视光部分ICO复习课件

1、视光部份ICO复习相对调节负相对调节：能放松的调节，加正镜。正相对调节：能做出的最大调节量，加负镜。根据Hofstentters公式： 最小调节幅度15-0.25年龄 平均调节幅度18.5-0.3年龄 最大调节幅度25-0.4年龄Accommodationa) myopic patients may increase their myopic prescription and avoid the wear of reading glassesb) the near point of an emmetropic patient who has 5D of accommodative power

2、is 20cmc) in order to focus at an object placed at 20cm, a patient with myopia of -2.00D requires an accommodative power of 2Dd) myopia can be partially overcome by accommodatione) an emmetropic patient with 2D of accommodative power can read comfortably at 33cm without reading glasses球柱镜转化记住原则：球柱相加

3、为新球镜，柱镜度数不变，柱镜交换符号，轴位旋转90（大于90的减去90小于90的加上90。）顺归性散光（with the rule ，WR）：角膜高屈光力子午线位于垂直位（12060）逆规性散光（AR）：角膜高屈光力子午线位于水平位（15030）斜轴散光：角膜高屈光力子午线位于3060或是120150Jackson cross-cylindera) a -0.50D sphere is coupled with a -1.00D cylinderb) is useful in refining the spherical power during trial of lensc) the han

4、dle is mounted parallel to one of the axes of the cylindersd) when refining the power of a trial cylinder, the handle of the Jackson cross-cylinder is placed in line with the axis of the trial cylindere) a Jackson cross-cylinder designated 1.00D consists of a +1.00D cylinderTransposition of cylinder

5、sa)-4.00DS/-1.00DC170= -5.00DS/+1.00DC170b)+2.00 DS/+1.00DC150= +1.50DS/-1.00DC130c)-1.00 DS/+2.00DC100= +1.50DS/+1.00DC10d)-3.00 DS/+1.00DC150= -2.00DS/-1.00DC60e) -1.00 DS/-2.00DC180= +1.00DS/+2.00DC90立体视正常立体视觉60seconds or better，单位seconds,提示可能存在弱视：低于250seconds。立体视图谱检查： TNO：红绿眼镜 480-15 seconds TIM

6、US TEST（包括wirt fly）：偏振眼镜 3000-40 seconds FRISBY：不需眼镜 600-15seconds棱镜棱镜处方：内斜底朝外，外斜底朝内水平斜棱镜度分配到双眼，棱镜底朝向相同，上下斜棱镜分配到双眼时方向相反。光线折射后朝棱镜底部偏移，D偏移角=棱镜顶角/2在距离棱镜1m处，如果折射光线与入射光线发生偏折1cm，则为1棱镜度。1度等同于1.75棱镜度。 1棱镜度等同于0.5729度。 散光的轴采用的是0-180度，而棱镜采用0-360度。 计算球面透镜移心后的棱镜效果公式： PcF C:入射点到光心的距离 ，单位cm F：透镜的屈光度光谱UV-C 200-280n

7、m，UV-B 280-315,UV-A 315-400 可见光400-780nm Infrared A 780-1400nmInfrared B 1400-3000nmInfrared C 3000-10000nm色像差：应用于验光双色试验：确保近视者不过矫，对0.25D差别敏感，红绿色盲者也适用。原理：红波波长长折射率小，绿波的波长短折射率大，所以绿色背景上的视标所成的像较红色的所成的像更靠近角膜些。结果：红色背景清，应减少正镜（或增加负镜）；绿色清应增加正镜（或减少负镜），近视者绿清为过矫了。Duochrome testa) is useful in myopic patients to

8、avoid undercorrectionb) cannot be used in colour blind patientsc) is due to spherical aberration of the eyed) red light is refracted less than green lighte) at completion of duochrome test, green letters should be clearer than red letters检影中和点的判断：越接近中和光影越亮，运动越快，光带越大。马式杆：右眼放马式杆，杆在水平位成像为垂直的线条。 记住内同外交。（内斜线条与马式杆同侧，外斜交叉。） 远视患儿内斜内隐斜尽量足矫（放松调节），近视患儿外斜外隐斜（