Sandor T, Rhie F H, Soeldner J S, Gleason R E, Rand L I
Int J Biomed Comput. 1981 Sep;12(5):401-18. doi: 10.1016/0020-7101(81)90052-0.
Computer-aided operator-interactive densitometry was applied to assess the reproducibility or retinal-fluorescein angiograms. To achieve this, the fundus camera images of glass tubings of various diameter filled with fluorescein of varying concentrations were subjected to densitometric analysis. These studies were carried out repeatedly at 9-micrometer and 29-micrometer scanning resolutions by three observers and thus the inter- and intra-operator errors could be estimated. The scanned data were analyzed as both optical densities and intensities for some of the measurements. In both analyzing modes good linearity was obtained when the densitometric response was plotted against tubing diameter for various concentrations. To determine the reproducibility of transit time and retinal circulation time analyses, a randomly selected patient's angiogram was repeatedly analyzed by three observers and compared. From these data the inter- and intra-operator errors were also determined for successive frames and the reproducibility of the area under the dye dilution curves for both arteries and veins was computed. The overall densitometric reproducibility was found to be good; however, practical usefulness of the retinal circulation time remains to be established.
计算机辅助的操作员交互式密度测定法被用于评估视网膜荧光血管造影的可重复性。为实现这一点，对填充有不同浓度荧光素的各种直径玻璃管的眼底相机图像进行密度测定分析。由三名观察者在9微米和29微米的扫描分辨率下反复进行这些研究，从而可以估计操作员间和操作员内误差。对于某些测量，扫描数据作为光密度和强度进行分析。在两种分析模式下，当针对不同浓度将密度测定响应与管径作图时，均获得了良好的线性关系。为了确定通过时间和视网膜循环时间分析的可重复性，三名观察者对随机选择的患者血管造影进行反复分析并比较。从这些数据中还确定了连续帧的操作员间和操作员内误差，并计算了动脉和静脉染料稀释曲线下面积的可重复性。发现总体密度测定可重复性良好；然而，视网膜循环时间的实际实用性仍有待确定。
