目的：评估带蒂角膜上皮瓣下等渗核黄素及恢复上皮瓣的快速角膜胶原交联术(A-CXL)治疗过薄圆锥角膜(去上皮后角膜厚度小于400 μm)患者的疗效和安全性。

方法：回顾性研究。纳入2017-09/2020-12于成都中医大银海眼科医院屈光手术科治疗圆锥角膜患者46例74眼。根据术前最薄点角膜厚度(TCT)分为两组： TCT为400-<450 μm的患者行带蒂角膜上皮瓣下等渗核黄素及恢复上皮瓣A-CXL 16例20眼，手术方法为做带蒂角膜上皮瓣并掀开，等渗核黄素滴眼，将角膜上皮瓣重新恢复后，进行紫外线照射，照射结束后，刮除角膜上皮瓣。TCT≥450 μm的患者行去上皮A-CXL手术30例54眼。随访12 mo，收集所有患者手术前后最佳矫正视力(BCVA)、Sirius三维角膜地形图、角膜内皮细胞密度检查结果。

结果：术后12 mo，带蒂角膜上皮瓣A-CXL组患者Kmax较术前无差异(P>0.005)，去上皮A-CXL组患者Kmax较术前显著降低(P<0.005)。两组术后12 mo BCVA(LogMAR)、角膜前后表面曲率(K1、K2)及角膜内皮细胞密度较术前均无差异(均P>0.005)。两组各指标术后12 mo与术前变化量比较均无差异(均P>0.05)。

结论： 带蒂角膜上皮瓣下等渗核黄素及恢复上皮瓣A-CXL对于TCT为400-<450 μm圆锥角膜患者安全可行，与去上皮A-CXL手术控制圆锥角膜进展的趋势相似。

METHODS: Retrospective study. A total of 46 patients(74 eyes)with keratoconus treated in the refractive surgery department of Ineye Hospital of Chengdu University of TCM from September 2017 to December 2020 were enrolled. According to the preoperative thinnest corneal thickness(TCT), the patients were divided into two groups: 16 patients(20 eyes)with TCT ranging from 400 to <450 μm underwent accelerated corneal cross-linking with application of isotonic riboflavin under pedicled corneal epithelial flap, and the surgical method involves creating a pedicled corneal epithelial flap and lifting it, applying isotonic riboflavin eye drops, repositioning the corneal epithelial flap, performing ultraviolet irradiation and then using corettage of corneal epithlial flap after irradiation. Another 30 patients(54 eyes)with TCT ≥450 μm underwent epithelial-off A-CXL surgery. After follow-up for 12 mo, the results of best corrected visual acuity(BCVA), Sirius three-dimensional corneal topography, and corneal endothelial cell density were collected before and after surgery.

RESULTS: At 12 months post-surgery, patients in the pedicled corneal epithelial flap group showed no significant difference in Kmax compared with pre-surgery(P>0.005), while patients in the epithelial-off group showed a significant reduction in Kmax compared with pre-surgery(P<0.005). For both groups, there were no significant differences in BCVA(LogMAR), corneal anterior and posterior surface curvatures(K1, K2), and corneal endothelial cell density at 12 mo post-surgery compared with pre-surgery(all P>0.005). The comparisons of the changes in various parameters between 12 mo post-surgery and pre-surgery for both groups showed no significant differences(all P>0.05).

CONCLUSION: Accelerated corneal cross-linking with application of isotonic riboflavin under pedicled corneal epithelial flap surgery is safe and feasible for patients with thin keratoconus, achieving similar control of keratoconus progression as epithelial-off A-CXL.