Glaucoma Drainage Devices & Tube Shunts in Ahmedabad : Puja Eye Hospital

The plate and tube are implanted beneath the conjunctiva and are generally not visible from the outside. In some patients, a small bulge may be felt or occasionally visible under the eyelid, but this is not typically noticeable in everyday life. The tube itself, which passes through the front of the eye, is very fine and generally not visible without magnification.

Tube shunt surgery and trabeculectomy have somewhat different risk profiles. Tube shunts carry a higher risk of certain complications such as tube-cornea contact over time, but may have a more predictable and durable long-term outcome in certain high-risk eyes. The choice between the two procedures depends on the individual patient’s clinical situation, and Dr. Sheth will discuss the relative risks and benefits before recommending a procedure.

Many patients require fewer eye drops after tube shunt surgery. However, achieving a very low target pressure with a tube shunt alone is not always possible, and supplementary eye drops are often still needed – though typically fewer than before surgery.

Glaucoma drainage devices are designed to be permanent implants. Long-term studies report continued function in the majority of patients at 5 and 10 years after implantation, although some degree of pressure increase over time is common as the body’s healing response gradually encapsulates the plate.

Yes. Tube shunt surgery is frequently performed as a secondary procedure in patients whose trabeculectomy has failed. The device is implanted in a different quadrant of the eye, away from the previous surgical site, where the conjunctiva is unscarred.

A glaucoma drainage device (GDD), also called a tube shunt or aqueous shunt, is a small implant inserted into the eye to create a new, controlled pathway for aqueous humour (the fluid inside the eye) to drain out, thereby lowering intraocular pressure (IOP). The device consists of a silicone tube placed in the anterior chamber of the eye and a small plate sutured to the surface of the eye (sclera) behind the eyelids. Aqueous fluid flows from inside the eye through the tube to the plate, where it is absorbed by surrounding tissue. This effectively bypasses the blocked natural drainage system that causes pressure to rise in glaucoma.

Dr. Puja Sheth recommends glaucoma drainage devices in specific clinical scenarios where standard trabeculectomy has a high risk of failure or has already failed. These include: previously failed trabeculectomy; neovascular glaucoma (arising from diabetic retinopathy or retinal vein occlusion); uveitic glaucoma (glaucoma associated with eye inflammation); aphakic or pseudophakic glaucoma following cataract surgery complications; eyes with significant conjunctival scarring; and some cases of congenital or developmental glaucoma. The choice between a tube shunt and trabeculectomy is made after careful evaluation of the individual patient’s anatomy, previous surgical history, and target IOP requirement.

Puja Eye Hospital offers both valved and non-valved glaucoma drainage devices, including the Ahmed Glaucoma Valve (AGV) and Baerveldt implant, selected based on the clinical indication. The Ahmed Glaucoma Valve contains a pressure-sensitive membrane that prevents excessive drainage immediately after surgery, making it particularly useful in eyes that require careful IOP control in the early post-operative period. The choice of device is individualised by Dr. Puja Sheth based on the type and stage of glaucoma, prior surgical history, and the level of IOP reduction required.

Glaucoma drainage device implantation at Puja Eye Hospital is performed in a modular, NABH-compliant operation theatre. The surgery is typically performed under local or peribulbar anaesthesia with IV sedation, so most patients are comfortable throughout and do not require general anaesthesia. The procedure takes approximately 60–90 minutes. Dr. Puja Sheth places the implant plate beneath the conjunctiva, positions the drainage tube in the anterior chamber, and covers the tube segment with a donor tissue patch to protect it. The eye is patched post-operatively and the patient is reviewed the next day.

Glaucoma drainage devices achieve a clinically meaningful IOP reduction in the majority of patients. Studies show that 70–80% of eyes achieve target IOP with or without adjunctive medications at one year post-surgery. For refractory or complex glaucoma cases where trabeculectomy has failed or is contraindicated, tube shunts offer a reliable alternative route to IOP control. At Puja Eye Hospital, outcomes are carefully monitored with post-operative IOP measurements and OCT at scheduled intervals. Complete surgical success (IOP ≤ 18 mmHg without medications) and qualified success (IOP ≤ 18 mmHg with medications) are the benchmarks Dr. Puja Sheth uses to assess each patient’s result.

As with any intraocular surgery, tube shunt implantation carries risks including: hypotony (excessively low IOP), tube malposition or migration, corneal endothelial damage if the tube contacts the cornea, diplopia (double vision) from plate positioning near extraocular muscles, bleb encapsulation reducing drainage over time, and infection (endophthalmitis, rare). Dr. Puja Sheth discusses all risks in detail during the pre-operative consultation and takes specific surgical precautions to minimise each. The modular OT setup at Puja Eye Hospital, with strict sterility protocols, significantly reduces infection risk.

Most patients experience a recovery period of 4–6 weeks. In the first 1–2 weeks, vision may be blurred and the eye will be on multiple topical medications. Physical activity should be restricted – no heavy lifting, swimming, or rubbing the eye. IOP often fluctuates in the first 4–8 weeks as the bleb around the plate matures. By 8-12 weeks, IOP typically stabilises. Follow-up visits are scheduled at day 1, week 1, weeks 2-4, and monthly for 3 months, followed by 3–6 months of long-term monitoring at Puja Eye Hospital, Naranpura, Ahmedabad.

Many patients require fewer glaucoma medications after tube shunt surgery, and some achieve adequate IOP control without drops. However, the need for adjunctive medication depends on the target IOP, the type of glaucoma, and the extent of nerve damage already present. Dr. Puja Sheth reassesses medication requirements at each post-operative visit, adjusting the regimen based on IOP measurements and optic nerve status. The goal is always the lowest possible IOP with the fewest medications needed to protect remaining vision.