Carolina Amador has contributed significantly to research characterizing the viscoelastic properties of soft tissues using various acoustic methods such as Shearwave Dispersion Ultrasound Vibrometry (SDUV) and Acoustic Radiation Force Induced Creep (ARFIC). She has validated these methods on tissue mimicking phantoms and applied them to study properties of organs like the kidney and liver. Her work has also focused on developing techniques to characterize anisotropic and transverse isotropic materials, as well as factors that influence tissue properties such as blood flow.

1. Contributions to Science
Shearwave Dispersion Ultrasound Vibrometry (SDUV) method is a method capable of
measuring viscoelastic material properties. Significant amount of my work have been related to
fundamental studies to quantify viscoelastic material properties of soft tissues and tissue
mimicking phantoms. I contributed to the validation of SDUV with experiments in gelatin
phantoms. Additionally, we showed factors that influence tissue mimicking phantoms
mechanical properties. I have also studied other tissue-like materials, like micellar fluids,
viscoelastic properties with acoustic radiation force shear wave method and conventional
rheology method.
1. Amador, Carolina, Urban, Matthew W., Chen, Shigao, Chen, Qingshan,Kai-Nan, An,
Greenleaf, James F - Shear elastic modulus estimation from indentation and SDUV on
gelatin phantoms. IEEE Transactions on Biomedical Engineering, 58(6): 1706-1714,
June 2011.
2. Loyd, Andre M., Amador, Carolina, An, Kai-Nan - The Effects of Time and Moisture on
Ultrasound Phantom Physical and Mechanical properties: A Pilot Study. Revista
Ingenieria Biomedica 2014, 8(15):27-35.
3. Amador, C., Otilio, Bruno L., Kinnick, Randall R., Urban, Matthew W. – Ultrasonic
method to characterize shear wave propagation in micellar fluids. Journal of the
acoustical society of America, 2013 (E-print).
I have contributed to research targeted towards characterizing the mechanical properties of the
kidney. We have used Magnetic Resonance Elastography to study renal tissue elasticity. I have
also contributed to renal tissue viscoelastic characterization using Shearwave Dispersion
Ultrasound Vibrometry (SDUV) method. I have also performed worked related to study factors
that influence renal tissue viscoelasticity, for instance, tissue anisotropy and blood flow.
Recently, I have contributed to research related to the use of shockwave therapy to improve
kidney microcirculation.
1. Warner. Lizette, Yin, Meng, Glaser, Kevin J., Woollard, John A., Amador, Carolina,
Korsmo, Michael J., Ehman, Richard L., Lerman, Lilach O. - Noninvasive in vivo
assessment of renal tissue elasticity using MR Elastography: Preliminary findings.
Investigative Radiology, 46(8): 509-514, August 2011.
2. Amador, Carolina, Urban, Matthew W., Chen, Shigao, Greenleaf, James F. -
Shearwave Dispersion Ultrasound Vibrometry (SDUV) on swine kidney. IEEE
Transactions on Ultrasonics, Ferroelectrics and Frequency Control, December 2011.
3. Amador, Carolina, Urban, Matthew W., Kinnick, Randall, Chen, Shigao, Greenleaf,
James F. - In vivo swine kidney viscoelasticity during acute gradual decrease in renal
blood flow: pilot study. Revista Ingenieria Biomedica EIA. Volumen 7, Numero 13,
Enero-Junio 2013, pp. 68-78.
4. Zhang, X., Krier, J.D., Amador, C., Greenleaf, J. F., Ebrahimi, B., Textor, S.C., Lerman,
A., Lerman, L.O. - Low-energy extracorporeal shockwave improves the microcirculation
in the swine ischemic kidney. Journal of the American Society of Nephrology, 2016 (E-
print).

2. I developed a method to measure tissue viscoelasticity using acoustic radiation force. The
method was termed Acoustic Radiation Force Induced Creep (ARFIC) because we induced
viscoelastic creep response with acoustic radiation force. We have used ARFIC method in
combination with SDUC method to measured complex viscoelastic shear modulus of tissue
mimicking phantoms and ex vivo porcine kidney. I have also contributed to the development of a
viscoelastic imaging method with a compression device.
1. Amador, Carolina, Urban, Matthew W, Chen, Shigao, Greenleaf, James F. – Loss
tangent and complex modulus estimated by acoustic radiation force creep and shear
wave dispersion. Physics in Medicine and Biology, Feb. 2012.
2. Nabavizadeh, Alireza; Kinnick, Randall R; Bayat, Mahdi; Amador, Carolina; Urban,
Matthew W.; Alizad, Azra; Fatemi, Mostafa - Automated Compression Device for
Viscoelasticity Imaging – IEEE Transactions on Biomedical Engineering, 2016 (E-print)
I have contributed to developing methods for making viscoelastic properties measurements in
anisotropic materials. We have created imaging phantoms that exhibit the properties of a
transverse isotropic material, similar in nature to skeletal muscle. We have made measurements
of anisotropy in ex vivo skeletal muscle and kidney. I have also contributed to study arterial and
plaque mechanical properties with shear wave elastography.
1. Aristizabal, Sara, Amador, Carolina, Qiang, Bo, Kinnick, Randall, Nenadic, Ivan,
Greenleaf, James, Urban, Matthew - Shear wave vibrometry evaluation in transverse
isotropic tissue mimicking phantoms and skeletal muscle. Physics in Medicine and
Biology, Nov, 2014.
2. Urban, Matthew W., Lopera, Manuela, Aristizabal, Sara, Amador, Carolina, Nenadic,
Ivan, Kinnick, Randall, Weston, Alexander, Qiang, Bo, Zhang, Xiaoming, Greenleaf,
James - Characterization of Transverse Isotropy in Compressed Tissue-Mimicking
Phantoms. IEEE Transactions on Ultrasonics, Ferroelectrics and Frequency Control,
June 2015.
3. Widman, E., Maksuti, E., Amador, C., Urban, M., Caidahl, K., Larsson, M. - Shear Wave
Elastography Quantifies Stiffness in ex vivo Porcine Artery with Simulated Plaque - IEEE
Transactions on Medical Imaging, 2016 (E-print).
A major limitation to ultrasound based shear wave elasticity imaging is poor ultrasound imaging
quality that affects shear wave motion quality. I have contributed to fundamental studies to
improve acoustic radiation force based shear wave elasticity imaging. One study is related to
the effects of phase aberration to acoustic radiation force shear wave generation. In another
study we improved shear wave detection by using ultrasound harmonic imaging.
1. Amador, Carolina, Aristizabal, Sara, Greenleaf, James F., Urban, Matthew W. – Phase
Aberration and Attenuation Effects on Acoustic Radiation Force-Based Shear Wave
Generation. IEEE Transactions on Ultrasonics, Ferroelectrics and Frequency Control,
January 2016.
2. Amador, C., Song, Pengfei, Meixner, Duane, Chen, Shigao, Urban, Matthew –
Improvement of shear wave motion detection using harmonic imaging in healthy human
liver. Ultrasound in medicine and biology, January 2016.