摘要:
Objective To study the effects of ultraviolet light combined with riboflavin treatment (corneal collagen-crosslinking, CXL) on infectious control and stromal reconstruction of bacterial keratitis. Methods Experimental Study. A Staphylococcus aureus rabbit keratitis model was established by injecting Staphylococcus aureus broth into the shallow stromal layer of the right eye cornea of New Zealand white rabbits. Forty-four rabbits that successfully established the model were randomly divided into four groups:corneal collagen cross-linking (CXL) group, antibiotic group, CXL+ antibiotic group and untreated group, with 11 rabbits in each group. Before the treatment and at 3, 7, 14 and 28 days after treatment, slit lamp corneal examination, AS-OCT and in vivo confocal microscopy (IVCM) were performed. Clinical efficacy of different treatments were evaluated at different time points. Parameters including conjunctival hyperemia, corneal ulcer, infiltration, edema, and neovascular. Histopathological examinations of corneal lesions were performed in order to detect the infiltration, inflammatory cells and repair in corneal tissue. Normal data were compared with paired t-test and non-normal data were compared with paired rank sum test before and after treatment. Kruskal-Wallis rank sum test was used to compare 4 groups of data and the generalized estimation equation is used to compare the repeated measurement data at each time point and the comparison between the groups of the treatment groups. Results After treatment, different time points and specimens for pathological observation, we obtained the following results:Conjunctival hyperemia: in CXL and CXL+antibiotic groups after treatment for 3 days from treatment before 3 (2,-4) and 3 (2,-3),The reduction was 2 (1,-3) and 2 (1,-2), the difference was statistically significant (Z=-3.91,-5.50;P0.008).治疗14 d后CXL组和CXL+抗生素组角膜溃疡面积(0.08±0.05)、(0.07±0.05)cm2较治疗前(0.40±0.18)、(0.49±0.24)cm2明显减小,差异有统计学意义(Z=-3.29,-3.64;P<0.008);治疗14 d后,CXL组和CXL+抗生素组新生血管开始消退,由治疗7 d时的1(1,-2)和1(0,-2)级减少至1(1,-1)和0(0,-1)级,差异有统计学意义(Z=4.57,3.80;P<0.0125).CXL组、CXL+抗生素组在治疗后14 d,角膜水肿程度明显减轻,由治疗前的(650±154)、(785±255)μm减轻到14 d时的(432±95)、(455±109)μm,差异有统计学意义(t=4.50,4.92;P=0.00).角膜基质炎症细胞密度也由(446±257)、(321±145)个/mm2,减少至(107±66)、(114±94)个/mm2,差异有统计学意义(t=4.15,4.76;P<0.05).光学显微镜下组织病理学观察CXL组、CXL+抗生素组在治疗7 d时,角膜溃疡大部分愈合,上皮细胞清晰可见、排列不齐,基质层少量中性粒细胞;治疗14 d上皮层完整,基质细胞排列整齐、结构清晰,炎症细胞明显减少.结论 紫外线联合核黄素角膜胶原交联术对兔细菌性角膜炎感染控制、溃疡修复具有一定的治疗作用,可作为抗生素治疗的辅助手段.