Tonic pupils from giant cell arteritis

Decreased blood flow in the ophthalmic artery, central retinal artery, and short posterior ciliary arteries may be detected on orbital colour Doppler imaging in patients with GCA. 9 Markedly reduced blood flow was found with orbital colour Doppler imaging in both orbits in our patient, despite her visual loss being unilateral. Iris ischaemia would result in poorly reactive pupils to both light and accommodation, without a tonic near reaction or denervation hypersensitivity. [...]the findings in our patient strongly suggest that the tonic pupils resulted from ischaemic damage to the ciliary ganglion or the postganglionic ciliary nerves which are responsible for pupillary constriction.