Department of Surgical Sciences, Eye Clinic, University of Cagliari, Cagliari, Italy.
Invest Ophthalmol Vis Sci. 2014 Jul 1;55(7):4533-40. doi: 10.1167/iovs.14-14666.
To analyze in vivo the dynamic changes induced by different artificial tears (ATs) in the precorneal tear film (PCTF) and lower tear meniscus (LTM) by using spectral-domain (SD) anterior segment optical coherence tomography (OCT).
We prospectively examined 42 normal human eyes by using SD-OCT imaging. On the day before OCT imaging, all enrolled subjects were evaluated for abnormalities of ocular surface. All tear film images were obtained before and after instillation of three different types of ATs (mucomimetic, lipid-based, and saline) in five serial scans: immediately (within 30 seconds), at the first, fifth, 10th, and 20th minute. Subjects received a drop of 35 μL in one randomly selected eye. All examinations were conducted in the same conditions of temperature, brightness, humidity, and time of day.
Changes in the morphological pattern of both LTM and PCTF were associated with the type of artificial tear instilled on the ocular surface. Similarly, the radius of curvature (rc), the height (h), and the depth (d) showed dynamic variations depending on treatment. Although by the 20th minute, both h and d returned to baseline values in all groups, a significant difference in rc (compared with baseline) was detected for mucomimetic ATs (P = 0.04) and lipid ATs (P = 0.02).
Spectral-domain OCT imaging has preliminarily proved to be a noninvasive tool to evaluate, in real time, the different changes induced by ATs instillation. An important stride in understanding the clinical response to various tear substitutes can be achieved by this objective and quantitative approach.
利用频域（SD）眼前节光学相干断层扫描（OCT）分析不同人工泪液（AT）在角膜前泪膜（PCTF）和下泪膜弯月面（LTM）中引起的体内动态变化。
我们前瞻性地使用 SD-OCT 成像检查了 42 只正常人类眼睛。在 OCT 成像前一天，所有入组的受试者都接受了眼表面异常评估。所有泪膜图像均在使用三种不同类型的 AT（粘弹性、基于脂质和盐水）进行五次连续扫描前和后获得：立即（在 30 秒内）、第一次、第五次、第十次和第二十分钟。受试者在一只随机选择的眼睛中滴入 35 μL 的滴剂。所有检查均在相同的温度、亮度、湿度和一天中的时间条件下进行。
LTM 和 PCTF 的形态变化与眼表面滴注的人工泪液类型有关。同样，曲率半径（rc）、高度（h）和深度（d）也表现出随治疗的动态变化。尽管在第 20 分钟时，所有组的 h 和 d 均恢复到基线值，但在粘弹性 AT（P=0.04）和脂质 AT（P=0.02）中检测到 rc 与基线相比有显著差异。
频域 OCT 成像已初步证明是一种非侵入性工具，可实时评估 AT 滴眼引起的不同变化。这种客观和定量的方法可以在理解对各种泪替代物的临床反应方面取得重要进展。
