A patient presenting with a sudden loss of vision always needs urgent ophthalmic investigation, diagnosis and management. This will require using a range of imaging and serological tests to signpost the appropriate treatment.

Common presentation of symptoms

• Decreased vision in one or both eyes described as a ‘deep, boring pain’ with accompanying photophobia and distorted colour perception.
• Sudden loss of vision in one eye with no pain but experiencing flashes and dark spots in the peripheral vision.
• Acute decreased vision in one eye with a headache over the affected eye which the patient says becomes worse when chewing. Experiencing pain, fatigue and recent unintentional weight loss.

Acute loss of vision, with varying symptoms, can present in both males and females of any age and can have a wide range of etiologies which are generally time-sensitive and need immediate investigation and diagnosis to achieve the best outcome.

Evaluation of symptoms

The presence of pain or not can determine the issue. Before diagnosis can be achieved, the history and background of the patient need to be taken. 

Firstly, ascertain whether pain is present or not and if the visual disturbance is in one or both eyes. For example, acute glaucoma can present with deep, boring pain and nausea or vomiting; optic neuritis causes increased pain with eye movement.

Vital questions include:

• Is the loss of vision sudden (acute), or was there a previous loss of vision?
• Is there redness in the eye or discharge from the eye?
• Ask about any trauma or injury to the eye.

Consider any other symptoms which may indicate a neurological deficit, including weakness accompanying a stroke.

Medical history should be looked at. Is there vascular disease including diabetes, hypertension or  blood clotting issues? Evaluate the refractive status, as near-sightedness means a higher risk of retinal detachment. Obtain a complete list of medications currently taken by the patient.

Physical examination

A close inspection of the affected eye should be conducted using the appropriate tools. A vision test using a standard eye chart can be assessed. A vision field test can be instructive.

Light sensitivity and pupil reflex, along with extraocular movements should be examined.

A high yield test to evaluate the lens, anterior chamber, optic nerve and posterior chamber/retina is advised.

Immediate treatment is required for acute central retinal artery occlusion, acute glaucoma and giant cell arteritis. Retinal detachment requires an urgent (same day) referral to an ophthalmology consultant.

Retinal detachment

This can sometimes occur through trauma but more often than not is associated with rhegmatogeny, exudation and traction. Common symptoms are sudden onset of new floaters, black spots and light flashes. There can be visual loss in the early stage, but vision can be severely affected where the macula or central retina is affected. The condition is usually painless with no redness of the eye. An ocular ultrasound examination is the best method of retinal detachment diagnosis which will show a reflective and mobile undulating membrane.

Urgent referral to an ophthalmic consultant for treatment is needed if a retinal detachment is suspected.