Short answers, pulled from the story.
Medical imaging is the technique and process of imaging the interior of a body for clinical analysis and medical intervention. It reveals internal structures hidden by skin and bones, helps diagnose and treat disease, and can represent the function of organs and tissues. It also establishes a database of normal anatomy and physiology so that abnormalities can be identified.
In 1972, engineer Godfrey Hounsfield from the British company EMI invented the X-ray computed tomography device for head diagnosis. By 1975, EMI had developed a CT device for the entire body. Hounsfield and physicist Allan Cormack received the Nobel Prize in Physiology or Medicine in 1979.
MRI uses powerful magnets to polarize and excite the hydrogen nuclei of water molecules in human tissue, producing a detectable signal that is spatially encoded into images. It relies on a strong static field typically between 1.5 and 3 teslas, gradient fields for spatial encoding, and a radio-frequency field. Unlike CT, MRI does not use ionizing radiation, but it carries risks from tissue heating and from implanted devices such as pacemakers.
By 2010, over 5 billion medical imaging studies had been conducted worldwide. In 2006, radiation exposure from medical imaging accounted for about 50% of total ionizing radiation exposure in the United States.
Positron emission tomography uses coincidence detection and a positron-emitting isotope such as fluorine-18, often combined with glucose as F18-fluorodeoxyglucose to mark metabolic activity. Single photon emission computed tomography injects a radioisotope such as thallium-201, technetium-99m, iodine-123, or gallium-67, whose gamma rays are captured by detectors surrounding the body. In both nuclear medicine techniques, the patient becomes the source of the radioactivity rather than the imaging device.
Protection of medical images varies by country. In the United States, the Copyright Office will not register medical imaging produced by X-rays, ultrasounds, or MRI, treating them as machine output, and no federal case law directly addresses the issue. In Germany the images receive related rights lasting 50 years after creation, while in the United Kingdom they are normally protected by copyright because of the skill, labour and judgement required.
Yes. In 2003, 3D visualization was a key resource for the famous but ultimately unsuccessful attempt by Singaporean surgeons to separate Iranian twins Ladan and Laleh Bijani. The same 3D equipment had been used previously for similar operations with great success.