Al-Tuwairqi Waleed S, Ogbuehi Kelechi C, Razzouk Haya, Alanazi Mana A, Osuagwu Uchechukwu L
Refractive Surgery Unit (W.S.A.-T., H.R.), Elite Medical & Surgical Center, Riyadh, Saudi Arabia; Department of Medicine (K.C.O.), Dunedin School of Medicine, University of Otago, Dunedin, New Zealand; Department of Optometry and Vision Sciences (M.A.A.), College of Applied Medical Sciences, King Saud University, Riyadh, Saudi Arabia; and Institute of Health and Biomedical Innovation (U.L.O.), Chronic Disease and Ageing, Department of Optometry and Vision Sciences, Queensland University of Technology, Brisbane, Queensland, Australia.
Eye Contact Lens. 2017 Mar;43(2):116-122. doi: 10.1097/ICL.0000000000000244.
To assess the agreement between subjective refraction and autorefraction and to explore the relationship between the magnitude of higher order aberration, and visual acuity and refraction, before and after keraring implantation.
This prospective, randomized, interventional study enrolled 27 subjects (mean age 28.1±6.5 years) with keratoconus. Noncycloplegic refraction was performed subjectively by one clinician and with an autorefractor by another clinician, before and 6 months after surgery. The limit of agreement (LoA) between methods was assessed, and the relationships between the corrected distance visual acuity, logMAR on the one hand and refraction measurements and higher-order aberrations on the other, were examined.
The agreement in mean spherical equivalent refraction (MSER) between methods was good postoperatively but poor preoperatively. The autorefractor gave a more myopic refraction than subjective refraction preoperatively (-3.28±3.06 D; LoA -9.27 to +2.71 D, P<0.0001) and postoperatively (-0.63±1.64 D; LoA -3.85 to +2.58 D, P=0.055), and returned higher negative cylinders preoperatively (-1.10±1.17 D; LoA -3.40 to +1.19 D, P<0.0001) and postoperatively (-1.08±1.27 D; LoA -3.60 to +1.41 D, P<0.0001) in keratoconic eyes. The difference in MSER between methods was significantly related to the refractive error at both visits (P<0.05) and to the magnitude of higher-order aberrations in keratoconic eyes preoperatively (P<0.05). The logMAR visual acuity achieved subjectively worsened as the magnitude of higher-order aberrations increased preoperatively (P<0.001).
The autorefractor returns values that are significantly more myopic in MSER and higher negative cylinders than subjective refraction, preoperatively, but the MSER was similar between devices postoperatively. The autorefactor seems a valid starting point for subjective refraction in keratoconic eyes treated with keraring, but the cylinder should be corrected by about +1 D. The instruments agree more in less myopic than high myopic eyes.
评估主观验光与自动验光之间的一致性，并探讨角膜基质环植入术前、后高阶像差大小与视力及屈光不正之间的关系。
这项前瞻性、随机、干预性研究纳入了27例圆锥角膜患者（平均年龄28.1±6.5岁）。手术前和术后6个月，由一名临床医生进行主观非散瞳验光，另一名临床医生使用自动验光仪验光。评估两种方法之间的一致性界限（LoA），并检查矫正远视力（logMAR）与屈光测量值和高阶像差之间的关系。
两种方法之间平均球镜等效屈光力（MSER）的一致性在术后良好，但术前较差。术前自动验光仪给出的屈光度数比主观验光更近视（-3.28±3.06 D；LoA -9.27至+2.71 D，P<0.0001），术后也是如此（-0.63±1.64 D；LoA -3.85至+2.58 D，P=0.055），并且术前（-1.10±1.17 D；LoA -3.40至+1.19 D，P<0.0001）和术后（-1.08±1.27 D；LoA -3.60至+1.41 D，P<0.0001）圆锥角膜眼中自动验光仪给出的负柱镜度数更高。两种方法之间MSER的差异在两次检查时均与屈光不正显著相关（P<0.05），并且术前与圆锥角膜眼中高阶像差的大小显著相关（P<0.05）。术前随着高阶像差大小增加，主观获得的logMAR视力变差（P<0.001）。
术前自动验光仪给出的MSER值比主观验光明显更近视，负柱镜度数更高，但术后两种设备的MSER相似。对于接受角膜基质环治疗的圆锥角膜眼，自动验光仪似乎是主观验光的一个有效起点，但柱镜度数应矫正约+1 D。在近视程度较低的眼中，两种仪器的一致性比高度近视眼中更好。
