Longitudinal follow-up of Choroidal Granulomas with Indocyanine Green Angiography And Optical Coherence Tomography Angiography: a lesion-based analysis

Purpose: To investigate choroidal granulomas visualized by indocyanine green angiography (ICGA) and Optical Coherence Tomography Angiography (OCTA) in response to treatment. Methods: Ten eyes of eight patients with tubercular, sarcoid or Vogt-Koyanagi-Harada associated choroidal granulomas were evaluated in this multicentric study. All patients underwent ICGA and OCTA at baseline, 1 and 3 months after treatment onset. Granulomas were identified as hypofluorescent lesions on intermediate ICGA phases. Late ICGA behavior and OCTA visualization were assessed. Results: On baseline intermediate ICGA, 222 choroidal granulomas were detected. Overall, 174/222 granulomas were detected on baseline OCTA images. At 1 month, 28% of lesions were healed and 48 late ICGA hyper-fluorescent lesions were identified. At 3 months, 63% of baseline lesions were healed, with 33 persistent late hyper-fluorescent lesions. OCTA sensitivity was reduced at 1 and 3 months compared to baseline. Some flow-voids detected on OCTA at 1 and 3 months did not correspond to any visible lesion on ICGA. Conclusions: Different healing behaviors of choroidal granulomas were identified combining ICGA and OCTA analysis. Late ICGA hyper-fluorescent lesions may be the consequence of a possible fibrotic shift. Structural changes in the choroid may persist after active granulomas resolution resulting in persistent flow voids on OCTA.