Jing Shan, Presenter: Nothing to Disclose

Andrew Tucker, Abstract Co-Author: Nothing to Disclose

Yueh Z. Lee MD, PhD, Abstract Co-Author: Research Grant, Carestream Health, Inc

Michael D Heath, Abstract Co-Author: Employee, Carestream Health, Inc

Xiaohui Wang PhD, Abstract Co-Author: Employee, Carestream Health, Inc

David Foos MS, Abstract Co-Author: Employee, Carestream Health, Inc

Jianping Lu, Abstract Co-Author: Research Grant, Carestream Health, Inc

Otto Zhou PhD, Abstract Co-Author: Board of Directors, XinRay Systems Inc Research Grant, Carestream Health, Inc

The purpose of this work is to investigate the feasibility of constructing a stationary chest tomosynthesis system using a stationary CNT source array, and to evaluate the relationship between source geometry configurations and the tomosynthesis image quality.

A bench-top chest tomosynthesis system using a CNT source array (XinRay Systems, NC) and a flat panel detector (Carestream Health Inc. NY) was built. The source array contains 75 focal spots operating at 80kVp and 5mA anode current. The tube output and entrance dose were measured. Projection images were reconstructed using commercial software (Realtime Tomography, Pa). System in-plane resolution and in-depth resolution were measured using a 100um cross-wire phantom at different source configurations including linear-source geometry with different angular coverage and a square-source geometry. In addition, anthropomorphic chest phantom images were acquired and reconstructed for image quality assessment.

All the CNT x-ray sources in the source array can be reliably and consistently operated at 80kVp with 5mA anode current with 150ms pulse width. An entrance dose at detector of 6mR was generated at 0.75mAs. The system MTF remains essentially the same at ~3.4cyles/mm while the in-depth resolution improves significantly from 9.3mm to 5.1mm, as the angular coverage increases from 12° to 34° in the linear source geometry. For square source geometry (at angular coverage of 10°) the system MTF and in-depth resolution is found to be comparable with that of a linear geometry at the same angular coverage. Chest phantom images were reconstructed to slices spaced 4mm. The tomosynthesis slices clearly show airways and pulmonary vascular structures in the lung of the physical phantom in both source geometries.

The experimental results demonstrate the feasibility of stationary chest tomosynthesis. This can lead to improved system design, potentially faster imaging speed, and reduced patient motion blur. The CNT source array is capable of delivering sufficient x-ray flux and dose required for chest tomosynthesis. The square source geometry shows comparable in-plane and in-depth resolutions as linear geometry.

Stationary tomosynthesis system can improve image quality and reduce image acquisition time, which can improve the workflow and benefit the detection of small lung nodules and other chest pathology.

Shan, J, Tucker, A, Lee, Y, Heath, M, Wang, X, Foos, D, Lu, J, Zhou, O, Stationary Chest Tomosynthesis System Using Distributed CNT X-ray Source Array.  Radiological Society of North America 2013 Scientific Assembly and Annual Meeting, December 1 - December 6, 2013 ,Chicago IL. http://archive.rsna.org/2013/13016309.html