Magnetic Resonance (MR) Advanced Neuroimaging

MR Perfusion is the MR technique allowing evaluation of cerebral blood volume (CBV) following the injection of gadolinium contrast media followed by MR imaging over time. This technique is often used in the further evaluation of tumours and stroke.

Susceptibility weighted imaging is a high resolution MR technique that is more sensitive than conventional imaging in detecting haemorrhagic (bleeding) lesions.

MR spectroscopy acquires metabolite information reflecting neuronal integrity and function from multiple brain regions and provides sensitive, non-invasive assessment of changes in neurochemical behaviour. It can be used to further characterise lesions such as tumours, epilepsy and other diseases such as schizophrenia and multiple sclerosis.

Diffusion weighted imaging is based on differences in diffusion of water molecules within the brain and is very sensitive in the detection of stroke.

Diffusion tensor imaging (DTI) is a form of diffusion weighted imaging and allows better evaluation of white matter fibre tracts by taking advantage of the directional diffusion of water in the human brain. It is very useful in the evaluation of brain tumours and other neurological diseases.

Functional MRI (fMRI) is a specialised MRI scan that measures the change in blood flow related to a neuronal activity. Patients are asked to perform specific tasks eg finger tapping, word association with pictures etc during the MRI scan and activation centres of the brain can be seen. This is useful particularly in the pre-operative evaluation of brain tumours and epilepsy.

Arterial Spin Labelling (ASL) is a new non-invasive, non-contrast method of calculating cerebral brain perfusion by imaging pre magnetised proximal blood as it enters the brain. The associated signal is proportional to cerebral blood flow.

No MRI techniques use ionizing radiation (X-rays), although there are other risks associated with MR imaging. These will be discussed with you by your doctor and your medical imaging technologist.