In this regard, Sanz-Marco et al. [63] analyzed via FCM the CD4/CD8 ratio in the aqueous humor of patients undergoing an acute episode of uveitis, suggesting that the characterization of CD4 and CD8 in uveitis with T-lymphocyte involvement and difficult diagnosis (virus uveitis, sarcoidosis, masquerade syndromes in T lymphomas) may help in managing the affected patients. Here, CD4 is linked to sarcoidosis.