Hayadan > A technology developed at the Technion improves the quality of photographs in the depth of the tissue

A technology developed at the Technion improves the quality of photographs in the depth of the tissue

The new method was demonstrated on neurons in the brain

In the table of pictures: pictures of neurons that were taken in the system. On the left: a normal photograph of a neuron deep in the tissue. In the middle: the dramatic improvement provided by the new technology. On the right: a real image of the neuron taken without scattering tissue.

Researchers at the Viterbi Faculty of Electrical and Computer Engineering present in the journal Nature Communications. A new approach in wavefront design. This approach has extensive and very significant applications, especially inNon-invasive biological imaging of tissue depth, and the new technology is demonstrated in an article about neurons (nerve cells).

Wavefront design is a promising approach for deep tissue imaging. Until now, this approach has been made possible by means of a "third party" - fluorescent dots that were inserted into the sample manually, and the tissue was indirectly mapped by their images. This process has many disadvantages, and from the beginning it was clear that direct imaging of the tissue was a better way. However, direct imaging involves various difficulties, and one of them is the fact that the radiation emitted from tissues is a weak radiation and therefore its measurement is prone to errors, especially when it comes to imaging the depth of the tissue.

The new technology presented by the Technion researchers overcomes these limitations and presents the possibility of direct imaging of the tissue through illumination of a neuron labeled with the fluorescent protein EGFP. This protein emits, in response to light on it, light of a different color. This technology is based on Double repair of the wavefronts - repair of the wavefront sent to the tissue and repair of the wavefront returning from it. With the help of mathematical calculations that weight the ratio between signal and noise, the researchers achieved a high resolution of the neurons deep in the tissue.

Doctoral student Dror Izik, who conducted the research under the guidance of Prof. Anat Levin, explains that "previous demonstrations of wavefront design corrected quite minor distortions and were only effective for very limited tissue depths. Our research demonstrated the technology for the first time in performing imaging to the depth of the tissue and correcting very large distortions, which without our correction would have caused the resulting images to be 'noise images' that do not contain any visual information."

The new technology did provide high-quality images of the neurons and the axons coming out of them, even when the neurons are covered by a layer of tissue. The researchers clarify that technology demonstrated on neurons is also relevant to many other tissues.

In the big diagram: a scheme of the new technology. Top left: The incoming wave (in blue) comes from the left and undergoes foreground correction in the Illumination SLM. After that, it enters the tissue, hits the neuron, and from there comes the return wave (in green) that undergoes foreground correction in SLM imaging. Below on the left you can see the resulting image before correction (right) and after (left). In the right part you can see above the incoming light (in blue) and the outgoing light (in green) before the repair (in the two upper pictures) and after it (in the lower pictures).

The research was supported by the European Research Commission (ERC), the Israel-USA Binational Science Foundation (BSF) and the National Science Foundation (ISF).

Prof. Anat Levin She joined the Technion faculty in 2016, after a doctorate at the Hebrew University, a post-doctorate at MIT and about seven years at the Weizmann Institute of Science. She deals in optics, image processing and computer vision and has won many awards, including the Michael Bruno Award, the Bluntic Award and the Krill Award.

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