Mini synchrotron enables biomedical imaging research

Lyncean Technologies has developed the Munich Compact Light Source (MuCLS) for the Munich School of BioEngineering, based at the Technical University of Munich (TUM). The light generated by the MuCLS can be used to increase contrast in techniques that can be applied to real-world medical diagnosis problems, thus enabling groundbreaking biomedical imaging research.

The MuCLS is a mini synchrotron capable of creating a nearly monochromatic, energy tuneable X-ray beam. X-rays are generated via inverse Compton scattering when an electron bunch circulating at 65 MHz in a miniature storage ring collides with high power laser pulses stored in a resonant optical cavity. The X-ray source is thus able to deliver synchrotron-quality data for a wide variety of laboratory experiments.

According to the TUM team, the mean flux measured when the MuCLS was commissioned in 2015 was in excess of 1 x 10¹⁰ photons/s at 35 keV. Increasing the X-ray flux is desirable to shorten data acquisition times and to increase the signal-to-noise ratio of measurements. In April 2017, the high-power laser system was upgraded on the MuCLS, which increased the stored laser power in the optical cavity of the system from 100 to >300 kW. The X-ray flux at 35 keV was subsequently measured to be in excess of 3 x 10¹⁰ ph/s at 35 keV.

In a study published in the journal EPL in November 2016, the TUM team presented the first grating-based multimodal tomosynthesis images of a human breast slice acquired via a CLS to investigate the possibilities of improved breast cancer diagnostics. The CLS’s relatively large partially coherent X-ray beam was found to be particularly suitable for the investigation of preclinical applications of grating-based phase-contrast and dark-field imaging.

In a February 2017 study, published in Scientific Reports, the MuCLS was used to reduce the contrast media in iodine- and gadolinium-based X-ray coronary angiography through the use of quasi-monochromatic spectra. A reduction in iodine-based contrast media is useful for patients who present with chronic renal insufficiency or with severe iodine allergy, who could benefit from a reduced contrast agent concentration achieved through, for example, the application of a mono-energetic X-ray beam.

Finally, in a July 2017 study from Scientific Reports, the researchers demonstrated propagation-based X-ray phase-contrast imaging in known phantoms and the lungs and airways of a mouse. They observed that edge enhancement and quantitative phase retrieval were successfully performed in the known phantom, while the images of the mouse show the potential for live bio-imaging research studies that capture biological function using short exposures.

Pictured: The Munich Compact Light Source (MuCLS). Image has been cropped from the original, and is presented here courtesy of Elena Eggl et al under CC BY 4.0