Brain effects observed in the canine healthy tissue tolerance studies for BNCT with borocaptate sodium at the epithermal neutron beam of the HFR, Petten

Before the first clinical trails of BNCT with borocaptate sodium (BSH) on patients suffering from malignant brain tumours can be performed at the epithermal neutron bean of the HFR Petten, the tolerance of healthy tissue exposed to this beam has to be determined. Therefore irradiation experiments are currently being performed on beagle dogs at different mean blood 10B concentrations. To monitor radiation induced brain damage after irradiation, a method has to be employed which provides sufficient sensitivity for detecting radiation induced damage to tissue. Magnetic Resonance Imaging (MRI) is a non-invasive method which yields excellent discrimination between grey and white matter. Information on the integrity of the blood-brain-barrier can be obtained by using paramagnetic contrast agents like Gadolinium-DTPA (Gd-DTPA). This paper summarizes the results of the MRI's performed on the irradiated beagle dogs up to August 1992 and compares these results with the findings of histopathology