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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 edited by countless contributing members over a period of time. A global group of dedicated editors oversee accuracy, consulting with expert advisers, and constantly reviewing additions.

658 results found
Article

Standard triangle language

Standard triangle language (STL), is one of many file formats used for 3D printing. For biomedical 3D printing from DICOM files, DICOM files must undergo image post-processing including segmentation and then be turned into an appropriate file format for printing. Currently (2019) STL is the most...
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Standard uptake value

The standard uptake value (SUV), also known as standardized uptake value, is a simple way of determining activity in PET imaging, most commonly used in fluorodeoxyglucose (FDG) imaging. It is also known as the dose uptake ratio (DUR). As the name suggests it is a mathematically derived ratio of ...
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Starry sky artifact (MRI)

Starry-sky artifact in parallel imaging MRI (e.g. SENSE) is relatively common, and typically encountered as non-uniform distribution of image noise, typically affecting the center part of the image (being more distant from the surface coils) more than the superficial tissues. Note that many othe...
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Steady-state free precession MRI

Steady-state free precession MRI (SSFP) is a type of gradient echo MRI pulse sequence in which a steady, residual transverse magnetization (Mxy) is maintained between successive cycles. The sequence is noted for its superiority in dynamic/cine assessment of cardiac function. Discussion To unde...
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Step-and-shoot tomosynthesis (breast)

Step-and-shoot is a technology of image acquisition in digital breast tomosynthesis characterized by stop scanning at every single angle during images acquisition. Step-and-shoot technology allows advantages in microcalcifications conspicuity, spatial resolution, signal-to-noise Ratio improveme...
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Stochastic effects

Stochastic effects occur by chance and can be compared to deterministic effects which result in a direct effect. Cancer induction and radiation induced hereditary effects are the two main examples of stochastic effects. Models Cancer induction as a result of exposure to radiation is thought by...
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Strain elastography

Strain elastography (also known as tissue strain elastography/static elastography/compression elastography) is a developing form of ultrasound that assesses tissues' macroscopic structure through the strain modulus. This is different from normal B-mode grayscale ultrasound which characterizes a ...
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Structure of the atom

The structure of the atom is key to the majority of the techniques used in radiology, and a general understanding of atomic structure is worthwhile. The following is a simplified overview of the structure of the atom. Nucleus The composition of an atom is - in classical physics - principally ...
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Superb microvascular imaging (ultrasound)

Superb microvascular imaging (SMI) is a recently developed ultrasound imaging technique that aims to visualize low velocity and small diameter blood vessel flow. Unlike conventional color and power Doppler imaging, SMI can suppress noise caused by motion artifacts without removing the weak signa...
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Superparamagnetic iron oxide

Superparamagnetic iron oxides (SPIOs) are a class of MR contrast agents composed of nanoparticles of iron oxide crystals coated in carbohydrates. They are used to image vasculature and the liver via shortening T1 and T2/T2* relaxation times. The main agent currently used is ferumoxytol (Ferahem...
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Superparamagnetism

Superparamagnetic materials consist of individual domains of elements that have ferromagnetic properties in bulk. Their magnetic susceptibility is between that of ferromagnetic and paramagnetic materials.  The figure illustrates the effect of a superparamagnetic material (grey circle) on the ma...
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Surface coil

Surface coils are a type of receive-only radiofrequency coil used in MRI to receive the radiofrequency signal (transmitted by the body coil). Surface coils are small and are shaped so that they can be placed near the part of anatomy being imaged. By their nature, surface coils have good signal-t...
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Susceptibility weighted imaging

Susceptibility weighted imaging (SWI) is an MRI sequence that is particularly sensitive to compounds which distort the local magnetic field and as such make it useful in detecting blood products, calcium, etc. Physics SWI is a 3D high-spatial-resolution fully velocity corrected gradient-echo M...
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Synthetic MRI

Synthetic MRI is a technique that generates contrast weighted images based on measurements of tissue properties from a single acquisition. Basic principles With synthetic MRI, different contrast weighted images can be obtained based on quantifications of a single multiple dynamic and multiple...
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T1 mapping - myocardium

T1 mapping is a magnetic resonance imaging technique used to calculate the T1 time of a certain tissue and display them voxel-vice on a parametric map. It has been used for myocardial tissue characterization 1-6 and has been investigated for other tissues 5. T1 is the spin-lattice or longitudin...
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T1 rho

T1 rho, also known as T1ρ or "spin lock" ('ρ' is the symbol for the Greek letter rho), is an MRI sequence that is being developed for use in musculoskeletal imaging. At the moment it is mostly investigational and does not yet have widespread clinical use. The "rho" in the sequence name refers t...
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T1 values (1.5 T)

T1 values are a few hundred milliseconds (ms) for most tissues examined. The following are approximate T1 values (ms) of several tissues for B0 = 1.5 T fat = 260 liver = 500 muscle = 870 brain white matter = 780 brain grey matter = 920 CSF = 2500 Tissues that will have high signal on T1-...
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T1 weighted image

T1 weighted image (also referred to as T1WI or the "spin-lattice" relaxation time) is one of the basic pulse sequences in MRI and demonstrates differences in the T1 relaxation times of tissues. A T1WI relies upon the longitudinal relaxation of a tissue's net magnetization vector (NMV). Basicall...
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T2 mapping - myocardium

T2 mapping is a magnetic resonance imaging technique used to calculate the T2 times of a certain tissue and display them voxel-vice on a parametric map. It has been used for tissue characterization of the myocardium 1-5 and has been investigated for cartilage 6,7 and other tissues 4. The T2 tim...
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T2* mapping - myocardium

T2* mapping is a magnetic resonance imaging technique used to calculate the T2* time of tissue and display them voxel-vice on a parametric map. It is used for myocardial tissue characterization 1-4 and has been investigated for other tissues 5,6. Methodology T2* mapping is usually based on gra...
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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, w...
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T2* relaxation

T2* decay refers to an exponential decrease in Mxy  (i.e. signal strength) following the initial excitation pulse as a function of time constant T2*. A picture of the signal or free induction decay (FID) is shown on the right, occurring immediately after a 90o RF excitation pulse in a liquid pha...
Article

T2 shine through

T2 shine-through refers to high signal on DWI images that is not due to restricted diffusion, but rather to high T2 signal which 'shines through' to the DWI image. T2 shine through occurs because of long T2 decay time in some normal tissue. This is most often seen with subacute infarctions due ...
Article

T2 washout

T2 washout is a phenomenon encountered on diffusion weighted imaging (DWI) which results in DWI images (e.g. b = 1000) appearing normal despite abnormal ADC maps.  For the phenomenon to occur a particular combination of ADC and T2 signal intensity is required.  increased T2 signal facilitated...
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T2 weighted image

T2 weighted image (T2WI) is one of the basic pulse sequences on MRI. The sequence weighting highlights differences on the T2 relaxation time of tissues. Summary repetition time (TR): long echo time (TE): long flip angle: less important than with T1 weighting fat: intermediate-bright fluid:...
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Taurine

Taurine is one of the compounds examined in MR spectroscopy. It resonates at 3.4 ppm chemical shift. It is elevated in medulloblastomas.
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Tc-99m HMPAO labeled WBC

Tc-99m HMPAO (hexamethylpropyleneamine oxime) labeled WBC is one of the technetium radiopharmaceuticals used in WBC imaging. There are three potential radiochemical impurities in the 99mTc-HMPAO: a hydrophilic secondary complex, the free pertechnetate and the reduced 99mTc-hydrolyzate. 1The min...
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Tc-99m MAG3

Tc-99m MAG3 (mercaptoacetyltriglycine) is one of the technetium radiopharmaceuticals used in renal imaging. Due to favorable energy and dosimetric characteristics, MAG3 radiolabeled with technetium has replaced the iodide-131 Hippuran for the study of renal function (tubular secretion physiology...
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Tc-99m pertechnetate

Tc-99m pertechnetate (Na+ 99mTc O4-) is one of the technetium radiopharmaceuticals used in imaging of thyroid, colon, bladder and stomach. Technetium (99mTc) has eight oxidation states 6, from -1 to +7; specifically, the oxidation state of technetium in the pertechnetate anion (99mTcO4-) is +7....
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Tc-99m sulfur colloid

Technetium-99m sulfur colloid is one of the technetium radiopharmaceuticals. Characteristics photon energy: 140 keV physical half-life: 6 hours biological half-life normal distribution: liver: 85% spleen: 10% bone marrow: 5% excretion: hepatic target organ: liver, spleen pharmacokinet...
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Technetium 99m-methyl diphosphonate

Technetium 99m-methyl diphosphonate (99mTc MDP) is a radiotracer used in nuclear medicine especially for bone scintigraphy. Any disease process which results in extracellular fluid expansion will lead to accumulation of this tracer. Radionuclide profile photon energy: 140 keV physical half li...
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Temporal resolution

Temporal resolution relates to the duration of time for acquisition of a single frame of a dynamic process, i.e., cine imaging. Discussion The concept of temporal resolution is fundamental to cardiac CT and MRI, in which a rapidly beating heart is imaged over the order of milliseconds into mul...
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Temporal resolution (ultrasound)

Temporal resolution in ultrasound represents the extent to which an ultrasound system is able to distinguish changes between successive image frames over time (i.e. movement). Temporal resolution is chiefly determined by the image frame rate of the system (measured in Hertz), which may vary dep...
Article

Tesla (SI unit)

The tesla (symbol T) is the derived SI unit of magnetic flux density, which represents the strength of a magnetic field. One tesla represents one weber per square meter. The equivalent, and superseded, cgs unit is the gauss (G); one tesla equals exactly 10,000 gauss. Most current medical magnet...
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Texture analysis

Texture analysis is a non-invasive, mathematical method assessing the spatial heterogeneity of regions of interest in medical imaging, its primary application is in the assessment of tumors. Although not a new topic of research, the past decade has seen a significant resurgence of texture analys...
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Thallium-201 scintigraphy

Thallium-201 (Th-201) is a radiopharmaceutical used for scintigraphy, primarily of the myocardium. The element thallium is treated by the body as an analog of potassium; it is produced in a cyclotron by bombarding thallium-203 with protons. Characteristics thallium is a monovalent cation usua...
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Thermal index

The thermal index (TI) is intended as a measure of an ultrasound beam's thermal bioeffects. It is often displayed on ultrasound screens (along with the mechanical index). Absorption of sound waves may cause heating in tissue. The thermal index depends on: a measure of time-averaged acoustic p...
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Thermionic emission

Thermionic emission is the emission of electrons from a heated metal (cathode). This principle was first used in the Coolidge tube and then later in the modern day x-ray tubes. Before the discovery of the principle, gas tubes were used for x-ray production. The cathode has its filament circuit ...
Article

Thermoluminescent dosimeter

Thermoluminescent dosimeter (TLD) is a passive radiation detection device that is used for personal dose monitoring or to measure patient dose.  Parts plastic holder nickel-coated aluminum card with TLD discs the discs are made of a thermoluminescent material, commonly calcium sulphate doped...
Article

Thomas Edison

Thomas Edison (1847-1931) was a prolific inventor, considered by many to be the greatest inventor in American history. Edison holds over one thousand US patents; however, this article will focus on his work on fluoroscopy.  Early life and career Thomas Alva Edison was born on 11 February 1897 ...
Article

Thoracic spine protocol (CT)

The CT thoracic spine or T-spine protocol serves as an examination for the assessment of the thoracic spine. As a separate examination, it is often performed as a non-contrast study. It might be combined or simultaneously acquired with a CT chest or CT chest-abdomen-pelvis as part of a trauma or...
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Thorotrast

Thorotrast is a suspension of radioactive thorium dioxide first produced in Germany in 1928 and used as a contrast agent until the 1950s. Its principal use was for cerebral angiography: 90% of the estimated 50,000-100,000 patients treated received it for this purpose. Umbrathor was another thori...
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Thyroid scan (Tc-99m)

Tc-99m pertechnetate thyroid scan is a functional nuclear medicine study used to assess the thyroid gland. The uptake of the pertechnetate anion - similar in chemical-physical characteristics to the iodide ion - in the thyroid parenchyma is mediated by the NIS (Sodium-Iodide Symporter). However,...
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Time gain compensation

A way to overcome ultrasound attenuation is time gain compensation (TGC), in which signal gain is increased as time passes from the emitted wave pulse. This correction makes equally echogenic tissues look the same even if they are located in different depths. The basis of this is that of return...
Article

Time of flight angiography

Time of flight angiography (TOF) is an MRI technique to visualize flow within vessels, without the need to administer contrast. It is based on the phenomenon of flow-related enhancement of spins entering into an imaging slice. As a result of being unsaturated, these spins give more signal than s...
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Time to peak (TTP)

Time-to-peak (TTP) is the time at which contrast concentration reaches its maximum. For example, for a particular dynamic susceptibility contrast (DSC) imaging acquisition in which images are acquired every 1.5 seconds, possible TTP values could include 20.0 seconds, 21.5 seconds, 23.0 seconds, ...
Article

Tissue Doppler imaging (echocardiography)

A variant of pulsed wave Doppler, tissue Doppler imaging (TDI) is a modality in echocardiography that allows measurement of the velocity of myocardial movement throughout the cardiac cycle. Physics Color flow, pulsed wave, and continuous wave Doppler are designed to analyze the Doppler shifts ...
Article

Tissue to background ratio

The tissue to background ratio is a measure of the specificity of radiopharmaceutical uptake within the target organ in a nuclear medicine study. It is also referred to as tumor to background ratio in the literature. The presence of radiopharmaceutical in the background (tissues external to the...
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Tissue weighting factor

The tissue weighting factor (WT) is a relative measure of the risk of stochastic effects that might result from irradiation of that specific tissue. It accounts for the variable radiosensitivities of organs and tissues in the body to ionizing radiation. To calculate the effective dose, the indi...
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Training, testing and validation datasets

The division of the input data into training, testing and validation sets is crucial in the creation of robust machine learning algorithms. Firstly, machine learning algorithms require a training set to be trained on. Each iteration, it calculates the difference between the predicted and actual ...
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Transducer-related artifact

Artifacts in ultrasound imaging may result from faults in the transducer itself or in the transducer cable. 
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Transformer

A transformer is a passive electrical device used to transfer electrical energy from one circuit to another, via the phenomenon of electromagnetic induction. It is fundamental in the modulation of voltage and current in the x-ray generator. Components primary coil a set of insulated wires at...
Article

Transient elastography

Transient elastography most often refers to a type of elastography which relies on a mechanical pulse generated by an external probe. The principle is similar to shear wave elastography, in that the elastic modulus is generated from shear wave velocity, but the application of the pulse from an ...
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Transient interruption of contrast

Transient interruption of contrast (TIC) is a common flow artifact seen in CT pulmonary angiography (CTPA) studies. The contrast opacificiation of the pulmonary arteries is suboptimal due to an increase in the flow of unopacified blood from the inferior vena cava (IVC) to the right side of the h...
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Transmutation

Nuclear transmutation occurs when a decay process alters the number of protons in a nucleus to form a new element. Processes which cause nuclear transmutation include beta particle emission, alpha particle emission, and electron capture.
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Truncation artifact (CT)

Truncation artifact in CT is an apparently increased curvilinear band of attenuation along the edge of the image. This artifact is encountered when parts of the imaged body part remain outside the field of view (e.g. due to patient body habitus), which results in inaccurate measurement of atten...
Article

Tube arcing

Tube arcing occurs when there is a short-circuit within the tube, typically from the cathode to the tube envelope. The result is a temporary loss of x-ray output and a localized artefact.  A number of causes of tube arcing are recognized 1:  insulator surface flashover insulator breakdown va...
Article

Tube current modulation

Tube current modulation is a feature of modern CT scanners to alter the strength of the beam by modulating the current of the x-ray tube depending on the signal to noise ratio. The purpose of tube current modulation is to maintain a near constant signal to noise ratio in the image across differe...
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Tube rating

Tube ratings are the defined input parameters (kVp, mA, exposure) that can be safely used during its operation without causing damage to the x-ray tube itself and unique to each individual x-ray tube model. An x-ray tube rating is the maximum allowable kilowatts (kW) in 0.1 second 2.  When the ...
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Tube shielding

Tube shielding refers to the use of a material within the X-ray tube housing to limit leakage of scattered radiation, to protect both patients and staff from unnecessary exposure. Lead (Pb) is an ideal material for this purpose due to its high atomic density (Z = 82). Due to these properties, i...
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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...
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Tungsten

Tungsten (chemical symbol, W) is a hard refractory metallic element with remarkable resilience which forms the basis for its industrial uses. It is the metal of choice in the filaments and targets of x-ray tubes. There is no evidence that tungsten is required by the human body, although some mic...
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Turbo inversion recovery magnitude

Turbo inversion recovery magnitude (TIRM) is an inversion recovery MRI pulse sequence that displays the magnitude of a turbo/fast spin echo, without regard for the phase/polarity of the longitudinal magnetization. This method of image reconstruction is the dominant form of inversion recovery use...
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Twinkling artifact

Twinkling artifact is seen with color flow Doppler ultrasound 1. It occurs as a focus of alternating colors on Doppler signal behind a reflective object (such as a calculus), which gives the appearance of turbulent blood flow 2. It appears with or without an associated color comet-tail artifact ...
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Ultrahigh field MRI

Ultrahigh field (UHF) magnetic resonance imaging refers to imaging done on any MRI scanner with a main magnetic field (B0) strength of 7 tesla or greater. Until recently purely a research tool, following the introduction of the first 7 T clinical scanner in 2017, there are now a slowly increasin...
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Ultrasound artifacts

Ultrasound artifacts are commonly encountered and familiarity is necessary to avoid false diagnoses. They are not to be confused with ultrasound probe defects, which represent hardware failure.  Artifacts acoustic enhancement acoustic shadowing aliasing artifact anisotropy bayonet artifact...
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Ultrasound elastography

Ultrasound elastography, also called as sono-elastography, is a modern evolutionary method of sonographic imaging. Techniques include shear wave elastography (also known as transient elastography) and strain elastography (also known as static or compression elastography). These techniques utiliz...
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Ultrasound frequencies

Ultrasound frequencies in diagnostic radiology range from 2 MHz to approximately 15 MHz.  It is important to remember that higher frequencies of ultrasound have shorter wavelengths and are absorbed/attenuated more easily. Therefore, higher frequencies are not as penetrating. This explains why h...
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Ultrasound (introduction)

Ultrasound (US) is an imaging technology that uses high-frequency sound waves to characterize tissue. It is a useful and flexible modality in medical imaging, and often provides an additional or unique characterization of tissues, compared with other modalities such as conventional radiography o...
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Ultrasound probe defect

Ultrasound probe defects are hardware failures of the ultrasound transducer manifesting as various abnormalities of the scan image, in severe cases even causing complete signal loss. These are a form of ultrasound artifact. Therefore, awareness of the various signs of equipment damage is crucia...
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Ultrasound transducer

An ultrasound transducer converts electrical energy into mechanical (sound) energy and back again, based on the piezoelectric effect. It is the hand-held part of the ultrasound machine that is responsible for the production and detection of ultrasound waves. It consists of five main components:...
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Units of measurement

For units of measurement the use of SI units (both base and derived units) in articles and cases on Radiopaedia.org is preferred. This is in line with best scientific practice and helps maintain consistency across the site. Terminology By scientific convention: for eponymous units, the full ...
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 o...
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Velocity encoding

Velocity encoding or Venc is referred to as an operator-controlled parameter for the determination of the maximum velocity within a velocity encoded phase contrast imaging study. Usage Velocity-encoding (Venc) gradients are used to generate a phase shift in magnetic resonance phase contrast im...
Article

Vicarious contrast media excretion

Vicarious contrast media excretion (VCME) is defined as excretion of intravascularly-administered water-soluble contrast media in a way other than via normal renal excretion. The most common vicarious excretion of water-soluble contrast material is via the liver, resulting in increased bile dens...
Article

Virtual reality

Advancements of technology have enabled various simulated reality devices, including virtual reality (VR) and augmented reality (AR). Both technologies provide stereoscopic and three-dimensional (3D) immersion of a simulated object. VR simulates a virtual environment while AR overlays simulated ...
Article

Volume coils

Volume coils are the transmit and receive radiofrequency coils which are used to both transmit and receive the radiofrequency signal in MRI. Most MRI scanners have what is called a body coil – which is a volume coil built into the bore of the magnet which transmits the radiofrequency for most ex...
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Volume rendering

Volume rendering is a type of data visualization technique which creates a three-dimensional representation of data. CT and MRI data are frequently visualized with volume rendering in addition to other reconstructions and slices.  This technique can also be applied to tomosynthesis data. Volume ...
Article

Voxel

Voxel is a portmanteau of contractions of the two words 'volume' and 'element' and was coined as a 3-D equivalent of a pixel. It is an individual point in space on a 3-dimensional, regular matrix. The location of each voxel is encoded by its relative relationship to other voxels. A tensor may b...
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Voxel size

Voxel size is an important component of image quality. Voxel is the 3-D analog of a pixel. Voxel size is related to both the pixel size and slice thickness.  Pixel size is dependent on both the field of view and the image matrix. The pixel size is equal to the field of view divided by the matrix...
Article

Wall filter

The wall filter in ultrasound is a way of filtering out low or high frequency Doppler signals. In clinical ultrasound, it is usually used to filter out very low frequencies that may add noise to a spectral Doppler waveform. A typical use is removing the low frequency reverberation of an arteria...
Article

Weber (SI unit)

The weber (symbol: Wb) is the SI derived unit of magnetic flux, and superseded the maxwell, the CGS unit for magnetic flux.  Terminology As per all other eponymous SI units when the unit is written out in full it is not capitalized, but when shortened to its symbol it is capitalized. History ...
Article

Wilhelm Roentgen

Wilhelm C Roentgen (1845-1923) was a German physicist who is celebrated globally for his discovery of x-rays on 8 November 1895. Early life Wilhelm Conrad Roentgen (Röntgen in German) was born on 27 March 1845 in Lennep, Germany. He attended the primary and secondary school run by Martinus Her...
Article

William D Coolidge

William D Coolidge (1873-1975) was an American physicist who revolutionised radiology with his groundbreaking x-ray tube, the underlying technology of which remains at the core of every machine more than a century later. Early life William David Coolidge was born on 23 October 1873 on a small ...
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

Wrist protocol (MRI)

The MRI wrist protocol encompasses a set of MRI sequences for the routine assessment of the wrist joint. Note: This article aims to frame a general concept of an MRI protocol for the assessment of the wrist. Protocol specifics will vary depending on MRI scanner type, specific hardware and softw...
Article

Xenon-127

Xenon-127 is a radiopharmaceutical principally used when a performing VQ scan. It is not a widely used alternative to xenon-133 with the main advantage being a higher proton energy allowing for post perfusion scanning.  photon energy: 203 KeV physical half life: 36.3 days
Article

X-ray artifacts

X-ray artifacts can present in a variety of ways including abnormal shadows noted on a radiograph or degraded image quality, and have been produced by artificial means from hardware failure, operator error and software (post-processing) artifacts.  There are common and distinct artifacts for fi...
Article

X-ray film

X-ray film displays the radiographic image and consists of emulsion (single or double) of silver halide (silver bromide (AgBr) is most common) which when exposed to light, produces a silver ion (Ag+) and an electron. The electrons get attached to the sensitivity specks and attract the silver ion...
Article

X-ray interaction with matter

X-rays in the diagnostic range interact with matter primarily via two major processes, which are fundamental in understanding how an image is formed in a radiographic exam. These processes are the: photoelectric effect  Compton scatter 
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X-ray production

X-rays are produced due to sudden deceleration of fast-moving electrons when they collide and interact with the target anode. In this process of deceleration, more than 99% of the electron energy is converted into heat and less than 1% of energy is converted into x-rays. Definitions Generator ...
Article

X-ray quantity and quality

X-ray photon quantity refers to the number of photons produced during an exposure. Factors influencing x-ray quantity includes: peak voltage (kVp): beam quantity is approximately proportional to the square of the tube potential generator type/voltage waveform: reducing ripple increases beam q...
Article

X-rays

X-rays (or much more rarely, and usually historically, x-radiation or Roentgen rays) represent a form of ionizing electromagnetic radiation. They are produced by an x-ray tube, using a high voltage to accelerate the electrons produced by its cathode. The produced electrons interact with the anod...

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