Acute Angle-Closure Glaucoma

Question 1

What is acute angle-closure glaucoma?

Answer 1

A medical emergency caused by a sudden increase in intraocular pressure due to blockage of aqueous humour outflow.

Question 2

What is the pathophysiology of acute angle-closure glaucoma?

Answer 2

Blockage of the trabecular meshwork by the iris prevents aqueous humour drainage, leading to a rapid rise in intraocular pressure.

Question 3

What are the symptoms of acute angle-closure glaucoma?

Answer 3

Severe eye pain, blurred vision, headache, nausea, vomiting, and seeing halos around lights.

Question 4

What are the clinical signs of acute angle-closure glaucoma?

Answer 4

Red eye, mid-dilated fixed pupil, corneal clouding, and a hard, tender eyeball on palpation.

Question 5

What is the prevalence of acute angle-closure glaucoma?

Answer 5

It is less common than open-angle glaucoma but more acute and sight-threatening.

Question 6

What are the risk factors for acute angle-closure glaucoma?

Answer 6

Age >50, hyperopia (farsightedness), female gender, family history, and Asian or Inuit ethnicity.

Question 7

What are the triggers for acute angle-closure glaucoma?

Answer 7

Low light conditions, use of mydriatic drugs, or stress.

Question 8

What investigations are used to diagnose acute angle-closure glaucoma?

Answer 8

Tonometry (measuring intraocular pressure), gonioscopy, and slit-lamp examination.

Question 9

What intraocular pressure level is typically seen in acute angle-closure glaucoma?

Answer 9

Elevated intraocular pressure, often exceeding 40-50 mmHg.

Question 10

What are the differential diagnoses for acute angle-closure glaucoma?

Answer 10

Conjunctivitis, anterior uveitis, corneal abrasion, or scleritis.

Question 11

What is the first-line management of acute angle-closure glaucoma?

Answer 11

Lowering intraocular pressure with medications and preparing for definitive treatment, such as laser iridotomy.

Question 12

What medications are used to lower intraocular pressure in acute angle-closure glaucoma?

Answer 12

IV acetazolamide, topical beta-blockers (e.g., timolol), and miotics (e.g., pilocarpine).

Question 13

What is the role of acetazolamide in acute angle-closure glaucoma?

Answer 13

It reduces aqueous humour production, lowering intraocular pressure.

Question 14

What is the role of pilocarpine in acute angle-closure glaucoma?

Answer 14

It constricts the pupil, opening the trabecular meshwork and facilitating aqueous humour drainage.

Question 15

What definitive treatments are available for acute angle-closure glaucoma?

Answer 15

Laser peripheral iridotomy or surgical iridectomy.

Question 16

What is a laser peripheral iridotomy?

Answer 16

A laser creates a hole in the peripheral iris to allow aqueous humour to bypass the blocked trabecular meshwork.

Question 17

What are the complications of untreated acute angle-closure glaucoma?

Answer 17

Permanent vision loss, optic nerve damage, and blindness.

Question 18

What is the prognosis for acute angle-closure glaucoma with treatment?

Answer 18

With prompt treatment, vision can often be preserved, but delay can result in irreversible damage.

Question 19

What lifestyle advice is recommended for patients with a history of acute angle-closure glaucoma?

Answer 19

Avoid mydriatic drugs, regular eye exams, and educate about recognising early symptoms.

Question 20

What is gonioscopy, and why is it used in acute angle-closure glaucoma?

Answer 20

Gonioscopy assesses the anterior chamber angle to confirm the diagnosis and evaluate the extent of closure.

Question 21

What is the role of mannitol in acute angle-closure glaucoma?

Answer 21

Mannitol, an osmotic diuretic, reduces intraocular pressure by drawing fluid out of the eye.

Question 22

What are the systemic symptoms associated with acute angle-closure glaucoma?

Answer 22

Nausea, vomiting, and severe headache.

Question 23

Why is acute angle-closure glaucoma considered an ophthalmic emergency?

Answer 23

Delay in treatment can lead to rapid and permanent vision loss.

Question 24

What is the role of prophylactic laser iridotomy?

Answer 24

It is used to prevent acute angle-closure glaucoma in the unaffected eye or in patients at high risk.

Question 25

What imaging techniques are used to assess anterior chamber anatomy in acute angle-closure glaucoma?

Answer 25

Anterior segment optical coherence tomography (AS-OCT) or ultrasound biomicroscopy.