Akira Hagiwara MS, Presenter: Employee, General Electric Company

Masayuki Kudo MD, Abstract Co-Author: Employee, General Electric Company

Takamichi Murakami MD, PhD, Abstract Co-Author: Nothing to Disclose

Noriyuki Tomiyama MD, PhD, Abstract Co-Author: Nothing to Disclose

Yukinobu Yagyu MD, Abstract Co-Author: Nothing to Disclose

Makoto Gohno MSc, Abstract Co-Author: Employee, General Electric Company

Koji Yamada RT, Abstract Co-Author: Nothing to Disclose

Kazuhiko Satoh MBBS, Abstract Co-Author: Nothing to Disclose

Junko Sekiguchi, Abstract Co-Author: Employee, General Electric Company

Jaynne Leverentz RT, Abstract Co-Author: Employee, General Electric Company

Paul Licato MS, Abstract Co-Author: Employee, General Electric Company

et al, Abstract Co-Author: Nothing to Disclose

et al, Abstract Co-Author: Nothing to Disclose

We developed a dynamic pitch helical 3D reconstruction algorithm, and advanced table control (ATC) to support advancements in wide coverage temporal imaging. In this study, we evaluate the algorithm and image quality with phantom and clinical studies for Continuous Helical Shuttle Scan (CHSS).

CHSS allows multiple scans around whole organ with continuous movement of table back-and-forth over a wide coverage with included acceleration / deceleration regions. To realize this new application, we propose to utilize the dynamic table speed and dynamic pitch helical scan with a GE Healthcare LightSpeed VCT utilizing research software. ATC is designed to collect the accurate position data for each view/time. It can realize the dynamic pitch reconstruction. An optimized dynamic pitch 3D reconstruction is developed to image during the dynamic table speeds.

The collected position data can realize the accurate reconstruction geometry as a distance from recon plane to X-ray source-detector for each view. The optimized reconstruction can realize the continuous IQ (image quality: resolution, noise, artifact) and realize the equivalent IQ to conventional constant table speed helical. The variation of helical pitch is from 0.0 to 1.375. And the clinical studies were done for CHSS with the coverage from 120mm to 220mm, time interval from 1.4sec to 2.2sec. CHSS is useful to observe 4D CT angiography and perfusion of whole organ with wider coverage and less time interval. This dynamic pitch 3D reconstruction technique could also be used to enhance and reduce the dose of TRO.

The VCT system with dynamic Pitch Helical and Advanced Table Control can realize good image quality during accelerated/decelerated table movement. The feasibility of the dynamic pitch helical reconstruction algorithm to realize outstanding image quality for CHSS was demonstrated.

A wide 40mm detector and these advanced algorithms and table capabilities realize new CHSS adaptive acquisition techniques. It enables expanded coverage CT applications with a 1-2sec time interval.

Hagiwara, A, Kudo, M, Murakami, T, Tomiyama, N, Yagyu, Y, Gohno, M, Yamada, K, Satoh, K, Sekiguchi, J, Leverentz, J, Licato, P, et al, , et al, , Development of Dynamic Pitch Helical Reconstruction Algorithm for Continuous Helical Shuttle Scan of 64ch MDCT with Advanced Table Control.  Radiological Society of North America 2007 Scientific Assembly and Annual Meeting, November 25 - November 30, 2007 ,Chicago IL. http://archive.rsna.org/2007/5004117.html