Surgical Options for Glaucoma
Glaucoma surgery has evolved significantly over the past few years, but the surgical therapies still may be put into two categories:
1) Laser Surgery
2) Incisional Surgery
Glaucoma Laser Surgery
Laser Peripheral Irodotomy (LPI)
This form of laser therapy is used to treat patients with narrow angles or acute angle closure glaucoma. In this procedure, your surgeon uses a laser to make a tiny hole in the iris, which allows the aqueous fluid another path to reach the trabecular meshwork.
Laser Trabeculoplasty (LTP)
LTP is used to treat patients with some types of open angle glaucoma. In some instances, patients may elect LTP instead of medications, or to reduce the amount of glaucoma medications they are taking. In LTP, a laser is used to treat the trabecular meshwork, thereby, lowering IOP by increase the amount of fluid that is drained.
Once medical and laser therapies have failed or when they will not work well enough, your doctor may recommend a Trabeculectomy. In this form of surgery, a new drain is made using your eye's tissue. It has been the gold standard in glaucoma surgical therapy for many years, and new improvements, such as the Express Mini-Shunt have made trabeculectomy surgery safer and more predictable.
In this surgery, the conjunctiva (the eye's outer covering) is taken down, and a partial thickness flap is made in the sclera (the white, tough outer covering of the eye). Underneath the scleral flap, the eye is entered allowing a continuous flow of fluid out of the eye. The scleral flap and then the conjunctival tissue are then sutured back into place.
In most cases, your surgeon will use Mitomycin C, which is a chemotherapy agent, to prevent your eye from scarring down the new drain that was surgically developed. In order to allow greater fluid through the new drain, patients most likely will undergo an office based laser procedure to cut some of the stitches in the scleral flap.
One major development and improvement in trabeculectomy surgery is the Express Mini-Shunt. This is a small metallic device that is place underneath the scleral flap during surgery. The shunt allows for a predictable egress of fluid from the eye, thereby reducing some of the complications related to an eye pressure that is too low.
Aqueous Shunts (Tubes)
Another option for glaucoma that cannot be controlled with medications is an aqueous shunt. There are three main types of aqueous shunts that are in use today:
- Baerveldt Implant
- Molteno Implant
- Ahmed Implant
These implants have a plate that is sewn to the sclera, near the insertions of the eye muscles. The tube, which is connected to the plate, is then placed directly into the eye. As a result of this procedure, the aqueous fluid will drain through the tube into the plate, which then allows the fluid to be absorbed by the tissues behind the eye. Tubes have become an increasingly popular treatment for many types of glaucoma, and are considered by many to be safer and more predictable than trabeculectomy surgery.