title: Dual-mode registration of dynamic contrast-enhanced ultrasound combining tissue and contrast sequences.
abstract: This study proposes a new method for automatic, iterative image registration in the context of dynamic contrast-enhanced ultrasound (DCE-US) imaging. By constructing a cost function of image registration using a combination of the tissue and contrast-microbubble responses, this new method, referred to as dual-mode registration, performs alignment based on both tissue and vascular structures. Data from five focal liver lesions (FLLs) were used for the evaluation. Automatic registration based on the dual-mode registration technique and tissue-mode registration obtained using the linear response image sequence alone were compared to manual alignment of the sequence by an expert. Comparison of the maximum distance between the transformations applied by the automatic registration techniques and those from expert manual registration reference showed that the dual-mode registration provided better precision than the tissue-mode registration for all cases. The reduction of maximum distance ranged from 0.25 to 9.3mm. Dual-mode registration is also significantly better than tissue-mode registration for the five sequences with p-values lower than 0.03. The improved sequence alignment is also demonstrated visually by comparison of images from the sequences and the video playbacks of the motion-corrected sequences. This new registration technique better maintains a selected region of interest (ROI) within a fixed position of the image plane throughout the DCE-US sequence. This should reduce motion-related variability of the echo-power estimations and, thus, contribute to more robust perfusion quantification with DCE-US.
authors: UPMC Univ Paris 06, UMR 7623, LIP, F-75005, Paris, France; CNRS, UMR 7623, LIP, F-75006, Paris, France. Electronic address: nizar.bouhlel@u-paris10.fr.
authors: Nizar
authors: N
authors: Bouhlel
authors: UPMC Univ Paris 06, UMR 7623, LIP, F-75005, Paris, France; CNRS, UMR 7623, LIP, F-75006, Paris, France. Electronic address: alain.coron@upmc.fr.
authors: Alain
authors: A
authors: Coron
authors: UPMC Univ Paris 06, UMR 7623, LIP, F-75005, Paris, France; CNRS, UMR 7623, LIP, F-75006, Paris, France. Electronic address: guillaume.barrois@upmc.fr.
authors: Guillaume
authors: G
authors: Barrois
authors: AP-HP, Hôpital Pitié-Salpêtrière, Service de radiologie, F-75013, Paris, France. Electronic address: olivier.lucidarme@psl.aphp.fr.
authors: Olivier
authors: O
authors: Lucidarme
authors: UPMC Univ Paris 06, UMR 7623, LIP, F-75005, Paris, France; CNRS, UMR 7623, LIP, F-75006, Paris, France. Electronic address: lori.bridal@upmc.fr.
authors: S Lori
authors: SL
authors: Bridal
mesh_terms: D015179:Colorectal Neoplasms / Q000473:pathology*; D003287:Contrast Media; D006801:Humans; D007090:Image Interpretation, Computer-Assisted; D008113:Liver Neoplasms / Q000000981:diagnostic imaging* / Q000556:secondary*; D008962:Models, Theoretical; D010743:Phospholipids; D012984:Software; D013459:Sulfur Hexafluoride; D014159:Transducers; D014463:Ultrasonography
chemical_list: D003287:Contrast Media; D010743:Phospholipids; C420843:contrast agent BR1; D013459:Sulfur Hexafluoride
keywords: Contrast image; Dynamic contrast-enhanced ultrasound; Maximum distance; Motion compensation; Registration