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PubMed · 3983409

CT collimator damage: detection by testing scan beam and laser-light alignment.

M J McCullough
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Abstract

A test for CT scanner laser-light alignment is described. Ready-pack film is taped around a cylindrical phantom, and laser-light position relative to x-ray beam track is indicated by an arrangement of pin pricks through the film jacket. Performance of this test after x-ray tube replacement showed a band of stray radiation running parallel to the scan beam. The errant beam was caused by a failure to interlock the prepatient collimator and scatter shield correctly.

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M J McCullough. 1985. CT collimator damage: detection by testing scan beam and laser-light alignment.. https://doi.org/10.1148/radiology.155.2.3983409

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