title: Denoising and artefact reduction in dynamic flat detector CT perfusion imaging using high speed acquisition: first experimental and clinical results.
abstract: Flat detector CT perfusion (FD-CTP) is a novel technique using C-arm angiography systems for interventional dynamic tissue perfusion measurement with high potential benefits for catheter-guided treatment of stroke. However, FD-CTP is challenging since C-arms rotate slower than conventional CT systems. Furthermore, noise and artefacts affect the measurement of contrast agent flow in tissue. Recent robotic C-arms are able to use high speed protocols (HSP), which allow sampling of the contrast agent flow with improved temporal resolution. However, low angular sampling of projection images leads to streak artefacts, which are translated to the perfusion maps. We recently introduced the FDK-JBF denoising technique based on Feldkamp (FDK) reconstruction followed by joint bilateral filtering (JBF). As this edge-preserving noise reduction preserves streak artefacts, an empirical streak reduction (SR) technique is presented in this work. The SR method exploits spatial and temporal information in the form of total variation and time-curve analysis to detect and remove streaks. The novel approach is evaluated in a numerical brain phantom and a patient study. An improved noise and artefact reduction compared to existing post-processing methods and faster computation speed compared to an algebraic reconstruction method are achieved.
authors: Pattern Recognition Lab, Department of Computer Science, Friedrich-Alexander-Universität Erlangen-Nürnberg, Martensstr. 3, 91058 Erlangen, Germany. Department of Neuroradiology, Universitätsklinikum Erlangen, Schwabachanlage 6, 91054 Erlangen, Germany.
authors: Michael T
authors: MT
authors: Manhart
authors: André
authors: A
authors: Aichert
authors: Tobias
authors: T
authors: Struffert
authors: Yu
authors: Y
authors: Deuerling-Zheng
authors: Markus
authors: M
authors: Kowarschik
authors: Andreas K
authors: AK
authors: Maier
authors: Joachim
authors: J
authors: Hornegger
authors: Arnd
authors: A
authors: Doerfler
mesh_terms: D000368:Aged; D000465:Algorithms; D016477:Artifacts; D001921:Brain / Q000098:blood supply / Q000000981:diagnostic imaging; D005260:Female; D006801:Humans; D008297:Male; D009068:Movement; D055420:Perfusion Imaging / Q000379:methods*; D019047:Phantoms, Imaging; D011856:Radiographic Image Enhancement / Q000379:methods*; D012399:Rotation; D059629:Signal-To-Noise Ratio; D020521:Stroke / Q000000981:diagnostic imaging / Q000503:physiopathology; D013997:Time Factors; D014057:Tomography, X-Ray Computed / Q000379:methods*