Technolas217z准分子激光不同程序切削形态学分析

Comparative study of ablation profiles in four different formulations of Technolas 217z Excimer Laser

目的探讨Technolas217z准分子激光标准化切削，非球面切削，组织节约程序，以及波面像差引导的个体化切削程序形态学差异分析。方法应用Technolas217z准分子激光分别采用标准化切削，组织节约程序，非球面切削以及波面相差引导切削程序在博士伦激光能量测试板上进行-4Ds的球镜和-2DS／-1DCxl80度的球柱镜，光学区为6mm的测试，蔡司裂隙灯数码成像系统照相，测量四种程序下测试形态总光学区和有效光学区横径和垂直径，并分别计算其面积大小，比较其形态学差异。结果对于-4DS的球镜切削，四种切削方式测试形态均呈近圆形，标准化切削，非球面切削，组织节约程序和波面像差引导的切削程序的总光学区的直径大小依次分别为9．5mm、9．0mm、8．3mm和8．0mm；有效光学区的大小依次分别为：6．2mm、6．2mm、5．6mm和5．5mm；总光学区面积大小依次分别为73．80mm^2,67．42mm^2、62．88mm^2和58．65mm^2；有效光学区面积的大小依次分别为37．94mm236．78mm^2、29-31mm^2和28．27mm^2。对于-2DS／-1DC×180度的球柱镜切削，标准化切削形态呈椭圆形，其它三种切削方式测试形态均呈近圆形，标准化切削，非球面切削，组织节约程序和波面像差引导的切削程序的总光学区的面积大小依次分别为146．61mm^2、103．51mm^2．88．59mm^2和83．66mm^2有效光学区面积大小依次分别为56．65mm^2,50．07mm^2、36．23mm^2和45．82mm^2。结论四种切削程序相比较，标准化切削具有最大的光学区和过渡区，实际光学区还略大于理论值；尽管组织节约程序切削组织少，波面像差引导的切削能够降低手术前业已存在的高阶像差，但此二者有效光学区和过渡区均较理论值略小，采用此类程序一定要将光学区开大；非球面切削程序理论值与实际值一致，有效光学区大小与标准化切削基本一致，且能够减少切削本身带来的高阶像差，在临床上有重要意义。

Objective To compare the ablation profiles of four different formality for Technolas 217z Excimer Laser.Methods A standard spherical myopic photoablation of-4DS and a spherocylindrical myopic photoablation of-2DSx-1DCx180° with 6mm optical zone ablations were programmed into Technolas 217z excimer laser by four different formulations：planoscan, aspheric, tissue saving and wavefront-guided ablation in Bausch ＆ Lomb fluencetest plates.The fluencetest plates were photographed by VISUPAC 450 digital camera which amounted in ZEISS SL 130 slit-lamp system.The diameters,areas of each ablation profile were calculated by the software.Results For -4DS spherical myopic photoablation, the total diameters in the four patterns were 9.5mm,9.0mm.,8.3mm and 8.0mm respectively;The optical zone diameters were 6.2mm,6.2mm,5.6mm and 5.5mm respectively.The total areas of the four ablation patterns were 73.80mm^2,67.42 mm^2,62.88 mm^2 and 58.65 mm^2;The central areas were 37.94 mm^2,36.78 mm^2,29.31 mm^2 and 28.27 mm^2 respectively.For -2DS/-1DCx180° spherocylindrical myopic photoablation,the profile of standand ablation was ovoidal shape and the other three balations were nearly circular profiles.The total areas of the four ablation patterns were 146.61 mm^2, 103.51 mm^2,88.59 mm^2 and 83.66 mm^2 .The central areas were 56.65 mm^2, 50.07 mm^2, 36.23 mm^2 and 45.82 mm^2 respectively.Conclusion Planoscan ablation has the biggest optical zone,followed by aspheric,tissue saving and wavefront-guided ablation.It should give larger optical zones in tissue saving and wavefront-guided ablation because the optical zones were a little smaller than the theories.The aspherical ablation was prefered due to large optical zone and less high order aberration.