Articles
Articles are a collaborative effort to provide a single canonical page on all topics relevant to the practice of radiology. As such, articles are written and continuously improved upon by countless contributing members. Our dedicated editors oversee each edit for accuracy and style. Find out more about articles.
More than 200 results
Article
Raymond V Damadian
Raymond V Damadian (1936-2022) was a pioneer in the field of MRI and inventor of one of the first MRI scanners.
Early life
Raymond Vahan Damadian was born on 16 March 1936 in Forest Hills, New York City and was a child prodigy. He studied violin at the Juilliard School of Music for eight years...
Article
Mirror image artifact
Mirror image artifact in sonography is seen when there is a highly reflective surface (e.g. diaphragm) in the path of the primary beam.
The primary beam reflects from such a surface (e.g. diaphragm) but instead of directly being received by the transducer, it encounters another structure (e.g. ...
Article
Charles Thurstan Holland
Charles Thurstan Holland (1863-1941) was a pioneering radiologist who played a pivotal role in establishing radiology as a specialty in its own right.
Early life
Charles Thurstan Holland was born in Bridgwater, Somerset on 7 March 1863. He studied medicine at University College Hospital in...
Article
Gustav Bucky
Gustav Bucky (1880-1963) was a German-born, American radiologist who pioneered the development of anti-scatter grids in projectional radiography with his invention, the Bucky diaphragm.
Early life
Gustav Peter Bucky was born in the city of Leipzig, Germany on 3 September 1880 2,3,5. He had a k...
Article
Taurine
Taurine is one of the compounds examined in MR spectroscopy. It resonates at 3.4 ppm chemical shift. It is elevated in medulloblastomas.
Article
Tumor specific MRI contrast agents
Tumor specific MRI contrast agents are pharmaceuticals that are targeted to tumors, either specifically or nonspecifically. Monoclonal antibodies are targeted to specific tumors such as adenocarcinoma of the colon. Metalloporphyrins exhibit affinity for many tumor types including carcinoma, sarc...
Article
MRI sequence parameters
Listed in the table below are the most common acquisition parameters for commonly used MRI pulse sequences (in msec).
For a general introduction to these sequences please refer to MRI sequences (basic).
The specific parameters for any given study varies from one manufacturer to another, and fr...
Article
Law of Bergonié and Tribondeau
The law of Bergonie and Tribondeau is that the radiosensitivity of a biological tissue is directly proportional to the mitotic activity and inversely proportional to the degree of differentiation of its cells. This law underpins the field of radiation-oncology, although such a general law may no...
Article
Slew rate
Slew rate refers to the speed at which a gradient can be turned on and off, and is defined as the maximum gradient strength of the gradient divided by the rise time.
MR imaging is a product of magnetic field gradients which are created by magnetic gradient coils. The quality and performance of...
Article
Nephrogenic systemic fibrosis
Nephrogenic systemic fibrosis (NSF), also known as nephrogenic fibrosing dermopathy, occurs almost exclusively in patients with renal impairment and is associated with the administration of gadolinium-based contrast agents (GBCAs) used in MRI.
The American College of Radiology (ACR) has divide...
Article
Valence shell
The valence shell of an atom is the outermost shell of the electron cloud. It plays a large part in determining the chemical, thermal, optical and
electrical properties of the element. This occurs because it often not
full and movement of electrons may occur between it and a) electrons
from othe...
Article
T2 relaxation
T2 relaxation, also known as spin-spin relaxation or transverse relaxation, refers to the progressive dephasing of spinning dipoles resulting in decay in the magnetization in the transverse plane (Mxy). Following a radiofrequency pulse, this form of relaxation occurs with the time constant T2 (a...
Article
Inverse Fourier transformation
The inverse Fourier transform is a mathematical formula that converts a signal in the frequency domain ω to one in the time (or spatial) domain t.
A time domain signal f(t) is obtained by demodulating a frequency domain signal F(ω) using a special sinusoidal wave ejωt across all time (from nega...
Article
LumiFlow
LumiFlow is a postprocessing technique for color or power Doppler ultrasound, which produces a relief-like visualization of the depicted vasculature.
Physics
Lumiflow can be applied to both color and power Doppler imaging. It applies a shading with an artifical light source to create a three-...
Article
Myocardial mapping
Myocardial mapping or parametric mapping of the heart is one of various magnetic resonance imaging techniques, which has evolved and been increasingly used in the last decade for non-invasive tissue characterization of the myocardium 1-5. Unlike normal T1-, T2- or T2*- images, parametric mapping...
Article
Windmill artifact
In CT imaging, the windmill artifact is an image distortion in the axial plane, encountered during helical multidetector acquisitions. The telltale appearance is characterized by equally distanced bright streaks diverging from a focal high-density structure. The streaks seemingly rotate while sc...
Article
Dark-field radiography
Dark-field radiography is an emerging medical imaging technology. While conventional x-ray imaging is based on the differential attenuation of various organs and tissues, dark-field radiography utilizes ultra-small angle x-ray scattering similar to dark-field computed tomography.
Clinical appli...
Article
Citrate peak
Citrate is a compound examined in MR spectroscopy in the setting of possible prostate carcinoma. Citrate resonates at 2.6 ppm and is decreased in prostate cancer.
For more information go to: MR spectroscopy in prostate cancer
Article
Black boundary artifact
Black boundary artifact, also known as India ink artifact or type 2 chemical shift artifact, is an artificially-created black line located at fat-water interfaces such as those between muscle and fat. This results in a sharp delineation of the muscle-fat boundary lending the image an appearance ...
Article
Renal intraparenchymal acceleration time
Renal intraparenchymal acceleration time is a parameter used in assessing renal arterial stenosis on Doppler ultrasound. It is the time taken from the start of systole to peak systole.
normal range: a value of usually <0.07 seconds (<70 ms) is taken as being within normal limits 1
See also
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