What Causes Recurring Bouts Of Focusing Problem Of Eyes?

I occasionally have trouble focusing my eyes; they don t seem to be working together. I can t focus both on a single point...like a face on the TV or a traffic sign. I can see fine but just can t coordinate the eyes. The visual field seems to fragmented...kinda like what happens when a DVD image breaks up into patches, but more dynamic...the fragments aren t fixed. I have no pain. The episodes last 5-10 minutes and vision returns to normal without headaches...no pain, no sagging face. I m thinking TIA but the symptoms don t match. I m 72, 5 7 165 lbs, very active...tennis, snow boarding, swim 2000 yards in an hour; no cholesterol problems, no high blood pressure.... que pasa?