seek immediate medical care if you notice severe pain, discharge, or sudden vision drops.