title: Development of a training phantom for compression breast elastography-comparison of various elastography systems and numerical simulations.
abstract: The elastic properties of tissue are related to tissue composition and pathological changes. It has been observed that many pathological processes increase the elastic modulus of soft tissue compared to normal. Ultrasound compression elastography is a method of characterization of elastic properties that has been the focus of many research efforts in the last two decades. In medical radiology, compression elastography is provided as an additional tool with ultrasound B-mode in the existing scanners, and the combined features of elastography and echography act as a promising diagnostic method in breast cancer detection. However, the full capability of the ultrasound elastography technique together with B-mode has not been utilized by novice radiologists due to the nonavailability of suitable, appropriately designed tissue-mimicking phantoms. Since different commercially available ultrasound elastographic scanners follow their own unique protocols, training novice radiologists is becoming cumbersome. The main focus of this work is to develop a tissue-like agar-based phantom, which mimics breast tissue with common abnormal lesions like fibroadenoma and invasive ductal carcinoma in a clinically perceived way and compares the sonographic and elastographic appearances using different commercially available systems. In addition, the developed phantoms are simulated using the finite-element method, and ideal strain images are generated. Strain images from experiment and simulation are compared based on image contrast parameters, namely contrast transfer efficiency (CTE) and observed strain, and they are in good agreement. The strain image contrast of malignant inclusions is significantly improved compared to benign inclusions, and the trend of CTE is similar for all elastographic scanners under investigation.
authors.affiliation: Biomedical Engineering Group , Department of Applied Mechanics, IIT Madras, Chennai 600 036, India.
authors.forename: Kavitha
authors.initials: K
authors.lastname: Manickam
authors.affiliation: Biomedical Engineering Group , Department of Applied Mechanics, IIT Madras, Chennai 600 036, India.
authors.forename: Machireddy Ramasubba
authors.initials: MR
authors.lastname: Reddy
authors.affiliation: Mediscan Systems , Chennai 600 004, India.
authors.forename: Suresh
authors.initials: S
authors.lastname: Seshadri
authors.affiliation: Apollo Speciality Hospitals , Chennai 600 035, India.
authors.forename: Bagyam
authors.initials: B
authors.lastname: Raghavan
keywords: Itoh score; breast imaging-reporting and data system; finite-element simulations; stiffness imaging; tissue mimicking phantoms; ultrasound elastography