MRI: http://www.cis.rit.edu/htbooks/mri/images/cover-hd.gif

X-Ray: http://www.imaginiscorp.com/graphics/xray-chest.gif

Ultrasound: http://home.hkstar.com/~joewoo/images/us27.jpg

Nuclear Medicine: http://www.nucmednet.com/Sifxnm2.jpg

Optics: http://rampages.onramp.net/~stevent/dsotm.html