scintillating scotoma

[sĭntl-ā′tĭng]
n.
  1. A localized area of blindness that may follow the appearance of brilliantly colored shimmering lights and is associated with the aura of migraine.
The American Heritage® Stedman's Medical Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Company. Published by Houghton Mifflin Company.