A patient with severe retinal vasculitis performed a headstand, with immediate loss of vision in the left eye-from 6/5 to just being able to perceive light. T1 and T2 weighted magnetic resonance scans showed a vitreous haemorrhage, with a fluid level within the vitreous cavity. Retinal vasculitis is an inflammatory disease of the retinal circulation that can be associated with systemic inflammatory or infectious disorders such as Behçet's disease, sarcoidosis, tuberculosis, herpes, and toxoplasmosis. Retinal ischaemia as a result of this process produces neovascularisation within the posterior segment, and sudden head movements in such patients can cause intraocular bleeding.
Nishal Patel(email@example.com) specialist registrar in ophthalmology, Genevieve Larkin consultant ophthalmologist, King's College Hospital, London SE5 9RS, Miles Stamford professor, medical eye unit, St Thomas' Hospital, London
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