魏升升李勇李晶刘建国叶璐万雅群李娟杜婧DOI:10.3760/cma.j.issn.0412-4081.2016.作者单位:710004陕西省西安市,西安市第四医院眼科激光视力矫正中心通信作者:刘建国,Email:drljg@163.com【摘要】目的探讨圆锥角膜患者的角膜生物力学改变特点及角膜生物力学眼压分析仪CorvisST在圆锥角膜诊断中的价值。
方法病例对照研究。选取圆锥角膜患者32例(41只眼)作为圆锥角膜组,健康角膜人群41例(41只眼)作为对照组。
应用角膜生物力学眼压分析仪CorvisST对两组人群角膜的第一次压平宽度(1stAlength)、第二次压平宽度(2stAlength)、第一次压平时速率(Vin)、第二次压平时速率(Vout)、最大变形幅度(Def.Ampl)、顶点距离(P.Dist)和曲率半径(Radius)等进行测量,两组生物力学参数之间采用单因素方差分析进行对比分析,生物力学参数与角膜形态学参数之间采用Pearson或Spearman相关性分析,绘制生物力学参数的受试者工作特征曲线(ROC)。
结果在圆锥角膜组中,Vin、Vout和Def.Ampl分别为(0.201±0.268)m/s、(0.463±0.121)m/s和(1.146±0.113)mm,明显高于对照组的(0.151±0.017)m/s、(0.418±0.060)m/s和(1.146±0.113)mm,差异有统计学意义(F=6.02
8,20.72
4,10.606;P<0.05)。
圆锥角膜组中的Radius为(5.898±0.976)mm,与健康角膜组的(7.012±0.728)mm相比明显减小,差异有明显统计学意义(F=5.27
7,P=0.02
3)。圆锥角膜组的1stAlength、Vout、Def.Ampl和Radius与角膜最薄点厚度之间具有明显相关性(r=0.330,-0.490,-0.48
2,0.676;
P=0.03
5,0.001,0.001,0.000),Def.Ampl和Radius与角膜前表面曲率Km之间具有明显的相关性(r=0.75
1,-0.528;P=0.04
4,0.019)。
Vin、Vout、Def.Ampl和Radius与后表面最大高度之间均具有明显的相关性(r=0.47
5,-0.55
2,-0.399,0.273;
P=0.021,0.015,0.001,0.000)。
Radius、Def.Ampl、Vout和Vin的ROC下面积均0.9。
结论圆锥角膜的Vin、Vout、Def.Ampl和Radius较健康角膜均有明显的改变,其中Radius对于角膜生物力学变化具有较高的敏感性,在圆锥角膜的诊断中应有较大的参考价值。
(中华眼科杂志,2016,52:)【关键词】圆锥角膜;角膜;生物力学;眼压测量法基金项目:陕西省社会发展攻关项目(2016SF-274)(2013K14-02-18);西安市社会发展引导项目SF1315(3);
陕西省卫生厅科技攻关课题(2014D49)CornealbiomechanicalpropertiesinkeratoconicandnormaleyesWeiShengsheng,LiYong,LiJing,LiuJianguo,YeLu,WanYaqun,LiJuan,DuJing.
Xi’anFourthHospital,Xi’an710004,China【Abstract】ObjectiveTocomparethecornealbiomechanicalpropertiesofkeratoconicandnormaleyes,andtoexplorethechangingcharacteristicsinkeratoconiceyes.MethodsCase-controlstudy.Thirty-twokeratoconicsubjects(41eyes)and41subjects(41eyes)withnormalcorneawereenrolledinthisstudy.Scheimpflugnoncontacttonometry(CorvisST)wasperformedtomeasurethelengthofAppl1(1stAlength),velocityofAppl1(Vin),lengthofAppl2(2ndAlength),velocityofAppl2(Vout),deformationamplitude(DA),peakdistance,andradius.ComparisonofthebiomechanicalpropertyvaluesbetweenthekeratoconicandnormaleyeswasperformedusingOne-WayANOVA.PearsonorSpearmancorrelationswereusedtoevaluatetherelationshipbetweencornealbiomechanicalpropertiesandcornealmorphologyparameters.TheareasunderROCcurvesofthebiomechanicalpropertiesofCorvisSTwerecalculated.
ResultsInthekeratoconicgroup,thevaluesofVin,Vout,andDAwere(0.201±0.268)m/s、(0.463±0.121)m/sand(1.146±0.113)mm,respectively,whichwereobviouslygreaterthanthenormalgroup(0.151±0.017)m/s、(0.418±0.060)m/sand(1.146±0.113)mm,respectively),therewassignificantdifference(F=6.02
8,20.72
4,10.606,P=0.016,0.000,0.001).Theradiusinthekeratoconiceyes(5.898±0.976)mmwasapparentlyshorterthanthenormaleyes(7.012±0.728)mm,andthedifferencewassignificant(F=5.27
7,P=0.023).Inthekeratoconiceyes,thereweresignificantcorrelationsbetween1stAlength,Vout.DA,radiusandthethicknessofthinnestcornea(r=0.330,-0.490,-0.48
2,0.67
6,P=0.03
5,0.001,0.001,0.000).ThereweresignificantcorrelationsbetweenDA,radiusandtheanteriorsurfacerefractivepowerKm(r=0.75
1,-0.52
8,P=0.04
4,0.019).Vin,Vout,DA,andradiushadstatisticallysignificantcorrelationswithmaximumposteriorsurfaceelevation(r=0.47
5,-0.55
2,-0.399,0.27
3,P=0.02
1,0.015,0.001,0.000).TheareasunderROCcurvesoftheradius,DA,Vout,andVinwereallgreaterthan0.9.ConclusionsTherewereobviouschangesofcornealbiomechanicalpropertiesinkeratoconiceyescomparedwithnormaleyes.Radiusshowedabettersensitivityforthechangeofcornealbiomechanicalpropertiesandamajorreferencevalueforthediagnosisofkeratoconus.(ChinJOphthalmol,2016,52:)【Keywords】:Keratoconus;Cornea;Biomechanics;
TonometryFundprogram:Socialdevelopmentprojectsofshaanxiprovince(2016SF-274)(2013K14-02-18);
XiansocialdevelopmentprojectsSF1315(3);
Shaanxiprovincialhealthofficeofscienceandtechnologyproject(2014D49)圆锥角膜是一种以角膜扩张为特征,致角膜中央部向前凸出呈圆锥形及产生高度不规则近视散光和不同视力损害的原发性角膜变性疾病。
国外流行病学调查资料显示,圆锥角膜的患病率为0.05%~0.23%。角膜地形图是目前临床诊断圆锥角膜的主要工具,可以较早发现角膜形态学的改变。
以往的研究发现,圆锥角膜发生锥形改变的同时,角膜基质胶原纤维组织结构和角膜的力学特性也在发生改变,Medeiros等应用眼反应分析仪(ocularresponseanalyser,ORA)对角膜的生物力学进行测量,发现圆锥角膜的角膜滞后量(cornealhysteresis,CH)与角膜阻力因子(cornealresistancefactor,CRF)均低于健康角膜。
最近出现的角膜生物力学眼压分析仪CorvisST采用超高速Scheimpflug扫描技术,可以直观的展现角膜的动态变化过程,并反映角膜生物力学改变的情况。
本文采用CorvisST对圆锥角膜和健康角膜
标签:角膜,生物力学,圆锥