01/03/2023
's ulcer
Mooren ulcer is a rare autoimmune disease characterized by progressive circumferential peripheral stromal ulceration with later central spread. There are two forms: the first affects mainly older patients, often in only one eye and usually responds well to medical therapy.
The second is more aggressive and likely to need systemic immunosuppression, carries a poorer prognosis, may be bilateral and associated with severe pain and tends to occur in younger patients, including widespread reports in men from the Indian subcontinent.
In at least some (usually milder) cases, there is a precipitating corneal insult such as surgery or infection.
Associated systemic autoimmune disease and corneal infection should always be ruled out.
Diagnosis
• Symptoms. Pain is prominent and may be severe. There is photophobia and blurred vision.
• Signs
○ Peripheral ulceration involving the superficial one-third of the stroma , with variable epithelial loss. Several distinct foci may be present and subsequently coalesce.
○ An undermined and infiltrated leading edge is characteristic .
○ Limbitis may be present, but not scleritis, which aids in distinguishing from systemic disease-associated PUK.
○ Progressive circumferential and central stromal thinning .
○ Vascularization involving the bed of the ulcer up to its leading edge but not beyond.
○ The healing stage is characterized by thinning, vascularization and scarring .
○ Iritis is not uncommon.
• Complications include severe astigmatism, perforation following minor trauma (spontaneous perforation is rare), secondary bacterial infection, cataract and glaucoma.
Treatment
• Topical steroids as frequently as hourly are combined with a low-frequency prophylactic topical antibiotic. If an effective response is seen, treatment is tapered over several months.
• Topical ciclosporin (up to 2%) may be effective, but can take weeks to exert a significant effect.
• Tacrolimus 0.1% ointment is effective in controlling refractory cases.
• Adjunctive topical therapy includes artificial tears and collagenase inhibitors such as acetylcysteine 10–20%.
• Conjunctival resection, which may be combined with excision of necrotic tissue, is performed if there is no response to topical steroids.
The excised area should extend 4 mm back from the limbus and 2 mm beyond the circumferential margins. Keratoepithelioplasty (suturing of a donor corneal lenticule onto the scleral bed) may be combined to produce a physical barrier against conjunctival regrowth and further melting. Steroids are continued postoperatively.
• Systemic immunosuppression may be needed, including steroids for rapid effect and should be instituted earlier for bilateral disease, or if involvement is advanced at first examination. Biological blockers show some promise.
• Systemic collagenase inhibitors such as doxycycline may be beneficial.
• Lamellar keratectomy involving dissection of the residual central island in advanced disease may remove the stimulus for further inflammation.
• Perforations. Management is as discussed earlier in this chapter.
• Visual rehabilitation. Keratoplasty (with immunosuppressive cover) may be considered once inflammation has settled.
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