Question: You are asked to provide recommendations for a patient with acute vertigo with nystagmus and associated vomiting and dehydration. Upon examination you find that the fast phase of nystagmus is rightward and occurs in all directions of gaze. The nystagmus is suppressed partially with visual fixation. There is no associated hearing loss. What is the most likely diagnosis and what grade of nystagmus does this represent, according to Alexander's law? [Answer will be posted with next week's new question]

Answer to last week's question, "A Rush Of Blood To The Head" (May 8, 2017)

Pterygopalatine fossa, or pterygomaxillary fissure.