Digital anatomy - the body revealed - Science Photo Library

Feature Story 1184Digital anatomy - the body revealedThese beautiful and sometimes disturbing pictures represent the state-of-the-art in medical imaging. Made bySwiss radiologist Antoine Rosset, they show how the combination of modern technology and clever softwarecan reveal the human body in 3-D colour - with such fine resolution that even tiny blood vessels are visible.

Science Photo Library Feature Stories - Digital AnatomySome of Rosset’s subjects arehealthy volunteers. A sequenceof four images begins with afully-clothed woman. Subsequentimages reveal her musculature andvascular system; the final imageher skeleton. In another image, sheis seen from above, appearing tofly out of the frame. Other imagesare of accident victims and surgicalpatients. The head of a severelydeformedchild showsthe patchwork of facialreconstruction; a skiaccident patient liesswathed in bandages,with the outline of therespirator and suctiontube that allows himto breathe. And otherimages show individualorgans and body parts.This is the humanbody revealed in allits detail. Many of the imagesresemble anatomical drawingsfrom earlier times, where cadaverswould be dissected layer by layer.Today, medical science relies ontechnology to strip away the layersof the body, revealing the arteriesand muscles that lie just beneaththe skin; through the organs thatlie deeper within the body, to theskeleton itself.Antoine Rosset, M.D., is AssistantProfessor at the Radiology Departmentof the Geneva University Hospital,Switzerland. He is responsible forthe Hospital’s two CT scanners.CT - Computed Tomography - hasbecome one of the workhorses of today’smedical imaging. Introduced in1990, the technology has revolutionisedmedical imaging and diagnosis.Unlike conventional X-ray machines,CT scanners can ‘see’soft tissue, so they arecapable of making detailedvisualisations ofthe internal anatomyof the body.CT scanners use athin X-ray beam tocreate ‘slices’ of thepatient’s body. Theseslices are reconstructedby computer into3-D images. Coloursare assigned according to the abilityof body parts to block the X-ray beam- their ‘radiodensity’. Fat, for example,is less dense than muscle, which, inturn, is less dense than bone. So fatcan be assigned one colour; muscleanother. This ability to assign coloursto specific body structures - blood vessels,for example - makes it possiblefor doctors to highlight areas of interest.It also allows Antoine Rosset to

Science Photo Library Feature Stories - Digital Anatomycreate exquisitely coloured images.These images were producedby Rosset, using his ownvisualisation softwarecalled OsiriX. Rosset isa doctor, not a softwaredeveloper.But, he says,modernradiology ishighly computerised,andradiologistshave to be familiarwith boththe scanners and thesoftware:“It’s not like the TV seriesER, where the doctor looks atan X-ray on a light box,” he says.“All the images we work on areon computer.”As well as seeing soft tissue, modernCT scanners produce very highresolution images. Each slice can beas thin as 1 mm, which means thatimages can be incredibly detailed,resolving individual blood vessels. This,says Rosset, gives much better 3-Dimages - but at a price. As the scannersare becoming higher in resolution,they are also producing more and moredata, which needs powerful and expensivesoftware to turn into images. Only the largerhospitals can afford this software, so Rossetdecided to develop his own:“I was disappointed by the commercialsoftware,” he says. “Itwas very expensive. Thebest solution to have theperfect tool for my workwas to develop my ownsoftware.”OsiriX is the result. It isfreely-available over theInternet, is open-source,- so users can modify itthemselves - and can takedata from any scanner andturn it into high-resolution colour3-D images. It runs on Applecomputers only - another reasonwhy Rosset developed it, sincehe couldn’t find any commercialequivalent for the Mac - and alreadyhas several thousand users.The combination of today’s high-resolutionscanners and OsiriX - togetherwith Rosset’s eye and sense of aesthetics- have produced these stunning images.They are, quite simply, the state-ofthe-artin medical imaging.But, says Rosset, this will not always be thecase:“The evolution of CT will continue quickly.The next generation of CT scanners will producefaster, higher-resolution images. Medical imagingis rapidly evolving.”ENDS 700 WDS © SCIENCE PHOTO LIBRARY 2007

FULL PICTURE SETFor captions and credits, please refer to the captions.txt fileScience Photo Library Feature Stories - ????For further information, please contact: seymour@sciencephoto.comAll images are copyright, please credit images as stated on the captions

FULL PICTURE SETFor captions and credits, please refer to the captions.txt fileScience Photo Library Feature Stories - ????For further information, please contact: seymour@sciencephoto.comAll images are copyright, please credit images as stated on the captions