كليدواژه :
Chronic , delayed , چشم پزشكي , استان تهران , كم بينايي , Mustard gas , keratitis , نابينايي
چكيده لاتين :
Purpose: To report the clinical features of 93 eyes with chronic and delayed onset mustard gas keratitis in 48 patients.
Methods: Forty-eight Iranian survivors of Iraqi chemical warfare with chronic or delayed onset mustard gas keratitis were enrolled. We reviewed the symptoms, signs, clinical course, and treatment of our patients. In 5 cases, histopathologic features of corneal and conjunctival specimens are presented.
Results: Of 48 patients, 31 (64.6%) had chronic symptomatology whereas 17 (35.4%) experienced delayed onset lesions. Visual acuity at referral ranged from hand motions to 20120. Ocular surface changes included chronic blepharitis and decreased tear meniscus in all, timbal ischemia (81.3%) and conjunctival vascular abnormalities (50%). Corneal signs in order of frequency were: scarlopacity (87.5%), neovascularization (70.8%), thinning (58.3%), lipoid deposits (52.1%), amyloid deposits (43.8%), and epithelial defects and irregularity (31.3%). Twenty patients received conservative treatment; others underwent allograft stem cell transplantation (20 eyes of 17 patients), penetrating keratoplasty (12 eyes of 12 patients), and lamellar keratoplasty (4 eyes of 3 patients). Conjunctival specimens were evaluated by light microscopy. Decreased goblet cell density, attenuated or thickened epithelium, scarring in the substantia propria associated with plasmacytic and lymphocytic infiltration, and dilated lymphatic vessels were noted. Excised corneal buttons disclosed absence of epithelium and Bowmanʹs layer, firbrovascular pannus, stromal scarring, and vascularization.
Conclusion: Mustard gas may cause chronic and delayed destructive lesions in the ocular surface and cornea leading to progressive visual deterioration and ocular irritation. The pathophysiology of these changes is not clearly identified. Excised conjunctival and corneal specimens revealed a mixed inflammatory response without any specific features. Based on the clinical appearance of the lesions and histopathologic findings, an immune-mediated component seems possible.
