collimation

collimation /col·li·ma·tion/ (kol?i-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.