Using Images from the Internet:

The Internet is an excellent source of health-related and other images and many images are freely available for the purposes of teaching, studying, presenting and other educational activities. The use of images, even for educational purposes, is governed by the stated terms of use of each website and subject to U.S. Copyright Law.

Permission may need to be obtained to use images in teaching and presenting, and utilizing images for the purpose of publication commonly necessitates permission from the publisher or copyright holder.