High-Resolution Ultrasound-Switchable Fluorescence Imaging in Centimeter-Deep Tissue Phantoms with High Signal-To-Noise Ratio and High Sensitivity via Novel Contrast Agents.
For many years, investigators have sought after high-resolution fluorescence imaging in centimeter-deep tissue because many interesting in vivo phenomena-such as the presence of immune system cells, tumor angiogenesis, and metastasis-may be located deep in tissue. Previously, we developed a new imaging technique to achieve high spatial resolution in sub-centimeter deep tissue phantoms named continuous-wave ultrasound-switchable fluorescence (CW-USF). The principle is to use a focused ultrasound wave to externally and locally switch on and off the fluorophore emission from a small volume (close to ultrasound focal volume). By making improvements in three aspects of this technique: excellent near-infrared USF contrast agents, a sensitive frequency-domain USF imaging system, and an effective signal processing algorithm, for the first time this study has achieved high spatial resolution (~ 900 μm) in 3-centimeter-deep tissue phantoms with high signal-to-noise ratio (SNR) and high sensitivity (3.4 picomoles of fluorophore in a volume of 68 nanoliters can be detected). We have achieved these results in both tissue-mimic phantoms and porcine muscle tissues. We have also demonstrated multi-color USF to image and distinguish two fluorophores with different wavelengths, which might be very useful for simultaneously imaging of multiple targets and observing their interactions in the future. This work has opened the door for future studies of high-resolution centimeter-deep tissue fluorescence imaging.
Ultrasound and Optical Imaging Laboratory, Department of Bioengineering, University of Texas at Arlington, Arlington, Texas, 76010, United States of America.|Joint Biomedical Engineering Program, University of Texas at Arlington and University of Texas Southwestern Medical Center at Dallas, Dallas, Texas, 75235, United States of America.
Bingbing
B
Cheng
Department of Chemistry, University of North Texas, 1155, Union Circle, #305070, Denton, Texas, 76203, United States of America.
Venugopal
V
Bandi
Ultrasound and Optical Imaging Laboratory, Department of Bioengineering, University of Texas at Arlington, Arlington, Texas, 76010, United States of America.|Joint Biomedical Engineering Program, University of Texas at Arlington and University of Texas Southwestern Medical Center at Dallas, Dallas, Texas, 75235, United States of America.
Ming-Yuan
MY
Wei
Ultrasound and Optical Imaging Laboratory, Department of Bioengineering, University of Texas at Arlington, Arlington, Texas, 76010, United States of America.|Joint Biomedical Engineering Program, University of Texas at Arlington and University of Texas Southwestern Medical Center at Dallas, Dallas, Texas, 75235, United States of America.
Yanbo
Y
Pei
Department of Chemistry, University of North Texas, 1155, Union Circle, #305070, Denton, Texas, 76203, United States of America.
Francis
F
D'Souza
Joint Biomedical Engineering Program, University of Texas at Arlington and University of Texas Southwestern Medical Center at Dallas, Dallas, Texas, 75235, United States of America.|Department of Bioengineering, University of Texas at Arlington, Arlington, Texas, 76010, United States of America.
Kytai T
KT
Nguyen
Joint Biomedical Engineering Program, University of Texas at Arlington and University of Texas Southwestern Medical Center at Dallas, Dallas, Texas, 75235, United States of America.|Department of Bioengineering, University of Texas at Arlington, Arlington, Texas, 76010, United States of America.
Yi
Y
Hong
Ultrasound and Optical Imaging Laboratory, Department of Bioengineering, University of Texas at Arlington, Arlington, Texas, 76010, United States of America.|Joint Biomedical Engineering Program, University of Texas at Arlington and University of Texas Southwestern Medical Center at Dallas, Dallas, Texas, 75235, United States of America.
Baohong
B
Yuan
D000465:Algorithms; D000818:Animals; D003287:Contrast Media / Q000737:chemistry*; D005453:Fluorescence; D005456:Fluorescent Dyes / Q000737:chemistry*; D009132:Muscles / Q000000981:diagnostic imaging; D019047:Phantoms, Imaging; D015203:Reproducibility of Results; D059629:Signal-To-Noise Ratio; D013552:Swine; D014463:Ultrasonography / Q000295:instrumentation / Q000379:methods*
D003287:Contrast Media; D005456:Fluorescent Dyes