Previous angle closure glaucoma
 

Glaucoflecken  Laser peripheral iridotomy. This is  usually situated at the periphery in the superior iris.  Surgical iridectomy in an eye with previous acute glaucoma.  Notevthe irregular pupil.

The anterior chamber is usually shallow but may be normal in pseudophakia. The lens contains white opacities anteriorly.  The iris may show atrophy from ischaemic changes with irregular pupil which may react poorly to light. Peripheral iridotomy is usually present. You need to assess the patency of the iridotomies.  In the examination: remember that no all cases of acute glaucoma are treated with laser iridotomies. You may have patients who had  had surgical iridectomies. With a casual examination, this may be mistaken for trabeculectomy without a  functioning bleb. The clue to this is the absence of a scleral flap, glaucoflecken and iris changes examine the opposite eye for prophylactic treatment wither laser or surgical.

Questions:

1. What is glaucoflecken?

Answer
There are opacities behind the anterior lens capsule resulting from anterior epithelium necrosis.

2. How does plateau iris syndrome differ from primary angle closure glaucoma?

Answer
In primary angle closure glaucoma, the mechanism is due to pupillary block. Whereas in plateau iris syndrome, the main mechanism is caused by occlusion of the trabecular meshwork by the anteriorly positioned peripheral iris.
Patients with plateau iris syndrome tends to be younger (fourth or fifth decade of life) than patients with primary angle closure glaucoma.
The anterior chamber in plateau iris syndrome is deep centrally whereas in primary angle closure glaucoma it is shallow both centrally and peripherally.
Patients with plateau iris syndrome may not respond to laser iridotomy like primary angle closure glaucoma. Laser peripheral iridoplasty or miotic therapy may be needed.
 

3. What are the ocular risk factors for primary angle closure glaucoma?

Answer
Shallow anterior chamber
hypermetropia
small corneal diameter
short axial length of globe
large crystalline lens

4. What tests can help to predict which patient would develop acute angle closure glaucoma?

Answer
Patients with narrow angle may develop acute angle closure glaucoma when the pupil is dilated due to pupillary block. Provocative tests may be used to identify the latent cases, the result is positive if there is 8 mmHg pressure rise in the first hour.
The provocative test may be physiological for example the dark room test in which the pressure of the test is checked when the pupil becomes dilated in the dark or pharmacological with 10% phenylephrine (which is reversible with thymoxamine).
 

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