Abstract:
:The presence of motion artifacts is a typical problem in thoracic imaging. However, synchronizing the respiratory cycle with computed tomography (CT) image acquisition can reduce these artifacts. We currently employ a method of in vivo respiratory-gated micro-CT imaging for small laboratory animals (mice). This procedure involves the use of a ventilator that controls the respiratory cycle of the animal and provides a digital output signal that is used to trigger data acquisition. After inspection of the default respiratory trigger timing, we hypothesized that image quality could be improved by moving the data-acquisition window to a portion of the cycle with less respiratory motion. For this reason, we developed a simple delay circuit to adjust the timing of the ventilator signal that initiates micro-CT data acquisition. This delay circuit decreases motion artifacts and substantially improves image quality.
journal_name
Phys Med Bioljournal_title
Physics in medicine and biologyauthors
Walters EB,Panda K,Bankson JA,Brown E,Cody DDdoi
10.1088/0031-9155/49/17/023subject
Has Abstractpub_date
2004-09-07 00:00:00pages
4163-72issue
17eissn
0031-9155issn
1361-6560journal_volume
49pub_type
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