Photoacoustic computed tomography for joint reconstruction of initial pressure and sound speed in vivo using a feature coupling method

Based on the energy conversion of light into sound, photoacoustic computed tomography (PACT) is an emerging biomedical imaging modality and has unique applications in a range of biomedical fields. In PACT, image formation relies on a process called acoustic inversion from received photoacoustic signals. While most PACT systems perform this inversion with a basic assumption that biological tissues are acoustically homogeneous, the community gradually realizes that the intrinsic acoustic heterogeneity of tissues could pose distortions and artifacts to finally formed images. This paper surveys the most recent research progress on acoustic heterogeneity correction in PACT. Four major strategies are reviewed in detail, including half-time or partial-time reconstruction, autofocus reconstruction by optimizing sound speed maps, joint reconstruction of optical absorption and sound speed maps, and ultrasound computed tomography (USCT) enhanced reconstruction. The correction of acoustic heterogeneity helps improve the imaging performance of PACT.

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Joint reconstruction of initial pressure distribution and acoustic skull parameters in transcranial photoacoustic computed tomography (Conference Presentation)

Photons Plus Ultrasound: Imaging and Sensing 2018 ◽

10.1117/12.2290890 ◽

2018 ◽

Cited By ~ 2

Author(s):

Joemini Poudel ◽

Thomas P. Matthews ◽

Mark A. Anastasio ◽

Lihong V. Wang

Keyword(s):

Computed Tomography ◽

Pressure Distribution ◽

Initial Pressure ◽

Joint Reconstruction

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Joint Reconstruction of Absorbed Optical Energy Density and Sound Speed Distributions in Photoacoustic Computed Tomography: A Numerical Investigation

IEEE Transactions on Computational Imaging ◽

10.1109/tci.2016.2523427 ◽

2016 ◽

Vol 2 (2) ◽

pp. 136-149 ◽

Cited By ~ 18

Author(s):

Chao Huang ◽

Kun Wang ◽

Robert W. Schoonover ◽

Lihong V. Wang ◽

Mark A. Anastasio

Keyword(s):

Computed Tomography ◽

Energy Density ◽

Numerical Investigation ◽

Sound Speed ◽

Optical Energy ◽

Joint Reconstruction

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Tantalum Oxide Nanoparticles as Versatile Contrast Agents for X-ray Computed Tomography

10.26434/chemrxiv.11845572.v1 ◽

2020 ◽

Author(s):

Shatadru Chakravarty ◽

Jeremy Hix ◽

Kaitlyn Wieweora ◽

Maximilian Volk ◽

Elizabeth Kenyon ◽

...

Keyword(s):

Computed Tomography ◽

Contrast Agents ◽

Mesoporous Silica Nanoparticles ◽

Sol Gel ◽

Tantalum Oxide ◽

High Signal ◽

Drug Delivery Vehicles ◽

X Ray Computed

Here we describe the synthesis, characterization and in vitro and in vivo performance of a series of tantalum oxide (TaOx) based nanoparticles (NPs) for computed tomography (CT). Five distinct versions of 9-12 nm diameter silane coated TaOx nanocrystals (NCs) were fabricated by a sol-gel method with varying degrees of hydrophilicity and with or without fluorescence, with the highest reported Ta content to date (78%). Highly hydrophilic NCs were left bare and were evaluated in vivo in mice for micro-CT of full body vasculature, where following intravenous injection, TaOx NCs demonstrate high CT contrast, circulation in blood for ~ 3 h, and eventual accumulation in RES organs; and following injection locally in the mammary gland, where the full ductal tree structure can be clearly delineated. Partially hydrophilic NCs were encapsulated within mesoporous silica nanoparticles (MSNPs; TaOx@MSNPs) and hydrophobic NCs were encapsulated within poly(lactic-co-glycolic acid) (PLGA; TaOx@PLGA) NPs, serving as potential CT-imagable drug delivery vehicles. Bolus intramuscular injections of TaOx@PLGA NPs and TaOx@MSNPs to mimic the accumulation of NPs at a tumor site produce high signal enhancement in mice. In vitro studies on bare NCs and formuated NPs demonstrate high cytocompatibility and low dissolution of TaOx. This work solidifies that TaOx-based NPs are versatile contrast agents for CT.

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Trends in Nanotechnology for in vivo Cancer Diagnosis: Products and Patents

Current Pharmaceutical Design ◽

10.2174/1381612826666200219094853 ◽

2020 ◽

Vol 26 (18) ◽

pp. 2167-2181

Author(s):

Tatielle do Nascimento ◽

Melanie Tavares ◽

Mariana S.S.B. Monteiro ◽

Ralph Santos-Oliveira ◽

Adriane R. Todeschini ◽

...

Keyword(s):

Computed Tomography ◽

Quantum Dots ◽

Magnetic Resonance ◽

Metal Nanoparticles ◽

Cancer Diagnosis ◽

Imaging Techniques ◽

Tumor Detection ◽

Abnormal Growth ◽

Pharmaceutical Nanotechnology

Background: Cancer is a set of diseases formed by abnormal growth of cells leading to the formation of the tumor. The diagnosis can be made through symptoms’ evaluation or imaging tests, however, the techniques are limited and the tumor detection may be late. Thus, pharmaceutical nanotechnology has emerged to optimize the cancer diagnosis through nanostructured contrast agent’s development. Objective: This review aims to identify commercialized nanomedicines and patents for cancer diagnosis. Methods: The databases used for scientific articles research were Pubmed, Science Direct, Scielo and Lilacs. Research on companies’ websites and articles for the recognition of commercial nanomedicines was performed. The Derwent tool was applied for patent research. Results: This article aimed to research on nanosystems based on nanoparticles, dendrimers, liposomes, composites and quantum dots, associated to imaging techniques. Commercialized products based on metal and composite nanoparticles, associated with magnetic resonance and computed tomography, have been observed. The research conducted through Derwent tool displayed a small number of patents using nanotechnology for cancer diagnosis. Among these patents, the most significant number was related to the use of systems based on metal nanoparticles, composites and quantum dots. Conclusion: Although few systems are found in the market and patented, nanotechnology appears as a promising field for the development of new nanosystems in order to optimize and accelerate the cancer diagnosis.

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