Evaluation of change in the vascular density of choriocapillaris on optical coherence tomography angiography in eyes with serpiginous choroiditis

PURPOSE: Serpiginous choroiditis (SC) is primarily an inflammation of choriocapillaris leading to nonperfusion. A quantitative assessment of choriocapillaris perfusion can be done by measuring the flow-density by OCT-Angiography (OCTA). This study measures a change in the flow-density of choriocapillaris with the resolution of inflammation. METHODS: The OCTA images of a choriocapillaris slab of 30 eyes with active SC were subjected to binarization and vessel density was measured at baseline and final visits and compared. RESULTS: Upon comparing the vessel density of the affected areas by OCTA of choriocapillaris-slab at baseline and final visits, there was statistically significant (P < 0.0001) improvement after the resolution of inflammation. The vessel density of a demarcated normal area was significantly higher when compared to that of lesions at baseline (P < 0.0001) and final visit (P < 0.0001). CONCLUSION: OCTA is a useful tool to assess reduction in the inflammatory activity on treatment in SC. This study shows that with treatment the perfusion of choriocapillaris improves; however, it remains lower than normal.