Narrow angles and angle-closure glaucoma in San Antonio
Finding narrow angles early, and preventing an emergency with a quick in-office laser
Narrow angles are an anatomical condition in which the drainage space inside the eye is too narrow. Most people have no symptoms, but in some eyes the angle can close, causing a sudden, painful rise in eye pressure (acute angle closure, a medical emergency) or slow, silent damage to the optic nerve (chronic angle-closure glaucoma). The good news is that narrow angles can be found with a simple exam, and a quick in-office laser treatment called laser iridotomy often prevents the problem. At San Antonio Eye & Face Institute, Dr. Relief Jones, III, a glaucoma fellowship-trained ophthalmologist, performs laser iridotomy, and he and Dr. Maria Isabel Triana can check your angles at your next exam.
Reviewed by Dr. Relief Jones, III, M.D. · Last updated: October 9, 2026
Emergency warning signs. Sudden severe eye pain, a red eye, headache, nausea or vomiting, blurred vision, or halos around lights can mean an acute angle-closure attack. Get help immediately. Call us at (210) 485-1488 during business hours, and after hours go to an emergency room right away. Don’t wait for it to pass.
At a glance
| What it is | A drainage angle inside the eye that is too narrow and may close |
| Symptoms | Usually none. An acute attack causes severe eye pain, redness, headache, nausea, blurred vision, and halos |
| Key test | Gonioscopy, a close look at the drainage angle with a mirrored lens |
| Main treatment | YAG laser iridotomy: a quick, typically painless, in-office laser |
| Performed by | Dr. Relief Jones, III, M.D. – Fridays for narrow angles | Immediately for acute angle closure |
| Other treatments | Pressure-lowering drops, and lens removal (cataract or clear lens surgery) when appropriate |
| Insurance | Medicare and most plans cover medically necessary testing and treatment – See insurance we accept |
What are narrow angles?
Fluid (aqueous humor) is constantly made inside the eye and drains out through a small channel at the angle where the iris (the colored part of the eye) meets the cornea (the clear front surface). The channel’s filter is the trabecular meshwork, which leads to Schlemm’s canal. When this angle is too narrow, the iris can block the drain, and fluid can’t leave the eye normally.
Eye doctors describe a spectrum:
- Narrow angles (angle-closure suspect). The angle is narrow and could close, but hasn’t.
- Primary angle closure. The angle has closed or partly closed, with adhesions or higher pressure, but the optic nerve isn’t damaged.
- Primary angle-closure glaucoma. The angle has closed and the optic nerve has been damaged.
When an angle closes suddenly, the pressure inside the eye can spike, which can damage the optic nerve quickly and cause permanent vision loss. This is acute angle closure. When it closes slowly over time, the damage can build quietly. This is chronic angle-closure glaucoma.
Narrow-angle vs. open-angle glaucoma
| Narrow angle / angle-closure | Open-angle | |
|---|---|---|
| What’s happening | The drainage angle is physically narrowed or closed | The angle looks open, but fluid doesn’t drain well |
| How common | Less common in the U.S. | The most common type |
| How it develops | Can be sudden (acute) or gradual | Usually slow, over many years |
| Main treatment | Laser iridotomy to open the angle | Drops, SLT laser, or surgery |
| Symptoms | Usually none until the angle closes | Usually none until late |
How common are narrow angles?
Angle-closure glaucoma is a leading cause of irreversible blindness worldwide, affecting an estimated 20 million people, with projections of about 32 million by 2040. In the United States it’s less common than open-angle glaucoma, but risk varies a lot by group.
Who is at risk?
- Age. Risk rises after age 40. As we age, the natural lens grows thicker and moves forward, which narrows the angle.
- Women. Women are more likely to be affected, accounting for roughly 70% of cases.
- Asian ancestry. People of Chinese, Vietnamese, or Indian heritage are about 2 to 4 times more likely to have narrow-angle problems, partly because their eyes tend to be smaller with shallower front chambers.
- Inuit and Alaska Native people also have a higher risk.
- Family history. Having a close relative with angle-closure glaucoma raises your risk several times over, and genes such as PLEKHA7 and COL11A1 have been linked to it.
- Farsightedness (hyperopia). Farsighted eyes tend to be smaller with shallower front chambers.
- Rare eye conditions such as nanophthalmos (abnormally small eyes).
Medications that can trigger angle closure
In people with narrow angles, some medications can trigger an attack. According to the American Academy of Ophthalmology, these include medicines that dilate the pupil, such as some antihistamines, antidepressants, and anti-anxiety drugs, and some over-the-counter cold and allergy remedies. If a label says “do not use if you have glaucoma,” it’s usually referring to narrow-angle glaucoma. Topiramate (used for migraines and seizures) and sulfa-based drugs have also been linked to angle closure, through a different mechanism. Two of Dr. Jones’s mentors at Harvard Medical School were among the first to recognize the connection with topiramate.
Always ask your ophthalmologist if you’re concerned about your medications, and don’t stop a prescribed medicine on your own. After a successful iridotomy, the risk from many of these medications is generally much lower, but ask us first.
Symptoms
Narrow angles usually have no symptoms. They’re typically found during a routine eye exam. Some people have occasional mild episodes (blurry vision or halos in dim light, sometimes with a headache) that go away on their own, and these can be warning signs.
An acute angle-closure attack can cause:
- Sudden, severe eye pain
- A red eye
- Headache, often around the eye or on the same side of the head
- Nausea and vomiting (which can be mistaken for a migraine or a stomach problem)
- Blurred vision
- Halos or rainbow-colored rings around lights
This is a medical emergency. Don’t wait for it to pass. Call us right away, or go to an emergency room after hours.
How narrow angles are diagnosed
- A complete eye exam. Your ophthalmologist checks your vision, eye pressure, and optic nerve. If your angles may be narrow, they check your angle before dilating your eyes, because dilating drops can rarely trigger an attack in very narrow angles.
- Eye pressure measurement (tonometry). Most people with narrow angles have normal pressures when they’re found.
- Gonioscopy. The most important test. After numbing drops, your ophthalmologist places a special mirrored lens on your eye to look directly at the drainage angle and see how open or closed it is, and whether any adhesions (peripheral anterior synechiae) have formed. This tells us whether you’re at risk of an attack.
- Imaging, if needed (rare).
Do you need treatment?
Not every narrow angle needs treatment. Dr. Jones or Dr. Triana decides based on how narrow your angle is, whether it has started to close, your eye pressure, the health of your optic nerve, your symptoms, and your risk factors. If you’ve been told you have narrow angles and aren’t sure about the recommendation, a second opinion is a reasonable step.
Treatment options
Laser iridotomy (the main treatment)
YAG laser iridotomy is a quick, in-office procedure in which a laser makes a tiny hole in the peripheral iris. The hole lets fluid flow between the back and front of the eye, so the iris can lie flat and away from the drainage angle. In eyes with narrow angles that haven’t closed, it’s used to prevent an attack. If the angle has closed and the pressure has risen, it helps open the angle and lower the pressure. It’s typically painless and takes just a few minutes, and most people can return to normal activities quickly.
What to expect. Our technician checks your eye pressure and places drops to make the pupil smaller and a pressure reduction drop. Before the procedure, Dr. Jones will place numbing drops. He will then place a special contact lens on the eye and applies the laser. Afterwards, you will receive an anti-inflammatory drop and another pressure reduction drop. Your pressure will be checked after a short wait. You will be schedule for a treatment of the other eye 1-2 weeks later. A follow-up exam will be scheduled 1-2 weeks later. Dr. Jones performs this procedure for patients on Friday mornings or immediately for acute angle closure glaucoma.
Risks. Laser iridotomy is generally safe. Possible effects include a temporary rise in eye pressure, mild inflammation, short-term blurry vision, glare or lines in your vision, minor bleeding, and, rarely, a hole that closes and needs retreatment. Your doctor will review these with you.
After iridotomy, you still need regular eye exams. Iridotomy prevents or relieves angle closure, but it doesn’t repair damage that has already happened, and some patients also need drops or other treatment.
Pressure-lowering drops
Drops such as pilocarpine, which constricts the pupil, can temporarily pull the iris away from the drain and lower pressure. They’re not a long-term treatment. They’re used for short-term control and to prepare the eye for definitive treatment.
Lens removal (cataract or clear lens surgery)
Because a thickening lens is a major cause of narrow angles, removing it can deepen the front of the eye and open the angle. For some patients, especially those with angle-closure glaucoma, lens removal (cataract surgery, or clear lens extraction in patients without a cataract) can be recommended in addition to or instead of laser iridotomy. Dr. Jones will advise you on the best approach. Learn about cataract surgery
Narrow angles and cataracts
Cataracts make the lens thicker, which narrows the angle further. That’s one reason narrow angles become more common with age, and one reason cataract surgery can help. If you have narrow angles and cataracts, we’ll coordinate the two. Dr. Jones is fellowship-trained in glaucoma and performs all of our cataract surgery. Cataract surgery · Laser cataract surgery
What helps (and what doesn’t)
- Regular eye exams, especially if you’re over 40 or in a higher-risk group.
- Treatment when it’s recommended. Preventive laser iridotomy is the best defense.
- Checking your medications with your ophthalmologist.
- Knowing the warning signs, and getting immediate help if they occur.
- Lifestyle changes don’t treat narrow angles. Staying hydrated and managing stress are good for your health, but they don’t open a narrow angle. Don’t rely on them in place of an exam or treatment.
Why choose San Antonio Eye & Face Institute
- Glaucoma fellowship-trained. Dr. Jones completed a clinical glaucoma fellowship at Massachusetts Eye and Ear/Harvard Medical School, and Dr. Triana completed a glaucoma genetics research fellowship there. Read more about our glaucoma care
- In-office laser iridotomy, with no operating room needed.
- One team for narrow angles, glaucoma, and cataracts.
- Physician-owned, so you see your doctors from your first exam to your last follow-up.
- Se habla español.
Request an Eye Exam
Call (210) 485-1488
Frequently asked questions
What are narrow angles? Narrow angles are an anatomical condition in which the space between the iris (the colored part of the eye) and the cornea (the clear front surface) is too narrow. This is where fluid drains out of the eye, so a narrow angle can block drainage and, in some eyes, close completely.
Do narrow angles cause symptoms? Usually not. Narrow angles are almost always found during a routine eye exam, which is why regular exams are so important. Symptoms typically appear only if the angle begins to close.
What is angle-closure glaucoma? Angle-closure glaucoma occurs when the drainage angle closes, blocking fluid from leaving the eye. Pressure inside the eye can rise suddenly (acute) or gradually (chronic), damaging the optic nerve and causing permanent vision loss.
What are the symptoms of an acute angle-closure attack? Sudden severe eye pain, a red eye, headache, nausea or vomiting, blurred vision, and halos or rainbow-colored rings around lights. An acute attack is a medical emergency.
What should I do if I think I am having an angle-closure attack? Get help immediately. Call our office during business hours, and if it is after hours, go to an emergency room right away. Do not wait for symptoms to pass, because prompt treatment is needed to prevent permanent vision loss.
Who is at risk for narrow angles? Risk is higher in people over 40, women, people of Asian descent, Inuit people, people with a family history of angle-closure glaucoma, and people who are farsighted, because farsighted eyes tend to be smaller with shallower front chambers.
How are narrow angles diagnosed? The key test is gonioscopy, in which your ophthalmologist places a special mirrored lens on your numbed eye to look directly at the drainage angle. We also check your eye pressure and your optic nerve.
Does everyone with narrow angles need treatment? Not necessarily. Whether you need treatment depends on how narrow your angle is, whether it has begun to close, your eye pressure, the health of your optic nerve, your symptoms, and your risk. Dr. Jones or Dr. Triana will explain the best plan for your eyes.
What is laser iridotomy? Laser iridotomy is a quick in-office procedure in which a laser makes a tiny hole in the edge of the iris. The hole lets fluid flow between the back and front of the eye, so the iris can fall back from the drainage angle, which prevents or relieves angle closure.
Is laser iridotomy painful? The procedure is typically painless and takes just a few minutes. Numbing drops are used, and most people return to normal activities quickly.
What are the risks of laser iridotomy? Laser iridotomy is generally safe. Possible effects include a temporary rise in eye pressure, mild inflammation, blurry vision for a short time, glare or lines in the vision, minor bleeding, and, rarely, a hole that closes and needs retreatment. Your doctor will review the risks with you.
Will I still need glaucoma drops after iridotomy? Sometimes. Iridotomy prevents or relieves angle closure, but it does not repair damage that has already happened. If your pressure is still high or you have glaucoma, you may need drops or other treatment, and you will still need regular exams.
Can cataract surgery help narrow angles? Yes. As we age, the natural lens thickens and pushes forward, which can narrow the angle. Removing the lens during cataract surgery, or clear lens extraction, deepens the front of the eye and can open the angle. Whether it is recommended in addition to or instead of laser iridotomy depends on your eyes, and Dr. Jones will advise you.
Can medications trigger angle closure? Yes, in people with narrow angles. Some antihistamines, antidepressants, anti-anxiety medications, and over-the-counter cold and allergy medicines can dilate the pupil and may trigger an attack, and topiramate and sulfa-based drugs have also been linked to angle closure. Ask your ophthalmologist about your medications, and read labels that warn against use if you have glaucoma.
Can I have my eyes dilated if I have narrow angles? Dilating drops can rarely trigger an attack in eyes with very narrow angles, which is why your ophthalmologist checks your drainage angle before dilating. If you have been told you have narrow angles, tell any eye doctor before they dilate your eyes.
Do you perform laser iridotomy in San Antonio? Yes. Dr. Relief Jones, III performs YAG laser iridotomy in our office.
This page is for general education and isn’t a substitute for an eye exam. Only an eye doctor can tell you whether you have narrow angles and recommend treatment.