Christin Gasser
Christian Gasser
Engineer ETH, Automatician EFZ, web technologies enthousiast and bike traveller who likes to discover new horizons

Exploring X-Ray Imaging: Hand-in Exercises from the Biomedical Imaging Course.

During the biomedical imaging course, I explored imaging techniques used in medical settings. Three weeks of the course were dedicated to X-ray imaging. In addition, one week exercise session was dedicated to radiotracer-based nuclear imaging techniques in conjunction with X-ray tomographic scans.

Each week, we completed hand-in exercises that required us to fill in missing parts of code for simulations and analysis. By completing the hand-in exercises and analyzing the simulations, I learned about the underlying principles of X-ray technology, which can be applied to various fields beyond biomedical imaging. Here is a short description of four hand-in we did:

  1. Introduction: understanding physical quantities and their links (voltage and photon energies), simulating projection of a numerical model, and simulating digital subtraction angiography, which extracts only data about blood vessels using contrast agents.
  2. Tomographic reconstruction (CT scan): creation of a reconstruction algorithm in order to make volumes from 2D scans using the backprojection technique. We also simulated filtering and interpolation techniques in order to understand the sources and consequences of reconstruction artifacts
  3. Scan quality: simulating of different factors that impact the quality of the scan, such as scan time, number of scans for the reconstruction, and moving objects. These factors affect the visibility and accuracy of the reconstructed image
  4. Positron emission imaging: positron emission imaging, consists of measuring gamma rays emitted by a radioactive compound in a patient. This allows for imaging tumour activity. The reconstruction algorithm for positron emission tomography (PET) is similar to X-ray tomography (up to a few adaptations) but requires an attenuation artefact correction using prior X-ray scan data. We simulated and implemented this correction algorithm.