Mini-beams and their applications to brain irradiations

Whereas the development and introduction of computed tomography and of nuclear magnetic resonance have allowed early diagnoses of brain tumours to be performed, and also a much more precise tumour location by stereotactic methods, this thesis in medicine addresses the use of mini-beams in external radiotherapy. After having recalled these developments, the author presents beam characteristics and formation, the additional collimation system, and dosimetric sets (dosimetric films, thermoluminescence device, ionisation chamber, semiconductors). Then, she describes and reports the performance of on-axis dose measurement (theoretical aspects, experimental method, curve standardisation), and of off-axis dose measurement (profile curves, isodose curves, study of the collimation system). She reports a comparison with other irradiation methods, and an analysis of published data