title: Attenuation Correction and Normalisation for Quantification of Contrast Enhancement in Ultrasound Images of Carotid Arteries.
abstract: An automated attenuation correction and normalisation algorithm was developed to improve the quantification of contrast enhancement in ultrasound images of carotid arteries. The algorithm first corrects attenuation artefact and normalises intensity within the contrast agent-filled lumen and then extends the correction and normalisation to regions beyond the lumen. The algorithm was first validated on phantoms consisting of contrast agent-filled vessels embedded in tissue-mimicking materials of known attenuation. It was subsequently applied to in vivo contrast-enhanced ultrasound (CEUS) images of human carotid arteries. Both in vitro and in vivo results indicated significant reduction in the shadowing artefact and improved homogeneity within the carotid lumens after the correction. The error in quantification of microbubble contrast enhancement caused by attenuation on phantoms was reduced from 55% to 5% on average. In conclusion, the proposed method exhibited great potential in reducing attenuation artefact and improving quantification in contrast-enhanced ultrasound of carotid arteries.
authors.affiliation: Department of Bioengineering, Imperial College London, London, UK.
authors.forename: Wing Keung
authors.initials: WK
authors.lastname: Cheung
authors.affiliation: Head and Neck Unit, Royal Marsden Hospital, London, UK.
authors.forename: Dorothy M
authors.initials: DM
authors.lastname: Gujral
authors.affiliation: Biomedical Research Unit, NHLI, Imperial College, London, UK.
authors.forename: Benoy N
authors.initials: BN
authors.lastname: Shah
authors.affiliation: Biomedical Research Unit, NHLI, Imperial College, London, UK.
authors.forename: Navtej S
authors.initials: NS
authors.lastname: Chahal
authors.affiliation: Biomedical Research Unit, NHLI, Imperial College, London, UK.
authors.forename: Sanjeev
authors.initials: S
authors.lastname: Bhattacharyya
authors.affiliation: Imaging Department, Imperial College London, London, UK.
authors.forename: David O
authors.initials: DO
authors.lastname: Cosgrove
authors.affiliation: Division of Imaging Sciences, King's College London, London, UK.
authors.forename: Robert J
authors.initials: RJ
authors.lastname: Eckersley
authors.affiliation: Head and Neck Unit, Royal Marsden Hospital, London, UK.
authors.forename: Kevin J
authors.initials: KJ
authors.lastname: Harrington
authors.affiliation: Biomedical Research Unit, NHLI, Imperial College, London, UK.
authors.forename: Roxy
authors.initials: R
authors.lastname: Senior
authors.affiliation: Head and Neck Unit, Royal Marsden Hospital, London, UK.
authors.forename: Christopher M
authors.initials: CM
authors.lastname: Nutting
authors.affiliation: Department of Bioengineering, Imperial College London, London, UK. Electronic address: mengxing.tang@imperial.ac.uk.
authors.forename: Meng-Xing
authors.initials: MX
authors.lastname: Tang
mesh_terms: D000465:Algorithms; D016477:Artifacts; D002339:Carotid Arteries / Q000000981:diagnostic imaging*; D006801:Humans; D007089:Image Enhancement / Q000379:methods*; D007090:Image Interpretation, Computer-Assisted / Q000379:methods*; D019047:Phantoms, Imaging; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D014463:Ultrasonography / Q000295:instrumentation / Q000379:methods*
keywords: Adventitial vasa vasorum; Attenuation correction; Carotid artery; Contrast-enhanced ultrasound; Perfusion quantification; Shadowing