title: Tracked regularized ultrasound elastography for targeting breast radiotherapy.
abstract: Tracked ultrasound elastography can be used for guidance in partial breast radiotherapy by visualizing the hard scar tissue around the lumpectomy cavity. For clinical success, the elastography method needs to be robust to the sources of decorrelation between ultrasound images, specifically fluid motions inside the cavity, change of the appearance of speckles caused by compression or physiologic motions, and out-of-plane motion of the probe. In this paper, we present a novel elastography technique that is based on analytic minimization of a regularized cost function. The cost function incorporates similarity of RF data intensity and displacement continuity, making the method robust to small decorrelations present throughout the image. We also exploit techniques from robust statistics to make the method resistant to large decorrelations caused by sources such as fluid motion. The analytic displacement estimation works in real-time. Moreover, the tracked data, used for targeting the radiotherapy, is exploited for discarding frames with excessive out-of-plane motion. Simulation, phantom and patient results are presented.
authors.affiliation: Johns Hopkins University, Baltimore, MD, USA.
authors.forename: Hassan
authors.initials: H
authors.lastname: Rivaz
authors.forename: Pezhman
authors.initials: P
authors.lastname: Foroughi
authors.forename: Ioana
authors.initials: I
authors.lastname: Fleming
authors.forename: Richard
authors.initials: R
authors.lastname: Zellars
authors.forename: Emad
authors.initials: E
authors.lastname: Boctor
authors.forename: Gregory
authors.initials: G
authors.lastname: Hager
mesh_terms: D000465:Algorithms; D001185:Artificial Intelligence; D054459:Elasticity Imaging Techniques / Q000379:methods*; D005260:Female; D006801:Humans; D007089:Image Enhancement / Q000379:methods; D007090:Image Interpretation, Computer-Assisted / Q000379:methods*; D010363:Pattern Recognition, Automated / Q000379:methods*; D019047:Phantoms, Imaging; D011881:Radiotherapy, Computer-Assisted / Q000379:methods*; D020266:Radiotherapy, Conformal / Q000379:methods*; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D016217:Ultrasonography, Mammary / Q000379:methods*