A review of small animal dosimetry techniques: image-guided and spatially fractionated therapy

Abstract

Research in small animal radiotherapy is a crucial step in clinical translation of novel radiotherapy techniques, either delivered as stand-alone treatment or in combination with other treatments, such as chemotherapy and immunotherapy. In order to efficiently translate preclinical findings to the clinical setting, preclinical radiotherapy must replicate clinical therapy in terms of mode of delivery as well as dose delivery accuracy as closely as possible. In this review article, we focused on the description of dosimetry tools for radiotherapy of small animals delivered with kilovoltage x-ray beams on image-guided irradiators and in a spatially-fractionated manner by means of microbeam therapy. The specifics of dosimetry of kilovoltage x-ray beam deliveries with small, often sub-millimeter, beams are highlighted, and suitable dosimeters, phantoms, and dose measurement and calculation techniques are reviewed. Future directions for accurate real-time high spatial resolution dosimetry of small animal irradiations are also discussed.