Closed-Angle Glaucoma: Symptoms, Causes & Treatment Options

Closed-angle Glaucoma is a serious but less common type of Glaucoma that can damage the optic nerve. It occurs due to a rapid increase in eye pressure and has two types: acute and chronic angle-closure Glaucoma.

Closed-angle Glaucoma accounts for about 10% of all Glaucoma cases and is responsible for nearly 50% of Glaucoma-related blindness worldwide. This condition requires immediate medical consultation to prevent permanent vision loss. 

In this article, we will help you understand the symptoms, causes, risk factors, diagnosis, treatment options, and preventive tips for Closed-angle Glaucoma. 

What is Closed-angle Glaucoma(CAG)

CAG is also known as angle-closure Glaucoma or narrow-angle Glaucoma. It is a condition in which the pressure inside the eye (intraocular pressure) increases rapidly due to blocked fluid drainage.

This fluid, known as aqueous humor, normally flows out of the eye through a drainage angle located where the cornea and iris meet. When this angle becomes narrow or blocked, the aqueous humor cannot drain properly, causing pressure to build up rapidly.

CAG symptoms

Closed-angle Glaucoma symptoms can vary depending on whether it is acute or chronic in nature.

Acute CAG symptoms

Acute CAG is characterized by sudden onset and severe symptoms. Here are the signs a person can notice in case of acute CAG:

• Severe headache
• Blurred vision
• Pain in the eyes
• Eye redness
• Nausea and vomiting
• Halos or rainbow-colored rings around light

Acute CAG type is considered a medical emergency, and it requires prompt medical help.

Chronic CAG symptoms

Chronic CAG develops slowly over time and may include:

• Gradual vision changes such as increasing blur or difficulty seeing in low light
• Mild eye discomfort or mild ache in the eyes
• Intermittent eye redness or mild irritation

Cause of CAG

In the case of acute CAG, the drainage angle in the eye suddenly becomes blocked, leading to increased pressure. In chronic CAG, the drainage angle in the eye is partially blocked at times. These blockages can cause scarring to develop over time. 

A study published by the National Library of Medicine in 2021 suggests that acute CAG can occur for different reasons, but not all of them are fully known. The primary cause appears to be the specific structure of the eye which increases the likelihood of this condition.

Here are some different anatomical and physiological factors that contribute to CAG: 

• Pupillary block: Iris bulging narrows the angle, blocking fluid drainage
• Irregularity at the level of the iris or ciliary body: Anomalies like thicker iris obstruct fluid outflow
• Irregularity at the level of lens: CAG patients often have a thicker lens, blocking fluid flow
• Irregularity posterior to the lens: In rare cases, aqueous humor movement issues increase eye pressure 

Risk factors of CAG

There are a few risk factors for CAG. It includes the following:

• Older age
• Female gender
• Being east Asian
• Farsightedness
• Anatomical features like a shallow anterior chamber or thicker lens
• Family history of CAG
• Health conditions such as Diabetes and Hypertension
• Certain medications that can trigger or worsen CAG

CAG diagnosis

The development can be detected with the onset of symptoms, and you can consult an eye care specialist for further diagnosis. An eye care specialist can investigate your eye condition in the following ways:

• Gonioscopy examination of your eye’s anterior (front) chamber
• Tonometry to measure changes in optic nerve 
• Pachymetry to check any change in the thickness of your cornea
• Slit-lamp examination for a complete examination of your anterior eye
• Perimetry to analyze your visual field
• Optical Coherence Tomography (OCT) to evaluate optic nerve head and anterior segment
• Retinal OCT

Also read: To know more about these tests in detail, you can read The Comprehensive Guide to the Glaucoma Test.

CAG treatments

CAG is an irreversible eye condition if not treated on time. But on diagnosing it in the early stages, a doctor can recommend the following treatment for Glaucoma:

Medical treatments

The medical treatment or medications include:

• Prostaglandins eye drops: These eye drops reduce eye pressure by increasing the outflow from the eyes. You can buy Careprost 3 ml. of 0.03% from WowRxPharmacy at affordable prices
• Carbonic anhydrase inhibitors: These are aqueous suppressants and reduce the amount of fluid produced in the eyes
• Rho kinase inhibitors: These medications are helpful in increasing the trabecular outflow obstructed due to anterior synechiae (adhesion within the eyes)

Laser treatment

Your doctor can also recommend a laser treatment depending on the progression of your Glaucoma. The laser treatment includes:

• Iridotomy
• Argon Laser Peripheral Iridoplasty
• Endocyclophotocoagulation
• Continuous Trans-scleral Cyclophotocoagulation

Surgical treatment

In case your Closed-angle Glaucoma progresses and the intraocular pressure cannot be controlled with the above-mentioned treatment, your doctor may suggest surgical treatment.

The surgical treatment includes:

• Lens extraction
• Surgical Iridectomy
• Trabeculectomy
• Glaucoma drainage device

Natural treatment

Natural approaches for Glaucoma include dietary changes, such as consuming antioxidant-rich foods and omega-3 fatty acids from fish, which support eye health. Herbal supplements like bilberry and ginkgo biloba may aid in eye circulation and pressure reduction but should be used cautiously under medical guidance. Eye exercises and stress-reduction techniques like yoga can improve blood flow and alleviate eye strain. 

Tips to prevent CAG

Preventing CAG primarily involves early detection and management of risk factors. Key preventive tips for Glaucoma include:

• Routine eye exams can detect early signs of Glaucoma before symptoms appear. Inform your eye doctor of any family history of Glaucoma, as genetics can play a role
• Manage health conditions like control diabetes and hypertension, as these conditions can increase the risk of Glaucoma
• Take breaks during prolonged near tasks and ensure adequate lighting to reduce eye strain
• Consume a healthy balanced diet that has antioxidants, exercise regularly, and manage stress levels
• If prescribed eye drops for elevated eye pressure, use them as directed by doctors or instructions given on the label 

Conclusion

Closed-angle Glaucoma is a type of Glaucoma that can cause permanent loss of vision. It comes with symptoms such as eye redness and pain, severe headache, nausea, and vomiting. The main cause of CAG is the rapid increase in intraocular pressure caused by an obstruction in the outflow of aqueous humor. Other factors like pupillary blockage, thicker iris, and aqueous misdirection can also lead to CAG. 

Diabetes, family history, farsightedness, and older age are a few risk factors of CAG. This condition can lead to vision loss if not treated on time. So, it is important to have regular eye exams and carefully monitor your symptoms. Seek a doctor’s help if you observe any signs of CAG. The doctor can examine your complete eye to investigate and analyze the visual field. After diagnosis, medications, laser, or surgical treatment can be recommended to avoid further progression of the eye condition. Simple lifestyle changes like regular exercise and eating a diet full of antioxidants can also reduce the risk of developing CAG.

Frequently Asked Questions

• medlineplus.gov
• kidshealth.org