Case reportMRI findings of optic pathway involvement in Miller Fisher syndrome in 3 pediatric patients and a review of the literature

•Miller Fisher syndrome (MFS) is a rare variant of Guillain-Barré syndrome (GBS).•Cranial nerve involvement is not infrequent in MFS.•Optic nerves/pathways can show abnormal enhancement.•Imaging findings do not always correlate with clinical cranial nerve involvement.

Background: Miller Fisher syndrome (MFS) is a rare demyelinating condition which may have involvement of cranial nerves. There are a few case reports of optic pathway involvement in children. We describe 3 patients with optic pathway enhancement in pediatric patients with MFS. Case series: We retrospectively reviewed brain imaging findings in 17 pediatric patients with of Guillain-Barré syndrome (GBS) meeting Brighton criteria who had brain MRIs performed during their acute illness. Cranial nerve enhancement was seen in 6/17 patients and optic nerve/chiasm enhancement was seen in 3 patients. Conclusion: Cranial nerve enhancement and optic pathway in particular, can be seen in patients with MFS. Imaging findings do not always correlate with clinical manifestations of cranial nerve involvement.