Computer simulation of magnetic resonance angiography imaging: model description and validation

• Published in: PloS one Vol. 9; no. 4; p. e93689
• Main Authors: Klepaczko, Artur, Szczypiński, Piotr, Dwojakowski, Grzegorz, Strzelecki, Michał, Materka, Andrzej
• Format: Journal Article
• Language: English
• Published: United States Public Library of Science 01.04.2014; Public Library of Science (PLoS)
• Subjects: Algorithms; Analysis; Angiography; Biology and Life Sciences; Blood flow; Blood vessels; Computer and Information Sciences; Computer Simulation; Data acquisition; Design; Digital imaging; Electronics; Engineering and Technology; Flow profiles; Flow simulation; Fluid flow; Fourier transforms; Geometry; Image processing; Image segmentation; Imaging, Three-Dimensional; Magnetic resonance; Magnetic Resonance Angiography; Magnetic resonance imaging; Magnetization; Medical imaging; Medicine and Health Sciences; Models, Anatomic; NMR; Noise; Nuclear magnetic resonance; Physical Sciences; Physics; Quantitative analysis; Regional Blood Flow; Resonance; Segmentation; Signal processing; Simulation; Three dimensional flow
• ISSN: 1932-6203; 1932-6203
• DOI: 10.1371/journal.pone.0093689

With the development of medical imaging modalities and image processing algorithms, there arises a need for methods of their comprehensive quantitative evaluation. In particular, this concerns the algorithms for vessel tracking and segmentation in magnetic resonance angiography images. The problem can be approached by using synthetic images, where true geometry of vessels is known. This paper presents a framework for computer modeling of MRA imaging and the results of its validation. A new model incorporates blood flow simulation within MR signal computation kernel. The proposed solution is unique, especially with respect to the interface between flow and image formation processes. Furthermore it utilizes the concept of particle tracing. The particles reflect the flow of fluid they are immersed in and they are assigned magnetization vectors with temporal evolution controlled by MR physics. Such an approach ensures flexibility as the designed simulator is able to reconstruct flow profiles of any type. The proposed model is validated in a series of experiments with physical and digital flow phantoms. The synthesized 3D images contain various features (including artifacts) characteristic for the time-of-flight protocol and exhibit remarkable correlation with the data acquired in a real MR scanner. The obtained results support the primary goal of the conducted research, i.e. establishing a reference technique for a quantified validation of MR angiography image processing algorithms.