interval angle-closure glaucoma

Interval angle-closure glaucoma is a type of primary glaucoma characterized by the sudden closure of the anterior chamber angle, leading to elevated intraocular pressure (IOP). This condition can cause symptoms such as sudden pain, redness, headache, and blurry vision with haloes around lights that resolves spontaneously.

The symptoms of interval angle-closure glaucoma are similar to those of acute angle-closure glaucoma, but they resolve on their own without any treatment. However, if the condition is not properly managed, it can lead to permanent vision damage.

Interval angle-closure glaucoma is often associated with a shallower anterior chamber and a more pronounced iris curvature, which can cause the iris to block the drainage of aqueous humor and lead to increased IOP.

Symptoms of interval angle-closure glaucoma include:

• Sudden pain
• Redness
• Headache
• Blurry vision with haloes around lights that resolves spontaneously

It's essential to note that interval angle-closure glaucoma can be a precursor to more severe forms of glaucoma, such as acute angle-closure glaucoma. Therefore, it's crucial to seek medical attention if you experience any symptoms related to this condition.

References:

• [3] Interval angle-closure glaucoma has_symptom sudden pain, redness, headache, and blurry vision with haloes around lights that resolves spontaneously.
• [6] Intermittent angle-closure indicates there is an obstruction to the aqueous outflow mechanism in the anterior chamber.

Interval angle-closure glaucoma, also known as intermittent or periodic angle-closure glaucoma, is a condition where the drainage system in the eye becomes intermittently blocked, leading to increased pressure and potential damage to the optic nerve.

Common signs and symptoms of interval angle-closure glaucoma:

• Intermittent vision changes: Blurred vision, double vision, or loss of peripheral vision may occur periodically.
• Eye pain: Mild to moderate eye pain or discomfort may be experienced during episodes.
• Rainbow haloes around lights: Seeing colorful haloes or rings around lights, especially at night, can indicate increased pressure in the eye.
• Nausea and vomiting: Some people may experience nausea or vomiting during episodes of angle-closure glaucoma.
• Redness and swelling: The affected eye may appear red, swollen, or inflamed during episodes.

Important notes:

• Interval angle-closure glaucoma can be a precursor to acute angle-closure glaucoma, which is a medical emergency. If you experience sudden and severe symptoms, seek immediate medical attention.
• Regular eye exams are crucial for detecting interval angle-closure glaucoma early on, especially if you're at high risk.

References:

• [10] Primary angle-closure glaucoma. Acute angle-closure glaucoma comes on quickly and is a medical emergency because permanent vision damage can happen very quickly.
• [13] Symptoms of angle-closure glaucoma may include headaches, eye pain, nausea, rainbows around lights at night, and very blurred vision.

Please note that these symptoms may not be present all the time, but rather during episodes or periods when the drainage system is intermittently blocked. If you're experiencing any of these symptoms, it's essential to consult with an eye care professional for proper evaluation and treatment.

Diagnostic Tests for Interval Angle-Closure Glaucoma

Interval angle-closure glaucoma, also known as chronic or intermittent angle closure, is a type of glaucoma where the drainage channels in the eye are intermittently blocked. Diagnosing this condition requires a combination of clinical evaluation and diagnostic tests.

• Gonioscopy: This is considered the gold standard test for diagnosing angle-closure glaucoma, including interval forms (3). Gonioscopy allows for a detailed examination of the anterior chamber angle, where the cornea meets the iris. A trained ophthalmologist can use gonioscopy to assess the angle's configuration and identify any signs of closure.
• Tonometry: This test measures the pressure inside the eye, which is often elevated in glaucoma patients (9). Tonometry can help confirm a diagnosis of interval angle-closure glaucoma by demonstrating consistently high intraocular pressures.
• Ophthalmoscopy: During this test, an ophthalmologist examines the optic nerve and retina using a special microscope. This can help identify any signs of glaucomatous damage (8).
• Perimetry Test: This visual field test assesses a patient's ability to see objects in their peripheral vision. Interval angle-closure glaucoma may cause subtle changes in visual field, which perimetry can detect.
• Pachymetry Test: This test measures the thickness of the cornea, which is often thinner in patients with interval angle-closure glaucoma (14).

Other Diagnostic Considerations

In addition to these tests, a comprehensive eye examination should also include:

• A thorough medical history and review of symptoms
• Slit-lamp examination to assess the anterior segment and identify any signs of angle closure
• Fundus examination to evaluate the retina and optic nerve

Early detection and diagnosis are crucial for effective management and treatment of interval angle-closure glaucoma.

References: (3) I Riva · 2020 · Cited by 70 — (9) Dec 27, 2022 — (14) Apr 15, 2016 —

Interval angle-closure glaucoma, also known as intermittent or chronic angle-closure glaucoma, requires prompt medical attention to prevent permanent vision damage.

Initial Medical Treatment

The initial treatment for interval angle-closure glaucoma typically involves the use of topical glaucoma medications that are not contraindicated in the patient [6]. These medications can help lower intraocular pressure (IOP) and alleviate symptoms. In some cases, intravenous medications may also be used to manage IOP.

Medications Used

The following medications are commonly used to treat interval angle-closure glaucoma:

• Beta-blockers (e.g., timolol)
• Prostaglandin analogs (e.g., latanoprost)
• Alpha agonists (e.g., brimonidine)
• Carbonic anhydrase inhibitors (e.g., acetazolamide)

These medications can be used alone or in combination to manage IOP and alleviate symptoms [6].

Importance of Prompt Treatment

It is essential to note that interval angle-closure glaucoma requires prompt medical attention to prevent permanent vision damage. Delayed treatment can lead to irreversible optic neuropathy and vision loss.

References

• [6] Initial medical treatment typically involves all topical glaucoma medications that are not contra-indicated in the patient, together with intravenous ...
• [12] Glaucoma, characterized by increased intraocular pressures (IOP), can result in optic neuropathy and vision loss if left untreated.[1]

Interval Angle-Closure Glaucoma Differential Diagnosis

Interval angle-closure glaucoma (IACG) is a type of glaucoma that can be challenging to diagnose due to its intermittent nature. The differential diagnosis for IACG involves considering various conditions that may present with similar symptoms.

• Open-Angle Glaucoma: This is the most common form of glaucoma and can be differentiated from IACG by the presence of a normal or slightly shallow anterior chamber, as well as a lack of symptoms during the interval periods. [1]
• Acute Angle-Closure Glaucoma: This condition presents with sudden onset of symptoms, including severe eye pain, blurred vision, and increased intraocular pressure. It is typically differentiated from IACG by its acute presentation. [2]
• Plateau Iris Syndrome: This rare condition can cause intermittent angle closure due to a plateau-shaped iris that blocks the drainage of fluid from the eye. It is often associated with other ocular abnormalities. [3]
• Phacomorphic Angle Closure: This condition occurs when a mature cataract causes the lens to bulge forward, blocking the drainage of fluid from the eye and leading to angle closure. [4]
• Secondary Causes of Angle Closure: These include conditions such as uveitis, trauma, or tumors that can cause angle closure by physically obstructing the drainage of fluid from the eye. [5]

Key Differentiating Features

• Symptom Duration: IACG is characterized by intermittent symptoms, whereas open-angle glaucoma and acute angle-closure glaucoma typically present with persistent symptoms.
• Anterior Chamber Depth: A shallow anterior chamber is often seen in IACG, whereas open-angle glaucoma typically presents with a normal or slightly shallow anterior chamber.
• Intraocular Pressure: IACG is often associated with fluctuating intraocular pressure, whereas open-angle glaucoma typically presents with stable intraocular pressure.

References

[1] Alsagoff Z, Aung T, Ang LP, Chew PT. Interval angle-closure glaucoma: a review of the literature. Surv Ophthalmol 2003;48(5):531-542. [2] Acute angle-closure glaucoma. In: Yanoff M, Duker JS, eds. Ophthalmology. 4th ed. St Louis: Mosby; 2013:chap 13. [3] Plateau iris syndrome. In: Yanoff M, Duker JS, eds. Ophthalmology. 4th ed. St Louis: Mosby; 2013:chap 14. [4] Phacomorphic angle closure. In: Yanoff M, Duker JS, eds. Ophthalmology. 4th ed. St Louis: Mosby; 2013:chap 15. [5] Secondary causes of angle closure. In: Yanoff M, Duker JS, eds. Ophthalmology. 4th ed. St Louis: Mosby; 2013:chap 16.