Milestones in Medical Diagnosis and Diagnostic Imaging
Date Development or Discovery
c. 400 BC Disease concept introduced by Greek physician Hippocrates.
1612 Medical Thermometer devised by Italian physician Sanctorius
c. 1660 Light microscope developed by Dutch naturalist Antohj van
1810 Stethoscope invented by French physician Rene' Laennec.
1850 - Germ theory of disease proposed by French scientist Louis Pasteur 1900 and developed by German bacteriologist Robert Koch.
1895 X-rays discovered by German physicist Wilhelm Conrad Roentgen.
He also produced the first x-ray picture of the body (his wife's hand) in
1900 Chest x-ray, widespread use of the chest x-ray made early detection
of tuberculosis (which was the most common cause of death) a
1906 X-ray contrast medium. First contrast filled image of the renal system
1910 Barium sulfate introduction of as contrast agent for gastro-intestinal
1910-Theory of Radioactivity published by Marie Curie and investigation of 1912 x-ray radiation for patient therapy (e.g. treatment of cancer).
1906 Electrocardiograph (ECG) invented by Dutch physiologist Willem
Einthoven to monitor and record the electric signature of the heart.
1924 Radiographic imaging of the gallbladder, bile duct and blood vessels
for the first time.
1929 Cardiac catheterization first performed by Forssmann on himself.
c. 1932 Transmission electron microscope (TEM) constructed by German
scientists Max Knoll and Ernst Ruska.
1945 Coronary artery imaging. Visualization of (blood vessels that feed the
1950 Nuclear Medicine applied imaging the kidneys, heart, and skeletal
1955 X-ray Image Intensifier-Television units to allow dynamic x-ray
imaging of moving scenes. These fluoroscopic movies provided new
information of the beating heart and its blood vessels.
c. 1955 Panoramic x-ray images of the entire jaw and teeth.
1957 Fiber endoscopy pioneered by South African-born physician Basil
Hirschowitz at the University of Michigan.
1960 Ultrasound imaging is developed to look at the abdomen and kidneys,
fetal baby, carotid blood vessels and heart.
1970 X-ray mammography finds widespread application in imaging the
1972 Computed Tomography (CT) scanning invented by British engineer
Godfrey Hounsfield of EMI Laboratories, England, and South African
born physicist Allan Cormack of Tufts University, Massachusetts.
1975 Chronic villus sampling developed by Chinese gynecologists as an
aid to the early diagnosis of genetic disorders.
1976 Coronary Angioplasty was introduced by surgeon Andreas Gruentzig
at the University Hospital, Zurich, Switzerland. This technique uses x-
ray fluoroscopy to guide the compression of plaques and minimize the
dangerous constriction of the heart vessels.
1978 Digital radiography: the TV signal from the x-ray system is converted
to a digital picture which can then be enhanced for clearer diagnosis
and stored digitally for future review.
1980 Magnetic Resonance Imaging (MRI) of the brain was first done on a
clinical patient. MRI was developed by Paul Lauterbur and scientists
at Thorn-EMI Laboratories, England, and Nottingham University,
1984 3-Dimensional image processing using digital computers and CT or
MR data, three dimensional images of bones and organs were first
1985 Clinical Positron Emission Tomography (PET) scanning developed by
scientists at the University of California.
c. 1985 Clinical Networks were first implemented to allow digital diagnostic
images to be shared between physicians via computer network,
allowing a doctor in Boston to review a CT examination from a patient
in Beijing, China.
1989 Spiral CT allows fast volume scanning of an entire organ during a
single, short patient breath hold of 20 to 30 seconds. Spiral CT had
caused a renaissance in CT and lead the way tosignificant
developments like CT Angiography.
1989 MR Angiography developed and clinically available to allow non-
invasive imaging of the blood vessels without radiation or contrast
1993 Echo Planar MR Imaging (EPI) developed and clinically available to
allow MR systems to provide early detection of acute stroke. EPI also
makes possible functional imaging, for instance of brain activity
allowing doctors to investigate the function of different centers of the
1993 Open MRI Systems developed to allow MR scanning of severely
claustrophobic or obese patients who could not tolerate convention
MR imaging in a close bore system.