Printer Friendly
Dictionary, Encyclopedia and Thesaurus - The Free Dictionary
1,518,605,485 visitors served.
forum mailing list For webmasters
?
New: Language forums
Dictionary/
thesaurus
Medical
dictionary
Legal
dictionary
Financial
dictionary
Acronyms
 
Idioms
Encyclopedia
Wikipedia
encyclopedia
?

collimation

   Also found in: Dictionary/thesaurus, Wikipedia 0.07 sec.
collimation /col·li·ma·tion/ (kol″ĭ-ma´shun)
1. in microscopy, the process of making light rays parallel; the adjustment or aligning of optical axes.
2. in radiology, the elimination of the more divergent portion of an x-ray beam.
3. in nuclear medicine, the use of a perforated absorber to restrict the field of view of a detector and reduce scatter.

col·li·ma·tion (kl-mshn)
n.
1. The process of restricting and confining an x-ray beam to a given area.
2. In nuclear medicine, the process of restricting the detection of emitted radiations to a given area of interest.

collimation (kol´imā´shn),
n in radiology, collimation refers to the elimination of the peripheral (more divergent) portion of a useful radiographic beam by means of metal tubes, cones, or diaphragms interposed in the path of the beam. See also diaphragm.
collimation, rectangular,
n a method for minimizing a patient's exposure to unnecessary radiation during treatment by using a rectangular position-indicating device (PID) to reduce the size of the radiation beam.

collimation
in microscopy, the process of making light rays parallel; the adjustment of two or more optical axes with respect to each other. In radiology, the restriction of the beam size to the area under investigation. This reduces the scattered radiation reaching the x-ray film and the exposure of attendants.

collimation 
1. The making of a bundle of light rays parallel.
2. In radiography, limiting the size of the beam to the required region on the patient, thereby protecting the remainder of the patient from radiation.

collimation
Radiation physics The formal process in which a beam or field of radiation is reduced with a lead diaphragm, tube, or cone


How to thank TFD for its existence? Tell a friend about us, add a link to this page, add the site to iGoogle, or visit webmaster's page for free fun content.
?Page tools
Printer friendly
Cite / link
Email
Feedback
Add definition
? Mentioned in ? References in periodicals archive
 
Other problems have included improper collimation, no purging and incorrect zero diopter settings and infinity focus.
We performed thoracic high-resolution computed axial tomography (HRCT), using 7 mm helical technique after intravenous contrast administration followed by high-resolution imaging, using 1 mm collimation every 1 cm from lung apex to base (Figure 1B-D).
 
Medical browser? ? Full browser
 
 
Medical Dictionary
?

Disclaimer | Privacy policy | Feedback | Copyright © 2009 Farlex, Inc.
All content on this website, including dictionary, thesaurus, literature, geography, and other reference data is for informational purposes only. This information should not be considered complete, up to date, and is not intended to be used in place of a visit, consultation, or advice of a legal, medical, or any other professional. Terms of Use.