Any idea how large these images are? I seem to recall that
they are massive, given ultra-hi-rez data....

(Are they attaching them to lookOut mail ;-?)

And the radiologist may look for a few seconds at best so he
is NOT going to want to wait....

I just asked, and "you can video clip images,...85megs is typical"

Depends. They can also be small. I recently was given 1 hour to ship
X-rays and composite MRIs for a 2nd opinion. I was told by the
radiologist to take the printed pix, get a late model digital camera and
hold the pix up a window with no tree or electrical wires in the
background and no direct sunlight and take a digital picture. The 800K
files were sent via my home ADSL and worked quite well.