Saw rotating "barber's pole" black & white pattern out of corner of left eye for 2 secs. Another ocular migraine? Looked to that side, it was gone.

Maybe. Your typical visual hallucinations from acephalic migrains usually last 10 to 15 minutes. However, not everyone has textbook symptoms. Vitreous pulling on the retina could cause visual symptoms as well, which uncommonly can lead to retinal detachment. I would get a full dilated eye exam.
Ocular migraine. What you describe sounds like an ocular migraine. Any type of flashing, waving, or rotating lights or patterns are common visual disturbances of ocular migraine. If a person has ocular migraines without a headache; these can be distressing, but one can learn to understand and disregard them. For more info on migraines see: http://understandingmigraine. Blogspot. Com/