YAG laser: capsulotomy and iridotomy explained
A YAG laser delivers very short pulses of focused light that make a tiny opening in tissue inside the eye, without a cut. It is used for two different procedures: one for cloudiness that can develop behind a lens implant after cataract surgery, and one for narrow drainage angles. Both are performed at Dr. P. Siva Reddy Eye Hospital as outpatient procedures.
In brief
| YAG capsulotomy | YAG peripheral iridotomy | |
|---|---|---|
| Who it is for | People whose vision has clouded again after cataract surgery because the membrane behind the lens implant has turned cloudy | People with narrow drainage angles, or who have had or are at risk of angle closure |
| What it does | Makes an opening in the cloudy membrane so that light passes through | Makes a small opening in the outer iris so that fluid can pass through |
| The laser itself | A few minutes | A few minutes |
| Afterwards | Blur for a few hours, floaters for some days | Blur and mild ache for a day or two |
| Main limits | Clears only the blur caused by the membrane | Lowers the risk of angle closure. It is not a cure for glaucoma |
YAG capsulotomy
Who it is for
In cataract surgery, the cloudy natural lens is removed and a lens implant is placed inside the thin, clear membrane that held the natural lens. This membrane is called the capsule. In some eyes, months or years later, cells grow across the back of the capsule and it turns cloudy. This is called posterior capsule opacification. It is a known and common late effect of cataract surgery, not a fault in the operation or the implant.
The symptoms come on gradually: blurred or misty vision, glare from lights, difficulty with night driving or reading. They resemble the original cataract, which is why people often think the cataract has returned.
Laser is advised when the cloudiness is affecting your vision or daily activities, or when it prevents the doctor from seeing the retina clearly. A cloudy capsule that is not causing difficulty can be left alone and watched.
What happens
- Your vision and eye pressure are checked, and the eye is examined to confirm that the capsule is the cause of the blur.
- Drops are put in to widen the pupil. A drop to limit any rise in eye pressure may also be used.
- Numbing drops are put in. You sit at the laser, which looks like the examination microscope, with your chin on the support.
- A small contact lens may be placed on the eye to steady it and focus the laser.
- The doctor delivers a series of laser pulses. You hear clicks and see flashes of light. You need to keep still and look where you are asked.
- The lens is removed and your eye pressure is checked again after a wait.
Recovery
- Vision is blurred for a few hours and then usually clears over the following day or days.
- Floaters are common at first and usually become less noticeable over a few weeks.
- Anti-inflammatory drops may be prescribed for a short course.
- Most people return to ordinary activities the next day.
- A review visit is arranged as advised.
Risks and limits
- A rise in eye pressure. This is usually temporary and is the reason pressure is checked afterwards. People with glaucoma are watched more closely.
- Floaters. Common and usually fade, though a few can persist.
- Inflammation inside the eye. Usually mild and treated with drops.
- Small marks on the lens implant. These can occur and usually do not affect vision.
- Swelling at the centre of the retina. Uncommon. It causes blurred central vision in the weeks after laser and is treatable.
- Retinal detachment. Rare, but serious. The risk is higher in very short-sighted eyes. A sudden shower of floaters, flashes of light, or a curtain or shadow in the vision needs an examination the same day.
- Movement of the lens implant. Rare.
- The limit of the procedure: it removes the blur caused by the cloudy capsule and nothing else. Vision afterwards depends on the health of the rest of the eye.
YAG peripheral iridotomy
Who it is for
Fluid is made inside the eye continuously and drains out through a channel in the angle between the iris, the coloured part of the eye, and the cornea, the clear window at the front. In some eyes this angle is narrow. If the iris closes the angle off, fluid cannot drain and the pressure rises. It can rise slowly over time, or suddenly in what is called an acute angle-closure attack, with severe eye pain, headache, blurred vision, coloured rings around lights and nausea.
A narrow angle is found during an examination, using a special lens to look at the angle. It usually causes no symptoms beforehand. An iridotomy may be advised:
- after an angle-closure attack, in that eye and usually in the other eye as well
- when the angle is closed or closing and the pressure or the optic nerve is affected
- in some eyes with narrow angles that are judged to be at risk
Not every narrow angle needs laser. Some are watched. The doctor explains the reasoning for your eye.
What happens
- Drops are put in to make the pupil small, which stretches the iris thin. These drops can cause a brow ache and dim, blurred vision for some hours.
- A drop to limit any rise in eye pressure may be used, and numbing drops are put in.
- You sit at the laser with your chin on the support. A small contact lens is placed on the eye.
- The doctor delivers laser pulses to make a small opening in the outer part of the iris, usually under the upper eyelid where it is hidden. Some people feel a brief sharp or pinching sensation with each pulse.
- The lens is removed and your eye pressure is checked again after a wait.
The opening gives the fluid a second route from behind the iris to the front, so that the iris is not pushed forward against the drainage angle.
Recovery
- Blurred vision, mild redness, a mild ache and sensitivity to light are common for a day or two.
- Anti-inflammatory drops are usually prescribed for a short course.
- Carry on with any glaucoma drops unless you are told otherwise.
- Most people return to ordinary activities the next day.
- A review visit is arranged to check the pressure and to confirm that the opening is working. The other eye is often treated on a separate day.
Risks and limits
- A rise in eye pressure. Usually temporary. It is checked for after the laser.
- A small bleed from the iris. This can blur vision for a short time and usually clears without treatment.
- Inflammation. Usually mild and treated with drops.
- Glare, a line of light or a ghost image. A small number of people notice this afterwards. It often becomes less noticeable with time.
- The opening can close. If it does, the laser may need to be repeated.
- Cataract may progress sooner. This has been reported in some eyes.
- The limits of the procedure: an iridotomy does not improve vision and does not cure glaucoma. In some eyes the angle stays narrow even with a working opening. Regular checks of pressure, the optic nerve and the visual field continue, and some people need drops or other treatment as well.
Preparing for either procedure
- Eat normally and take your usual medicines and eye drops unless told otherwise. No fasting is needed.
- Arrange for someone to take you home. Do not drive yourself.
- Bring your current glasses, your eye drops and your medicine list.
- Expect to be at the hospital for an hour or more, because of the drops beforehand and the pressure check afterwards.
- Before the procedure, the doctor explains what is planned and the risks, answers your questions and asks for your written consent.
After either procedure, call the same day if you have increasing pain, worsening vision, increasing redness, eye pain with headache or nausea, a sudden shower of floaters, flashes of light, or a curtain or shadow in the vision. During OPD hours, call 80966 65550. When the hospital is closed, go to the emergency department of a 24-hour hospital. More in after your eye surgery.
Frequently asked questions
Has my cataract come back?
No. A cataract cannot grow back, because the natural lens has been removed. What can happen is that the thin membrane holding the lens implant turns cloudy over months or years. This is called posterior capsule opacification, and YAG laser capsulotomy is the usual treatment for it.
Does YAG laser hurt?
The eye is numbed with drops. During a capsulotomy most people feel little or nothing and notice clicks and flashes of light. During an iridotomy, some people feel a brief sharp or pinching sensation with each laser pulse. Tell the doctor if you are uncomfortable.
How long does it take?
The laser itself usually takes a few minutes. With the drops beforehand and a pressure check afterwards, expect to be at the hospital for an hour or more.
Can I drive home afterwards?
No. Vision is blurred for a few hours from the drops, the contact lens gel and the bright light. Come with someone who can take you home.
Will I need the capsulotomy again?
Usually not. Once an opening has been made in the cloudy membrane, it generally stays open. Occasionally an opening needs to be enlarged.
Will a capsulotomy bring back the vision I had after cataract surgery?
It clears the blur caused by the cloudy membrane. If something else is also affecting the eye, such as a condition of the retina, the optic nerve or the cornea, that part will not change. This is why the eye is examined before laser is advised.
Does an iridotomy cure glaucoma?
No. An iridotomy changes the way fluid moves inside the eye and reduces the risk of a sudden angle-closure attack. Eye pressure, the optic nerve and the visual field still need regular checks, and some people still need drops or other treatment.
Are floaters after a capsulotomy normal?
Yes. Small floaters are common in the first days and usually become less noticeable over a few weeks. A sudden shower of floaters, flashes of light, or a curtain or shadow in the vision is different and needs an examination the same day.
Related pages
Appointments and contact
You can reach Dr. P. Siva Reddy Eye Hospital on WhatsApp or by phone during OPD hours.
OPD hours: Monday to Saturday, 10 AM to 2 PM and 4:30 PM to 7 PM. Closed on Sunday.