Total right visual loss due to Temporal Arteritis recognised only after left visual deterioration, necessitating maximal steroid therapy and tocilizumab

•Temporal arteritis with arteritic anterior ischaemic optic neuropathy should be treated as bilateral until proven otherwise.•It is essential to examine thoroughly all the parameters of visual function (minimum of visual acuity, pupil reactions, confrontation fields and fundoscopy) in both eyes of a patient who has lost vision.•Ongoing bilateral arteritic anterior ischaemic optic neuropathy should be managed with a combination of prednisone and tocilizumab.