Scientists at MIT have found a way to jack up the efficiency of X-ray scintillators by at least tenfold and potentially up to a hundred times.

Scintillators convert incoming radiation into visible light that shows a patient’s anatomy during an imaging exam. When certain nanoscale configurations, such as arrays of wave-like ridges, are made to the material surface, scintillators may improve quality and reduce dose exposure in diagnostic X-ray or CT scans, says MIT doctoral student Charles Roques-Carmes.

“This is something that might translate into applications for medical imaging, which are optical photon-starved, meaning the conversion of X-rays to optical light limits the image quality. In medical imaging, you do not want to irradiate your patients with too much of the X-rays, especially for routine screening, and especially for young patients as well,” said Roques-Carmes in a statement.

The approach used by Roques-Carmes and his colleagues applies advances in nanotechnology to existing materials. Patterns are created in scintillator materials at a length scale comparable to wavelengths of the light being emitted by the machine. This makes it possible to significantly alter the material’s optical properties.

In their study, the team made holes spaced apart by roughly one optical wavelength — about 500 nanometers (billionths of a meter) — in a scintillator. When calculating scintillation levels produced with the new configurations, a tenfold improvement was seen in emission. And with further fine-tuning, the scientists were able to show the possibility for 100 times improvement.

They expect their research will introduce new research efforts in nanophotonics, a field of study of how light interacts with materials that are structured at the nanometric scale. The development of computational simulations in other areas of the subject have allowed for rapid, substantial improvements in the development of solar cells and LEDs.

MIT professor Marin Soljacic says nanophotonics can help researchers tailor and enhance the behavior of light in medical imaging, and that the general theory and framework behind the team’s work helps in this endeavor by making modeling of the scintillation easier. “Now, this work, for the first time, opens up this field of scintillation, fully opens it, for the application of nanophotonics techniques. More generally, the team believes that the combination of nanophotonic and scintillators might ultimately enable higher-resolution, reduced X-ray dose and energy-resolved X-ray imaging.”

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