Secondary angle-closure glaucoma occurs when the angle between the iris and the cornea is narrow or closed, as a result of another disease process in the eye.
Secondary closed angle glaucoma can be divided into two types, 1) with pupillary block, and 2) without pupillary block.
In cases of pupillary block, there is no movement of aqueous through the pupil because of 360 degree posterior synechiae between the iris and the lens, known as ‘seclusio pupillae’.
In secondary angle closure glaucoma without pupillary block, angle closure can be due to either a) contraction of an inflammatory, haemorrhagic, or vascular membrane in the angle, resulting in peripheral anterior synechiae, or b.) forward displacement of the lens-iris diaphragm, often associated with ciliary body swelling and anterior rotation.
| With pupillary block | Without pupillary block |
|---|---|
| Seclusio pupillae | Advanced neovascular glaucoma and chronic anterior uveitis |
| Subluxated lens | Cilio-choroidal effusion |
| Phacomorphic glaucoma | Capsular block syndrome without iris-capsule adhesion |
| Capsular block syndrome with 360 degree iris-capsule adhesion in pseudophakic eye | Ciliary body/iris cyst or other ciliary body or posterior segment tumour |
| Aphakic pupillary block | Contraction of retrolenticular fibrovascular tissue such as in proliferative vitreoretinopathy and retinopathy of prematurity |
| Anterior chamber lens implant without a patient iridotomy | Malignant glaucoma (cilio-lenticular block) |
Source: Kanski
Pathogenesis:
This condition is precipitated by an intumescent cataractous lense, i.e. a cataract that results in swelling congestion of the lens. Equitorial growth of the lens with age results in a slackening of the suspensory ligament, and anterior movement of the lens. This results in increased iridolenticular contract, resulting in pupillary block and iris bombé.
Features:
Presents similarly to PACG with a shallow anterior chamber and mid dilated pupil, with a cataract.