scholarly journals Ultrasonic Ring Array-Based Transient Triplet Differential Photoacoustic Imaging for Strong Background Removal

2021 ◽  
Vol 8 ◽  
Author(s):  
Guan Wang ◽  
Bo Wang ◽  
Tong Ye ◽  
Congcong Wang ◽  
Lili Guo ◽  
...  
Keyword(s):  
Molecular Imaging ◽  
Contrast Agent ◽  
Contrast Agents ◽  
Spatial Resolution ◽  
Photoacoustic Imaging ◽  
High Specificity ◽  
Background Signal ◽  
Background Removal ◽  
Differential Imaging

Photoacoustic imaging (PAI) is a fast evolving imaging technology enabling in vivo imaging with high specificity and spatial resolution. However, due to strong background signals from various intrinsic chromospheres such as melanin, photoacoustic imaging of targeting objects labeled by contrast agents remain a challenge. The transient triplet differential (TTD) method has shown a significant potential for background-free photoacoustic imaging. Here, we develop a photoacoustic system using an ultrasonic semicircular ring array for transient triplet differential imaging. Pt(II) Octaethylporphine (PtOEP) and black ink are used as the contrast agent and the phantom of melanoma, respectively. Using the TTD method, we could remove the strong background signal from black ink. The ratio between contrast agent signal and background signal is increased to about 10 times the previous one. Our finding demonstrates the potential of the TTD method on molecular imaging for strong background removal.

scholarly journals Study on Establishing Reference Safe Concentrations of MRI Contrast Agents for Optimized Images: Paramagnetic Gd-DTPA-BMEA and Superparamagnetic Ferucarbotran

2021 ◽  
Vol 11 (3) ◽  
pp. 1165
Author(s):  
Wen-Tien Hsiao ◽  
Yi-Hong Chou ◽  
Jhong-Wei Tu ◽  
Ai-Yih Wang ◽  
Lu-Han Lai
Keyword(s):  
Contrast Agent ◽  
Contrast Agents ◽  
Mri Contrast Agents ◽  
Mri Contrast Agent ◽  
In Vitro Experiments ◽  
Mri Contrast ◽  
In Vivo Experiments ◽  
Contrast Agent Injection

The purpose of this study is to establish the minimal injection doses of magnetic resonance imaging (MRI) contrast agents that can achieve optimized images while improving the safety of injectable MRI drugs. Gadolinium-diethylenetriamine penta-acetic acid (Gd-DTPA) and ferucarbotran, commonly used in clinical practice, were selected and evaluated with in vitro and in vivo experiments. MRI was acquired using T1-weighted (T1W) and T2-weighted (T2W) sequences, and the results were quantitatively analyzed. For in vitro experiments, results showed that T1W and T2W images were optimal when Gd-DTPA-bisamide (2-oxoethyl) (Gd-DTPA-BMEA) and ferucarbotran were diluted to a volume percentage of 0.6% and 0.05%; all comparisons were significant differences in grayscale statistics using one-way analysis of variance (ANOVA). For in vivo experiments, the contrast agent with optimal concentration percentages determined from in vitro experiments were injected into mice with an injection volume of 100 μL, and the images of brain, heart, liver, and mesentery before and after injection were compared. The statistical results showed that the p values of both T1W and T2W were less than 0.001, which were statistically significant. Under safety considerations for MRI contrast agent injection, optimized MRI images could still be obtained after reducing the injection concentration, which can provide a reference for the safety concentrations of MRI contrast agent injection in the future.

Antimonene Nanoflakes as a Photoacoustic Imaging Contrast Agent for Tumor in vivo Imaging

2020 ◽  
Vol 47 (2) ◽  
pp. 0207033
Author(s):  
于静文 Yu Jingwen ◽  
王秀翃 Wang Xiuhong ◽  
冯金超 Feng Jinchao ◽  
张娜 Zhang Na ◽  
王璞 Wang Pu
Keyword(s):  
Contrast Agent ◽  
In Vivo Imaging ◽  
Photoacoustic Imaging ◽  
Imaging Contrast Agent

Cardiovascular Molecular Imaging

2015 ◽  
Author(s):  
Alan R. Morrison ◽  
Joseph C. Wu ◽  
Mehran M. Sadeghi
Keyword(s):  
Molecular Imaging ◽  
Photoacoustic Imaging ◽  
Nuclear Imaging ◽  
Biological Information ◽  
Novel Approach ◽  
Novel Therapeutic Strategies ◽  
Pathologic Processes ◽  
Cardiovascular Molecular Imaging ◽  
Accurate Quantification

Cardiovascular molecular imaging is a relatively young but rapidly expanding discipline that consists of a biologically-targeted approach to the assessment of physiologic and pathologic processes in vivo. This novel approach to imaging involves the integration of multiple disciplines such as cell and molecular biology, chemistry, and imaging sciences. The ultimate goal is quantitative assessment of cardiovascular processes at the cellular and molecular level, moving beyond traditional diagnostic information, in order to guide individually tailored therapy. In fact, it is likely that specific approaches to molecular imaging will be developed in tandem with the development of novel therapeutic strategies. Recent advances in probe development and imaging systems have contributed to evolution of molecular imaging toward clinical translational. These include technological progress in traditional imaging platforms; along with the emergence of newer imaging modalities such as photoacoustic imaging. In addition, hybrid imaging (e.g. nuclear imaging with CT or MRI) has the potential for improved spatial localization, and more accurate quantification by coupling anatomic and biological information. In addition to potential clinical applications that address existing diagnostic gaps in cardiovascular medicine, molecular imaging allows for unique approaches to studying pathophysiology. This chapter is intended to provide an overview of the state of the art in cardiovascular molecular imaging, highlighting how it may improve the management of major cardiovascular diseases.

scholarly journals Photoacoustic reporter genes for noninvasive molecular imaging and theranostics

2020 ◽  
Vol 13 (03) ◽  
pp. 2030005
Author(s):  
Zhao Lei ◽  
Yun Zeng ◽  
Xiaofen Zhang ◽  
Xiaoyong Wang ◽  
Gang Liu
Keyword(s):  
Molecular Imaging ◽  
Fluorescent Proteins ◽  
Photoacoustic Imaging ◽  
High Sensitivity ◽  
Reporter Genes ◽  
Biological Processes ◽  
Deep Tissue ◽  
Potential Applications ◽  
Improved Performance

Noninvasive molecular imaging makes the observation and comprehensive understanding of complex biological processes possible. Photoacoustic imaging (PAI) is a fast evolving hybrid imaging technology enabling in vivo imaging with high sensitivity and spatial resolution in deep tissue. Among the various probes developed for PAI, genetically encoded reporters attracted increasing attention of researchers, which provide improved performance by acquiring images of a PAI reporter gene’s expression driven by disease-specific enhancers/promoters. Here, we present a brief overview of recent studies about the existing photoacoustic reporter genes (RGs) for noninvasive molecular imaging, such as the pigment enzyme reporters, fluorescent proteins and chromoproteins, photoswitchable proteins, including their properties and potential applications in theranostics. Furthermore, the challenges that PAI RGs face when applied to the clinical studies are also examined.

Styryl BODIPY Derivatives as Contrast Agents for In Vivo Photoacoustic Imaging

2017 ◽  
Author(s):  
Maryam Hatamimoslehabadi ◽  
Stephanie Bellinger ◽  
Jonathan Rochford ◽  
Chandra S Yelleswarapu
Keyword(s):  
Contrast Agents ◽  
Photoacoustic Imaging

PEGylated Gd(OH)3 nanorods as metabolizable contrast agents for computed tomography imaging

2015 ◽  
Vol 39 (11) ◽  
pp. 8999-9005 ◽  
Author(s):  
Yingda Du ◽  
Ming Xing ◽  
Zhiman Li ◽  
Wei Guo
Keyword(s):  
Computed Tomography ◽  
Contrast Agent ◽  
Contrast Agents ◽  
Computed Tomography Imaging ◽  
Hydrothermal Route ◽  
Tomography Imaging

PEGylated Gd(OH)3 nanorods have been efficiently prepared via a facile and green hydrothermal route and used as a metabolizable computed tomography contrast agent for in vivo imaging.

scholarly journals Molecular imaging perspectives

2005 ◽  
Vol 2 (3) ◽  
pp. 133-144 ◽  
Author(s):  
Paul J Cassidy ◽  
George K Radda
Keyword(s):  
Molecular Imaging ◽  
Contrast Agents ◽  
Physical Science ◽  
Life Science ◽  
Interdisciplinary Collaboration ◽  
Nuclear Imaging ◽  
Imaging Modalities ◽  
Molecular Events ◽  
Biological Target

Molecular imaging is an emerging technology at the life science/physical science interface which is set to revolutionize our understanding and treatment of disease. The tools of molecular imaging are the imaging modalities and their corresponding contrast agents. These facilitate interaction with a biological target at a molecular level in a number of ways. The diverse nature of molecular imaging requires knowledge from both the life and physical sciences for its successful development and implementation. The aim of this review is to introduce the subject of molecular imaging from both life science and physical science perspectives. However, we will restrict our coverage to the prominent in vivo molecular imaging modalities of magnetic resonance imaging, optical imaging and nuclear imaging. The physical basis of these imaging modalities, the use of contrast agents and the imaging parameters of sensitivity, temporal resolution and spatial resolution are described. Then, the specificity of contrast agents for targeting and sensing molecular events, and some applications of molecular imaging in biology and medicine are given. Finally, the diverse nature of molecular imaging and its reliance on interdisciplinary collaboration is discussed.

Targeted tumor MRI with gadobutrol-loaded anti-HER2 immunoliposomes

2016 ◽  
Vol 58 (5) ◽  
pp. 573-580 ◽  
Author(s):  
Weicui Chen ◽  
Bo Liu ◽  
Jun Chen ◽  
Guoqing Liu ◽  
Xian Liu
Keyword(s):  
Contrast Agent ◽  
Contrast Agents ◽  
Signal To Noise Ratio ◽  
Cellular Level ◽  
Cancer Tissue ◽  
Post Injection ◽  
Specific Tumor ◽  
Noise Ratio ◽  
Targeted Contrast Agent

Background Immunoliposomes have been used to deliver MR contrast agents to cancer tissue by targeting tumor associated antigens, thus enabling the visualization of biological processes at the cellular level. Purpose To develop and evaluate the feasibility of specific HER2 targeted liposomal MR contrast agent. Material and Methods Gd-loaded anti-HER2 immunolipomes (Gd-ILs) and non-targeted PEGylated liposomes (Gd-NTLs) were prepared and characterized. Tumor bearing animals were randomized into three groups: Gd- ILs, Gd- NTLs and gadobutrol. Animals were imaged prior and 5, 15, 60, 120 and 180 min after i.v. injection of different contrast agents. The signal intensity enhancement percentage, signal- to- noise ratio and contrast- to –noise ratio was used to qualify tumor enhancement of different groups. After imaging, tumors were excised for histological examination. Results In vivo dynamic MR images, the specific targeted contrast agent bound to tumor tissue and result in a gradual and persisting enhancement for at least 3 hours in mice bearing tumor xenografts, reaching a maximum of 87.7% enhancement after 120 min post-injection. Gd-ILs demonstrated superior tumor enhancement over control non target contrast agent and gadobutrol in HER2 overexpressing tumors at 60, 120 and 180 min post- injection. The SNR and CNR of Gd-ILs in the tumors were significantly greater than that of Gd-NTLs at 60, 120, 180 min post- injection. Conclusion The results indicate the feasibility of Gd-ILs providing prolonged circulation, specific tumor enhancement and cancer cell recognition as targeted contrast agent.

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