Timeline of Medical Imaging
Imaging the inside of the body, from Röntgen's discovery of X-rays in 1895 through ultrasound, nuclear medicine, computed tomography, magnetic resonance imaging and positron emission tomography to an 11.7-tesla human brain scanner in 2024.
- Category
- Medicine & Health
- Events
- 31 events 1895 – 2024
- Generated
- by claude-opus-5-5
1895: Röntgen discovers X-rays
On November 8, Wilhelm Röntgen, professor of physics at the University of Würzburg, saw a barium platinocyanide screen glow near a discharge tube sealed in black card, and found that the unknown rays passed through flesh far more easily than through bone or metal. He photographed the bones of his wife Anna Bertha's hand, submitted "On a New Kind of Rays" to the Würzburg Physical-Medical Society on December 28, and in 1901 received the first Nobel Prize in Physics.
https://en.wikipedia.org/wiki/Wilhelm_R%C3%B6ntgen1896: Physicians put X-rays to clinical use within weeks
Doctors took up the rays as soon as the news spread. John Hall-Edwards in Birmingham, England, radiographed a needle in a colleague's hand on January 11, one of the earliest clinical uses, and on February 3 Gilman and Edwin Frost at Dartmouth College imaged a boy's broken wrist, often cited as the first clinical radiograph in the United States. Burns and hair loss among early users were reported within months.
https://en.wikipedia.org/wiki/Radiography#History1896: Fluoroscopes show X-ray images live
Experimenters soon built fluoroscopes, in which X-rays passing through the body lit a fluorescent screen so that bones and moving organs could be watched live. Thomas Edison's laboratory found that calcium tungstate gave a brighter screen; Edison abandoned X-ray work around 1903 after his glassblower Clarence Dally was gravely injured by repeated exposure, and Dally died in 1904.
https://en.wikipedia.org/wiki/Fluoroscopy1913: Coolidge introduces the hot-cathode X-ray tube
William D. Coolidge of the General Electric Research Laboratory described a tube in which a heated tungsten filament supplied the electrons in a high vacuum, unlike earlier gas tubes, which depended on ionizing the residual gas inside them and stayed in use into the 1920s. The new tube gave a steadier, more controllable beam, and its design remains the model for medical X-ray tubes.
https://en.wikipedia.org/wiki/X-ray_tube#Coolidge_tube_(hot_cathode_tube)1914 – 1918: Marie Curie sends X-ray units to the front
As director of the Red Cross Radiology Service in the First World War, Marie Curie equipped 20 vehicles carrying X-ray apparatus, nicknamed "petites Curies", and about 200 fixed radiology posts, so that surgeons could locate bullets and shrapnel and see broken bones. She and her daughter Irène worked near the front, and from 1916 she trained about 150 women as X-ray assistants.
https://en.wikipedia.org/wiki/Marie_Curie#World_War_I1927: Moniz images the blood vessels of the brain
Portuguese neurologist Egas Moniz, working in Lisbon with Pedro Almeida Lima, injected sodium iodide solution into the surgically exposed carotid artery and X-rayed the brain's arteries, locating a tumor by the vessels it displaced; he presented cerebral angiography in Paris in July, after trials in which a patient had died. From 1931 he used Thorotrast, a radioactive thorium dioxide agent later linked to liver cancers and leukemia decades after injection.
https://en.wikipedia.org/wiki/Cerebral_angiography1928: International X-ray and Radium Protection Committee founded
Burns, cancers and deaths among early X-ray and radium workers, including Birmingham's John Hall-Edwards, whose left arm was amputated at the elbow in 1908, led the second International Congress of Radiology in Stockholm to set up the committee. Renamed the International Commission on Radiological Protection (ICRP) in 1950, when its remit widened beyond medicine, it issues the recommendations on which radiation-protection rules worldwide are based.
https://en.wikipedia.org/wiki/International_Commission_on_Radiological_Protection1942: Dussik tries to image the brain with ultrasound
Austrian neurologist Karl Theo Dussik and his brother Friedrich, a physicist, passed ultrasound through the head between two transducers in a water bath and recorded patterns they took to be the brain's ventricles, a method they called hyperphonography. Tests in the early 1950s, including scans of an empty skull at the Massachusetts Institute of Technology, showed that the patterns came mostly from the skull, and medical ultrasound turned to pulse-echo methods.
https://en.wikipedia.org/wiki/Medical_ultrasound#History1953: Seldinger publishes a catheter technique for angiography
Swedish radiologist Sven Ivar Seldinger described in Acta Radiologica how to place a catheter in an artery through the skin: puncture the vessel with a needle, pass a flexible guidewire through it, withdraw the needle and slide the catheter over the wire. The technique avoided cutting down to the vessel and became the standard access method for catheter angiography, the image-guided treatments of interventional radiology and central venous lines.
https://en.wikipedia.org/wiki/Seldinger_technique1953: Edler and Hertz record the beating heart with ultrasound
On October 29, at Lund University in Sweden, cardiologist Inge Edler and physicist Carl Hellmuth Hertz recorded echoes from the moving walls of a patient's heart with an industrial ultrasonic reflectoscope borrowed from Siemens and modified to record its traces photographically. Their 1954 report began echocardiography, and the two shared the 1977 Lasker Clinical Medical Research Award for it.
https://en.wikipedia.org/wiki/Echocardiography1955 – 1957: Satomura applies Doppler ultrasound to the heart
Shigeo Satomura, a physicist at Osaka University working with hospital cardiologists, measured the Doppler shift of ultrasound reflected from the beating heart, reporting it in Japanese and then in the Journal of the Acoustical Society of America. With Ziro Kaneko he went on to detect blood flow through the skin, and the work led to Doppler echocardiography and vascular Doppler ultrasound.
https://en.wikipedia.org/wiki/Shigeo_Satomura1957: Anger builds the gamma camera
Hal Anger of the Donner Laboratory at the University of California, Berkeley, completed a scintillation camera that imaged a radioactive tracer's gamma rays across a whole region of the body at once, rather than point by point like earlier scanners. Paired from the 1960s with technetium-99m, which a generator devised at Brookhaven National Laboratory in 1958 made available on site, it became the most widely used instrument in nuclear medicine.
https://en.wikipedia.org/wiki/Gamma_camera1958: Donald shows ultrasound can diagnose abdominal masses
In The Lancet on June 7, Glasgow obstetrician Ian Donald, his colleague John MacVicar and engineer Tom Brown described a contact scanner, adapted from industrial flaw detectors, whose echoes told fluid-filled cysts from solid tumors. John Wild and John Reid in Minneapolis and Douglass Howry in Denver had made two-dimensional echo images earlier in the decade; Donald's group went on to measure fetal growth, and ultrasound became routine in obstetrics.
https://en.wikipedia.org/wiki/Ian_Donald1963: Cormack publishes the mathematics of computed tomography
Allan Cormack, a South African physicist who took up the problem in Cape Town in 1956 and later moved to Tufts University, showed in papers published in 1963 and 1964 how to reconstruct a cross-section's absorption of radiation from measurements along many lines through it. They drew almost no response; Johann Radon had solved the underlying mathematics in 1917, and Semyon Tetelbaum and Boris Korenblum in Kiev had proposed a reconstruction scheme in 1957.
https://en.wikipedia.org/wiki/Allan_MacLeod_Cormack1965: Gros and CGR build a dedicated mammography unit
At the request of Strasbourg radiologist Charles Gros, the French firm Compagnie Générale de Radiologie (CGR) built the Senographe, a breast X-ray unit whose molybdenum target and filter gave low-energy X-rays that showed soft tissue and fine calcifications; it went on sale in 1966. Raul Leborgne in Uruguay had introduced breast compression in 1949, and a New York trial begun in 1963 found fewer breast cancer deaths among women offered screening that included mammography.
https://en.wikipedia.org/wiki/Mammography#History1971: Damadian finds tumors give distinct magnetic resonance signals
Raymond Damadian of the State University of New York Downstate Medical Center reported in Science in March that the nuclear magnetic resonance (NMR) relaxation times of water in rat tumors were longer than in normal tissues, and proposed scanning the body for cancer; he patented the idea in 1974. Relaxation times proved too variable to diagnose cancer, but their differences between tissues became a basis of contrast in magnetic resonance imaging (MRI).
https://en.wikipedia.org/wiki/Raymond_Damadian1971: Hounsfield's CT scanner images its first patient
On October 1, at Atkinson Morley's Hospital in London, Godfrey Hounsfield of the British company Electric and Musical Industries (EMI) and neuroradiologist James Ambrose scanned a woman with a suspected brain tumor on Hounsfield's prototype computed tomography (CT) scanner, revealing a cyst in the frontal lobe. CT soon reduced the need for invasive studies such as pneumoencephalography; Hounsfield shared the 1979 Nobel Prize in Physiology or Medicine with Allan Cormack.
https://en.wikipedia.org/wiki/Godfrey_Hounsfield1973: Lauterbur makes images with magnetic field gradients
Paul Lauterbur, a chemist at Stony Brook University, showed in Nature in March that a magnetic field gradient makes the nuclear magnetic resonance (NMR) frequency of nuclei depend on their position, and reconstructed a cross-section of two thin tubes of ordinary water inside a tube of heavy water; he called the method zeugmatography. Peter Mansfield and Peter Grannell at the University of Nottingham independently published a gradient method in November.
https://en.wikipedia.org/wiki/Paul_Lauterbur1975: Washington University team builds a positron emission tomograph
Michel Ter-Pogossian, Michael Phelps, Edward Hoffman and Nizar Mullani at Washington University in St. Louis described the positron emission transaxial tomograph (PETT), which caught the paired gamma rays from positron annihilations in detectors around the patient and reconstructed cross-sections by computer. Positron imaging dated back to Gordon Brownell's work in Boston in the 1950s; the combination underlies modern positron emission tomography (PET).
https://en.wikipedia.org/wiki/Positron_emission_tomography#History1976: Fluorodeoxyglucose tracer is first given to human volunteers
Brookhaven National Laboratory chemists, among them Tatsuo Ido, Alfred Wolf and Joanna Fowler, made fluorine-18 fluorodeoxyglucose (FDG), a tracer based on Louis Sokoloff's deoxyglucose method for measuring glucose use, and in August Abass Alavi at the University of Pennsylvania injected it into two volunteers and imaged its uptake in the brain. FDG was later found to collect in many tumors and became the standard tracer for positron emission tomography (PET).
https://en.wikipedia.org/wiki/Fluorodeoxyglucose_(18F)1977: First human magnetic resonance images are made
Peter Mansfield and Andrew Maudsley at the University of Nottingham published a magnetic resonance image of a finger in March, and Mansfield described echo-planar imaging, the very fast method that later made functional magnetic resonance imaging feasible. In July Raymond Damadian's team in Brooklyn scanned the chest of his assistant Larry Minkoff point by point over several hours with their scanner Indomitable, and in December another Nottingham group published a cross-section of a wrist.
https://en.wikipedia.org/wiki/History_of_magnetic_resonance_imaging#Imaging1980: Aberdeen whole-body scanner begins imaging patients
A University of Aberdeen team led by John Mallard, with William Edelstein and James Hutchison, began scanning patients on its own whole-body magnetic resonance imaging (MRI) scanner, using spin-warp imaging, a version of the Fourier method proposed by Richard Ernst's group in Zurich in 1975. A scan of a cancer patient in August is often cited as the first clinically useful MRI, and Fourier methods became the basis of clinical scanners.
https://en.wikipedia.org/wiki/John_Mallard1989: Spiral CT scans whole volumes in one breath-hold
Willi Kalender and colleagues at Siemens in Erlangen, Germany, scanned while the patient table moved steadily through a continuously rotating computed tomography (CT) gantry, so the X-ray beam traced a helix, and devised an interpolation that removed the resulting artifacts. Spiral or helical scanning covered a whole body region in one breath-hold and, with multi-row detectors from the 1990s, made CT angiography and detailed three-dimensional images practical.
https://en.wikipedia.org/wiki/History_of_computed_tomography#Helical/Spiral_CT1990: Ogawa shows MRI can track blood oxygenation
Seiji Ogawa and colleagues at Bell Laboratories reported that deoxygenated hemoglobin darkens magnetic resonance images of the rat brain, a contrast they named blood-oxygen-level-dependent (BOLD). In 1992 three groups used it to map human brain activity without injections; it became the main form of functional magnetic resonance imaging (fMRI), which John Belliveau's group at Harvard had first shown in 1991 with an injected contrast agent.
https://en.wikipedia.org/wiki/Functional_magnetic_resonance_imaging1991: Fujimoto, Huang and Swanson demonstrate optical coherence tomography
David Huang, Eric Swanson, James Fujimoto and colleagues at the Massachusetts Institute of Technology and Harvard Medical School described optical coherence tomography (OCT), an optical counterpart of ultrasound using low-coherence near-infrared light and interferometry, with images of a retina and a coronary artery in vitro. Zeiss sold the first commercial OCT eye scanner in 1996, and the Lasker Foundation put ophthalmic OCT scans at about 30 million a year in 2023.
https://en.wikipedia.org/wiki/Optical_coherence_tomography1993: DICOM standard lets imaging devices share images
The American College of Radiology (ACR) and the National Electrical Manufacturers Association (NEMA), whose first joint image standard of 1985 linked devices point to point, issued a third version, renamed Digital Imaging and Communications in Medicine (DICOM), that ran over ordinary computer networks. With digital detectors such as Fuji's storage-phosphor plates of the 1980s, it underpinned the picture archiving and communication systems (PACS) that replaced film.
https://en.wikipedia.org/wiki/DICOM1998: Townsend and Nutt build a combined PET–CT scanner
A prototype built by physicist David Townsend and engineer Ronald Nutt, funded by the US National Cancer Institute, began clinical trials at the University of Pittsburgh Medical Center; it joined positron emission tomography (PET) and computed tomography (CT) in one machine so that metabolic and anatomical images lined up. Commercial PET–CT scanners followed by 2001, and combined PET and magnetic resonance imaging (MRI) systems in 2010.
https://en.wikipedia.org/wiki/PET%E2%80%93CT2003: Lauterbur and Mansfield win the Nobel Prize
The Nobel Prize in Physiology or Medicine went to Paul Lauterbur and Peter Mansfield for discoveries concerning magnetic resonance imaging (MRI), citing Lauterbur's use of field gradients and Mansfield's analysis of the signals and his fast echo-planar method; the Nobel Assembly put MRI examinations at more than 60 million a year. Raymond Damadian, whose 1971 tumor findings had prompted Lauterbur's work, protested his exclusion in full-page newspaper advertisements.
https://en.wikipedia.org/wiki/History_of_magnetic_resonance_imaging#2003_Nobel_Prize2018: FDA authorizes autonomous AI screening for diabetic retinopathy
In April the US Food and Drug Administration (FDA) authorized IDx-DR, artificial intelligence (AI) software that reports from retinal photographs whether more than mild diabetic retinopathy is present, with no clinician reading the images. In a trial of 900 people with diabetes it found about 87 percent of cases and correctly cleared about 91 percent of the rest; its developers called it the first autonomous AI diagnostic system the FDA had authorized.
https://en.wikipedia.org/wiki/Artificial_intelligence_in_healthcare#Ophthalmology2021: Photon-counting CT scanner cleared for clinical use
In September the US Food and Drug Administration (FDA) cleared Siemens Healthineers' NAEOTOM Alpha, the first photon-counting computed tomography (CT) scanner authorized for sale in the United States. Its cadmium telluride detectors convert each X-ray photon into an electrical pulse and sort photons by energy, instead of summing light from a scintillator. Energy discrimination allowed materials such as iodine and calcium to be distinguished.
https://en.wikipedia.org/wiki/Photon-counting_computed_tomography2024: Iseult scanner images the human brain at 11.7 tesla
In April the French Alternative Energies and Atomic Energy Commission (CEA) released the first images of living human brains from Iseult, a whole-body magnetic resonance imaging (MRI) scanner near Paris whose 11.7-tesla magnet produced a stronger field than any previously used for human imaging; most clinical scanners operated at 1.5 or 3 tesla. Safety tests on the volunteers appeared in Nature Methods in October, and the first functional brain scans at 11.7 tesla followed in 2026.
https://en.wikipedia.org/wiki/History_of_magnetic_resonance_imaging#Additional_techniques