Long-term Outcomes of Penetrating Keratoplasty in Chronic and Delayed Mustard Gas Keratitis

PURPOSE:To report the long-term outcomes of penetrating keratoplasty (PKP) in war victims with chronic and delayed mustard gas keratitis. METHODS:This noncomparative interventional case series includes patients with advanced chronic or delayed mustard gas keratitis who had undergone PKP from 1989 to 2006. Best-corrected visual acuity (BCVA), graft clarity, episodes of graft rejection, duration of steroid use, and complications were evaluated. Histopathologic features of excised corneal buttons were also evaluated. RESULTS:Overall, 22 eyes of 19 patients underwent PKP. Mean age at the time of surgery was 41 ± 4.6 years (range, 36-54 years), and mean follow-up duration was 40.9 ± 48 months (range, 4-204 months). The graft remained clear in 17 (77.3%) eyes and failed in 5 (22.7%) eyes. Overall, 13 (59.1%) eyes experienced episodes of endothelial rejection, and 5 (22.7%) eyes had subepithelial immune rejection, 4 of which had simultaneous endothelial rejection. Fifteen (68.2%) eyes received topical steroids for >6 months. Fourteen (63.6%) eyes developed cataracts, leading to cataract extraction in 7 eyes. One eye developed steroid-induced glaucoma after multiple episodes of endothelial graft rejections. Mean preoperative BCVA was 1.92 ± 0.63 logMAR, which improved to 1.04 ± 0.65 logMAR (20/200) overall and 0.8 ± 0.3 logMAR (20/120) in eyes with clear grafts (P < 0.001). Main histopathologic features of excised corneal buttons included corneal thinning and ulceration, loss of keratocytes, acute and chronic inflammation, stromal vascularization, and degenerative sequelae of long-standing inflammation. CONCLUSIONS:PKP in chronic or delayed-onset mustard gas keratitis should be considered as a high-risk graft; however, with appropriate management, graft clarity and visual outcomes may be favorable.