Blood tests which included an autoimmune screen were positive for Anti-GQ1b antibodies

A 41-year-old female presents with double vision and difficult walking for the last 1 week. She says she has been falling a lot the past week and has double visions when looking left or right. She had a cold 4 weeks ago. On examination, one notes a wide based gait (ataxia), areflexia in the lower limbs and ophthalmoplegia in all directions. There were no other neurological deficits or systemic symptoms such as weight loss noted. Blood tests which included an autoimmune screen were positive for Anti-GQ1b antibodies. What is the most likely diagnosis?

Meningoencephalitis

Cerebral venous sinus thrombosis

Miller Fisher syndrome

Vasculitis

Paraneoplastic syndrome