This New Microscope Can Look Through Your Skull Safely

Being able to see inside our bodies without cutting through barriers like flesh and bone is a very complicated thing to do. Bone, for one, is a thick and inconsistent structure, so it scatters light unpredictably. That makes it hard to decipher what’s going on behind them. But no matter what you’re trying to see through, the deeper you wish to see, the more the light scatters and obscures the biological structures within.

However, the ability to see-thru just got a step closer to reality. A team of scientists from the Institute for Basic Science (IBS) in Seoul, South Korea, has developed a way to create a clear image from scattered infrared laser light, even after passing through a thick layer of bone.

Research professor YOON Seokchan and graduate student LEE Hojun, a couple of the physicists who conducted the study, said:

Our microscope allows us to investigate fine internal structures deep within living tissues that cannot be resolved by any other means.

The breakthrough in deep-tissue optical imaging involves a novel optical microscope that can image through an intact mouse skull. It can acquire a microscopic map of neural networks in the brain tissues non-invasively without losing spatial resolution. The system combines imaging techniques with computational adaptive optics power to correct optical distortion.

Conventional imaging microscopes only focus on the point of illumination. But the team’s novel reflection matrix microscope also records all the scattered photons at their positions. Then, an algorithm corrects the scattered photons for optical aberrations. The system corrects ten times the number of abnormalities as a standard system.

It has an additional advantage that it can be directly linked with a conventional two-photon microscope widely used in the life science field to remove aberrations in its images.

Vice director CHOI Wonshik said:

Reflection matrix microscope is the next-generation technology that goes beyond the limitations of conventional optical microscopes. This will allow us to widen our understanding of the light propagation through scattering media and expand the scope of applications that an optical microscope can explore.

The team demonstrated their reflection matrix microscope’s capabilities by taking two-photon fluorescence images of a neuron’s dendritic spine behind the mouse skull. Typically, such a feat wouldn’t be possible without removing the brain tissue from the head entirely.

This was the first high-resolution imaging of neural networks through an intact mouse skull, meaning it’s now possible to investigate the mouse brain in its most native states. It’s a highly significant achievement. Visualizing biological structures in their natural living context could reveal more about their functions and roles. It can also allow for easier detection of medical problems.

Yoon and Lee said:

By correcting the wavefront distortion, we can focus light energy on the desired location inside the living tissue. This will greatly aid us in early disease diagnosis and expedite neuroscience research.

The team’s next aim is to increase the microscopes imaging speed and minimize its form factor. The overall goal is to develop a label-free reflective matrix microscope with high imaging depth that can be used in clinics. Perhaps, their aberration correction algorithm could also be linked to other imaging techniques and equipment, allowing them to resolve more in-depth images.