Accurate image reconstruction using real C-arm data from a Circle-plus-arc trajectory

作者：Hoppe Stefan; Hornegger Joachim; Dennerlein Frank^*; Lauritsch Guenter; Noo Frederic

来源：International Journal of Computer Assisted Radiology and Surgery, 2012, 7(1): 73-86.

DOI：10.1007/s11548-011-0607-z

• C-arm
• Cone-beam reconstruction
• Computed tomography

Objective Developing an efficient tool for accurate three-dimensional imaging from projections measured with C-arm systems. %26lt;br%26gt;Material and methods A circle-plus-arc trajectory, which is complete and thus amenable to accurate reconstruction, is used. This trajectory is particularly attractive as its implementation does not require moving the patient. For reconstruction, we use the %26quot;M-line method%26quot;, which allows processing the data in the efficient filtered backprojection mode. This method also offers the advantage of not requiring an ideal data acquisition geometry, i.e., the M-line algorithm can account for known deviations in the scanning geometry, which is important given that sizeable deviations are generally encountered in C-arm imaging. %26lt;br%26gt;Results A robust implementation scheme of the %26quot;M-line method%26quot; that applies straightforwardly to real C-arm data is presented. In particular, a numerically stable technique to compute the view-dependent derivative with respect to the source trajectory parameter is applied, and an efficient way to compute the pi-line backprojection intervals via a polygonal weighting mask is presented. Projection data of an anthropomorphic thorax phantom were acquired on a medical C-arm scanner and used to demonstrate the benefit of using a complete data acquisition geometry with an accurate reconstruction algorithm versus using a state-of-the-art implementation of the conventional Feldkamp algorithm with a circular short scan of cone-beam data. A significant image quality improvement based on visual assessment is shown in terms of cone-beam artifacts.

• 出版日期2012-1