Anatomical imaging of the piriform cortex in epilepsy.

The piriform cortex is a distinct brain region that plays a key role in the sense of smell. The piriform cortex is the major part of primary olfactory cortex and has broad connections that extend beyond the olfactory regions into limbic and fronto-temporal cortical networks. Numerous studies have described these anatomical connections via microscopic imaging and tracer studies. More recently, macroscopic anatomical imaging studies have demonstrated changes in the piriform cortex in humans with focal epilepsy as well as in animal models, suggesting this brain region can play a critical role in epileptogenesis. This review examines the imaging methods and techniques that have been most informative, leading to our current understanding of the anatomy and subdivsions of the piriform cortex as well as its connections to other brain structures, and the abnormalities that can be detected in the setting of epilepsy.