iStent Micro Invasive Glaucoma Surgery
How the iStent Works
This section explains why the iStent is placed, how it functions inside the eye, and what patients can expect from the procedure.
In healthy eyes, aqueous humor exits through the trabecular meshwork into Schlemm’s canal to keep pressure balanced. Open-angle glaucoma blocks this pathway, raising eye pressure. The iStent bypasses the blockage and restores outflow through the natural channel.
The surgeon inserts the iStent through a tiny incision, usually during cataract surgery. Once positioned in the trabecular meshwork, the device directs fluid into Schlemm’s canal while preserving eye anatomy.
The surgery is performed under local anesthesia, adds only a few minutes to cataract removal, and most patients return home the same day with little discomfort.
The iStent provides a modest pressure reduction and is not meant for advanced glaucoma or cases requiring very low target pressures.
Key Benefits of the iStent
Placing an iStent offers several advantages that can simplify glaucoma management and improve quality of life.
The implant is delivered through microscopic incisions, leading to less tissue trauma and milder postoperative discomfort compared with traditional surgeries.
Because the approach is micro-invasive, healing is quicker and vision often stabilizes within days rather than weeks.
Many patients find they need about half to one fewer glaucoma drops per day, which eases routines and minimizes side effects.
Constructed from titanium, the iStent is considered MRI-conditional up to 3 Tesla. Patients should inform radiology staff about the implant before imaging.
The device works with the eye’s existing drainage system, keeping future treatment options open and avoiding creation of new outflow pathways.
Comparing iStent With Other Glaucoma Treatments
Understanding how the iStent fits among current therapies helps set realistic expectations.
The iStent involves smaller incisions and fewer complications than trabeculectomy or tube shunt procedures, though its pressure-lowering effect is also smaller.
Most patients resume normal activities sooner than those who undergo more extensive surgeries.
Individuals with severe glaucoma who require very low pressures may still need more aggressive treatments.
While many patients cut back on drops, complete freedom from medications is uncommon.
Ideal Candidates for iStent
The best results occur in carefully selected patients whose glaucoma and cataract needs overlap.
Patients using two or more pressure-lowering drops yet still above target pressure may benefit.
The implant is typically placed during cataract removal, offering a combined solution in one procedure.
Those with dry eye or irritation from long-term drops appreciate reducing medication load.
Individuals with optic-nerve changes and minimal visual field loss often experience safe pressure control with the device.
Because the stent leaves key structures intact, it keeps options open for future interventions if needed.
Before Your iStent Procedure
Proper preparation supports a smooth surgery and recovery.
A pre-operative visit reviews medical history and current eye drops, and instructions are given about fasting or pausing certain medicines. Patients arrange transportation home after surgery.
On arrival, the eye is numbed with drops or a small injection. The iStent is placed during cataract removal through the same micro-incision.
Post-Procedure Care and Recovery
Knowing what to expect afterward helps patients heal confidently.
A protective shield may cover the eye. Mild redness, blurred vision, and discomfort are normal for a few days, and antibiotic as well as anti-inflammatory drops are prescribed.
Most vision fluctuation settles within days to weeks, recovery is faster than with traditional glaucoma surgery, and regular follow-up visits ensure the stent is working properly.
All surgeries carry risks, though serious complications are uncommon.
- Temporary blurred vision, redness, or discomfort
- Eye inflammation, bleeding, or infection
- Stent blockage, movement, or scar tissue formation
- Elevated or uncontrolled pressure that may need further treatment
- Rare issues such as corneal swelling or retinal detachment
Advancements in the iStent Family
Newer versions offer expanded options while maintaining a minimally invasive profile.
This model places two smaller stents in different locations of Schlemm’s canal during cataract surgery to promote multi-directional fluid flow. Safety and recovery are similar to the original device.
Approved for use with or without cataract surgery, this implant accesses up to 240 degrees of Schlemm’s canal and aims for longer-term pressure control, though studies continue to track durability.
Recovery Timeline
Most patients experience a predictable sequence of healing milestones.
Mild discomfort, blurred vision, or redness typically resolve within a few days.
Patients go home the same day with instructions to avoid rubbing the eye and to use prescribed drops.
Clearer vision usually returns within a week, though some blurriness can last up to two weeks as the eye adjusts.
An appointment within the first week checks healing and pressure, with additional visits scheduled as needed.
Lifestyle After iStent
With proper precautions, most daily activities resume quickly.
Reading, showering, and computer use are generally safe the next day, but avoid eye rubbing for about two weeks.
Many people return to work within a few days, depending on job demands.
Driving may resume once vision is clear and the surgeon approves, typically within a few days.
Light exercise is allowed after a few days, but postpone heavy lifting or strenuous workouts for two weeks.
Avoid pools, hot tubs, and open water for at least two weeks to prevent infection.
Hold off on eye makeup for one week or as directed to reduce irritation.
Air travel is generally safe after the first post-op visit once the ophthalmologist confirms healing.
Frequently Asked Questions
The answers below address common concerns about the iStent.
No. The implant is so small and made of titanium that it does not trigger security alarms.
Yes. It is considered MRI-conditional up to 3 Tesla. Always inform radiology staff about the implant.
No. Patients neither see nor feel the device once it is in place.
The iStent is intended to stay in the eye permanently, but a surgeon can remove or reposition it in rare situations.
Previous glaucoma surgery may reduce effectiveness. Your surgeon will evaluate your eye and recommend the best option.
The implant is designed for long-term use and continues to aid fluid outflow for many years.
Most U.S. insurance plans, including Medicare, cover the iStent when combined with cataract surgery for eligible patients, but policies vary.
Many patients notice lower pressure within the first week, with continued stability over the next few months.
Yes. Surgeons sometimes pair the iStent with other minimally invasive procedures to achieve optimal pressure control.
Absolutely. Ongoing exams monitor pressure, optic nerve health, and the function of the implant.
Find Out If iStent Is Right for You
A comprehensive examination will determine the most appropriate treatment for your glaucoma. Our team is ready to evaluate your specific needs and discuss whether the iStent or another option can best protect your vision.
Dr. Chin is kind, professional, and provides thorough care. I recently had laser surgery for glaucoma and I’m very pleased with the results.
Michele Cucci
Dr. Chin is kind, professional, and provides thorough care. I recently had laser surgery for glaucoma and I’m very pleased with the results.
Michele Cucci
Went for my checkup. Good knowledgeable staff, everything went well. It’s always good to see Dr. Lee. He cares about his patients—highly recommend him.
Newton Sweet
Dr. Bianchi was wonderful with my six-month-old daughter. At the last minute he helped with an eye problem I was having. He is a great eye doctor, I would recommend him to others!
Casey Sudol
Seemed very knowledgeable and attentive to my concerns. Would not hesitate seeing him again or recommending him to others.
AA