This page summarises the secondary causes of closed-angle glaucoma. These conditions generally involve changes to the ocular structure where the anterior chamber angle is compromised.
Neovascular Glaucoma
Glaucomatous damage caused by rubeosis iridis
Pathology
Retinal ischemia → hypoxia of retinal cells → general release of angiogenic → rubeosis iridis → fibrovascular proliferation at iridocorneal angle → PAS → angle-closure → obstruction of the trabecular meshwork
- Causes open-angle first, then closed-angle glaucoma
- Causes of rubeosis iridis: CRVO | CRAO | DM | RD | ocular ischemic syndrome
Diagnostics
Presentation
- Onset after an episode of CRVO
- Vascular risk factors (e.g smoking/diabetes)
Investigations
- Rubeosis iridis + elevated IOP + glaucomatous vision change
Management
- Early (to reduce neovascularization) → PRP ± intravitreal anti-VEGF
Medical
- POAG meds protocol for IOP
- Pain → cycloplegics
Surgical
- Good visual prognosis → glaucoma drainage device (tube).
- Bad visual prognosis → cyclodiode laser destruction of the ciliary body
Miotics are contraindicated because can they worsen synechial angle closure
Aqueous Misdirection Syndrome
Posterior misdirection of aqueous causes anterior displacement of the vitreous, lens and ciliary body, leading to angle closure.
Diagnostics
Presentation
- Typically presents post-surgery in hyperopes (short AC length)
- Acute highly raised IOP + Shallow AC + no pupil block
Management
- IOP → IV acetazolamide
- Either laser or Surgical IOP procedures making sure there is a peripheral iridotomy and it is patent
Iridocorneal Endothelial Syndrome
Unilateral** secondary closed-angle glaucoma due to **abnormal corneal epithelium structure
Pathology
Iris/corneal tissue migrates across the AC angle and obstructs aqueous drainage. The cause is unknown but thought to be HSV related.
- There are 2 eponymous overlapping syndromes:
- Chandler syndrome is when the tissue is corneal
- Cogan-Reese syndrome is when iris stromal tissue change leads to naevi/nodular formations.
Diagnostics
Presentation
- Unilateral pain and blurred vision in a woman in her 3rd decade of life
Investigation
- Slit-lamp → corneal oedema, corneal guttata, pupil/iris abnormalities
- Gonioscopy → PAS
- Specular microscopy → corneal endothelial abnormalities
Management
- Depends on severity. Starting with topical IOP lowering agents and progressing to surgery and laser therapies
General principles of management apply to all glaucomatous diseases. Starting with IOP lowering medications and progressing to surgery/laser.
