Magnetic resonance imaging (MRI) is one of the most common diagnostic modalities used in veterinary neurology and neurosurgery. MRI scans are an essential component of the comprehensive management of central nervous system neoplasms in companion animals. Because of the popularity and widespread use of MRI, veterinary pathologists and anatomic pathology trainees can benefit from understanding the fundamentals of MRI scans and how they can be applied to complement diagnostic neuropathology. Here, we review basic principles of MRI generation and terminology and discuss diagnostic imaging and correlative gross neuropathologic features of intracranial neoplasms of dogs and cats. As an exhaustive review of the MRI characteristics of the neoplasms reported to affect the central nervous system of dogs and cats is beyond the scope of this article, we will focus on the most commonly diagnosed intracranial tumors in these species.
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