Angle-Closure Glaucoma

Glaucoma is a group of eye conditions that can cause blindness by damaging the optic nerve. One of its most severe forms is angle closure glaucoma. This type of glaucoma is a medical emergency that requires prompt diagnosis and treatment to prevent permanent vision loss. Let us look into the symptoms, causes, risk factors, diagnosis, and treatment options for angle closure glaucoma.

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What is Angle Closure Glaucoma?

Angle-closure glaucoma, also known as acute glaucoma or narrow-angle glaucoma, occurs when the drainage angle of the eye becomes blocked. This blockage prevents the aqueous humour, the fluid inside the eye, from draining properly, leading to a rapid increase in intraocular pressure (IOP). The sudden spike in IOP can cause severe pain and vision loss.

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Symptoms of Angle Closure Glaucoma

Recognizing the symptoms of angle closure glaucoma is crucial for seeking timely medical intervention. Common symptoms include:

It’s important to note that these symptoms can come on suddenly and escalate quickly, making angle closure glaucoma a true ocular emergency.

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Causes of Angle Closure Glaucoma

Understanding the underlying causes of angle closure glaucoma can aid in its prevention and management. The primary cause of angle closure glaucoma is a blockage in the drainage angle of the eye. This blockage can be due to several factors:

Anatomical Factors

Individuals with smaller eyes or specific anatomical features, such as a narrow drainage angle or a shallow anterior chamber, are at higher risk. These anatomical traits can impede the normal flow of aqueous humour, leading to angle closure.

Pupil Dilation

Dilation of the pupil, whether due to low light conditions or certain medications, can exacerbate the risk. When the pupil dilates, it can push the iris forward, further narrowing the drainage angle and potentially causing a blockage.

Hyperopia

Farsighted individuals, or those with hyperopia, have an increased risk of developing angle closure glaucoma. This is because their eyes tend to be smaller, increasing the likelihood of a narrow drainage angle.

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Risk Factors for Angle Closure Glaucoma

Several risk factors can increase the likelihood of developing angle closure glaucoma. Being aware of these risk factors can help in early detection and preventive measures.

Age

The risk of angle closure glaucoma increases with age, particularly in individuals over the age of 40.

Gender

Women are more likely to develop angle-closure glaucoma compared to men due to anatomical differences in the structure of the eye.

Ethnicity

Certain ethnic groups, such as people of East Asian descent, have a higher prevalence of angle closure glaucoma due to genetic predispositions and anatomical differences.

Family History

A family history of angle closure glaucoma can significantly increase the risk, suggesting a genetic component to the condition.

Medications

Certain medications, such as anticholinergics and adrenergic agents, can increase the risk of angle closure glaucoma by causing pupil dilation.

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Diagnosis of Angle Closure Glaucoma

Accurate and timely diagnosis is essential for managing angle closure glaucoma effectively. Several diagnostic tools and tests are used to confirm the condition:

Gonioscopy

Gonioscopy is a specialized eye examination that allows the ophthalmologist to visualize the drainage angle of the eye. This test is crucial for identifying any blockages or abnormalities in the drainage angle.

Tonometry

Tonometry measures the intraocular pressure (IOP) of the eye. Elevated IOP is a crucial indicator of angle closure glaucoma.

Optical Coherence Tomography (OCT)

OCT is a noninvasive imaging test that provides detailed cross-sectional images of the eye’s structures, including the drainage angle. This test helps assess the severity of the condition.

Ultrasound Biomicroscopy

Ultrasound biomicroscopy uses high-frequency sound waves to create detailed images of the eye’s anterior segment. This test is instrumental in assessing anatomical features that may contribute to angle closure.

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Treatment Options for Angle Closure Glaucoma

Prompt treatment is critical to prevent permanent vision loss caused by angle closure glaucoma. Treatment options vary depending on the severity of the condition and may include both medical and surgical interventions.

Medications

Initially, medications such as topical eye drops and oral medications are used to lower intraocular pressure (IOP) and alleviate symptoms. These medications may include:

Laser Peripheral Iridotomy

Laser peripheral iridotomy is a standard procedure used to treat angle closure glaucoma. In this procedure, a laser is used to create a small hole in the peripheral iris, allowing aqueous humour to bypass the blockage and flow more freely.

Surgical Iridectomy

In cases where laser peripheral iridotomy is not practical or feasible, a surgical iridectomy may be performed. This procedure involves surgically removing a portion of the iris to create an alternative pathway for fluid drainage.

Cataract Surgery

Cataract surgery can also be an effective treatment for angle closure glaucoma, particularly in individuals with coexisting cataracts. By removing the cataract and replacing the natural lens with an artificial one, the anterior chamber depth is increased, reducing the risk of angle closure.

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Management and Prevention of Angle Closure Glaucoma

Long-term management and preventive measures are essential for individuals at risk of angle closure glaucoma. Regular eye examinations and monitoring are crucial for early detection and intervention.

Regular Eye Exams

Routine eye exams, particularly for individuals over the age of 40 or those with risk factors, can help in the early detection and management of angle closure glaucoma.

Medication Management

For individuals on medications that may increase the risk of angle closure glaucoma, consultation with an ophthalmologist is essential to evaluate the risk and adjust medications if necessary.

Lifestyle Modifications

Certain lifestyle modifications, such as avoiding low-light environments and being cautious with over-the-counter medications that may cause pupil dilation, can help reduce the risk of angle closure glaucoma.

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Conclusion

Angle-closure glaucoma is a serious and potentially blinding condition that requires prompt diagnosis and treatment. By understanding the symptoms, causes, risk factors, and treatment options, individuals at risk can take proactive steps to manage and prevent this condition. Regular eye exams and consultations with an ophthalmologist are essential for maintaining eye health and preventing vision loss due to angle closure glaucoma.