中心性浆液性脉络膜视网膜病变频域光相干断层扫描与时域光相干断层扫描图像比较

目的 比较中心性浆液性脉络膜视网膜病变（CSC）的时域光相干断层扫描（OCT）与频域OCT形态学特征及定量测量的异同。方法 收集确诊为单眼初发CSC连续患者26例26只眼。对所有患眼及其对侧正常眼行时域OCT及频域 OCT检查。时域OCT行黄斑中心凹的水平及垂直线性扫描及放射6线扫描；频域 OCT行黄斑部立体扫描、经黄斑中心凹的水平及垂直5线高清扫描。对比分析两种扫描的图像特征、视网膜分层、定量测量结果的差异。结果 频域OCT可以分别显示视网膜内界膜、视网膜色素上皮(RPE)和全视网膜厚度的三维地形图。CSC眼及对侧正常眼的视网膜外界膜在频域OCT图像中均能清晰显示，而时域OCT图像中大部分不能显示。对侧正常眼视网膜光感受器内外节连接（IS/OS）结构两种OCT图像均能显示，频域OCT图像中CSC眼 65.4% IS/OS结构不清，时域OCT图像中73.4%不清。二者比较，差异无统计学意义（Z=-0.108, P=0.914）。频域 OCT图像中，视网膜外界为RPE高反射带之前，黄斑中心凹厚度对侧正常眼为（180.50±12.69）μm， CSC眼为（158.41±34.20）μm，CSC眼黄斑脱离高度为（245.84±154.61）μm。时域OCT图像中，视网膜外界为IS/OS高反射带之前，黄斑中心凹厚度对侧正常眼为（141.16±12.75）μm，正常眼为（146.40±36.28）μm，CSC眼黄斑脱离高度为（240.32±156.82）μm。两种OCT测量值比较，CSC眼黄斑中心凹厚度差异有统计学意义（t=20.671，P=0.000），CSC眼各测量值差异无统计学意义（t=0.026～1.517，P=0.144～0.980）。结论 与时域OCT相比，频域 OCT可更清楚地显示视网膜的细微结构，对视网膜的外界界定更准确，测量厚度更精确，可以更全面、直观地观察CSC的病理形态学变化和病变层次。

Comparison between time-and Fourier-domain optical coherence tomography in the patients with central serous chorioretinopathy

Objective To compare difference of the cross-sectional pathological imaging and quantitative measurement of central serous chorioretinopathy (CSC) between time-and fourier-domain optical coherence tomography (OCT). Methods Consecutive 26 patients (26 eyes) with unilaterial CSC were subsumed. Bilateral eyes of all the patients underwent time-and fourier-domain OCT. Horizontal and vertical line scanning and radial six-line scanning protocols were used for time-domain OCT examination; horizontal and vertical high resolution five-line scanning and macular cube scanning protocols were used for fourier-domain OCT examination. The characteristics of OCT images, retinal segmentation and the quantitative measurement were compared between these two methods. Results Fourier-domain OCT could yield the three-dimensional images of surface of inner limiting membrane (ILM) and RPE. The band of external limiting membrane (ELM) of normal subjects and CSC patients, and the inner segment and outer segment (IS/OS) of normal subjects could be clearly shown by fourier-domain OCT. However, the band of IS/OS disappeared in 65.4 % of the CSC patients. The outer boundary of retina was defined in front of the retinal pigmental epithelia (RPE) by fourier-domain OCT. The foveal thickness of normal subjects and CSC patients was (180. 50 ±12.69) and (158. 41 ± 34.20) μm, respevtively. The height of detachment of neuralepithelial layer was (245.84± 154.61) μm measured by fourier-domain OCT. The band of IS/OS of normalsubjects could be clearly shown by time-domain OCT. However, the band of IS/OS disappeared in 73.4%of the CSC patients, which showed no difference with fourier-domain OCT (Z=-0. 108, P=0. 914). Theouter boundary of retina was defined in front of the IS/OS band by OCT. The foveal thickness of normal subjects was (141.16±12.75) μm, which was thinner than that measured by fourier-domain OCT (t= 20. 671,P= 0. 000). The foveal thickness and the height of detachment of neural epithelial layer was (146.40± 36.28) μm and (240. 32±156. 82) μm measured by time-domain OCT, respectively, which showed no significant difference with which measured by fourier-domain OCT (t value was from 0. 026 to 1. 517, P value was from 0. 144 to 0. 980). Conclusions Fourier-domain OCT yields better visualization of intraretinal layers and more accurate definition of outer boundary of retina than time-domain OCT. Thus the measurements by fourier-domain OCT were more accurate. Moreover, three-dimensional images of CSC shown by fourier-domain OCT enable the comprehensive observation of pathological morphology and location.