TECHNOLOGY PROGRAMME – Radiation Metrology for Applications

Project leader: Teemu Siiskonen    Personnel

The increasing frequency of computed tomography (CT) medical imaging calls for efficient patient exposure optimization. This optimization aims at as low patient dose as possible, with the constraint that the required diagnostic information must be obtained from the acquired CT image.

Novel detectors that can detect single photons and their energies have been developed and tested. These detectors include different scintillator materials combined with Si photodiode arrays and pixel detectors as well as CdTe pixel detectors. The detectors are read using the technology developed for CMS experiment at CERN. Together with advanced data processing and image reconstruction algorithms developed in the project high detection efficiency, excellent image quality and lower patient doses are achievable. Further applications can be found in Boron Neutron Capture Therapy (BNCT). The detectors can be used to detect particle radiation (e.g. alpha particles, electrons or protons) as well, widening the range of applications where these detectors can be used.

The feasibility of these detectors to be used in modern radiotherapy quality assurance (beam profiles and uniformity) will be studied, too. In particular in external beam radiotherapy technical advances in treatment equipment have led to a situation where the traditional measurement methods are no longer capable of providing reliable and accurate dose information. This may, and has, lead to a situation where the dose delivery to the tumor can be in error by such a large amount that threatens the tumor control or may lead to life-threatening complications if healthy tissues surrounding the target volume receive too large doses.