Development of Prospective Gating in Stationary Digital Chest Tomosynthesis Using a Carbon Nanotube X-ray Source Array Public Deposited

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  • March 22, 2019
  • Hartman, Allison
    • Affiliation: College of Arts and Sciences, Department of Physics and Astronomy
  • Purpose: To quantify the benefit of prospectively gated stationary digital chest tomosynthesis (Gs-DCT) using a carbon nanotube (CNT) x-ray source array in a free breathing porcine study. Methods: The Gs-DCT x-ray system consists of a linear x-ray array tube (80kVp, 0.125mAs per projection for 29 projections over a 12 angular span) and a flat panel detector (5 fps). Imaging was performed on an anesthetized, free-breathing 13.5kg pig. A respiratory trace was acquired through a transducer belt around the thorax. Each gated projection image was acquired at the temporal coincidence of the detector integration time and the peak inhalation of the pig. The projection images were reconstructed using iterative reconstruction with a 2mm slice thickness using iterative reconstruction. Image blur was assessed as the reproduction of the diaphragm in the reconstructed images. Respiratory phase timing quality was assessed through cross-correlation analysis. Results: Animal respiration rate was 24.3+/-3.5bpm. The scan time for the gated scan was 86.9 +/- 2.9s compared to the un-gated scanning time 6.3 .6s. An entrance dose of 0.4mSv was used. The blur in the reproduction of the diaphragm in the reconstructed images for gated study was 1.8 0.5mm where in the un-gated case the diaphragm was 2.60.6 mm. The average cross correlation coefficient between of the respiratory trace at the time of the x-ray pulse was .91.02 for the gated scan and .11+/- .01 for the un-gated scan. Conclusions: Prospective gated imaging significantly reduced the motion blur, substantially improving the image quality of the tomosynthesis images. The CNT based x-ray sources enable precise x-ray pulse generation on demand. If enabled clinically, the Gs-DCT system could potentially obtain 3D image stacks in patients that are unable to hold their breaths, such as the pediatric or intubated patient population. Prospectively gated human studies are planned.
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  • In Copyright
  • Karwowski, Hugon
  • Branca, Rosa Tamara
  • Lalush, David
  • Zhou, Otto
  • Lu, Jianping
  • Lee, Yueh
  • Doctor of Philosophy
Degree granting institution
  • University of North Carolina at Chapel Hill
Graduation year
  • 2017

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