Clinical features

Presentation of primary closed angle glaucoma may be:

• latent
  • asymptomatic but a shallow anterior chamber with a narrow angle is observed
  • intra-ocular pressure is normal
  • the other eye may have experienced an acute or subacute closure
    
    
• subacute
  • presentation is with haloes around small sources of light and impaired vision due, to corneal oedema, frontal headache and ocular pain. The attacks recur and are most apparent when mydriasis is present, for example, while watching T.V. in a darkened room
  • miosis of the pupil which occurs when the patient sleeps or enters a brighter environment will abort the attack (1)
  • examination between attacks does not reveal any abnormality (except for a narrow angle and a shallow anterior chamber) (1), but during an attack, the pupil will be semidilated and the cornea hazy. The eyes are at risk of an acute episode ~
    
    
• acute
  • a sudden severe rise of intra-ocular pressure presents with:
    • an acute loss of vision in the affected eye
    • severe periocular pain and congestion
    • nausea and vomiting are common (1)
  • there may be a history of previous subacute attacks (in around 50% of cases). Congestion is caused by ischaemia of the iris which results in tissue damage and the release of irritant autolytic products
  • examination reveals a characteristic picture:
    • a stony hard eye marked pericorneal injection
    • a semi-dilated, non-reacting pupil
    • a hazy corneal reflex
    • the anterior chamber is narrowed
    • the pupil is oval (with a vertical long axis)
    • high intra ocular pressure (40 – 80 mmHg) (1)
    • visualisation of the fundus not possible
      
      
• chronic
  • angle closure may develop slowly with features similar to those of chronic simple glaucoma.
  • usually no pain but there can be some discomfort (2)
  • the intra-ocular pressure is moderately raised with optic nerve cupping and visual defects.

Reference:

• (1) The College of Optometrists 2009. Glaucoma (primary angle closure) (PACG)
• (2) European Glaucoma Society (EGS) 2008. Terminology and guidelines for glaucoma (3rd edition)