**1. Introduction**

Among primary brain and central nervous system tumors in adults, meningiomas are the most common, accounting for 36.4% of all, followed by pituitary tumors (15.5%) and glioblastoma (WHO Grade IV) (15.1%), which is the most malignant primary brain tumor. Other types are nerve sheath tumors (8.1%), all other astrocytomas (5.7%), lymphoma (2%), ependymal tumors

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(1.9%), oligodendrogliomas (1.6%), embryonal tumors (1.1%), oligoastrocytic tumors (0.9%), and all other less frequent tumors (11.7%) [1].

Imaging has a fundamental role in intracranial tumor management. Magnetic resonance imaging (MRI) is the imaging modality of choice for establishing diagnosis, classification, surgical planning, and post‐treatment follow‐up. The latest MRI techniques, namely diffu‐ sion, perfusion, and spectroscopy, offer more than the anatomical information that conven‐ tional imaging provides. Diffusion allows the assessment of water displacement within tissue. Diffusion tensor imaging permits the mapping of axonal organization. Perfusion MRI is a technique for the assessment of cerebral perfusion. Dynamic susceptibility contrast imaging (DSC‐MRI) perfusion technique is currently the most widely used and allows the calculation of relative cerebral blood volume (rCBV) and relative cerebral blood flow (rCBF). MR spectroscopy, with single‐voxel or multi‐voxel techniques, can detect metabolites within tissue such as N‐acetyl aspartate (NAA), choline‐containing compounds (Cho), myoinositol (mI), lactate (Lac), creatine (Cr), and other molecules. However, no tumor‐specific metabolite has been recognized to date.

Although the discrimination between intra‐axial and extra‐axial lesions is relatively straight‐ forward, for the accurate discrimination of the variety of intra‐axial tumors of several difficulties exist. This is of paramount importance for timely and appropriate patients' management. Herewith, we provide an overview of the latest MR techniques for the differ‐ ential diagnosis of intra‐axial tumors.
