All about iStent treatment for glaucoma

Glaucoma is one of the leading causes of irreversible blindness in the UK. While often manageable with early detection and treatment, some patients require more advanced interventions to preserve their sight. One such option is the iStent, a tiny implant that helps to lower eye pressure in people with glaucoma. This article from Miss Samantha Levin, a consultant ophthalmologist, explains how the iStent may offer a safe and effective alternative treatment for glaucoma.

What is glaucoma?

Glaucoma is a group of eye conditions that damage the optic nerve, the part of the eye that sends visual signals to the brain. This damage is most often caused by increased intraocular pressure, which occurs when fluid in the eye does not drain properly.

Normally, this fluid flows through a drainage system within the eye. With glaucoma, this system becomes blocked or inefficient, causing pressure to build up. Over time, this pressure damages the optic nerve, leading to gradual vision loss.

Glaucoma is often called the “silent thief of sight” because it can progress without noticeable symptoms. In the early stages, peripheral vision is affected, which may go unnoticed. If left untreated, glaucoma can lead to tunnel vision and eventually complete blindness.

Treatments for glaucoma and their limitations

The primary goal in treating glaucoma is to lower intraocular pressure and slow or halt nerve damage. Common treatments include:

• Eye drops: The most frequently used first-line treatment. These reduce fluid production or increase drainage.
• Laser therapy: This helps improve fluid outflow.
• Surgery: Traditional surgery (such as trabeculectomy) is considered when medications and laser fail to adequately control pressure.

While effective, medications must be used consistently and can have side effects such as eye redness, irritation, or systemic effects in rare cases. Laser treatments may wear off over time, and traditional surgery, though highly effective, carries risks such as infection or significant changes in eye pressure.

This is when ophthalmologists may explore minimally invasive glaucoma surgery (MIGS), including the iStent.

What is the iStent for glaucoma?

The iStent is one of the smallest medical implants ever approved for use in the human body. It is a tiny titanium tube that is inserted into the eye’s natural drainage system. Once in place, it creates a permanent channel that allows fluid to bypass the blockage and drain more easily, reducing eye pressure.

The iStent is typically used in patients with mild to moderate open-angle glaucoma and is often implanted at the same time as cataract surgery. The procedure is quick, usually taking only a few minutes longer than standard cataract surgery. Because the iStent is placed through a small incision without the need for stitches, the recovery is generally swift.

Following the iStent procedure, most patients can go home the same day. They are prescribed anti-inflammatory and antibiotic eye drops to aid healing and prevent infection. Follow-up visits are scheduled to monitor intraocular pressure and ensure the device is functioning correctly.

Patients often experience a reduction in eye pressure and, in some cases, can reduce or stop their glaucoma eye drops. However, the iStent does not cure glaucoma or reverse any vision loss that has already occurred.