This study investigated whether patients with ischaemic retinal vasculitis have a worse visual outcome than those with non-ischaemic disease. A retrospective study was made of 53 patients with idiopathic retinal vasculitis (RV), with minimum 5 year follow-up. Patients were categorised into ischaemic and non-ischaemic groups by fluorescein angiography. Visual outcome was determined by visual acuity at their last attendance. Twenty patients (38 eyes) had ischaemic RV; 33 patients (63 eyes) had non-ischaemic RV. At presentation there was no significant difference between the groups in the proportion of eyes with poor vision (6/60 or less). Ischaemic RV patients had a worse visual outcome than those with non-ischaemic RV: 13 of 38 (34%) eyes in the ischaemic group had a final poor vision compared with 4 of 63 (6%) eyes in the non-ischaemic group (Fisher's exact test, p = 0.0005).