Agrawal Nisha, Singh S K
Nepal J Ophthalmol. 2016 Jan;8(15):47-53. doi: 10.3126/nepjoph.v8i1.16156.
Corneal ulcer is a leading cause of blindness worldwide. Many of these patients don't respond to conventional treatment with topical agents. Collagen cross-linking (CXL) has been suggested to avoid complications requiring emergency keratoplasty.
Six eyes with presumed bacterial keratitis not responding to conventional treatment underwent CXL with ultraviolet A rays and transepithelial riboflavin. Patients with Descematocele and perforated ulcers were excluded. Preoperatively and postoperatively slit lamp examination of cornea and visual acuity recording was done. Postoperative outcome included subjective symptoms like relief in pain, photophobia, lacrimation and objective signs like improvement in epithelisation, corneal scarring with vascularisation.
Four of the six eyes healed completely with scarring at 2 months follow-up. One of the patients developed Descematocele on 12 days which perforated later. Other patient developed Descematocele on 20 days post CXL. Of the subjective symptoms, pain and epiphora improved in all the patients except one. Photophobia improved only a week after CXL in four out of six patients. Epithelial defect completely healed over time in four out of six cases. All the cases who responded to treatment developed superficial and deep vascularisation of the cornea. Decrease in corneal edema and scarring was noted in four out of the six cases.
The collagen cross-linking has a beneficial role as an adjuvant to medical therapy in recalcitrant bacterial keratitis. It helps in relief of pain and healing of ulcer. Larger randomized control trails with longer follow-up are required to come to a definite conclusion.
角膜溃疡是全球失明的主要原因之一。许多此类患者对局部用药的传统治疗无反应。有人提出胶原交联（CXL）可避免需要紧急角膜移植术的并发症。
6例疑似细菌性角膜炎且对传统治疗无反应的患者接受了紫外线A光和经上皮核黄素的胶原交联治疗。排除了有角膜后弹力层膨出和穿孔性溃疡的患者。术前和术后进行角膜裂隙灯检查并记录视力。术后结果包括主观症状（如疼痛、畏光、流泪缓解）和客观体征（如上皮化改善、角膜瘢痕伴血管化）。
6只眼中有4只在2个月随访时完全愈合并形成瘢痕。1例患者在第12天出现角膜后弹力层膨出，随后穿孔。另1例患者在胶原交联治疗后第20天出现角膜后弹力层膨出。在主观症状方面，除1例患者外，所有患者的疼痛和溢泪均有所改善。6例患者中有4例在胶原交联治疗1周后畏光症状有所改善。6例中有4例的上皮缺损随时间完全愈合。所有对治疗有反应的病例均出现角膜浅层和深层血管化。6例中有4例角膜水肿和瘢痕减轻。
胶原交联作为顽固性细菌性角膜炎药物治疗的辅助手段具有有益作用。它有助于缓解疼痛和溃疡愈合。需要进行更大规模、随访时间更长的随机对照试验才能得出明确结论。
