Abstract
PURPOSE: To assess acute IOP changes after anti-VEGF injections in patients with Pseudoxanthoma elasticum (PXE) compared to other retinal diseases. METHODS: Twenty eyes of patients with PXE (mean age 63.4 ± 6.4 years) and 30 control eyes (mean age 64.8 ± 11.8 years) were included. IOP was measured prior and one, five, and 15 minutes after intravitreal injection of 50 µL anti-VEGF agent. The post-injection IOP curve was modeled by an exponential decay function, and the resulting exponential time constant (tau) served as the outcome variable in the multivariable models. RESULTS: IOP raised markedly after anti-VEGF injection in both groups, without significant difference in PXE compared to controls. The median tau in the PXE group was 8.6 minutes (interquartile range [IQR] = 8.2-9.4) versus 7.6 minutes (IQR = 6.8-8.9) in the control group (P = 0.02). Seven PXE patients and one control patient reported a previous transient vision loss after anti-VEGF injection. Univariate analysis showed that the diagnosis of PXE (1.12, P = 0.006), angioid streak length (0.12, P = 0.01), prior transient vision loss (1.77, P = 0.001), peripheral artery disease (0.96, P = 0.04) and the number of previous anti-VEGF injections (0.02, P = 0.014) were significantly associated with higher tau values. CONCLUSIONS: The time to restore to baseline IOP after anti-VEGF injection is longer in PXE patients. Given the early need for anti-VEGF treatment, frequent injections, and the possible heightened vulnerability (e.g., optic disc drusen) in PXE patients, clinical trials on pre-injection IOP-lowering measures warrant consideration.