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This is a retrospective case series about the use of prostaglandin analogues in the management of increased IOP in patients with uveitis. In particular, the aim of this study by Chang et al. (1142) was to assess whether treatment with prostaglandin analogues was associated with an increase in the rate of anterior uveitis and occurrence of cystoid macular edema. The paper reported a significant IOP reduction after prostaglandin analogues use without a significant increase in the incidence of cystoid macular edema and occurrence of anterior uveitis. As in every retrospective study, there are some points of weakness that can potentially affect the validity of the results and conclusions. First, potential bias might arise from selection of cases: 'all consecutive patients with uveitis and raised IOP treated with a PG' were selected for inclusion in the study. It is possible that this sample included only patients with mild uveitis and/or with particularly high IOP (as stated, IOP of 30 mmHg or more in the majority of cases) because PG use is commonly considered as contraindicated in patients with uveitis. The study population of 84 cases was very heterogeneous including all forms of uveitis with very different risk of developing anterior uveitis or macular edema. In addition, it is not clear which criteria were used to define IOP requiring treatment. A second issue of concern is assessment of outcome. Cases and controls were the same patients and rates of complications during 'a treatment period' were the outcomes of the study: although it is stated that all included non-PG treatment periods always preceded PG use, this design might have led to a wrong estimate of occurrence of endpoints. In addition the frequency and the type of examinations (angiographies or OCT) is not known and the likelihood of a correct diagnosis in all different periods of the study seems uncertain. The level of evidence seems not sufficient to thoroughly support the strong study conclusions. In order to justify the adoption of a potentially dangerous treatment, results form at least one large randomized clinical trials are needed.