Molecular Imaging in Diagnosis and Treatment of Brain Tumours

We provide an overview of the current status of brain tumours, their incidence and possible risk factors. The current treatment options, including surgery, immunotherapy, chemotherapy, radiotherapies and particle therapy are discussed, with a focus on how this can be informed by imaging techniques. Delivery of agents to the central nervous system is a key consideration; various strategies for penetrating (chemical modification, ultrasound) and circumventing (convection enhanced delivery) the blood–brain barriers are discussed. The most commonly used techniques for diagnosis of brain tumours (biopsy, magnetic resonance imaging, positron emission tomography) are described, along with less well-established techniques such as optical imaging, optical coherence tomography, photoacoustic imaging, ultrasound, X-ray computed tomography (CT), single photon emission computed tomography (SPECT) and Raman spectroscopy. We consider the aspects which can be highlighted by different methods, including an appraisal of their strengths and limitations, with discussion on the potential for targeting, and what information can be gained by imaging for both diagnosis and disease progression. The future potential for imaging in the diagnosis and treatment of brain tumours is then considered, with a focus on which properties are desirable for novel imaging agents.