The virtual body is the work of Sergey Makarov at the Worcester Polytechnic Institute in Massachusetts and his colleagues. They used software to help them stitch the thousands of images together, and the final model was checked by five doctors, each with a different medical specialism. “It needs to be anatomically correct,” says Makarov, who presented the work at the IEEE Engineering in Medicine and Biology Society meeting in Milan, Italy, last month.
Their phantom is the most detailed digital reconstruction of a whole human body ever to be pieced together. She has 231 tissue parts, ranging from windpipe to eyeballs, but is missing nose cartilage and 14 other bits of the body.
Other teams have created phantoms from MRI and CT scans of living volunteers, but the resolution is nowhere near as good. Entire body scans take several hours and any slight movements blur the image. The scans also lack colour, which is important for understanding different tissues, says Makarov.
“Sectioned color images allow you to distinguish virtually all the anatomical structures we are made of,” says Silvia Farcito at the Foundation for Research on Information Technologies in Society, based in Zurich, Switzerland, although she says that blood vessels tend to collapse in cadavers.
“They have ten times as much information as you’d get from an MRI scan,” says Fernando Bello, who develops simulations for medical procedures at Imperial College London. “It means the team will have much more information about organs and their structuring.”
The high resolution of the model makes it ideal for virtual experiments. Each of the woman’s tissues has a well-defined set of parameters, such as density and thermal conductivity. This makes it possible to compute the impact that radiation, for example, and various imaging techniques are likely to have on living tissues.
“The phantom gives us a great opportunity to study human tissues without having to do human studies, which are lengthy and expensive,” says Ara Nazarian, an orthopedic surgeon at Harvard Medical School who is collaborating with Makarov.