Corneal Ulcer

Corneal Ulcer Bacterial Keratitis

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Natural defenses   

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Eyelids Epithelial barrier Tears

Risk factors     

Lid abnormalities; Dry eye; Steroids ; prior herpetic infection; Contact lens user; LASIK; Immune compromise Trauma lagophthalmos; neurotrophic keratitis

Pathophysiology 

Interruption of an intact corneal epithelium -> entrance of microorganisms into the corneal stroma -> proliferate and cause ulceration -> inflammation, necrosis -> corneal perforation/ scar tissue

Pathophysiology 

Organisms – staphylococcus  streptococcus,  pseudomonas,  Enterobacteriaceae (including Klebsiella, Enterobacter, Serratia, and Proteus)  Moraxella . 

Clinical Features         

Rapid onset of pain, photophobia Decreased vision. Lid erythema, edema; Conjunctival congestion; chemosis; lacrimation; Mucopurulent discharge Ulceration of the epithelium; Corneal infiltrate Dense, suppurative stromal inflammation and surrounding stromal edema Stromal tissue loss;

Small ulcer with active area towards the center. The central cornea is hazy and shows Descemet's

Clinical Features 

Anterior chamber hypopyon 

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–

inflammation;

Esp. with pseudomonas pyocyanea and pneumococci -> called hypopyon ulcers

Regressive stage -> vascularization -> cicatrization -> opaque scar

Diagnosis  

Clinical history & examination Slit lamp examination – size/depth/ location/ AC reaction 

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Fluorescein stain

Confirmation – corneal scraping for smear and culture 

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Scrapings including the edges -> plated in blood, chocolate, and Sabouraud agar plates Stained smears with gram, Giemsa,KOH

Treatment 

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Initial therapy – broad spectrum topical Antibiotics, (no organisms in slide smear) Fluoroquinolones include ciprofloxacin, ofloxacin, moxifloxacin or gatifloxacin. Fortified Tobramycin 1 drop every hour alternating with. Fortified Cefazolin 1 drop every hour. Fortified Vancomycin eye drops – reserved drug

Treatment 

The frequency of antibiotic administration should be tapered off parameters:    

Decreased density of infiltrate Decreased anterior chamber inflammation Reepithelialization of the corneal epithelial Improvement in pain

Corneal Ulcer, Bacterial, Under Treatment No longer hypopyon, thus indicating effective

Treatment 

Cycloplegic agents – atropine, Homatropine, Cyclopentolate Relieve ciliary spasm  Prevent synechiae 

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Oral pain medications Oral antibiotics – scleral expansion Repeated scraping

Complications       

Descematocele Perforation – iris prolapse Pseudocornea Secondary glaucoma Anterior capsular cataract Spontaneous expulsion of lens and vitreous Endophthalmitis

Descemetcele, Old

nter the tissue has melted away and a Descemetocele has d

Treatment of complicated ulcers 

Perforated ulcers –     

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Firmly applied bandage; Bandage contact lenses forced expiration avoided Tissue adhesives antiglaucomas Corneal transplant

Secondary glaucoma – iv mannitol/ Acetazolamide; Topical antiglaucomas Late management – Corneal grafts; Cosmetic CL; Tattoing

Perforated Corneal Ulcer, Keratoplasty