WP 3: Dosimetry Heart Diagnostics
Whole-body dose distribution after application of various examination procedures for heart diseases with good prognosis
The diagnosis and forecasting of heart insufficiency is supported by modern multimodal imaging processes, and differentiation between coronary and myocardial diseases is paramount for this question. Repeated imaging is performed for many patients. Coronary angiography may still be considered the gold standard. The early diagnosis of coronary heart diseases, however, is increasingly characterized by multimodal concepts (CT/CTA, SPECT/CT and PET/CT). For these types of examinations the patients are partly exposed to considerable radiation doses, similar to coronary angiography. The resulting organ doses will be evaluated for the estimation of late health effects and the personalized optimization of the examination procedure. The comparison between the dose distributions of PET/CT and PET procedures will be of special interest for this project since the short-lived PET radiopharmaceuticals do not only accelerate the examinations but also reduce the radiation exposure. Existing methods (as coronary angiography) and methods under development (as PET/CT or heart CT) are supposed to be investigated and compared with regards to radiation exposure and diagnostic significance.
For patients with existing records of imaging parameters of the heart examination and a three-dimensional anatomic view (CT), dose distributions due to external exposures can be simulated and no specific measurements are required. Internal exposures need to be evaluated via biokinetic model calculations and activity measurements. Thus the questions that need to be addressed are the following: (1) which dose (distribution of organ dose values) is associated with the various kinds of examinations for heart diseases, dependent on patient parameters? (2) For individual patients, how does the diagnostic significance depend on the applied dose?