Sehi M, Flanagan J G
School of Optometry, University of Waterloo, Waterloo, Ontario, Canada N2L 3G1.
Br J Ophthalmol. 2004 Feb;88(2):204-6. doi: 10.1136/bjo.2003.020321.
To examine the influence of image alignment on the repeatability of blood flow measurements of the optic nerve.
10 normal subjects were examined. Heidelberg retina tomograph imaging was performed to establish best location and focus for the temporal neuroretinal rim. Two high quality Heidelberg retina flowmeter (HRF) images were acquired for three methods of alignment: central, nasal, and temporal. A 10 x 10 pixel measurement window was selected and exactly reproduced on all images. The interquartile pixel values were used to calculate capillary flow. ANOVA, intraclass correlation coefficients (ICC) and the coefficient of repeatability (CoR) were used for analysis.
There was no difference between methods (p = 0.47) or between visits (p = 0.51). The ICCs were 0.83 for the central, 0.34 for the nasal, and 0.42 for the temporal alignment. The CoR was 31.5 for central (mean effect 235.1), 234.6 for nasal, and 256.7 for temporal alignment.
Central alignment was the most repeatable method for the measurement of neuroretinal rim capillary blood flow using the HRF.
研究图像配准对视神经血流测量重复性的影响。
对10名正常受试者进行检查。进行海德堡视网膜断层扫描成像，以确定颞侧神经视网膜边缘的最佳位置和焦点。针对三种配准方法（中央、鼻侧和颞侧）采集了两张高质量的海德堡视网膜血流仪（HRF）图像。选择一个10×10像素的测量窗口，并在所有图像上精确重现。使用四分位像素值计算毛细血管血流。采用方差分析、组内相关系数（ICC）和重复性系数（CoR）进行分析。
不同方法之间（p = 0.47）或不同检查之间（p = 0.51）均无差异。中央配准的ICC为0.83，鼻侧为0.34，颞侧为0.42。中央配准的CoR为31.5（平均效应235.1），鼻侧为234.6，颞侧为256.7。
使用HRF测量神经视网膜边缘毛细血管血流时，中央配准是最具重复性的方法。
