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You ask a good question. It's a shame you got downvoted.

http://www.washingtonpost.com/wp-srv/national/horizon/jan99/...

> When the NLM advertised for bidders willing to cut a human body into thin slices and photograph each slice, there was far more interest than anyone anticipated. About 100 of the approximately 120 American medical schools, collaborating in various combinations, formed six consortia to apply for the contract.

> The field was narrowed to three. Each consortium was asked to submit pictures of slices, taken 1 millimeter apart, from the abdomen of an animal or human body. One millimeter is about the thickness of a dime. A committee of anatomists and radiologists then chose the best. The winning bidder was a consortium of institutions in Colorado, Texas and Maryland.

> The actual work on the cadavers – first a male, then a female – occurred at the University of Colorado Health Sciences Center in Denver. Under the direction of two scientists, Victor Spitzer and David Whitlock, the bodies first underwent head-to-toe CAT and MRI scans before being frozen solid.

> To make them easier to handle, the bodies then were cut into four pieces with a special saw. Each of the three cuts – separating the body into sections containing head, neck and thorax, abdomen and pelvis, thighs and knees, and legs, ankles and feet – lost only 1.5 mm of tissue, represented by black space in the stacked final images.

> It is more accurate to say that the cadavers were milled rather than sliced. The bodies were packed in dry ice and surrounded by a slurry of frozen alcohol at temperatures between minus 90 and minus 60 degrees Fahrenheit.

> Starting from one end of a body section, a rotary rasp ground down the tissue to a specified depth. In the male, this depth was 1 mm. In the anatomically more complicated female, it was .33 mm, providing three times as much detail.

> Each round of milling exposed a smooth, rock-hard surface in which the anatomical features were visible like the grain in a log. The surface then was photographed using both digital and conventional film cameras before removal of the next "cryosection."

> Each cycle required from three to 15 minutes to complete, and the Colorado team could do about 50 each day. The work was meticulous because, once the rasp started, there was no second chance. The tissue came off in a frozen powder, which was collected, stored and ultimately "cremated in a respectful manner," according to an NLM official.




> Starting from one end of a body section, a rotary rasp ground down the tissue to a specified depth

Interesting. So they did not preserve the slices, but rather ground off shavings little-by-little. I had envisioned the process similar to slicing meat at the deli.

Looking at the pictures in the article again, you can actually see that the cadaver was frozen in a liquid.




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