Imaging of parasellar lesions

The sellar and parasellar region is an anatomically complex area that represents a crucial cross-road of important adjacent structures, e.g. orbits, cavernous sinus and its content, polygon of Willis, hypothalamus through the pituitary stalk and dural reflections forming the diaphragm sellae and the walls of the cavernous sinuses. Although the cavernous sinus represents the most relevant parasellar structure, from the practical and clinical point of view all the structures that surround the sella turcica can be included in the parasellar region. CT and, mainly, MRI are the imaging modalities to study and characterise the normal anatomy and the majority of processes in this region. We present a practical short review of the most relevant CT and MRI characteristics, such as location, nature of contrast enhancement and presence of cystic components, together with clinical findings, which permit differentiation of the most frequent and less common lesions found in the parasellar region. Learning objectives: - A short review of the anatomy and clinical symptoms related to the parasellar region. - Radiological characterisation, mainly by MRI, of the many lesions that alter the structure and function of sellar and parasellar anatomy. - Description of the MRI features that permit differentiation among less common lesions.