Dose-Efficient X-ray Imaging Method Extends Observation Time of Small Organisms

Researchers at the Karlsruhe Institute of Technology (KIT) have developed an innovative X-ray imaging method that significantly extends the observation time of living cells and organisms. Traditionally, X-ray imaging's ionizing effect limited observation periods due to potential genetic material damage. However, the new method, developed by KIT's Laboratory for Applications of Synchrotron Radiation, employs a combination of X-ray phase contrast, a Bragg magnifier, and a photon-counting detector.

Conventional X-ray images of soft tissue lack contrast, but phase contrast methods enhance image clarity while reducing radiation dose. The challenge arises with higher resolution, requiring a higher dose and decreasing detector efficiency. The KIT researchers tackled this by directly enlarging the X-ray image using a Bragg magnifier before detection. This approach enables the use of highly efficient large-area detectors, enhancing the resolution to about 1 micrometer.

The novel method, described in Optica recently, achieves maximum dose efficiency for X-ray phase contrast at an energy level of 30 kiloelectron-volts. This efficiency allows for significantly longer observation times of small living organisms with micrometer resolution. In a pilot study with parasitic wasps, the researchers observed the creatures within their host eggs for over 30 minutes.

The new imaging system holds promise for applications in biology, biomedicine, and materials sciences. Its gentle three-dimensional histological investigation of biopsy samples showcases potential biomedical applications. The researchers plan to refine the setup, expanding the field of view and improving mechanical stability for extended measurements.