METHODS: TMH was assessed using both SEC and conventional slit lamp examination. The images were analyzed using the software ImageJ 1.53t (National Institutes of Health, Bethesda, MD, USA). A common measurement unit scale was established based on a paper strip, which was used as a calibration marker to convert pixels into metric scale. A color threshold was applied using uniform parameters for brightness, saturation, and hue. The images were then binarized to black and white to enhance the representation of the tear menisci. A 2 mm area around the upper and lower meniscus in the central eye lid zone was selected and magnified 3200 times to facilitate manual measurement. The values obtained using SEC were compared with those obtained with a slit lamp.
RESULTS: The upper and lower TMH values measured using the SEC were not statistically different from those obtained with a slit lamp (0.209 ± 0.073 mm vs. 0.235 ± 0.085, p = 0.073, and 0.297 ± 0.168 vs. 0.260 ± 0.173, p = 0.275, respectively). The results of Bland-Altman analysis demonstrated strong agreement between the two instruments, with a mean bias of -0.016 mm (agreement limits: -0.117 to 0.145 mm) for upper TMH and 0.031 mm (agreement limits: -0.306 to 0.368 mm) for lower TMH.
CONCLUSIONS: The SEC demonstrated sufficient validity and reliability for assessing TMH in healthy eyes in a clinical setting, demonstrating concordance with the conventional slit lamp examination.
方法:使用SEC和常规裂隙灯检查评估TMH。使用软件ImageJ1.53t(美国国立卫生研究院,贝塞斯达,MD,美国)。建立了基于纸条的通用测量单位比例尺,用作校准标记,将像素转换为公制刻度。使用均匀的亮度参数应用颜色阈值,饱和度,和色调。然后将图像二值化为黑色和白色以增强泪液半月板的表示。选择在中央眼睑区域中的上下弯月面周围的2mm区域并放大3200倍以便于手动测量。将使用SEC获得的值与使用裂隙灯获得的值进行比较。
结果:使用SEC测得的上下TMH值与使用裂隙灯(0.209±0.073mmvs.0.235±0.085,p=0.073,0.297±0.168vs.分别为0.260±0.173,p=0.275)。Bland-Altman分析的结果表明,两种仪器之间具有很强的一致性,上TMH的平均偏差为-0.016mm(一致极限:-0.117至0.145mm),下TMH的平均偏差为0.031mm(一致极限:-0.306至0.368mm)。
结论:SEC证明了在临床环境中评估健康眼睛TMH的有效性和可靠性。证明与常规裂隙灯检查一致。