Dural venous sinus thrombosis (DVST) is an important cause of papilledema. Patients diagnosed with DVST should undergo work-up for underlying hypercoagulable state, including genetic causes. One important prothrombotic mutation is in the JAK2 gene, which is a driver of myeloproliferative neoplasms including polycythemia vera (PV). We aimed to determine the prevalence of JAK2 mutation in patients in presenting to neuro-ophthalmology clinic with DVST and papilledema.

Retrospective case series of patients seen in a tertiary neuro-ophthalmology practice who presented with papilledema due to DVST and were investigated for presence of JAK2 mutation.

Four out of 15 patients with DVST (26%) were found to have JAK2 V617F mutation which led to subsequent diagnosis of PV in 2. One additional patient had a known diagnosis of essential thrombocytosis. We describe the clinical presentation of these four patients with papilledema and JAK2 mutation.

A significant proportion of patients with papilledema secondary to DVST will harbor mutations in the JAK2 gene. Clinicians should be aware of this mutation as early testing will facilitate timely diagnosis and treatment of myeloproliferative disease to improve prognosis and reduce risk of recurrent thrombotic events.

To describe clinical characteristics of Canadian patients with myelin-oligodendrocyte glycoprotein immunoglobulin-G optic neuritis (MOG-IgG ON).

Retrospective observational case series of MOG-IgG seropositive patients with ON referred to tertiary neuro-ophthalmology practices. Outcome measures included clinical characteristics, radiologic findings, and visual outcomes.

Forty-six eyes of 30 patients were included. Twenty-three (76.7%) were women, mean onset age was 40.7 years (range 16–77), and most were Caucasian. Seventeen (56.7%) presented with their first ON episode. Sixteen (53.3%) had bilateral eye involvement. Isolated ON without associated neurological symptoms occurred in 90.0%. In 22 patients with acute ON (seen within 1 month of onset), presenting mean visual acuity (VA) was 20/258 (logMAR 1.11), mean deviation (MD) on Humphrey visual fields was −16.90 ± 10.83 dB, and peripapillary retinal nerve fiber layer (RNFL) thickness on ocular coherence tomography (OCT) was 164.23 ± 46.53 um. Orbital magnetic resonance imaging (MRI) within 1 month of symptom onset for 19 patients demonstrated orbital optic nerve enhancement in 11 (57.9%) and perineural enhancement in 11 (57.9%). Brain MRI was normal in 28 (93.3%) patients. Twenty out of 22 patients with acute presentation were treated with high-dose glucocorticoids and 5 with plasma exchange in addition to corticosteroids. Long-term immunosuppression was utilized in 9 (30%) out of all 30 patients. Final VA was 20/30 (logMAR 0.18), MD was −7.17 ± 8.85 dB, and RNFL thickness was 72.15 ± 20.16 um.

MOG-IgG ON in Canada has a variable presentation with most patients having substantial initial vision loss with good recovery. This is the largest characterization of the disease in Canada to date.