Optical Intensities of Different Compartments of Subretinal Fluid in Acute Vogt-Koyanagi-Harada Disease

PURPOSE: To investigate the optical intensity in different compartments of subretinal fluid in acute Vogt-Koyanagi-Harada (VKH) disease by using spectral domain optical coherence tomography (SD-OCT). METHODS: Fifty acute VKH eyes and 25 cases with acute central serous chorioretinopathy (CSCR) were included in this retrospective comparative study. The optical intensities of subretinal fluid, vitreous humour and the entire scanned region displayed by SD-OCT were measured with Image J by three independent readers. In the VKH eyes with subretinal septa, the subretinal fluid was segmented into two types of compartments, supra-septa space and sub-septa space. Optical intensity ratios of different compartments of subretinal fluids divided by vitreous humour or the entire scanned region were compared. RESULTS: The measurement of optical intensity was highly reproducible (intraclass correlation coefficient> 0.9). The optical intensity of the supra-septa space divided by the vitreous humour was significantly higher compared to that of sub-septa space in VKH (mean difference = 4.27 ± 5.15, p <0.001). The optical intensity ratio of the supra-septa space (1.14 ± 0.12), but not subsepta space (1.05 ± 0.05) in VKH, was significantly higher compared to that of the subretinal space in VKH without the subretinal septa (1.07 ± 0.08), and the subretinal fluid in CSCR (1.08 ± 0.09). Similar results were found for the optical intensity ratios divided by the entire scan region. CONCLUSION: The optical intensity in the supra-septa space of VKH is higher compared to the sub-septa space in VKH, subretinal space in VKH and CSCR, suggesting that the components in these spaces are different.