Abstract
Purpose: :
To compare results obtained with the Fast Imaging protocol with results from Standard Macular Imaging by Optical Coherence Tomography (OCT) in patients with Birdshot chorioretinopathy.
Methods: :
Eighty patients with Birdshot chorioretinopathy, seen in a single center, were included. Optical Coherence Tomography was performed with an OCT3 (OCT3 Zeiss–Humphrey, San Leandro, CA, USA). Two protocols of acquisition were used: Macular Thickness Map (MTM) and Fast Macular Thickness Map (FMTM). MTM was based on consecutive acquisitions of 6 sections with 512 A–scans and FMTM was based on simultaneous acquisitions of 6 sections with 128 A–scans. Intraclass correlation coefficients were calculated for macular thickness in 1 mm diameter (A1), foveal thickness and macular volume. The duration of both examination methods was timed during a repeat visit visit for a subgroup of 40 patients.
Results: :
The mean duration of acquisition was 65.6 seconds with the MTM protocol and 9.6 seconds with the FMTM protocol. Measurements by MTM and FMTM were respectively 187 ± 98.5 µm (range 85–768) and 197 ± 114.7 µm (range 84–826) for average foveal thickness, 224 ± 87.3 µm (range 118–768) and 228.5 ± 104 µm (range 118–804) for average macular thickness (A1), and 7.1 ± 1.4 mm3 (range 4.6– 14.7) and 7,0 ± 1.6 mm3 (range 4.2–15.3) for average macular volume. The intraclass correlation coefficient was 0.98 [95% CI 0.95–0.99] for macular thickness, 0.97 [95% 0.94–0.99] for foveolar thickness and 0.92 [95% CI 0.95–0.99] for macular volume. The mean of the differences between standard and fast protocol was –3.8 µm for foveal thickness (paired t–test, p=0.008) and –10.6µm for macular thickness (p<0.001). No statistical difference was observed for macular volume.
Conclusions: :
Results from Fast and Standard macular imaging by OCT were highly correlated, but with slightly greater measurements of macular thickness using Fast macular imaging.
Keywords: autoimmune disease • retinochoroiditis • imaging methods (CT, FA, ICG, MRI, OCT, RTA, SLO, ultrasound)