J Refract Surg. 2021 Jun;37(6):414-421. doi: 10.3928/1081597X-20210315-03. Epub 2021 Jun 1.
To evaluate an automated method for detecting the cone shape characteristics and to assess the cornea specialists' subjective variability of these measures using different maps.
Topographic images of the anterior and posterior surface of each eye were presented to 12 clinicians in two different types of map: tangential curvature and relative elevation to the best-fit sphere. They were asked to mark the cone center and its boundaries in the two maps without knowing that they belonged to the same patient. The results between the maps were compared to assess the subjective variability dependent on the map type and the automated method was compared against both estimations to assess its accuracy.
Considering the results of anterior and posterior surfaces, there was low agreement between the cone center estimations using different types of maps for 10 of the 12 cases ( < .05), whereas the comparison between the automated method and the two map estimations did not show differences in 11 of the 12 cases ( > .05). There was high variability, up to 55%, among clinicians' estimations of the cone area. The results of the automated method were within the range of the expert's estimations.
An objective, mathematically derived method of determining morphological dimensions of the cone was consistent with clinicians' evaluations. Although there was high variability among the experts' subjective estimates, which were highly influenced by the type of map, the objective method provided a reliable evaluation of the keratoconus shape independent of maps or color scale. .
评估一种自动检测圆锥形状特征的方法,并使用不同的地图评估角膜专家对这些测量值的主观可变性。
将每个眼睛的前表面和后表面的地形图呈现给 12 位临床医生,他们在两种不同类型的地图上进行操作:切向曲率和相对于最佳拟合球的相对高度。他们被要求在不知道它们属于同一患者的情况下,在这两种地图上标记圆锥中心及其边界。比较两种地图之间的结果,以评估依赖于地图类型的主观可变性,并将自动方法与两种估计方法进行比较,以评估其准确性。
考虑到前表面和后表面的结果,在 10 个病例中的 12 个病例中,使用不同类型的地图对圆锥中心的估计结果之间的一致性较差(<0.05),而自动方法与两种地图估计值之间的比较在 11 个病例中没有差异(>0.05)。在 12 位临床医生中,圆锥面积的估计值存在高达 55%的高度可变性。自动方法的结果在专家估计值的范围内。
一种客观的、基于数学的方法,用于确定圆锥的形态尺寸与临床医生的评估一致。尽管专家的主观估计存在高度可变性,并且高度受地图类型的影响,但客观方法提供了一种独立于地图或颜色比例尺的圆锥角膜形状的可靠评估。