What Is Angle-Closure Glaucoma?
Angle-closure glaucoma is an eye disorder in which the functioning of the optic nerve is impacted by intraocular pressure build-up, resulting in vision loss.
Angle-closure glaucoma, also called closed-angle glaucoma, is a rare ailment, accounting for about 20% of the total glaucoma cases globally. Contrary to open-angle glaucoma, closed-angle glaucoma develops suddenly; it is a serious condition that demands immediate medical treatment and care. If ignored, it can lead to permanent vision loss.
What Causes Angle-Closure Glaucoma?
The eye constantly creates a fluid, called the aqueous humour, to nourish the internal biological structure. This fluid goes out through a drainage angle. In a normal and healthy eye, this flow is smooth and unobstructed.
Angle-closure glaucoma occurs when the iris in the eye bulges or expands, either partially blocking or completely shutting off the drainage pathway. Subsequently, the intraocular pressure (IOP) rises, damaging the optic nerve and impacting its performance, eventually impairing normal vision.
Symptoms of Angle-Closure Glaucoma
Are you:
- Experiencing eye pain?
- Suffering from red eye?
- Having a sudden headache and dizziness?
- Finding it hard to focus because objects appear hazy?
- Having trouble reading printed literature or digital material?
If you have any of these warning signs, you are probably a victim of closed-angle glaucoma and must seek immediate medical help. If left untreated, vision loss can occur within hours – it is that bad, mind you.
Who Is at Higher Risk of Angle- Closure Glaucoma?
The following segments of citizens are at higher risk of angle-closure glaucoma:
- Eye Structure: Individuals with smaller eyes or naturally narrow drainage angles have a higher likelihood of being affected by angle-closure glaucoma
- Age and Family History: Persons who are over 40 and have close relatives with glaucoma are more susceptible
- Other Eye Conditions: Certain eye problems, including uveitis and cataracts, may alter the position of the iris or affect fluid drainage, potentially resulting in angle-closure glaucoma
- Pupil Enlargement: In susceptible individuals, pupil enlargement in low-light conditions or in response to stress may narrow the drainage angle and cause angle-closure glaucoma
- Individuals who suffer from hypertension and/or diabetes
- Individuals who suffer from farsightedness
- People of African-Caribbean and East Asian origin
How Is Angle-Closure Glaucoma Diagnosed?
The following diagnostic tests and processes are used to detect angle-closure glaucoma:
Gonioscopy: It is a non-invasive test in which an eye care specialist uses a special lens and a light source to check the eye’s drainage angle (anterior chamber angle) and get a quick, 360-degree assessment of the angle width.
Tonometry: It is a rapid and painless test that measures pressure inside your eye (IOP) to detect angle-closure glaucoma. Depending on how the test is performed, there are different variations of tonometry, viz. applanation tonometry, continuous monitoring tonometry, dynamic contour tonometry, rebound tonometry, etc.
Slit-Lamp Examination: It checks the depth of the anterior chamber and finds physical signs of iris crowding or fluid blockage.
Anterior Segment Optical Coherence Tomography (AS-OCT): It is a non-contact, high-resolution imaging technique that uses infrared light to measure anterior chamber depth, volume, and angle metrics.
Treatment for Angle-Closure Glaucoma
The treatment for angle-closure glaucoma depends on its type – whether it is acute angle-closure glaucoma or chronic angle-closure glaucoma.
Characterised by eye pain, red eye, and nausea, acute angle-closure glaucoma is a sudden and severe condition that calls for immediate medical treatment. These include:
Medications: The first-line treatment for angle-closure glaucoma includes administering topical eye drops, oral or intravenous medications, and topical steroids.
Your eye specialist will step up the treatment with a procedure called Laser Peripheral Iridotomy (LPI), in which a specialised laser makes a small hole in the iris, making way for fluid to flow freely and relieving the pressure block.
In case of chronic angle-closure glaucoma, the treatment includes long-term prescription eye drops, LPI, and cataract surgery.
In complex cases where medications and laser treatment do not yield results, doctors resort to high-end remedial procedures such as trabeculectomy or goniosynechialysis.
When Should You See an Eye Specialist?
Don’t hesitate to visit an eye care specialist if you notice a sudden, dramatic change in your vision or experience any of the symptoms of acute angle-closure glaucoma, including red eye, eye pain, headache, and nausea.
FAQ
Is angle-closure glaucoma an emergency?
Yes, indeed. If neglected, it can lead to irreversible damage.
Can angle-closure glaucoma cause permanent vision loss?
Yes. If not treated as a priority, it can cause permanent vision loss within a matter of hours.
What is the main treatment for angle-closure glaucoma?
Laser Peripheral Iridotomy (LPI) is the main treatment for angle-closure glaucoma.
Can angle-closure glaucoma be detected early?
Yes, it can be detected early through a comprehensive eye examination.
Is angle-closure glaucoma the same as open-angle glaucoma?
No, both are distinct eye disorders.
Dr Ashwini Karanjgaokar is a Consultant Ophthalmologist and Vitreo-Retinal Surgeon with over 30 years of experience. She specialises in retinal diseases, diabetic eye care, pediatric ophthalmology, and myopia management, and currently serves as a Visiting Vitreo-Retinal Consultant at Nanavati Max Super Speciality Hospital. Through her articles, she provides evidence-based guidance on eye health and vision care.
