To compare the functional and anatomical outcomes of central retinal vein occlusion (CRVO) according to the presence of glaucoma before the onset of CRVO, and to assess whether pre-existing glaucoma affects the prognosis of CRVO in terms of development and conversion to ischaemic CRVO.
In this retrospective cohort study, patients with treatment-naïve CRVO were enrolled between December 2009 and February 2019. The patients were classified into two groups according to the presence of pre-existing primary open-angle glaucoma at CRVO diagnosis. We reviewed medical records regarding basic demographics, ocular characteristics and treatments. The effects of pre-existing glaucoma on the occurrence of ischaemic CRVO were also investigated using Cox proportional hazard models.
Of 166 eyes from 166 patients, 26 (15.7%) had pre-existing glaucoma. The pre-existing glaucoma group revealed significantly older (69.4 ± 13.3 versus 56.5 ± 15.9) and lower BCVA at baseline (1.06 ± 0.75 versus 0.64 ± 0.58, logMAR) and final visits (1.56 ± 1.35 versus 0.64 ± 0.48, logMAR) (all p < 0.05) than non-glaucomatous group. In terms of perfusion status of CRVO, the glaucoma group showed higher incidence of ischaemic CRVO (30.8% versus 5.3%, p = 0.052) at initial and last visits as well as more disorganization of retinal inner layers (DRIL) at 3 months (76.0% versus 49.6%, p = 0.015). Pre-existing glaucoma (hazard ratio (HR) = 2.141, p = 0.014), lower vision at baseline (HR = 2.071, p = 0.001) and DRIL at 3 months (HR = 2.905, p = 0.011) were significant risk factors for the occurrence of ischaemic CRVO.
In patients with CRVO, pre-existing glaucoma was associated with poorer visual and anatomical outcomes, and played as a significant risk factor for the development and conversion to ischaemic CRVO with lower vision and presence of DRIL at early phase of CRVO.

© 2020 Acta Ophthalmologica Scandinavica Foundation. Published by John Wiley & Sons Ltd.