Editing Radiography (section)

==Equipment==
[[File:Coude fp.PNG|thumb|A plain radiograph of the [[elbow]]]]
[[File:AP lumbar xray.jpg|thumb|upright|AP radiograph of the [[lumbar spine]]]]
[[File:Hand Xray (48630648876).jpg|thumb|upright|A hand prepared to be X-rayed]]

===Sources===
{{Further|X-ray generator}}

In medicine and dentistry, [[projectional radiography]] and [[CT scan|computed tomography images]] generally use X-rays created by [[X-ray generator]]s, which generate X-rays from [[X-ray tube]]s.  The resultant images from the radiograph (X-ray generator/machine) or CT scanner are correctly referred to as "radiograms"/"roentgenograms" and "tomograms" respectively.

A number of other sources of [[X-ray]] [[photon]]s are possible, and may be used in industrial radiography or research; these include [[betatron]]s, [[Linear particle accelerator|linear accelerators]] (linacs), and [[synchrotron]]s. For [[gamma ray]]s, [[radioactive]] sources such as [[Iridium-192|<sup>192</sup>Ir]], [[Cobalt-60|<sup>60</sup>Co]], or [[Caesium-137|<sup>137</sup>Cs]] are used.

===Grid===
An [[anti-scatter grid]] may be placed between the patient and the detector to reduce the quantity of scattered x-rays that reach the detector. This improves the contrast resolution of the image, but also increases radiation exposure for the patient.<ref>{{cite book |last=Bushberg |first=Jerrold T | name-list-style = vanc |title=The Essential Physics of Medical Imaging |date=2002 |publisher=Lippincott Williams & Wilkins |location=Philadelphia |isbn=9780683301182 |page=210 |edition=2nd |url=https://books.google.com/books?id=VZvqqaQ5DvoC&pg=PA210 }}</ref>

===Detectors===
{{Main|X-ray detector}}

Detectors can be divided into two major categories: imaging detectors (such as [[photographic plate]]s and X-ray film ([[photographic film]]), now mostly replaced by various [[digitizing]] devices like [[image plate]]s or [[flat panel detector]]s) and dose measurement devices (such as [[ionization chamber]]s, [[Geiger counter]]s, and [[dosimeter]]s used to measure the local [[exposure (radiation)|radiation exposure]], [[absorbed dose|dose]], and/or dose rate, for example, for verifying that [[radiation protection]] equipment and procedures are effective on an ongoing basis).<ref>{{cite journal | vauthors = Ranger NT | title = Radiation detectors in nuclear medicine | journal = Radiographics | volume = 19 | issue = 2 | pages = 481–502 | date = 1999 | pmid = 10194791 | doi = 10.1148/radiographics.19.2.g99mr30481 | doi-access =  }}</ref><ref>{{cite journal | vauthors = DeWerd LA, Wagner LK | title = Characteristics of radiation detectors for diagnostic radiology | journal = Applied Radiation and Isotopes | volume = 50 | issue = 1 | pages = 125–36 | date = January 1999 | pmid = 10028632 | doi = 10.1016/S0969-8043(98)00044-X | bibcode = 1999AppRI..50..125D }}</ref><ref>{{cite book | last1 = Anwar | first1 = Kamal | name-list-style = vanc | title = Particle Physics | pages = 1–78 | date = 2013 | publisher = Springer-Verlag | location = Berlin | isbn = 978-3-642-38660-2 | chapter = Nuclear Radiation Detectors | doi = 10.1007/978-3-642-38661-9_1 | series = Graduate Texts in Physics }}</ref>

=== Side markers ===
A radiopaque anatomical side marker is added to each image. For example, if the patient has their right hand x-rayed, the radiographer includes a radiopaque "R" marker within the field of the x-ray beam as an indicator of which hand has been imaged. If a physical marker is not included, the radiographer may add the correct side marker later as part of digital post-processing.<ref>{{cite journal | vauthors = Barry K, Kumar S, Linke R, Dawes E | title = A clinical audit of anatomical side marker use in a paediatric medical imaging department | journal = Journal of Medical Radiation Sciences | volume = 63 | issue = 3 | pages = 148–54 | date = September 2016 | pmid = 27648278 | pmc = 5016612 | doi = 10.1002/jmrs.176 }}</ref>

===Image intensifiers and array detectors===
{{Main|X-ray image intensifier}}
As an alternative to X-ray detectors, [[X-ray image intensifier|image intensifiers]] are analog devices that readily convert the acquired X-ray image into one visible on a video screen. This device is made of a vacuum tube with a wide input surface coated on the inside with [[caesium iodide]] (CsI). When hit by X-rays, phosphor material causes the [[photocathode]] adjacent to it to emit electrons. These electrons are then focused using electron lenses inside the intensifier to an output screen coated with phosphorescent materials. The image from the output can then be recorded via a camera and displayed.<ref>{{cite book|last1=Hendee|first1=William R.|last2=Ritenour|first2=E. Russell| name-list-style = vanc |title=Medical Imaging Physics|date=2002|publisher=John Wiley & Sons|location=Hoboken, NJ|isbn=9780471461135|edition=4th|chapter-url=https://books.google.com/books?id=55lh1B82SLsC&pg=PA236|chapter=Fluoroscopy}}</ref>

Digital devices known as array detectors are becoming more common in fluoroscopy. These devices are made of discrete pixelated detectors known as [[thin-film transistor]]s (TFT) which can either work ''indirectly'' by using photo detectors that detect light emitted from a scintillator material such as CsI, or ''directly'' by capturing the electrons produced when the X-rays hit the detector. Direct detectors do not tend to experience the blurring or spreading effect caused by phosphorescent scintillators or by film screens since the detectors are activated directly by X-ray photons.<ref>{{cite journal | vauthors = Seibert JA | title = Flat-panel detectors: how much better are they? | journal = Pediatric Radiology | volume = 36 Suppl 2 | issue = S2 | pages = 173–81 | date = September 2006 | pmid = 16862412 | pmc = 2663651 | doi = 10.1007/s00247-006-0208-0 }}</ref>