Journal Article

Multispectral Opto-acoustic Tomography (MSOT) of the Brain and Glioblastoma Characterization

Claussen, Jing, Ntziachristos, Vasilis, Razansky, Daniel, Jetzfellner, Thomas, Morscher, Stefan, Driessen, Wouter H.P., Patel, Manishkumar, Taruttis, Adrian, Beziere, Nicolas, Bednar, Bohumil, Burton, Neal C.

2013

Overview

Brain research depends strongly on imaging for assessing function and disease in vivo. We examine herein multispectral opto-acoustic tomography (MSOT), a novel technology for high-resolution molecular imaging deep inside tissues. MSOT illuminates tissue with light pulses at multiple wavelengths and detects the acoustic waves generated by the thermoelastic expansion of the environment surrounding absorbing molecules. Using spectral unmixing analysis of the data collected, MSOT can then differentiate the spectral signatures of oxygenated and deoxygenated hemoglobin and of photo-absorbing agents and quantify their concentration. By being able to detect absorbing molecules up to centimeters deep in the tissue it represents an ideal modality for small animal brain imaging, simultaneously providing anatomical, hemodynamic, functional, and molecular information. In this work we examine the capacity of MSOT in cross-sectional brain imaging of mice. We find unprecedented optical imaging performance in cross-sectional visualization of anatomical and physiological parameters of the mouse brain. For example, the potential of MSOT to characterize ischemic brain areas was demonstrated through the use of a carbon dioxide challenge. In addition, indocyanine green (ICG) was injected intravenously, and the kinetics of uptake and clearance in the vasculature of the brain was visualized in real-time. We further found that multiparameter, multispectral imaging of the growth of U87 tumor cells injected into the brain could be visualized through the intact mouse head, for example through visualization of deoxygenated hemoglobin in the growing tumor. We also demonstrate how MSOT offers several compelling features for brain research and allows time-dependent detection and quantification of brain parameters that are not available using other imaging methods without invasive procedures. ► MSOT offers high resolution imaging of anatomy and physiology in cross sections. ► MSOT resolves oxy- and deoxy-genated hemoglobin and optical agents in real-time. ► Multiple molecules can be multiplexed for concurrent imaging. ► We expect that MSOT will enable new insights into brain function and disease.

• Publisher: Elsevier Inc,Elsevier,Elsevier Limited
• Subject: Acoustics / Animals / Biological and medical sciences / Brain / Brain Neoplasms - pathology / Brain research / Disease / Disease Models, Animal / Female / Fundamental and applied biological sciences. Psychology / Glioblastoma / Glioblastoma - pathology / Image Processing, Computer-Assisted / In vivo imaging / Lasers / Medical imaging / Medical research / Mice / Mice, Nude / Molecular Imaging - methods / Multispectral opto-acoustic tomography / Nanoparticles / Photoacoustic Techniques - methods / Tomography / Tomography - methods / Vertebrates: nervous system and sense organs