aka Ophthalmology Befuddler 027
A 56 year-old female presents with sudden onset loss of vision in her right eye. She a past medical history of hypertension, hyperlipidema and medication-controlled diabetes mellitus type 2. Her medications include aspirin, ramipril, atorvastation and metformin. On examination she has 6/60 vision in her right eye.
You perform fundoscopy and observe the following appearance:
Q1. What is the diagnosis?
Central retinal vein occlusion
Sudden painless loss of vision, in a pateint with risk factors and a ‘blood and thunder’ retinal appearance.
Q2. What are the predisposing factors and associated conditions?
There are lots:
- old age
- diabetes mellitus
- hypercoagulable state
- atherosclerosis (vein is compressed by adjacent artery)
- retrobular compressive lesions (e.g. thyroid disease, orbital tumour)
Q3. What features on history and examination should be looked for?
- sudden and painless loss of vision
- assess for risk factors/ underlying causes (see Q2)
- Visual acuity — variable depending on severity and duration since onset
- A Marcus-Gunn pupil may be present if ischemic CRVO (relative afferent pupillary defect = RAPD)
- Red reflex — may be abnormal
- Fundoscopy — large areas of hemorrhage:
- non-ischemic CRVO —
dilated tortuous veins, retinal hemorrhages, cotton wool spots, retinal edema, disc swelling.
- ischemic CRVO (more severe) —
classic ‘blood and thunder’ appearance from widespread hemorrhages that obscure most fundal details. Neovascularisation.
Q4. What is the management?
- Refer to an ophthalmologist — photocoagulation may be performed if there is neovascularisation.
- Refer to a physician for ongoing work-up and treatment of underlying causes
- Screen for risk factors (cardiovascular disease, diabetes, vasculitis, etc)
- Consider low-dose aspirin (unproven)
Q5. How does branch retinal vein occlusion differ from this condition?
A branch retinal vein occlusion only affects a sector of the retina corresponding to the distribution of the affected branch. Visual loss is limited to a segment of the visual field.
- Ehlers JP, Shah CP, Fenton GL, and Hoskins EN. The Wills Eye Manual: Office and Emergency Room Diagnosis and Treatment of Eye Disease (5th edition). Lippincott Williams & Wilkins, 2008.
- Jeff Mann EM Guidemaps. Loss of vision.
- Marx JA, Hockberger R, Walls RM. Rosen’s Emergency Medicine: Concepts and Clinical Practice, 7th edition (2009) Mosby, Inc. [mdconsult.com]
- NSW Statewide Opthalmology Service. Eye Emergency Manual — An illustrated Guide, 2007. [link to free pdf]