Eye Department, University Federico II, Naples, Italy.
Eye (Lond). 2009 Nov;23(11):2071-8. doi: 10.1038/eye.2008.363. Epub 2008 Dec 12.
To compare retinal thickness and volume measurements obtained with Stratus time domain optical coherence tomography (OCT) and spectral domain scanning laser ophthalmoscope OCT (SD-SLO/OCT).
In a cross-sectional study, 52 eyes with a normal macula, 30 eyes with retinal oedema, and 10 eyes with a myopia higher than 6 D have been evaluated with both time domain OCT (TD-OCT, Stratus OCT, Carl Zeiss Meditec, USA) and SD-SLO/OCT (OTI, Toronto, Canada). Retinal thickness and volume measurements in the nine areas of the 6-mm ETDRS ring were compared. Artefacts were defined as the discordance between the automatically detected anterior and posterior retinal boundaries and the boundaries detected by the examiner.
Artefacts were more frequent with TD-OCT (35 vs26%). Mean retinal thickness was significantly higher with SD-SLO/OCT by 30.1 microm (+/-25.8) (P=0.003) in presence of the artefacts and by 39.2 microm (+/-25.8) (P=0.003) after their exclusion. The correlation between the two retinal thickness data sets before exclusion of the artefacts (r=0.59, P<0.001) increased after their removal (r=0.84, P<0.001). A strong correlation was present between the two retinal volume data sets before (r=0.94, P<0.001) and after exclusion of the artefacts (r=0.96, P<0.001).
SD-SLO/OCT produced fewer artefacts than Stratus TD-OCT. This could be attributed to the greater resolution and acquisition speed of SD-SLO/OCT. The macular retinal thickness values measured with SD-SLO/OCT were significantly higher than those measured with Stratus TD-OCT. Retinal volumes measured with Stratus TD-OCT and SD-SLO/OCT were strongly correlated.
比较应用频域光学相干断层扫描(SD-OCT)和时域光学相干断层扫描(TD-OCT)测量视网膜厚度和体积的结果。
本研究为横断面研究,对 52 只正常眼、30 只视网膜水肿眼和 10 只高度近视眼(>6 D)分别行 TD-OCT(Stratus OCT,德国蔡司公司)和 SD-OCT(OTI,加拿大)检查,对 6mm ETDRS 环 9 个区域的视网膜厚度和体积进行比较。将自动探测到的视网膜前后边界与检查者探测到的边界之间的差异定义为伪影。
TD-OCT 检查的伪影较 SD-OCT 多(35 比 26%)。存在伪影时,SD-OCT 测量的视网膜厚度比 TD-OCT 高 30.1μm(25.8μm)(P=0.003),去除伪影后,二者的差异仍有 39.2μm(25.8μm)(P=0.003)。去除伪影前,两种方法得到的视网膜厚度数据之间的相关性(r=0.59,P<0.001)在去除伪影后明显增强(r=0.84,P<0.001)。去除伪影前,两种方法得到的视网膜体积数据之间的相关性(r=0.94,P<0.001)在去除伪影后进一步增强(r=0.96,P<0.001)。
SD-OCT 的伪影比 TD-OCT 少,这可能与 SD-OCT 较高的分辨率和采集速度有关。SD-OCT 测量的视网膜厚度值明显高于 TD-OCT,两种方法测量的视网膜体积之间有很强的相关性。