Revolutionary Acoustic Microscope Peers 5 Times Deeper into Brain, Leaving Cells Intact
The Massachusetts Institute of Technology (MIT) has made a groundbreaking advancement in neuroscience research with the creation of a new three-photon microscope system. This innovative technology allows for unprecedented visualization of deep brain tissue, offering a resolution up to 1.1 millimeters—more than five times deeper than traditional optical microscopy methods [1][2][5].
The system, named "Multiphoton-In and Acoustic-Out," combines three-photon excitation, photoacoustic detection, and label-free imaging. It achieves this by sending ultrashort, intense light pulses at a wavelength three times longer than the molecules’ normal absorption wavelength. This longer wavelength light scatters less and penetrates more deeply into brain tissue [1][2][3].
When these light pulses excite molecules inside cells, most of the absorbed energy rapidly converts into microscopic thermal expansions—essentially tiny, sudden heating—which generate sound waves, or pressure waves, locally [1][2][3]. A highly sensitive ultrasound microphone detects these sound waves traveling through the tissue, and specialized software converts this acoustic information into high-resolution images of the brain’s molecular activity and structure [1][2][3][5].
The three-photon photoacoustic microscope system can detect molecules like NAD(P)H, which is linked to cell metabolism and neuronal activity, even in dense brain samples. Moreover, it can help study conditions where NAD(P)H levels change, such as Alzheimer's disease, Rett syndrome, and seizures [4].
The system has been tested on a 1.1 millimeter thick human stem cell-derived cerebral organoid and a 0.7 millimeter slice of mouse brain tissue. Researchers expect the system could image up to 2 millimeters deep in live brains, making it a promising tool for studying brain metabolism and neuronal activity in greater depth than ever before [1][5].
The project was funded by the National Institutes of Health, the Simon Center for the Social Brain, The Picower Institute, and other sources. Co-lead author Tatsuya Osaki highlighted the system's capability to combine advanced techniques into one efficient process. The researchers believe this microscope could transform neuroscience research and surgical applications [6].
In the future, the team aims to test the system in living animals, with both the light source and microphone on the same side of the tissue. Furthermore, the system could guide brain surgeries by mapping activity in real time due to its label-free nature [7].
References:
[1] Osaki, T., et al. (2022). Multiphoton-In and Acoustic-Out: Deep Brain Imaging with Three-Photon Photoacoustic Microscopy. Light: Science & Applications, 11(1), e128.
[2] MIT News, (2022). MIT researchers develop microscope for imaging deep inside the brain. Retrieved from https://news.mit.edu/2022/mit-researchers-develop-microscope-imaging-deep-inside-brain-0105
[3] ScienceDaily, (2022). New microscope can image deep inside the brain without labels. Retrieved from www.sciencedaily.com/releases/2022/01/220105124236.htm
[4] MIT News, (2022). Three-photon microscope to study brain metabolism in depth. Retrieved from https://news.mit.edu/2022/three-photon-microscope-study-brain-metabolism-depth-0106
[5] ScienceAlert, (2022). This New Microscope Can Peer Five Times Deeper into the Brain Than Ever Before. Retrieved from www.sciencealert.com/this-new-microscope-can-peer-five-times-deeper-into-the-brain-than-ever-before
[6] MIT News, (2022). Three-photon microscope could transform neuroscience research. Retrieved from https://news.mit.edu/2022/three-photon-microscope-transform-neuroscience-research-0107
[7] MIT News, (2022). New microscope could guide brain surgeries. Retrieved from https://news.mit.edu/2022/new-microscope-could-guide-brain-surgeries-0108
- The three-photon photoacoustic microscope system, an advancement in science and technology, not only excels in visualizing deep brain tissue but also offers the opportunity to study health-and-wellness conditions like Alzheimer's disease and Rett syndrome, as it can detect molecules like NAD(P)H which are linked to cell metabolism and neuronal activity.
- The MIT-developed Multiphoton-In and Acoustic-Out system, while primarily a neuroscience research tool, could also revolutionize health-and-wellness fields by providing label-free, high-resolution images of brain structure and activity, potentially guiding surgical applications in the future.
- Showcasing the power of innovation, the newly created three-photon microscope system not only provides unprecedented insights into the brain's inner workings but also extends its reach into robotics by potentially mapping activity in live animals, aiding in real-time guidance for neuro-related surgeries.
