Tasleem Ahmad1, Charlotte Jordan2, Daniel A. Scott1, Nazima Ali2, Joanne L. Sims3, Rachael Niederer1

Purpose: To examine indocyanine green angiography (ICGA) features of hypofluorescent dark dots in uveitis.
Methods: All subjects with a diagnosis of sarcoidosis, tuberculosis, birdshot chorioretinopathy (BCR), Vogt-Koyanagi Harada (VKH) syndrome, multifocal choroiditis (MFC) or sympathetic ophthalmitis with ICGA performed from 2015 to 2022 were included in the study. ICGA was analysed for the presence of hypocyanescent dark dots, number of lesions, size of lesions, heterogeneity of lesion size, confluence, distribution and change in lesion parameters over time. 
Results: A total of 859 ICGA images from 74 eyes of 43 patients were included in the study. Significant differences were observed between hypofluorescent dark dots observed in the different uveitis aetiologies. The number of spots observed was greatest in BCR and lowest in sarcoidosis and tuberculosis (p < 0.001). Total spot area was highest in BCR and MFC (p = 0.055). Average area differed significantly between aetiologies, with the smallest lesions seen in VKH and sympathetic ophthalmitis, and the largest lesions seen in MFC (p = 0.047). Lesions in sarcoid, tuberculosis, BCR and MFC were more likely to be confluent in areas, whereas in VKH and sympathetic ophthalmitis they were clearly demarcated.  Conclusion: Our study analysed the features of hypofluorescent dark dots in six different uveitic conditions. Significant differences were observed in the ICGA characteristics of the spots in these different diseases. This study highlights the importance of identifying these features, as it may help in the diagnosis and management of these ocular diseases.