Acute visual disturbance / loss | Medical Council of Canada
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MCC Examination Objectives Medical expertVisual disturbance/lossAcute visual disturbance / loss

Acute visual disturbance / loss

Version: March 2022
Legacy ID: 115-1


Sudden decreases in visual acuity or visual field are symptoms that require urgent evaluation. The outcome may depend on early, accurate diagnosis and timely treatment. Many patients require an urgent ophthalmologic opinion.

Causal Conditions

(list not exhaustive)

  1. Painless
    1. Vascular (e.g., retinal artery occlusion, giant cell arteritis)
    2. Neurologic (e.g., optic neuritis, stroke)
    3. Retinal (e.g., retinal detachment)
    4. Other (e.g., conversion disorders)
  2. Painful
    1. Glaucoma
    2. Inflammatory (e.g., uveitis, corneal ulcer)
    3. Other (e.g., traumatic)

Key Objectives

Given a patient with an acute decrease in visual acuity or visual field, the candidate will complete a focused history and physical examination, and order relevant investigations to determine the most likely diagnosis. The candidate will initiate an appropriate management plan. In particular, the candidate will recognize features that indicate the need for immediate intervention, including the need for urgent referral to an ophthalmologist.

Enabling Objectives

Given a case of sudden decrease in visual acuity or visual field the candidate will

  1. list and interpret critical clinical findings, including
    1. the characteristics of the visual loss and other relevant medical history;
    2. results of an appropriate eye examination; and
    3. the presence of a vision-threatening condition;
  2. list and interpret critical investigations (e.g., imaging, erythrocyte sedimentation rate or C-reactive protein, temporal artery biopsy); and
  3. construct an effective initial management plan, including
    1. initiating urgent medical therapy when appropriate; and
    2. referring the patient for specialized care if necessary.