People have been able to look at the most intimate details of the Visible Woman since the National Library of Medicine made her available on the Internet in 1995. But most have never seen her in quite the way that they can with new software being released today.
Using new software that can be downloaded from the Pittsburgh Supercomputing Center, medical students, surgeons and other computer users now can view any part of the Visible Woman from virtually any angle. The interactive browser will allow users to navigate at will through her body, following the curve of her spine, if they choose, or circling around her heart.
Visible Woman, like her Visible Human male counterpart, is a digital reconstruction of a cadaver that was thoroughly X-rayed, scanned with CT and MRI machines and then sliced into thin sections and photographed. The result is a giant computerized database that provides detailed views of all of her organs, bones and other body parts.
But until now the Visible Humans could be viewed only in two-dimensional cross-sections, which didn't always make it easy to discern three-dimensional shapes and spatial relationships.
The new PSC Volume Browser, however, allows the database to be seen from any angle a viewer chooses. It also allows the user to warp the images so that curvy features such as the spine that normally wouldn't exist in a single plane can be viewed in a single image.
The tool, developed by the supercomputing center under subcontract to the University of Michigan with funding from the National Library of Medicine, is being touted as a boon for anatomy classes and for surgical planning.
"The amount of anatomy our students can learn is markedly enhanced by something like this," said Dr. Kathleen Ryan, associate director of medical education at the University of Pittsburgh School of Medicine. Medical students today, like most college students, often turn first to the Internet for information, she noted, and many already have taken note of the project through the University of Michigan's Web site.
It's not something that is going to replace dissection of cadavers anytime soon, however. Dissection labs "provide a visceral understanding about structure" not yet possible with virtual computer tools. Working with human cadavers also provides an opportunity to teach students respect for the dignity of the human body, she added.
But using the new browser should improve the students' comprehension of what they see in the dissection labs, Ryan said.
Though the browser will work on many Windows PCs and Apple Macs, Arthur Wetzel of the supercomputing center adds the caveat that most people might not want to try this at home.
"It requires a substantial Internet connection," explained Wetzel, a biomedical modeling expert. "You can try it at home (with a dial-up modem), but be patient."
The key to the project, he emphasized, is high-speed networking. The Visible Female dataset is huge -- 40 gigabytes, or 40 billion bytes -- but still small enough to fit on some PC disk drives. The problem comes when a user tries to navigate such a large database because the speed of the disk drive limits the speed of the program.
The approach the Pittsburgh and Michigan groups have taken is to use a supercomputer that can hold that giant database in its active memory and then allow users to interact with it over the Internet.
The initial version of the Volume Browser works with the Visible Female and with the Visible Mouse, a magnetic resonance microscopy database at Duke University.
More information, an image library, and a download of the Volume Browser are available at www.psc.edu/biomed/research/VH/PVB/
Byron Spice can be reached at bspice@post-gazette.com or 412-263-1578.
