Glaucoma and related conditions
Signs, diagnosis and treatment for each type of glaucoma, and the findings that come before it.
Written by Dr. M. Ali Tawfik Alyouzbaki, MD, OphthalmologistLast updated Sources citedEditorial policy
How a glaucoma evaluation unfolds
Glaucoma is a disease of the optic nerve. Pressure is the main risk factor that can be treated, but the diagnosis comes from the nerve and the field.[2]
- HistoryFamily, medicines, steroids, past eye injury
- PressureTonometry and corneal thickness
- AngleGonioscopy
- NerveDilated exam and OCT
- FieldVisual field testing
- PlanDiagnosis, risk and target
Condition guides
Select a condition to open it.
The most common type in the United States. The drain looks open, but fluid leaves the eye too slowly.[2]
Signs
- Usually no symptoms early
- Slow loss of side vision, often unnoticed
- Late: tunnel vision
Diagnosis
- Pressure, corneal thickness and gonioscopy (angle open)
- Optic nerve exam and OCT
- Visual fields, repeated over time
Treatment
- SLT laser or drops first
- More medicines, MIGS, or surgery if needed
- Regular monitoring for life
High pressure without damage. In the Ocular Hypertension Treatment Study, 9.5% of untreated people developed glaucoma in five years, compared with 4.4% of treated people.[3]
Signs
- No symptoms
- Pressure above the usual range
- Healthy optic nerve and normal visual field
Diagnosis
- Repeat pressure readings
- Corneal thickness
- Baseline OCT and visual field
Treatment
- Treatment if risk is higher
- Watchful monitoring if risk is lower
- Decision shared with you
A label for people with one or more signs that could mean glaucoma, but no definite damage yet.[4]
Signs
- No symptoms
- A nerve that looks suspicious, high pressure, or a borderline test
- Often found at a routine exam
Diagnosis
- Baseline photos and OCT
- Visual fields
- Gonioscopy and corneal thickness
Treatment
- Monitoring to see if anything changes
- Treatment if risk is high or change appears
- Follow-up timed to your risk
Nerve damage with normal pressure. In a long-term trial, lowering pressure by 30% cut progression from 35% to 12% of eyes.[5]
Signs
- No symptoms early
- Field loss can sit closer to center
- Pressure in the normal range
Diagnosis
- Careful nerve and field review
- Check for other causes of nerve damage
- Blood pressure and sleep history
Treatment
- Lowering pressure by about 30% from baseline
- Drops, laser or surgery
- Close field monitoring
The iris sits close to the drain and can block it. Ranges from a narrow angle with healthy nerves to angle-closure glaucoma with damage.[6]
Signs
- Often no symptoms
- Sometimes brief blur, halos or brow ache, often in dim light
- More common in farsighted eyes
Diagnosis
- Dark-room gonioscopy
- Anterior segment OCT or ultrasound
- Pressure, nerve and field checks
Treatment
- Laser iridotomy
- Lens extraction, especially with high pressure
- Drops or surgery if pressure stays high
An emergency. The drain closes suddenly and pressure rises quickly. Go to an emergency department right away.[6]
Signs
- Sudden severe eye pain and redness
- Blurred vision, halos around lights
- Headache, nausea or vomiting
Diagnosis
- Emergency pressure check
- Gonioscopy once the cornea clears
- Check of the other eye
Treatment
- Emergency department now
- Medicines to lower pressure fast
- Laser iridotomy, and often laser for the other eye
Pigment granules rub off the back of the iris and clog the drainage system.[7]
Signs
- Usually no symptoms
- Sometimes blur after exercise
- Often younger, nearsighted adults
Diagnosis
- Exam of the iris and drainage angle
- Pressure, OCT and fields
Treatment
- Drops or SLT laser
- Surgery if needed
Flaky material from the lens builds up in the drain. Known for higher peaks and swings in pressure than other types.[7]
Signs
- Usually no symptoms
- Pressure that swings and spikes
Diagnosis
- Flaky material seen on the lens
- Pressure, OCT and fields
- Care planning before cataract surgery
Treatment
- Drops or SLT laser
- Surgery if needed
- Closer follow-up
Abnormal new blood vessels grow over the drain, usually because the retina isn't getting enough blood.[7]
Signs
- Painful red eye
- Blurred vision
- Often with diabetes or a retinal vein blockage
Diagnosis
- Exam of the iris and angle for new vessels
- Retina exam and imaging
Treatment
- Treat the retina cause, often with a retina specialist
- Pressure-lowering drops
- Tube shunt surgery in many cases
Inflammation inside the eye, or steroid medicines in any form, can raise eye pressure.[7]
Signs
- Red, light-sensitive eye with inflammation
- Or no symptoms with steroid use
Diagnosis
- Pressure checks during steroid treatment
- Exam for inflammation
Treatment
- Control inflammation
- Adjust steroids when possible
- Drops, laser or surgery
A blow to the eye can damage the drainage angle and raise pressure, sometimes years later.[7]
Signs
- May appear soon after an injury, or years later
- Often one eye only
Diagnosis
- Gonioscopy for angle damage
- Lifelong pressure checks after a serious eye injury
Treatment
- Drops
- Surgery if needed
This is general information and doesn't replace an exam.
Types at a glance
| Type | Drainage angle | Pressure | Speed | Usual first step |
|---|---|---|---|---|
| Primary open-angle | Open | High or normal | Slow, painless | SLT or drops |
| Normal-tension | Open | Normal | Slow, painless | Lower pressure ~30% |
| Angle-closure (chronic) | Narrow or closed | Often high | Slow, often painless | Iridotomy or lens surgery |
| Acute angle-closure | Closed suddenly | Very high | Hours; painful | Emergency care |
| Secondary (pigment, exfoliation, neovascular, uveitic, traumatic) | Varies | Often high | Varies | Treat the cause and the pressure |
Who should be checked
Get checked if you're at higher risk
Glaucoma risk rises with age, and is higher for Black and Hispanic/Latino adults over 40 and for anyone with a close relative who has it.[1] People with diabetes are also at higher risk.[8] A comprehensive dilated eye exam, including a check of side vision, is how glaucoma is found.[1] Ask your eye doctor how often you should be examined.
Sources and references
- National Eye Institute. Glaucoma. National Institutes of Health. View source (opens in a new tab)
- Gedde SJ, Bowden EC, Challa P, et al; American Academy of Ophthalmology Preferred Practice Pattern Glaucoma Committee. Primary Open-Angle Glaucoma Preferred Practice Pattern. Ophthalmology. 2026;133(4):P1-P103. doi:10.1016/j.ophtha.2025.12.029 View source (opens in a new tab)
- Kass MA, Heuer DK, Higginbotham EJ, et al. The Ocular Hypertension Treatment Study: a randomized trial determines that topical ocular hypotensive medication delays or prevents the onset of primary open-angle glaucoma. Arch Ophthalmol. 2002;120(6):701-713. View source (opens in a new tab)
- Gedde SJ, Lind JT, Wright MM, et al; American Academy of Ophthalmology Preferred Practice Pattern Glaucoma Panel. Primary Open-Angle Glaucoma Suspect Preferred Practice Pattern. Ophthalmology. 2021;128(1):P151-P192. doi:10.1016/j.ophtha.2020.10.023 View source (opens in a new tab)
- Collaborative Normal-Tension Glaucoma Study Group. Comparison of glaucomatous progression between untreated patients with normal-tension glaucoma and patients with therapeutically reduced intraocular pressures. Am J Ophthalmol. 1998;126(4):487-497. View source (opens in a new tab)
- Gedde SJ, Chopra V, Vinod K, et al; American Academy of Ophthalmology Preferred Practice Pattern Glaucoma Committee. Primary Angle-Closure Disease Preferred Practice Pattern. Ophthalmology. 2026;133(4):P153-P201. doi:10.1016/j.ophtha.2025.12.030 View source (opens in a new tab)
- Glaucoma Research Foundation. Types of glaucoma. View source (opens in a new tab)
- Centers for Disease Control and Prevention. Announcement: Glaucoma Awareness Month, January 2016. MMWR Morb Mortal Wkly Rep. 2016;65(1):12. View source (opens in a new tab)
Book a glaucoma visit
Send a request and the office will contact you to set a time. You can also email [email protected].