functional Brain Imaging A brief introduction to functional Brain Imaging Dr John Clarkson

Quote: -the brain can look quite normal anatomically, despite the being quite marked abnormalities of function - These radiological investigations are like taking a digital photograph of the brain i.e. they show the static structure [anatomy] of the brain - not - how it actually works! X-RAYS MRI’s CAT Scans Computerized Axial Tomography Magnetic Resonance Imaging

functional Brain Imaging allows us to see how the brain actually works and whether there are areas of abnormal activity PET Scans f MRI’s SPECT Proton Emission Tomography Single Proton Emission Computerized Tomography functional Magnetic Resonance Imaging

functional Brain Imaging Nuclear Medicine studies rely upon injecting substances into the patient’s blood stream which have an affinity for the receptor sites (Neuro-receptors) contained within the cells of the brain (Neurons). * SPECT Scans utilize radio-active isotopes in studying brain function while PET Scans utilize radio- active labeled glucose molecules. These substances are differentially taken up by the brain’s neuro-receptor sites depending on the degree of neural (neuro-transmitter) activity occurring in the different regions of the brain . SPECT Scans are available and being used increasingly in Australia for the investigation of neurological and psychiatric disorders. ** functional MRI’s do not use Radioactive Isotopes; these investigations are very expensive and generally are only available in research institutes.

functional Brain Imaging - show how the brain actually works ! SPECT Scans fMRI’s PET Scans Frontal Lobe Parietal Lobe Temporal Lobe Inferior-Orbital (PFC) Occipital Lobe Cerebellum

functional Brain Imaging SPECT SCANS [Single Photon Emission Computerized Tomography]

SPECT Scans functional Brain Imaging show how our brain actually work ! (1) The brain is the only organ in the body not able to store energy. (2) The brain’s energy (mainly glucose) is derived from it’s circulation i.e. the cerebral blood flow.(CBF) (3) In psychiatric disorders regions of the brain are often dysfunctional & hence require excessive CBF to maintain their function - as with the thalamus in cases of Mood Disorders. Similarly, areas which are injured or dysfunctional - as in MBI or ADHD, have less activity and therefore utilise less CBF. (4) Injecting a patient with a radio-active isotope allows us to see what is happening within the patients brain & then compare it with a “normal” data base..

Brain Imaging SPECT Scans functional (1) Once the radioactive labelled tracer are injected into the patient’s blood they circulate through the brain, preferentially attaching to the brain’s neuro-receptors. (2) The rate of tracer uptake by a particular brain region is dependant upon how hard that area has to work i.e. its metabolism. (3) In psychiatric disorder's most regions of the brain have normal metabolism while others areas have undergone alteration in their neuro-transmitter composition giving rise to the patient’s symptoms such as depression, anxiety or anger & aggression. (4) Using modern camera and computer technology the rate of isotope uptake can be visualized in colour scales; data bases are now available to allow a comparison of a patient's brain with a so called ‘average’’ brain. functional Brain Imaging

Brain Imaging formulae Regional CBF Neuronal Metabolism NT activity

functional Brain Imaging - a modern SPECT Camera

Brainmatters - Denver, Colorado. Consultation Room - for discussion of SPECT Scan results with patient and family

functional Brain Imaging - SPECT Scan Applications Dementia Epilepsy Closed Head Injury Cerebrovascular Disease Neurological Disorders

Bipolar Spectrum Disorders functional Brain Imaging - SPECT Scan Applications SPECT Schizophrenia Illicit Drug Abuse “Pot’, ‘speed’ cocaine, ecstasy Anxiety Disorders OCD Panic Attacks GAD Mood Disorders Depression Bipolar Spectrum Disorders Psychiatric Disorders

Thank you The End f Brain Imaging A full introduction to understanding & interpreting SPECT is available on CD/DVD from this Web site or by attending the seminar in “A Journey through the Brain” Series Thank you The End