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Corneal and external disease

32 articles

Amoebic keratitis

Amoebic keratitis, also called Acanthamoeba keratitis (AK), is a rare, severe corneal infection caused by free-living amoebae, mainly Acanthamoeba, marked by pain out of proportion to findings, ring infiltrates, contact lens and water exposure, and months of biguanide-diamidine therapy.

Anaesthesia of cornea

Anaesthesia of cornea (ICD-11 9A78.6, 角膜の知覚消失), loss of corneal sensation from trigeminal or corneal nerve damage; causes include herpetic keratitis, surgery, drugs, diabetes; leads to neurotrophic keratopathy.

Arcus senilis

Arcus senilis (corneal arcus, gerontoxon): gray-white lipid ring in the peripheral cornea, common after 50, harmless to vision; premature arcus (arcus juvenilis) flags dyslipidemia and cardiovascular risk.

Bullous keratopathy

Bullous keratopathy is an eye condition in which blisters form in the cornea's surface layer because the corneal endothelium fails, often after cataract surgery or from Fuchs dystrophy.

Climatic droplet keratopathy

Climatic droplet keratopathy (CDK), also called Labrador keratopathy or spheroidal degeneration, is a rare acquired corneal degeneration from chronic UV and environmental exposure, causing golden subepithelial droplets, graded 1 to 3, treatable only by corneal transplantation.

Congenital cornea plana

Congenital cornea plana (cornea plana congenita, CNA1/CNA2) is a rare bilateral flattening of the cornea causing high hyperopia; recessive CNA2 stems from KERA (keratocan) mutations, dominant CNA1 is milder and genetically unexplained.

Contact lens-associated corneal infiltrates

Contact lens-associated corneal infiltrates, also called corneal infiltrative events, are white inflammatory cell aggregates in the cornea of lens wearers; distinguishing sterile infiltrates from microbial keratitis drives urgent management.

Corneal abscess

Corneal abscess, a suppurative form of infectious keratitis appearing as a white corneal opacity, caused by bacteria, fungi, or parasites; diagnosed by corneal scraping or suture sampling, treated with fortified topical antibiotics and sometimes keratoplasty.

Corneal deformities

Corneal deformities (ICD-11 9A78.5) are abnormal corneal shapes, chiefly keratoconus (9A78.50) and corneal staphyloma (9A78.51), causing blurred vision and irregular astigmatism, treated with lenses or keratoplasty.

Corneal degeneration

Corneal degeneration (ICD-10 H18.4, ICD-11 9A78.4) covers acquired corneal changes from aging, metabolism, or inflammation, unlike hereditary dystrophies; examples include arcus senilis, band keratopathy, and Salzmann nodular degeneration.

Corneal endotheliitis

Corneal endotheliitis is inflammation centered on the corneal endothelium, the cell layer keeping the cornea clear, causing corneal edema; most cases are viral, chiefly herpesviruses like cytomegalovirus, and delayed treatment risks irreversible endothelial cell loss.

Corneal ulcer

Corneal ulcer (ulcerative keratitis): an open sore on the cornea, usually infectious (bacterial, viral, fungal, Acanthamoeba), an ocular emergency. Contact lens wear is the leading risk factor; treated with intensive topical antibiotics.

Episcleritis

Episcleritis, also called bulbar conjunctivitis, is a benign, self-limited inflammation of the episclera between conjunctiva and sclera, with simple and nodular forms, usually idiopathic, sometimes linked to rheumatoid arthritis or IBD, and distinguished from scleritis by phenylephrine blanching.

Exposure keratitis

Exposure keratitis (exposure keratopathy, EK): corneal damage from dryness due to incomplete eyelid closure or poor blinking. Common in ICU patients (pooled prevalence 34%); treated with lubricants, moisture chambers, taping, tarsorrhaphy.

Fleck corneal dystrophy

Fleck corneal dystrophy (FCD), or François-Neetens speckled corneal dystrophy, is a rare autosomal dominant PIKFYVE-related stromal corneal dystrophy with tiny non-progressive white flecks, normal vision, and no treatment required.

Fungal keratitis

Fungal keratitis (mycotic keratitis, keratomycosis) is a fungal cornea infection causing blindness and eye loss, mainly from Fusarium, Aspergillus, and Candida after trauma or contact lens wear; treated with topical natamycin.

Granular corneal dystrophy type I

Granular corneal dystrophy type I (GCD1, Groenouw type I, classic GCD): rare autosomal dominant TGFBI p.Arg555Trp stromal corneal dystrophy with childhood-onset breadcrumb-like corneal deposits, glare, erosions, and progressive visual impairment.

Granular corneal dystrophy type II

Granular corneal dystrophy type II (GCD2, Avellino corneal dystrophy) is an autosomal dominant TGFBI (R124H) stromal corneal dystrophy with hyaline and amyloid deposits, common in East Asia, exacerbated by refractive surgery, treated with PTK and keratoplasty.

Grayson-Wilbrandt corneal dystrophy

Grayson-Wilbrandt corneal dystrophy (GWCD), also called Grayson-Wilbrandt-Hornhautdystrophie, is an extremely rare, questionable Bowman layer corneal dystrophy described in one 1966 family; autosomal dominant, removed from IC3D edition 3.

Herpes simplex keratitis

Herpes simplex keratitis (HSK, herpetic keratitis) is HSV-1 corneal infection, a leading infectious cause of blindness. Dendritic epithelial disease heals with trifluridine or acyclovir; stromal disease needs steroids plus antivirals.

Herpes simplex virus stromal keratitis

Herpes simplex virus stromal keratitis (HSK, herpes stromal keratitis) is immune-mediated corneal stromal inflammation after HSV-1 infection, causing scarring and vision loss; treated with tapered topical corticosteroids plus oral antivirals, as established by the HEDS trials.

Infectious epithelial keratitis

Infectious epithelial keratitis: rare, sight-threatening inflammation of the corneal epithelium from viral (mainly HSV-1), bacterial, fungal, or protist infection; dendritic ulcers; treated with oral acyclovir, valacyclovir, or topical antivirals.

Infectious keratitis

Infectious keratitis, also called microbial or infective corneal ulcer, is corneal infection by bacteria, fungi, viruses, or Acanthamoeba; the leading cause of corneal blindness, diagnosed by scraping, culture, PCR, and confocal microscopy.

Keratitis

Keratitis, inflammation of the cornea; microbial keratitis (bacterial, fungal, viral, Acanthamoeba) is a sight-threatening infection, with contact lens wear the main risk factor in Western settings.

Keratitis fugax hereditaria

Keratitis fugax hereditaria (keratoendotheliitis fugax hereditaria, KFH) is a rare autosomal dominant corneal autoinflammatory disease caused by the NLRP3 variant c.61G>C, causing recurrent unilateral painful attacks, blurred vision, and corneal opacities, mainly in people of Finnish descent.

Keratoconus

Keratoconus, also called conical cornea, is a bilateral noninflammatory ectatic corneal disease causing progressive thinning, cone-shaped bulging, and irregular astigmatism; managed with contact lenses, corneal cross-linking, ring segments, or keratoplasty.

Lattice corneal dystrophy type I

Lattice corneal dystrophy type I (LCD1, Biber-Haab-Dimmer, classic lattice corneal dystrophy) is a rare autosomal dominant TGFBI (5q31, R124C) amyloid stromal corneal dystrophy causing lattice lines, erosions, and vision loss from the first decade, treated with PTK or keratoplasty.

Neurotrophic keratopathy

Neurotrophic keratopathy (neurotrophic keratitis) is a rare degenerative corneal disease from trigeminal nerve damage causing loss of corneal sensation, poor healing, and ulceration; treated with cenegermin, serum drops, amniotic membrane, tarsorrhaphy, or neurotization.

Pellucid marginal degeneration

Pellucid marginal degeneration, also called pellucid marginal corneal degeneration (PMCD), is a rare, usually bilateral disorder in which a crescent-shaped band of the peripheral cornea thins progressively.

Photokeratitis

Photokeratitis (ultraviolet keratitis, arc eye, snow blindness) is a painful, usually bilateral corneal epithelial injury from UV exposure, with delayed onset 6-12 hours and self-healing within 24-72 hours.