Yamashita Toshifumi, Terasaki Hiroto, Sakamoto Taiji
Department of Ophthalmology, Kagoshima University Graduate School of Medical and Dental Sciences, Kagoshima, Japan.
BMC Ophthalmol. 2016 Jul 26;16:124. doi: 10.1186/s12886-016-0306-1.
Optical coherence tomography (OCT) is being used increasingly to evaluate and manage a variety of retinal diseases, but not much is known about the minification of the OCT images in gas-filled eyes. The purpose of this study was to investigate the effect of gas-filled eyes on the size of the OCT images.
This was retrospective case series of 81 consecutive eyes of 79 patients who had macular hole surgery between April 2012 and September 2014. Images of the optic disc were taken with a spectral domain-OCT instrument 2 days after surgery in gas-filled, pseudophakic eyes and from the same eyes but fluid-filled one month after the surgery. The vertical length, horizontal width, and the area of the optic disc were measured in the OCT images.
Clear images were obtained from 50 eyes of 49 patients (mean age 66.4 ± 5.9 years). The mean vertical length and mean horizontal width of the optic disc in the gas-filled eyes were about 25 % shorter than that of fluid-filled eyes (vertical, 1213.8 ± 170.5 and 1650.6 ± 195.9 μm, P < 0.01; horizontal, 1169.4 ± 143.1 and 1526.4 ± 219.9 μm, P < 0.01). The mean area of the optic disc was 1.12 ± 0.34 mm(2) in gas-filled eyes which was significantly smaller than that in fluid-filled eyes (1.88 ± 0.37 mm(2)) by 40.4 %.
The fundus images of gas-filled eyes are significantly smaller than that in the same fluid-filled eyes. The minification of the OCT images should be considered when analyzing images obtained from gas-filled eyes.
UMIN000007517 . Date of registration: 3/21/2012.
光学相干断层扫描（OCT）越来越多地用于评估和处理各种视网膜疾病，但对于气体填充眼内OCT图像的缩小情况了解不多。本研究的目的是调查气体填充眼对OCT图像大小的影响。
这是一项回顾性病例系列研究，纳入了2012年4月至2014年9月间接受黄斑裂孔手术的79例患者的81只连续眼。在气体填充的假晶状体眼手术后2天，以及同一眼在手术后1个月液体填充时，使用光谱域OCT仪器拍摄视盘图像。在OCT图像中测量视盘的垂直长度、水平宽度和面积。
从49例患者的50只眼中获得了清晰图像（平均年龄66.4±5.9岁）。气体填充眼中视盘的平均垂直长度和平均水平宽度比液体填充眼短约25%（垂直方向：1213.8±170.5和1650.6±195.9μm，P<0.01；水平方向：1169.4±143.1和1526.4±219.9μm，P<0.01）。气体填充眼中视盘的平均面积为1.12±0.34mm²，明显小于液体填充眼中的面积（1.88±0.37mm²），小40.4%。
气体填充眼的眼底图像明显小于同一眼液体填充时的图像。在分析从气体填充眼获得的图像时，应考虑OCT图像的缩小情况。
UMIN000007517。注册日期：2012年3月21日。
