Abstract
Purpose: :
To compare retinal thickness measurements and segmentation performance between Fourier-Domain Optical Coherence Tomography (FD-OCT) and our custom-built OCT Retinal Image Analysis software (OCTRIMA) based on StratusOCT (Carl Zeiss Meditec, Dublin, CA) images.
Methods: :
11 eyes of 11 elderly subjects were recruited in our study (73±7years [mean±SD]). All patients underwent uneventful phacoemulsification surgery with PCL implantation 6-12 months prior to enrollment. Exclusion criteria were the presence of systemic diseases or any retinal disease including glaucoma. Standard macular mapping by StratusOCT and MM5 and MM6 scanning protocols by an RTVue device (Optovue, Fremont, CA) were performed. The OCT raw data were exported and analyzed using OCTRIMA. Total retinal thickness measured by MM5 and MM6 and the thickness of the ganglion cell complex (RNFL+GCL+IPL) measured by MM6 was compared for each ETDRS-like region with corresponding OCTRIMA results. Because of the size of the MM5 protocol only the foveal and pericentral regional data were compared.
Results: :
There was a high correlation observed when comparing OCTRIMA with MM5 and MM6 total retinal thickness and MM6 GCC measurements (pearson correlation coefficients between 0.93-0.97, 0.82-0.94 and 0.73-0.88, respectively and mean difference between 1.7-14.1, 1.9-11.9 and 6.3-12.4µm, respectively).
Conclusions: :
We could demonstrate the high correspondence of retinal thickness measurements not only for total retinal thickness but also for the segmentation of intraretinal layers between FD-OCT and Stratus OCT images further assessed by OCTRIMA. Despite the worse resolution of time-domain OCT we could achieve a high correspondence of retinal layer segmentation with FD-OCT in elderly subjects who are known to have bad fixation cooperation. Taking into consideration the higher price of FD-OCT systems and the widespread use of Stratus OCT worldwide, our software can be of substantial value in studies of macular pathophysiology.
Keywords: imaging methods (CT, FA, ICG, MRI, OCT, RTA, SLO, ultrasound) • retina