Patel Sanjay V, McLaren Jay W, Hodge David O, Bourne William M
Department of Ophthalmology, Mayo Clinic, Rochester, Minnesota 55905, USA.
Am J Ophthalmol. 2008 Dec;146(6):913-9. doi: 10.1016/j.ajo.2008.07.018. Epub 2008 Sep 6.
To determine the effect of corneal light scatter on vision after penetrating keratoplasty (PK).
Cross-sectional study.
setting: Cornea service at Mayo Clinic, Rochester, Minnesota. study population: Sixty-one eyes with clear grafts at 14.6 +/- 10.5 years after PK; 12 eyes with late endothelial failure (LEF) at 19.7 +/- 6.4 years after PK; 41 normal eyes. observation procedures: PK. main outcome measures: Backscatter from different depths of the cornea was measured by a custom scatterometer; intraocular forward light scatter was measured with a stray light meter; high-contrast visual acuity (HCVA) was measured by Early Treatment Diabetic Retinopathy Study (ETDRS) or Snellen chart; mesopic and photopic low-contrast visual acuity (LCVA) were measured with a 10% contrast chart.
Backscatter from the anterior, middle (stroma), and posterior thirds of the cornea was higher in clear grafts compared with normal (P < .001), and higher in grafts with LEF compared with clear grafts (P < .001). Corneal stromal backscatter from clear grafts correlated with time after keratoplasty (r = 0.21; P = .006; n = 61). Forward light scatter was higher in eyes with clear grafts compared with normal (P < or = .006), and higher in eyes with LEF compared with clear grafts (P < or = .01). Corneal stromal backscatter from clear grafts correlated with HCVA (r = 0.34; P = .02; n = 52), mesopic LCVA (r = 0.36; P = .01; n = 28), and photopic LCVA (r = 0.57; P < .001; n = 28). Forward scatter in eyes with clear grafts correlated with photopic LCVA (r = 0.38; P = .04; n = 26).
Light scattered from the cornea increases with time after PK and is associated with decreased high- and low-contrast vision.
确定穿透性角膜移植术（PK）后角膜光散射对视力的影响。
横断面研究。
地点：明尼苏达州罗切斯特市梅奥诊所角膜科。研究对象：61只在PK术后14.6±10.5年移植片透明的眼；12只在PK术后19.7±6.4年发生晚期内皮功能衰竭（LEF）的眼；41只正常眼。观察程序：PK。主要观察指标：用定制的散射仪测量角膜不同深度的后向散射；用杂散光仪测量眼内前向光散射；用糖尿病视网膜病变早期治疗研究（ETDRS）或斯内伦视力表测量高对比度视力（HCVA）；用10%对比度视力表测量中视和明视低对比度视力（LCVA）。
与正常眼相比，透明移植片角膜前、中（基质）和后三分之一的后向散射更高（P<.001），与透明移植片相比，发生LEF的移植片后向散射更高（P<.001）。透明移植片的角膜基质后向散射与角膜移植术后时间相关（r = 0.21；P = .006；n = 61）。与正常眼相比，透明移植片眼的前向光散射更高（P≤.006），与透明移植片眼相比，发生LEF的眼的前向光散射更高（P≤.01）。透明移植片的角膜基质后向散射与HCVA（r = 0.34；P = .02；n = 52）、中视LCVA（r = 0.36；P = .01；n = 28）和明视LCVA（r = 0.57；P<.001；n = 28）相关。透明移植片眼的前向散射与明视LCVA相关（r = 0.38；P = .04；n = 26）。
PK术后角膜散射光随时间增加，并与高对比度和低对比度视力下降相关。
