Premium
Accelerated statistical reconstruction for C‐arm cone‐beam CT using Nesterov's method
Author(s) -
Wang Adam S.,
Stayman J. Webster,
Otake Yoshito,
Vogt Sebastian,
Kleinszig Gerhard,
Siewerdsen Jeffrey H.
Publication year - 2015
Publication title -
medical physics
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.473
H-Index - 180
eISSN - 2473-4209
pISSN - 0094-2405
DOI - 10.1118/1.4914378
Subject(s) - iterative reconstruction , imaging phantom , cone beam computed tomography , image quality , computer vision , computer science , convergence (economics) , artificial intelligence , mathematics , algorithm , nuclear medicine , image (mathematics) , medicine , computed tomography , radiology , economic growth , economics
Purpose: To accelerate model‐based iterative reconstruction (IR) methods for C‐arm cone‐beam CT (CBCT), thereby combining the benefits of improved image quality and/or reduced radiation dose with reconstruction times on the order of minutes rather than hours. Methods: The ordered‐subsets, separable quadratic surrogates (OS‐SQS) algorithm for solving the penalized‐likelihood (PL) objective was modified to include Nesterov's method, which utilizes “momentum” from image updates of previous iterations to better inform the current iteration and provide significantly faster convergence. Reconstruction performance of an anthropomorphic head phantom was assessed on a benchtop CBCT system, followed by CBCT on a mobile C‐arm, which provided typical levels of incomplete data, including lateral truncation. Additionally, a cadaveric torso that presented realistic soft‐tissue and bony anatomy was imaged on the C‐arm, and different projectors were assessed for reconstruction speed. Results: Nesterov's method provided equivalent image quality to OS‐SQS while reducing the reconstruction time by an order of magnitude (10.0 ×) by reducing the number of iterations required for convergence. The faster projectors were shown to produce similar levels of convergence as more accurate projectors and reduced the reconstruction time by another 5.3 ×. Despite the slower convergence of IR with truncated C‐arm CBCT, comparison of PL reconstruction methods implemented on graphics processing units showed that reconstruction time was reduced from 106 min for the conventional OS‐SQS method to as little as 2.0 min with Nesterov's method for a volumetric reconstruction of the head. In body imaging, reconstruction of the larger cadaveric torso was reduced from 159 min down to 3.3 min with Nesterov's method. Conclusions: The acceleration achieved through Nesterov's method combined with ordered subsets reduced IR times down to a few minutes. This improved compatibility with clinical workflow better enables broader adoption of IR in CBCT‐guided procedures, with corresponding benefits in overcoming conventional limits of image quality at lower dose.