Quantitative Evaluation of the Canine Brain Using Computed Tomography

Abstract

Methods were developed for the quantitative evaluation of the canine brain using computed tomography (CT). Sixteen studies in 10 adult Beagle dogs were used to define the precision for densitometry and dynamic studies in the normal canine brain. For various regions of the brain, intra-animal and inter-animal variability was determined for normal tissue CT number, contrast enhancement and parameters relating to blood flow and blood volume. High precision was obtained for densitometry within and among animals when evaluated over a 9 mo. period. Both intra- and inter-animal variability in dynamic measurements was relatively large between studies, but hemispheric comparisons within a given study and between studies showed high precision. These methods can be used to evaluate morphologic and physiologic changes in the canine brain following radiation or other cytotoxic treatments [for malignant brain tumors].