Morning glory disc anomaly in association with ipsilateral optic nerve glioma.

Comment. Improvement in vision rarely occurs in patients with AION due to GCA, presumably because there has been complete occlusion of the posterior ciliary arteries causing optic nerve head infarction. Although some series have reported improvement in up to one-third of patients, there has often not been an improvement in the visual field, suggesting that the apparent recovery could be an artifact of visual acuity testing (eg, learned ability to eccentrically fixate). In series in which visual acuity and visual field changes have been reported, improvement in both has been observed in 4% to 5% of eyes, although the improvement was not substantial in most cases. Factors that predict visual recovery remain unclear, although the chance of improvement might be higher when treatment with corticosteroids is started early. Our patient with biopsy-proven GCA initially had no light perception in one eye, associated with signs of AION. She was immediately treated with prednisone and subsequently experienced dramatic improvement in both visual acuity and visual field over subsequent weeks. The presence of hyperemic rather than pallid optic disc edema and the delayed rather than absent choroidal filling on fluorescein angiography suggest that there was severe inflammatory narrowing, rather than complete occlusion, of the posterior ciliary arteries or development of collaterals. We propose that this unusual extent of vision recovery occurred because there was reversible ischemia rather than infarction of the optic nerve head. We suggest that hyperemic optic disc edema and delayed choroidal filling without posterior ciliary artery occlusion could predict a chance of improvement in patients with AION due to GCA.