1/17/2024 0 Comments Spectralis 7 line raster scan8 Comparative studies have failed to demonstrate a statistically significant improvement in CR for newer spectral domain devices evaluating retinal thickness in DME. Repeatability of OCT retinal thickness measurements has been studied in diabetic macular edema using time domain devices, with estimates for the coefficient of repeatability (CR) for retinal thickness in the central subfield of 21 7 and 38 μm. 3– 6 These trials have used quantitative OCT measures in their retreatment criteria. 1, 2 Clinical trials of anti-VEGF agents have demonstrated the superiority of bevacizumab and ranibizumab over conventional laser therapy in this condition. This finding informs clinical practice and clinical trial design.ĭiabetic macular edema (DME) is the leading cause of vision loss in a working age population. Scan sets from 13 subjects had significant boundary detection error reanalysis with these excluded yielded a CR for the central subfield of 7.44 μm with CR for all other subfields 8 μm can be considered more indicative of true clinical change rather than measurement variability. In other subfields, CR ranged from 6.54 to 18.25 μm. Scans were evaluated for significant automated retinal boundary detection error and revised estimates for CR calculated with these scans excluded.ĬR in the central subfield was 8.03 μm (95% confidence interval 7.70–8.35 μm). Bland-Altman coefficients of repeatability (CR) were calculated for automated retinal thickness measurements in the nine Early Treatment of Diabetic Retinopathy Study (ETDRS) subfields, center point thickness, and total macular volume. When planning and conducting multicenter studies, one has to be especially aware of the differences in delineating threshold algorithm lines by different SD OCT devices.We estimated coefficients of repeatability for Spectralis optical coherence tomography (OCT)–derived automated retinal thickness and volume measurements in subjects with center-involving diabetic macular edema (DME).Ī total of 50 eyes of 50 consecutive patients with center-involving DME underwent four consecutive “fast” volume scans at a single session using one OCT device operated by one of two experienced operators. Our study indicates that there are significant differences in CRT values in patients with vascular PED, due to different segmentation algorithms and a high error rate in automatically set threshold lines. We obtained the mean value of central point neurosensory retinal thickness of each central single scan after manual delineation, and found a significant correlation (r = 0.819, p < 0.001). There were failures in positioning the outer retinal boundary line in 50% of Cirrus scans and in 73.52% of Spectralis scans. Mean central retinal thickness (CRT) was 262.38 μm ± 133.18 (176-507 μm) in Cirrus and 337.82 μm ± 137.75 (277-790 μm) in Spectralis scans,mainly caused by different software approaches in positioning the posterior threshold line, following the PED in Cirrus OCT whereas remaining unelevated in Spectralis OCT. OCT images of 34 eyes of 28 patients with a mean age of 71 years and a mean distance visual acuity (VA) of 0.70 ETDRS were analyzed. Scanning with the Cirrus HD OCT was performed with the 512 × 128 scan pattern scans performed with the Spectralis OCT were 20 × 15 degree raster scans consisting of 19 high-speed line scans. Main objectives were to observe differences in central retinal thickness (CRT) values and failures in automated threshold delineation, as well as central point thickness values obtained after manual correction of threshold lines. OCT images of patients with vascular PED due to AMD, obtained with Cirrus and Spectralis OCT, were retrospectively analyzed. Automatically measurements of retinal thickness by optical coherence tomography (OCT) facilitate the assessment of various retinal diseases.The aim of this retrospective study was to report macular thickness measurements in eyes with vascular pigment epithelial detachment (PED) due to age-related macular degeneration (AMD) by using two different commercially available spectral domain (SD) OCT instruments and to consequently point out differences in their algorithm software.systems.
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