Author:

Editor(s):

Updated:

ULY CLINIC

20 Septemba 2025, 02:05:14

Vision loss

Vision loss — the inability to perceive visual stimuli — can be sudden or gradual, temporary or permanent. The deficit may range from slight impairment to total blindness. Causes include ocular, neurologic, systemic disorders, trauma, or drug-related toxicity. Early and accurate diagnosis is crucial for optimal visual outcomes.

Pathophysiology

Ocular causes: Cataracts, glaucoma, retinal artery or vein occlusion, macular degeneration, vitreous hemorrhage, or trauma impair light perception or image formation.
Neurologic causes: Optic neuritis, optic atrophy, pituitary tumors, stroke, or cortical lesions disrupt transmission of visual signals to the brain.
Systemic/metabolic causes: Diabetes mellitus, hypertension, temporal arteritis, or infections may damage ocular structures or retinal vasculature.
Drug-induced toxicity: Chloroquine, ethambutol, digoxin, quinine, or methanol impair retinal or optic nerve function.
Trauma: Penetrating, blunt, or chemical injury may acutely damage ocular structures and cause partial or total vision loss.

History and Physical Examination

History

Onset: sudden vs gradual.
Pattern: unilateral or bilateral, partial or total, transient or persistent.
Symptoms: photophobia, eye pain, floaters, visual field defects, halos around lights.
Associated systemic conditions: hypertension, diabetes, thyroid disease, rheumatic or vascular disorders, infections, cancer.
Ocular history: previous eye disease, trauma, surgery, or family history of eye disorders.

Examination Tip: Testing Visual Acuity

Snellen letter chart (patients >6 years, literate):Patient sits or stands 20′ (6 m) from chart, covers one eye, and reads the smallest line visible. Record fraction: numerator = distance from chart, denominator = distance a normal eye reads that line. Normal vision = 20/20.
Snellen symbol chart (children 3–6 years or illiterate patients):Patient indicates direction of the E’s arms. Record fraction as above.
If unable to read largest letter at 20′, move closer and record actual distance (e.g., 3/200).

Physical Examination

Assess visual acuity with best available correction.
Inspect eyelids, conjunctiva, sclera for edema, redness, drainage, or lacerations.
Check lid closure and ptosis.
Examine cornea and iris for scars, irregularities, or foreign bodies.
Evaluate pupils: size, shape, direct and consensual light reflex, accommodation.
Assess extraocular muscles via six cardinal fields of gaze.

Medical causes

Cause	Onset	Key Features	Associated Findings	Pathophysiology	Management
Amaurosis fugax	Transient	Recurrent unilateral vision loss, seconds to minutes	Transient weakness, hypertension, elevated IOP	Temporary retinal ischemia	Identify source of emboli, vascular risk management
Cataract	Gradual	Painless visual blurring, milky white pupil	Progressive loss of vision	Lens opacity → impaired light transmission	Surgical extraction
Concussion	Acute	Blurred or double vision, temporary vision loss	Headache, LOC changes, amnesia, nausea, vomiting	Transient CNS dysfunction post-trauma	Supportive care, rest, monitor for complications
Diabetic retinopathy	Gradual	Visual blurring	Retinal edema, hemorrhage, microaneurysms	Retinal vascular damage due to hyperglycemia	Glycemic control, laser therapy, anti-VEGF injections
Endophthalmitis	Acute	Severe unilateral pain, vision loss	Redness, discharge, history of trauma or surgery	Intraocular infection/inflammation	Intravitreal antibiotics, surgery if needed
Glaucoma (acute angle-closure)	Acute	Eye pain, halos, nausea, vomiting	Rock-hard eye, nonreactive pupil, cloudy cornea	Sudden IOP elevation → optic nerve damage	Pressure-reducing drops, IV acetazolamide, ophthalmology consult
Glaucoma (chronic open/angle closure)	Gradual	Peripheral vision loss, aching eyes	Halo vision, reduced night vision	Progressive optic nerve damage	Eye drops, laser/surgery
Macular degeneration	Gradual	Central vision loss	Blurring, distorted vision	Retinal macular degeneration	Anti-VEGF therapy, low-vision aids
Ocular trauma	Acute	Sudden unilateral or bilateral vision loss	Eyelid edema, laceration, intraocular content extrusion	Mechanical or penetrating injury	Emergency ophthalmology evaluation
Optic neuritis	Acute/subacute	Unilateral vision loss, eye pain	Sluggish pupillary response, hyperemic optic disk	Inflammation/demyelination of optic nerve	Corticosteroids, treat underlying cause
Optic atrophy	Gradual	Progressive visual field loss	Color vision changes, optic disk pallor	Degeneration of optic nerve fibers	Address underlying cause; visual rehabilitation
Pituitary tumor	Gradual	Blurred vision, hemianopia	Diplopia, nystagmus, ptosis, headache	Compression of optic chiasm	Surgery, radiation, endocrine management
Retinal artery occlusion	Acute	Sudden unilateral vision loss	Sluggish direct pupillary response	Arterial obstruction → retinal ischemia	Ophthalmology emergency, ocular massage, vasodilation
Retinal detachment	Acute or gradual	Painless visual field defect, shadow/curtain	Floaters, sudden vision loss	Separation of retina from underlying epithelium	Surgical repair
Retinal vein occlusion	Acute	Unilateral decrease in visual acuity	Variable vision loss	Retinal venous obstruction → edema/hemorrhage	Laser therapy, anti-VEGF therapy
Stevens-Johnson syndrome	Acute	Corneal scarring, vision loss	Conjunctivitis, systemic symptoms	Immune-mediated mucocutaneous reaction	Ophthalmology care, supportive therapy
Temporal arteritis	Acute/subacute	Vision loss, blurring	Throbbing unilateral headache, malaise, fever	Inflammation of temporal arteries → ischemia	High-dose corticosteroids
Rift Valley fever	Acute	Vision loss	Fever, myalgia, encephalitis in severe cases	Retinal inflammation	Supportive care, manage systemic disease
Drugs	Gradual	Vision loss, visual field defects	Retinal pigmentation changes, optic neuropathy	Drug-induced retinal or optic nerve toxicity	Discontinue offending drug, supportive therapy

Emergency interventions

Sudden vision loss may indicate central retinal artery occlusion or acute angle-closure glaucoma — urgent ophthalmology consultation required.
Central retinal artery occlusion: ocular massage, increase CO₂ levels (rebreathing or Venturi mask) to restore retinal blood flow.
Acute angle-closure glaucoma: measure IOP, administer pressure-lowering eye drops, IV acetazolamide.

Special considerations

Vision loss can cause significant anxiety.
Orient patient to surroundings, ensure safety, announce presence when approaching.
Darken room for photophobia; advise sunglasses.
Avoid contamination of the unaffected eye; maintain hand hygiene.
Prepare for surgery if indicated.

Patient counseling

Educate on environmental safety to prevent injury.
Stress importance of hand hygiene and avoiding rubbing eyes.
For progressive or permanent vision loss, refer to low-vision or social support services.

Pediatric pointers

Causes include optic nerve glioma, retinoblastoma, congenital infections (rubella, syphilis), retrolental fibroplasia, Marfan syndrome, retinitis pigmentosa, amblyopia.
Early detection is critical for treatment and vision preservation.

Geriatric pointers

Reduced visual acuity may result from morphologic retinal changes, decreased rod/cone function, or ocular diseases (cataract, glaucoma, macular degeneration).
Difficulty looking upward is common.
IOP increases with age; monitor for glaucoma.

References

Biswas J, Krishnakumar S, Ahuja S. Manual of Ocular Pathology. New Delhi, India: Jaypee – Highlights Medical Publishers; 2010.
Gerstenblith AT, Rabinowitz MP. The Wills Eye Manual. 7th ed. Philadelphia (PA): Lippincott Williams & Wilkins; 2012.
Levin LA, Albert DM. Ocular Disease: Mechanisms and Management. 3rd ed. London (UK): Saunders Elsevier; 2010.
Roy FH. Ocular Differential Diagnosis. Clayton, Panama: Jaypee – Highlights Medical Publishers, Inc.; 2012.
American Academy of Ophthalmology. AAO Basic and Clinical Science Course. San Francisco (CA): AAO; 2021.
Kanski JJ, Bowling B. Clinical Ophthalmology: A Systematic Approach. 9th ed. London (UK): Elsevier; 2011.
Morgan ML, Katsnelson J. Ophthalmology Review Manual. 5th ed. Philadelphia (PA): Wolters Kluwer; 2017.
Foroozan R. Acute visual loss: Approach to diagnosis and management. Ophthalmol Clin North Am. 2018;31:1–12.
Kanski JJ, Salmon JF. Clinical Ophthalmology: A Systematic Approach. 8th ed. Elsevier; 2016.
American Optometric Association. Comprehensive Eye and Vision Examination Guidelines. St. Louis (MO): AOA; 2020.
Wong TY, Mitchell P. The eye in systemic disease. Lancet. 2007;370:1361–1373.
Choudhury P, Choudhury A. Pediatric ocular emergencies. Indian J Ophthalmol. 2011;59:97–103.
Taylor D. Geriatric ophthalmology: Age-related changes in vision and ocular anatomy. Clin Geriatr Med. 2015;31:285–300.