医学教学ppt课件:散光硬性角膜接触镜.ppt
1,散光硬性角膜接触镜,沈一温州医学院附属眼视光医院,散 光,眼的两条主子午线上度数不相等所导致的屈光不正。,GOOD,30-100,90-100,120-100,180-100,1-P50,1-P51,1-P52,1-P53,1-P54,散光,轴子午线,水平焦线,垂直焦线,最小弥散环,度数子午线,物体,A,B,D,C,Sturm间隙,1-D57,散光按散光大小分类的发病率*(Holden,1975),*无老视者,“K”41.00 180/42.50 90,41.00,42.50,顺规散光,对应于矫正镜片的轴子午线,位于 0 到 30,或 150 到 180,“K”42.50 180/41.00 90,42.50,41.00,逆规散光,对应于矫正镜片的轴子午线,位于 60 到 120,“K”41.00 135/42.50 45,42.50,41.00,斜轴散光,对应于矫正镜片的轴子午线,位于 31 到59,或者 121 到 149,8,不规则散光,“K”57.00 172/60.00 60,处方-7.00-3.50 x 16220/200,9,全眼散光,眼内散光,散光的种类,角膜散光,10,11,“K”47.1 74/44.1 164,处方-2.00/-3.00 x165,角膜散光,12,13,“K”43.90 67/43.60 157,处方-3.00-2.00 x 90,眼内/晶状体散光,14,残余散光,验光处方无或低散光,角膜高散光配戴球性RGP镜片完全矫正角膜散光,验光结果仍然存在的散光角膜散光和眼睛总散光的差值,15,RGP镜片矫正散光,球性RGP镜片环曲面RGP镜片前环曲面镜片:眼内散光后环曲面镜片:角膜散光双环曲面镜片:角膜散光和眼内散光并存,16,“K”41.00 180/42.50 90,Rx-3.50-1.50 x 180,RGP镜片选择,球性RGP,17,“K”42.00 180/45.50 90,处方-2.50-3.50 x 175,RGP镜片选择,后环曲面RGP,18,“K”45.50 180/46.00 90,处方-5.00-2.50 x 90,RGP镜片选择,前环曲面RGP,19,“K”42.50 180/45.50 90,处方+3.00-5.00 x 170,RGP镜片选择,双环曲面RGP,20,前环曲面RGP验配,试戴镜片的选择镜片评价戴镜验光轴向的确定确定处方定购镜片,21,前环曲面镜片,22,前环曲面镜片,最终 42.00-2.75-2.00 x 178 9.4,棱镜垂重,23,散光镜片,良好的矫正视力需要稳定的散光轴向定位,24,稳定方法,棱镜垂重法截边法周边垂重法,25,稳定方法,棱镜垂重,BOZD,26,定位标记的种类,180,180,180,30,20,27,LARS,28,后环曲面RGP,后环曲面RGP能矫正更多角膜散光更好的镜片与角膜的配适双环曲面RGP能同时解决眼内散光,29,球性RGP镜片,低至中等量角膜顺规散光配戴球性RGP镜片,为理想配适,30,如角膜散光过大,球性RGP验配后,存在明显的压迫和间隙区域,需要特殊设计的RGP镜片,31,45.00,42.00,垂直,水平,32,同样的角膜配戴基弧比较陡峭的镜片,垂直方向匹配更好,水平方向接触过多,33,给中、高度散光的角膜验配,镜片可以设计成后表面含两条独立的曲线。,内/后表面,45.00,42.00,34,球性RGP,不影响角膜 或舒适!,RGP镜片在瞬目时应当能够上下移动,42.00,43.00,42.00,43.00,42.00,43.00,42.00,RGP镜片不应产生横向运动,43.00,35,镜片不可以产生横向运动水平子午线应与水平“K”读数匹配,或稍微陡峭一些,后环曲面RGP,36,镜片需要自由纵向运动垂直子午线配适应稍平坦于垂直“K”读数,37,参数选择练习,38,“K”42.00 180/46.50 90,处方-3.004.50180,39,42.00 D,将水平“K”读数置于水平轴向上:42.00 180,-3.00 4.50180,40,46.50 D,将垂直“K”读数置于垂直轴向上:46.50 90,-3.00 4.50180,41,42.00 D,46.50 D,将球镜置于最平坦子午线上,-3.00 D,-3.00 4.50180,42,42.00 D-3.00 D,将联合度数置于最陡峭子午线上,46.50 D-7.50 D(vertexed to-6.75 D),-3.00 4.50180,43,42.00 D-3.00 D,46.50 D-6.75 D,将联合度数置于最陡峭子午线上,44,42.00 D-3.00 D42.00 D-3.00 D,46.50 D-6.75 D45.75 D-6.00 D,将联合度数置于最陡峭子午线上,当角膜散光大于4.00D时,陡峭子午线上的基弧要变平坦两基弧差值的1/51/6,屈光度相应改变,45,镜片标记,实际读数,42.00 D-3.00 D 9.2mm 45.75 D-6.00 D 9.2mm,46,THANKS!QUESTIONS?,