Acute visual loss

Overview of acute visual loss

Acute visual loss refers to a sudden decrease in vision that can occur over a period of seconds to days. It is a symptom that can be caused by a variety of ophthalmic and neurological conditions. Understanding the underlying cause is crucial for effective management and treatment.

Causes

Acute visual loss can be attributed to several causes, which can be broadly categorized into ocular and neurological origins.

Ocular Causes

• Retinal detachment: This occurs when the retina peels away from its underlying layer of support tissue. Symptoms include a sudden increase in floaters, flashes of light, and a shadow or curtain over part of the visual field.
• Vitreous hemorrhage: Bleeding into the vitreous humor can cause sudden visual loss. It is often associated with diabetic retinopathy or retinal tears.
• Central retinal artery occlusion (CRAO): This is an ophthalmic emergency where the blood supply to the retina is blocked, leading to sudden, painless vision loss.
• Central retinal vein occlusion (CRVO): Similar to CRAO, but involves blockage of the retinal vein, leading to swelling and hemorrhage in the retina.

Neurological Causes

• Optic neuritis: Inflammation of the optic nerve can cause sudden vision loss, often associated with pain on eye movement. It is commonly linked to multiple sclerosis.
• Stroke: A stroke affecting the visual pathways in the brain can lead to sudden visual loss, often affecting one side of the visual field.
• Migraine: Ocular migraines can cause temporary visual disturbances, including loss of vision, often accompanied by a headache.

Diagnosis

The diagnosis of acute visual loss involves a thorough medical history and physical examination, including:

• Visual acuity testing: Using a Snellen chart to assess the level of vision loss.
• Fundoscopy: Examination of the retina and optic nerve head to identify any abnormalities.
• Visual field test: To determine the extent and pattern of vision loss.
• Imaging studies: Such as MRI or CT scan to evaluate neurological causes.

Snellen chart used for visual acuity testing

Management

The management of acute visual loss depends on the underlying cause:

• Retinal detachment: Surgical intervention, such as vitrectomy or scleral buckle, is often required.
• Vitreous hemorrhage: Observation or surgical intervention may be necessary, depending on the severity and cause.
• CRAO and CRVO: Immediate treatment may involve ocular massage, lowering intraocular pressure, or thrombolytic therapy.
• Optic neuritis: Treatment often involves corticosteroids to reduce inflammation.

Prognosis

The prognosis for acute visual loss varies widely depending on the cause and the timeliness of treatment. Early diagnosis and intervention are critical for the best possible outcome.

Related pages

• Vision impairment
• Ophthalmology
• Neurology