圆锥角膜胶原交联术后一年角膜生物力学变化及其与眼压的相关性

Correlation analysis between change of corneal biomechanical parameters and measurement of intraocular pressure after corneal collagen crosslinking for keratoconus

目的观察圆锥角膜患者角膜胶原交联术前后角膜生物力学变化及其与眼压的相关性。设计队列研究。研究对象23例圆锥角膜患者41眼。方法受试者于术前、术后1周及术后1、3、6、12个月进行验光,中央角膜厚度(CCT)、眼压(IOP)检查,用眼反应分析仪(ORA)测量角膜滞后量(CH)、角膜阻力因子(CRF)、模拟Goldmann眼压(IOPg)和角膜补偿眼压(IOPcc)。比较手术前后各参数的变化及与眼压测量值的相关性。主要指标视力、CCT、IOP、IOPg、IOPcc、CH、CRF。结果41眼圆锥角膜的CH术前为(8.044±1.264),角膜胶原交联术后1年下降到(7.817±1.561)(t=2.48,P=0.01)。CRF术前为(6.846±1.353),术后1年为(6.687±1.233)(t=-0.55,P=0.58)。角膜胶原交联术后1年时,非接触眼压与IOPg(r=0.724,P<0.001)、IOPcc(r=0.613,P<0.001)及CRF(r=0.513,P<0.001)均成正相关。结论圆锥角膜患者角膜胶原交联术后1年时CH值较术前下降,CRF值较术前无变化。NCT眼压与IOPg、IOPcc及CRF值存在中等强度的正相关关系,NCT眼压值的变化在一定程度上反映CRF值的变化。

Objective To describe the change of the corneal biomechanical parameter and intraocular pressure(IOP)for kerotoconus eyes before and after the collagen crosslinking procedure(CXL).Design Cohort study.Participants 23 cases of keratoconus(41 eyes).Method All patients undergo refractive examination,central corneal thickness(CCT),non-contact tonometer(NCT),and ocular response analyzer(ORA)before CXL surgery,and 1 week,1,3,6,and 12 months after CXL surgery.Corneal hysteresis(CH),corneal resistance factor(CRF),simulated Goldmann intraocular pressure(IOPg)and corneal compensated intraocular pressure(IOPcc)were measured with ORA.The changes of parameters before and after CXL surgery were compared and the correlation between the changes of corneal biomechanical parameters and IOP was analyzed.Main Outcome Measures Visual acuity,optometry,CCT,IOPcc,CH,CRF.Result The preoperative CH of the keratoconus of 41 eyes was 8.044±1.264,and it decreased to 7.817±1.561 1 year after operation,which was statistically different from that before operation(t=2.48,P=0.01).The preoperative CRF was 6.846±1.353,and the postoperative 1 year was 6.687±1.233,which was not statistically different from the preoperative(t=-0.55,P=0.58).At 1 year after CXL surgery,NCT IOP was positively correlated with IOPg(r=0.724,P<0.001),IOPcc(r=0.613,P<0.001),and CRF(r=0.513,P<0.001).Conclusion At 1 year after CXL surgery,the CH value decreased compared with preoperative,and the CRF value did not change compared with preoperative.There is a medium-intensity positive correlation between NCT intraocular pressure and IOPg,IOPcc and CRF values.The change in NCT intraocular pressure value,to some extent,can reflect the change of CRF value.