评价SMILE术后视觉质量与光学调制传递函数的关系

Evaluation of the relationship between visual quality and optical modulation transfer function after SMILE

目的:探讨飞秒激光小切口角膜基质透镜取出术(SMILE)术后光学调制度传递函数(MTF)特点,并探究术后裸眼视力(UCVA)、对比敏感度功能(CSF)与MTF的关系。方法:横断面选取2015-06/11在天津市眼科医院行SMILE手术矫正近视患者34例68眼,术后眼部情况稳定3mo以上且术后残余屈光度均小于±0.50D。在明视觉下,用国际标准视力表测量UCVA,用CSV-1000E测量CSF。用WaveScan测量全眼的波前像差,经Matlab编程,将像差进行公式转换成MTF,取3、6、12、18c/d四频区结果进行统计。结果:在3、6、12、18c/d频区,CSF值分别为:63.19±3.18、110.25±5.22、57.65±3.76、16.15±1.04;MTF值分别为:0.80±0.02、0.56±0.03、0.30±0.02、0.19±0.02。在6、12、18c/d频区,UCVA与CSF具有相关性(r=0.548、0.337、0.324,P<0.01、=0.005、0.007);而在18c/d频区,CSF与MTF具有相关性(r=0.241,P=0.048)。结论:SMILE手术矫正后光学质量(MTF)的变化规律不同于视觉质量的变化规律,不同于视力和对比敏感度,虽然屈光系统发生像差等变化,但最终手术对全眼CSF无影响,说明视神经大脑通路对视觉质量具有补偿作用。计算MTF对评价手术后光学质量的判断具有一定的理论和临床应用价值。

·AIM:To investigate the characteristics of optical modulation transfer function(MTF)of the eyes after femtosecond laser small incision lenticule extraction(SMILE),and to evaluate the relationship between visual acuity(VA),contrast sensitivity(CSF)and MTF.·METHODS:From June to November,2015,34 myopia patients(68 eyes)who underwent SMILE surgery in Tianjin Eye Hospital were selected in cross-section.The posoperative eye condition was stable for more than 3mo after surgery.The residual diopter of the eyes after SMILE was less than±0.50D.Under bright vision,measured VA by International standard visual acuity chart and CSF by CSV-1000E.The wavefront aberration of the whole eyes were measured by WaveScan,and MTF of the eyes were obtained by using aberration formula conversion and Matlab programming.The MTF of(3,6,12,18)c/d frequency region were counted.·RESULTS:CSF values in 3,6,12,18 c/d frequency range were 63.19±3.18,110.25±5.22,57.65±3.76,16.15±1.04;MTF values in 3,6,12,18 c/d frequency range were 0.80±0.02,0.56±0.03,0.30±0.02,0.19±0.02.In 6,12,18 c/d frequency range,visual acuity was significantly correlated with CSF(r=0.548,0.337,0.324,P<0.01,=0.005,0.007).In 18c/d frequency range,CSF was significantly correlated with MTF(r=0.241,P=0.048).·CONCLUSION:The change of optical quality(MTF)after SMILE was different from that of visual quality(visual acuity and contrast sensitivity).Although the aberration of refractive system changed,the SMILE surgery had no effect on CSF,which indicated that neuro-brain had a compensatory effect on visual quality.Computational MTF has certain theoretical and clinical value in evaluating the optical quality after refractive surgery.