Date amended:
External
Statements of Principles
Current RMA Instruments
Reasonable Hypothesis SOP
5 of 2021
Balance of Probabilities SOP
6 fo 2021
Changes from previous Instruments

Document

ICD Coding
  • ICD-9-CM Codes: 365.2, 365.59, 365.61
  • ICD-10-AM Codes: H40.2, H40.5
Brief description

Angle closure glaucoma is an optic neuropathy involving progressive peripheral visual field loss followed by central field loss. This usually (but not always) occurs in the presence of elevated intraocular pressure.  "Angle closure" refers to the anterior chamber angle, between the iris and the innermost surface of the cornea, which becomes narrowed or closed in this condition, unlike open-angle glaucoma, where it remains normal. 

Confirming the diagnosis

A diagnosis of glaucoma is based on findings of optic nerve damage on fundus examinaiton and visual field abnormalities. Slit lamp gonioscopy is used to visualise the anterior chamber angle and identify angle-closure glaucoma. The diagnosis needs to be made by an ophthalmologist.

Additional diagnoses covered by SOP
  • chronic angle closure glaucoma with progressive neuropathy 
  • primary angle-closure glaucoma
Conditions that may be covered by SOP (further information required)
  • neovascular glaucoma – this may be open-angle or angle-closure in type.
Conditions not covered by SOP
  • borderline glaucoma
  • chronic simple glaucoma* - open-angle glaucoma SOP
  • congenital glaucoma#
  • ghost cell glaucoma* - open-angle glaucoma SOP
  • phacolytic glaucoma* - open-angle glaucoma SOP
  • pigmentary glaucoma* - open-angle glaucoma SOP
  • open-angle glaucoma*

* Another SOP applies

# Non-SOP condition

Clinical onset

The clinical presentation is variable.  More severe cases present with loss of vision, severe eye pain, headache, nausea and vomiting. Less severe cases may be asymptomatic or present with loss of peripheral vision. 

Clinical worsening

Angle closure glaucoma requires urgent management to reduce intraocular pressure and reverse the angle closure with laser therapy.  Damage to the optic nerve is irreversible once sustained.  Progression of the disease can be slowed or halted with appropriate therapy.  Worsening would be assessed by the degree of visual imapirment (primarily visual field loss).

Comments

There are separate RMA SOPs for angle-closure glaucoma and open-angle glaucoma.

Of all non-congenital glaucoma cases:

  • Approximately 85% are primary open-angle glaucoma.
  • Approximately 10% are primary angle-closure glaucoma.
  • Approximately 5% are secondary glaucoma, either open-angle or angle-closure.

Open angle glaucomas generally present with chronic, painless, progressive loss of vision.  Whereas, angle closure glaucomas generally present as a painful red eye.

This SOP contains a factor that applies only to acute angle-closure glaucoma.  To apply this factor you will therefore need information from an ophthalmologist that establishes this specific diagnosis.  It may be possible to finalise the claim without this information, particularly if the claim can succeed using another factor.