Introduction

Intracranial mass lesions are a broad and very disparate group of pathological conditions ranging from brain tumours to non-neoplastic conditions such as abscess or neurocysticercoses. Intracranial mass lesions are a significant health problem and present several imaging challenges and radiology has played an integral role in the diagnosis, monitoring, and treatment planning of intracranial masses. MRI in particular, offers superior soft-tissue contrast over other cross-sectional imaging techniques allowing for better visualisation of subtly infiltrated or disrupted parenchymal architecture, has emerged as the imaging modality of choice. However, in many cases, conventional MRI which provides useful structural findings are not enough for an accurate diagnosis.

Neuro-oncological imaging has evolved from a purely anatomy-based discipline to one that incorporates morphologic abnormality with physiologic alterations, cellular metabolism, and hemodynamics. Tremendous progress and widespread clinical use of physiology-based MR imaging have become an essential part of the diagnostic armamentarium to diagnose, guide surgery, monitor therapy response, and predict prognosis of patients with a brain tumour. The current most commonly used advanced techniques include diffusion-weighted imaging(DWI), MR Spectroscopy (MRS), Perfusion-weighted imaging (PWI)and Susceptibility weight imaging (SWI). These methods have played a pivotal role in the transition of clinical MR imaging from a purely morphology-based discipline to one that combines structure with function.

Integration of diagnostic information from above mentioned advanced MR imaging techniques can evaluate different tumour types, predict tumour grade, improve the classification accuracy, further differentiate tumour from non-neoplastic lesions, serially and noninvasively monitor tumour progression, and monitor the efficacy of therapy.

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Atul Kumar Singh