A report on X-ray

Natural color x-ray photogram of a wine scene

Example of a Crookes tube, a type of discharge tube that emitted X-rays

Hand mit Ringen (Hand with Rings): print of Wilhelm Röntgen's first "medical" X-ray, of his wife's hand, taken on 22 December 1895 and presented to Ludwig Zehnder of the Physik Institut, University of Freiburg, on 1 January 1896

Taking an X-ray image with early Crookes tube apparatus, late 1800s. The Crookes tube is visible in center. The standing man is viewing his hand with a fluoroscope screen. The seated man is taking a radiograph of his hand by placing it on a photographic plate. No precautions against radiation exposure are taken; its hazards were not known at the time.

Surgical removal of a bullet whose location was diagnosed with X-rays (see inset) in 1897

Images by James Green, from "Sciagraphs of British Batrachians and Reptiles" (1897), featuring (from left) Rana esculenta (now Pelophylax lessonae), Lacerta vivipara (now Zootoca vivipara), and Lacerta agilis

1896 plaque published in "Nouvelle Iconographie de la Salpetrière", a medical journal. In the left a hand deformity, in the right same hand seen using radiography. The authors named the technique Röntgen photography.

A patient being examined with a thoracic fluoroscope in 1940, which displayed continuous moving images. This image was used to argue that radiation exposure during the X-ray procedure would be negligible.

Chandra's image of the galaxy cluster Abell 2125 reveals a complex of several massive multimillion-degree-Celsius gas clouds in the process of merging.

X-rays are part of the electromagnetic spectrum, with wavelengths shorter than UV light. Different applications use different parts of the X-ray spectrum.

Attenuation length of X-rays in water showing the oxygen absorption edge at 540 eV, the energy−3 dependence of photoabsorption, as well as a leveling off at higher photon energies due to Compton scattering. The attenuation length is about four orders of magnitude longer for hard X-rays (right half) compared to soft X-rays (left half).

Spectrum of the X-rays emitted by an X-ray tube with a rhodium target, operated at 60 kV. The smooth, continuous curve is due to bremsstrahlung, and the spikes are characteristic K lines for rhodium atoms.

Patient undergoing an x-ray exam in a hospital radiology room.

A chest radiograph of a female, demonstrating a hiatal hernia

Head CT scan (transverse plane) slice – a modern application of medical radiography

Abdominal radiograph of a pregnant woman, a procedure that should be performed only after proper assessment of benefit versus risk

$Each dot, called a reflection, in this diffraction pattern forms from the constructive interference of scattered X-rays passing through a crystal. The data can be used to determine the crystalline structure.$

Using X-ray for inspection and quality control: the differences in the structures of the die and bond wires reveal the left chip to be counterfeit.

Penetrating form of high-energy electromagnetic radiation.

- X-ray

121 related topics with Alpha

Electromagnetic radiation

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In physics, electromagnetic radiation (EMR) consists of waves of the electromagnetic (EM) field, propagating through space, carrying electromagnetic radiant energy.

Shows the relative wavelengths of the electromagnetic waves of three different colours of light (blue, green, and red) with a distance scale in micrometers along the x-axis.

In electromagnetic radiation (such as microwaves from an antenna, shown here) the term "radiation" applies only to the parts of the electromagnetic field that radiate into infinite space and decrease in intensity by an inverse-square law of power, so that the total radiation energy that crosses through an imaginary spherical surface is the same, no matter how far away from the antenna the spherical surface is drawn. Electromagnetic radiation thus includes the far field part of the electromagnetic field around a transmitter. A part of the "near-field" close to the transmitter, forms part of the changing electromagnetic field, but does not count as electromagnetic radiation.

Electromagnetic waves can be imagined as a self-propagating transverse oscillating wave of electric and magnetic fields. This 3D animation shows a plane linearly polarized wave propagating from left to right. The electric and magnetic fields in such a wave are in-phase with each other, reaching minima and maxima together.

Representation of the electric field vector of a wave of circularly polarized electromagnetic radiation.

Electromagnetic spectrum with visible light highlighted

Rough plot of Earth's atmospheric absorption and scattering (or opacity) of various wavelengths of electromagnetic radiation

It includes radio waves, microwaves, infrared, (visible) light, ultraviolet, X-rays, and gamma rays.

Gamma ray

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Penetrating form of electromagnetic radiation arising from the radioactive decay of atomic nuclei.

Image of entire sky in 100 MeV or greater gamma rays as seen by the EGRET instrument aboard the CGRO spacecraft. Bright spots within the galactic plane are pulsars while those above and below the plane are thought to be quasars.

A hypernova. Artist's illustration showing the life of a massive star as nuclear fusion converts lighter elements into heavier ones. When fusion no longer generates enough pressure to counteract gravity, the star rapidly collapses to form a black hole. Theoretically, energy may be released during the collapse along the axis of rotation to form a long duration gamma-ray burst.

Alpha radiation consists of helium nuclei and is readily stopped by a sheet of paper. Beta radiation, consisting of electrons or positrons, is stopped by an aluminium plate, but gamma radiation requires shielding by dense material such as lead or concrete.

The total absorption coefficient of aluminium (atomic number 13) for gamma rays, plotted versus gamma energy, and the contributions by the three effects. As is usual, the photoelectric effect is largest at low energies, Compton scattering dominates at intermediate energies, and pair production dominates at high energies.

The total absorption coefficient of lead (atomic number 82) for gamma rays, plotted versus gamma energy, and the contributions by the three effects. Here, the photoelectric effect dominates at low energy. Above 5 MeV, pair production starts to dominate.

Gamma-ray image of a truck with two stowaways taken with a VACIS (vehicle and container imaging system)

In practice, gamma ray energies overlap with the range of X-rays, especially in the higher-frequency region referred to as "hard" X-rays. This depiction follows the older convention of distinguishing by wavelength.

The Moon as seen by the Compton Gamma Ray Observatory, in gamma rays of greater than 20 MeV. These are produced by cosmic ray bombardment of its surface. The Sun, which has no similar surface of high atomic number to act as target for cosmic rays, cannot usually be seen at all at these energies, which are too high to emerge from primary nuclear reactions, such as solar nuclear fusion (though occasionally the Sun produces gamma rays by cyclotron-type mechanisms, during solar flares). Gamma rays typically have higher energy than X-rays.

It consists of the shortest wavelength electromagnetic waves, typically shorter than those of X-rays.

Alpha (α) radiation consists of a fast-moving helium-4 (Helium-4) nucleus and is stopped by a sheet of paper. Beta (β) radiation, consisting of electrons, is halted by an aluminium plate. Gamma (γ) radiation, consisting of energetic photons, is eventually absorbed as it penetrates a dense material. Neutron (n) radiation consists of free neutrons that are blocked by light elements, like hydrogen, which slow and/or capture them. Not shown: galactic cosmic rays that consist of energetic charged nuclei such as protons, helium nuclei, and high-charged nuclei called HZE ions.

Ionizing radiation

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Ionizing radiation (or ionising radiation), including nuclear radiation, consists of subatomic particles or electromagnetic waves that have sufficient energy to ionize atoms or molecules by detaching electrons from them.

Cloud chambers are used to visualise ionizing radiation. This image show the tracks of particles, which ionise saturated air and leave a trail of water vapour.

Different types of electromagnetic radiation

The total absorption coefficient of lead (atomic number 82) for gamma rays, plotted versus gamma energy, and contributions by the three effects. The photoelectric effect dominates at low energy, but above 5 MeV, pair production starts to dominate.

Radiation interaction: gamma rays are represented by wavy lines, charged particles and neutrons by straight lines. The small circles show where ionization occurs.

Ionized air glows blue around a beam of particulate ionizing radiation from a cyclotron

Relationship between radioactivity and detected ionizing radiation. Key factors are; strength of the radioactive source, transmission effects and instrument sensitivity

Radiation level in a range of situations, from normal activities up to the Chernobyl reactor accident. Each step up the scale indicates a tenfold increase in radiation level.

Various doses of radiation in sieverts, ranging from trivial to lethal.

2007 ISO radioactivity danger symbol intended for IAEA Category 1, 2 and 3 sources defined as dangerous sources capable of death or serious injury.

Gamma rays, X-rays, and the higher energy ultraviolet part of the electromagnetic spectrum are ionizing radiation, whereas the lower energy ultraviolet, visible light, nearly all types of laser light, infrared, microwaves, and radio waves are non-ionizing radiation.

Fluoroscopy

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A fluoroscopy X-ray machine is a great asset during surgery for implants

A barium swallow exam taken via fluoroscopy.

Experimenter in 1890s (top right) examining his hand with fluoroscope.

Thoracic fluoroscopy using handheld fluorescent screen, 1909. No radiation protection is used, as the dangers of X-rays were not yet recognised.

Surgical operation during World War I using a fluoroscope to find embedded bullets, 1917.

Adrian shoe-fitting fluoroscope used prior to 1950 in shoe stores for testing the fit of shoes. A high-tech sales gimmick, these were phased out due to concerns about unnecessary radiation exposure.

Fluoroscopy is an imaging technique that uses X-rays to obtain real-time moving images of the interior of an object.

Radiography

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Acquisition of projectional radiography, with an X-ray generator and a detector.

Images generated from computed tomography, including a 3D rendered image at upper left.

Angiogram showing a transverse projection of the vertebro basilar and posterior cerebral circulation.

Radiography may also be used in paleontology, such as for these radiographs of the Darwinius fossil Ida.

Taking an X-ray image with early Crookes tube apparatus, late 1800s

1897 sciagraph (X-ray photograph) of Pelophylax lessonae (then Rana Esculenta), from James Green & James H. Gardiner's "Sciagraphs of British Batrachians and Reptiles"

Radiography is an imaging technique using X-rays, gamma rays, or similar ionizing radiation and non-ionizing radiation to view the internal form of an object.

Wilhelm Röntgen

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Birthplace of Röntgen in Remscheid-Lennep

Wall art by the house where Wilhelm Röntgen lived in from 1863 until 1865 in the Schalkwijkstraat in Utrecht. Made by Jackie Sleper in 2005.

Grave of Wilhelm Röntgen at Alter Friedhof (old cemetery) in Gießen

First medical X-ray by Wilhelm Röntgen of his wife Anna Bertha Ludwig's hand

Wilhelm Conrad Röntgen (27 March 1845 – 10 February 1923) was a German mechanical engineer and physicist, who, on 8 November 1895, produced and detected electromagnetic radiation in a wavelength range known as X-rays or Röntgen rays, an achievement that earned him the inaugural Nobel Prize in Physics in 1901.

Light

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Electromagnetic radiation within the portion of the electromagnetic spectrum that is perceived by the human eye.

The electromagnetic spectrum, with the visible portion highlighted

Beam of sun light inside the cavity of Rocca ill'Abissu at Fondachelli-Fantina, Sicily

$Due to refraction, the straw dipped in water appears bent and the ruler scale compressed when viewed from a shallow angle.$

Hong Kong illuminated by colourful artificial lighting.

$Thomas Young's sketch of a double-slit experiment showing diffraction. Young's experiments supported the theory that light consists of waves.$

In this sense, gamma rays, X-rays, microwaves and radio waves are also light.

X-ray tube

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Crookes X-ray tube from early 1900s. The cathode is on the right, the anode is in the center with attached heat sink at left. The electrode at the 10 o'clock position is the anticathode. The device at top is a 'softener' used to regulate the gas pressure.

Simplified rotating anode tube schematic

Two high Voltage rectifier tubes capable of producing X-rays

An X-ray tube is a vacuum tube that converts electrical input power into X-rays.

$A powder X-ray diffractometer in motion$

X-ray crystallography

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$A powder X-ray diffractometer in motion$

Drawing of square (Figure A, above) and hexagonal (Figure B, below) packing from Kepler's work, Strena seu de Nive Sexangula.

As shown by X-ray crystallography, the hexagonal symmetry of snowflakes results from the tetrahedral arrangement of hydrogen bonds about each water molecule. The water molecules are arranged similarly to the silicon atoms in the tridymite polymorph of SiO2. The resulting crystal structure has hexagonal symmetry when viewed along a principal axis.

X-ray crystallography shows the arrangement of water molecules in ice, revealing the hydrogen bonds (1) that hold the solid together. Few other methods can determine the structure of matter with such precision (resolution).

$The incoming beam (coming from upper left) causes each scatterer to re-radiate a small portion of its intensity as a spherical wave. If scatterers are arranged symmetrically with a separation d, these spherical waves will be in sync (add constructively) only in directions where their path-length difference 2d sin θ equals an integer multiple of the wavelength λ. In that case, part of the incoming beam is deflected by an angle 2θ, producing a reflection spot in the diffraction pattern.$

Although diamonds (top left) and graphite (top right) are identical in chemical composition—being both pure carbon—X-ray crystallography revealed the arrangement of their atoms (bottom) accounts for their different properties. In diamond, the carbon atoms are arranged tetrahedrally and held together by single covalent bonds, making it strong in all directions. By contrast, graphite is composed of stacked sheets. Within the sheet, the bonding is covalent and has hexagonal symmetry, but there are no covalent bonds between the sheets, making graphite easy to cleave into flakes.

$First X-ray diffraction view of Martian soil – CheMin analysis reveals feldspar, pyroxenes, olivine and more (Curiosity rover at "Rocknest", October 17, 2012).$

The three-dimensional structure of penicillin, solved by Dorothy Crowfoot Hodgkin in 1945. The green, red, yellow and blue spheres represent atoms of carbon, oxygen, sulfur and nitrogen, respectively. The white spheres represent hydrogen, which were determined mathematically rather than by the X-ray analysis.

Ribbon diagram of the structure of myoglobin, showing alpha helices. Such proteins are long, linear molecules with thousands of atoms; yet the relative position of each atom has been determined with sub-atomic resolution by X-ray crystallography. Since it is difficult to visualize all the atoms at once, the ribbon shows the rough path of the protein's backbone from its N-terminus to its C-terminus.

Workflow for solving the structure of a molecule by X-ray crystallography.

A protein crystal seen under a microscope. Crystals used in X-ray crystallography may be smaller than a millimeter across.

Three methods of preparing crystals, A: Hanging drop. B: Sitting drop. C: Microdialysis

$An X-ray diffraction pattern of a crystallized enzyme. The pattern of spots (reflections) and the relative strength of each spot (intensities) can be used to determine the structure of the enzyme.$

Structure of a protein alpha helix, with stick-figures for the covalent bonding within electron density for the crystal structure at ultra-high-resolution (0.91 Å). The density contours are in gray, the helix backbone in white, sidechains in cyan, O atoms in red, N atoms in blue, and hydrogen bonds as green dotted lines.

3D depiction of electron density (blue) of a ligand (orange) bound to a binding site in a protein (yellow). The electron density is obtained from experimental data, and the ligand is modeled into this electron density.

X-ray crystallography is the experimental science determining the atomic and molecular structure of a crystal, in which the crystalline structure causes a beam of incident X-rays to diffract into many specific directions.

CT scan

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Medical imaging technique used to obtain detailed internal images of the body.

Drawing of CT fan beam and patient in a CT imaging system

Computed tomography of human brain, from base of the skull to top. Taken with intravenous contrast medium.

Bronchial wall thickness (T) and diameter of the bronchus (D)

Example of a CTPA, demonstrating a saddle embolus (dark horizontal line) occluding the pulmonary arteries (bright white triangle)

Types of presentations of CT scans:
- Average intensity projection
- Maximum intensity projection
- Thin slice (median plane)
- Volume rendering by high and low threshold for radiodensity

Typical screen layout for diagnostic software, showing one volume rendering (VR) and multiplanar view of three thin slices in the axial (upper right), sagittal (lower left), and coronal planes (lower right)

3D human skull from computed tomography data

Left image is a sinogram which is a graphic representation of the raw data obtained from a CT scan. At right is an image sample derived from the raw data.

The multiple X-ray measurements taken from different angles are then processed on a computer using tomographic reconstruction algorithms to produce tomographic (cross-sectional) images (virtual "slices") of a body.