Hi there,
Rather than rewriting a bit, let me refer you to what I wrote in this thread: http://www.healingwell.com/community/default.aspx?f=31&m=1320097
As you've encountered, visual distortions are usually associated with aura wen it comes to migraine. But it could be an actual optical/eye problem. IIH (see my post) is always something that should be considered in the case of actual visual deficiency--the blind spots that you mentioned are not typically a part of visual aura. However, trouble reading can easily be explained by cognitive deficiency (like problems with concentration or attention) that often is a side effect of migraines.
Regardless, definitely see a doctor.
Ben
DX: NDPH, Recovered CRPS
RX: Lamictal, Provigil, Clonazepam, Ambien CR, Emsam, Namenda, Oxycontin, Oxycodone
PRN: Haloperidol, Zyprexa, Lodine, Zofran, Skelaxin