Eyes & Vision

A sudden obstruction of aqueous outflow causes a rapidly painful rise in intraocular pressure, producing a red eye with visual symptoms and vomiting that needs same-day ophthalmology treatment.

Age-related macular degeneration damages the macula and therefore central vision; suspected late wet active AMD needs urgent macular-service referral, OCT and prompt anti-VEGF treatment, while dry AMD needs risk-factor advice, self-monitoring, low-vision support and clear safety-netting.

Inflammation of the iris and ciliary body causing a painful photophobic red eye; it needs urgent ophthalmic assessment because early treatment prevents synechiae and sight-threatening complications.

Blepharitis is chronic inflammation of the eyelid margins: anterior disease affects the lash line, while posterior disease is usually meibomian gland dysfunction. It causes sore, gritty, crusted lids and evaporative dry-eye symptoms; long-term lid hygiene is the foundation, while pain, visual change or a very red eye needs urgent assessment for another ocular diagnosis.

Progressive opacification of the crystalline lens scatters and blocks incoming light, causing gradual, painless blurring of vision that only surgery (replacing the lens) can reverse, because the damaged protein structure cannot be cleared or treated medically.

Central retinal artery occlusion is an ocular stroke causing sudden, painless monocular visual loss; it needs immediate stroke and ophthalmology assessment, with urgent exclusion and treatment of giant cell arteritis when clinically suspected.

Central retinal vein occlusion causes sudden or subacute painless unilateral visual loss with widespread retinal haemorrhages and macular oedema; distinguish non-ischaemic from ischaemic disease because ischaemia carries a high risk of iris/angle neovascularisation and neovascular glaucoma.

Chronic open-angle glaucoma is progressive optic-nerve damage with an open drainage angle and corresponding visual-field loss; it is usually painless and peripheral vision is lost first, so diagnosis depends on structured testing and treatment aims to prevent further irreversible loss.

A superficial red, gritty, itchy or discharging eye caused by infection, allergy or irritation; preserved vision and a comfortable cornea support the diagnosis, while pain, photophobia, reduced vision, contact-lens use or neonatal disease needs urgent escalation.

A corneal abrasion is a traumatic defect of the corneal epithelium causing severe pain, watering and photophobia; confirm it with fluorescein, exclude a foreign body or open-globe injury, and treat contact-lens-associated abrasions as higher-risk for microbial keratitis.

Diabetes damages retinal microvasculature, progressing from non-proliferative disease to ischaemia-driven neovascularisation, while diabetic macular oedema is a separate sight-threatening pathway; screening and stage-specific ophthalmic treatment prevent avoidable visual loss.

Episcleritis is usually self-limiting inflammation of the superficial episclera, causing a sectoral or diffuse red eye with mild aching and preserved vision; its key clinical task is to exclude the painful, potentially sight-threatening deep inflammation of scleritis.

Infective keratitis is a sight-threatening corneal infection causing a painful red photophobic eye with an infiltrate or ulcer; contact-lens-associated disease and Acanthamoeba require emergency ophthalmology, microbiological assessment and specialist antimicrobial treatment.

Optic neuritis is inflammation of the optic nerve causing subacute visual loss, impaired colour vision, a relative afferent pupillary defect and often pain on eye movement; it needs urgent eye assessment and may be the first presentation of multiple sclerosis or antibody-mediated disease.

Papilloedema is optic-disc swelling caused by raised intracranial pressure; it is a sign rather than a diagnosis and needs urgent confirmation, brain imaging with venous imaging and specialist management to prevent irreversible visual loss or neurological deterioration.

Retinal detachment separates the neurosensory retina from its support tissues and can cause permanent sight loss; new flashes, floaters, a curtain or sudden visual loss need urgent retinal assessment, especially before the macula detaches.

Scleritis is severe inflammation of the sclera causing deep eye pain, a dark red or violaceous tender eye and possible visual loss; it is an ophthalmic emergency because necrotising or posterior disease can destroy the eye and may reveal systemic autoimmune, vasculitic or infectious disease.

Subconjunctival haemorrhage is a superficial bleed beneath the conjunctiva causing a sharply demarcated bright-red patch with normal vision; it is usually harmless, but pain, visual change or trauma means the diagnosis must be reconsidered urgently.