Imaging of cerebral blood flow and metabolism.
OBJECTIVE
To review the techniques for imaging cerebral blood flow and metabolism following injury to the brain.


RESULTS
Xenon enhanced computerized tomography (Xenon CT), CT perfusion and single photon emission CT provide measurements of cerebral perfusion, while positron emission tomography (PET), and magnetic resonance imaging and spectroscopy (MRI and MRS) are able to assess both perfusion and cerebral metabolism. Xenon CT and CT perfusion are readily available and have proved useful in a variety of causes of brain injury. PET is an extremely useful research tool for defining cerebral physiology, but is limited in its availability. Despite the continuing development of MRI and MRS imaging, the scanning environment remains hostile for critically ill patients, and further research is required before the techniques become generally available.


CONCLUSIONS
Imaging of cerebral blood flow and metabolism has been shown to be useful following a variety of causes of brain injury, as it can help to define the cause and extent of injury, identify appropriate treatments and predict outcome. Imaging based on CT techniques (Xenon CT and CT perfusion) can be implemented easily in most hospital centres, and are able to provide quantitative perfusion data in addition to structural images.
Coles
Jonathan P
JP
University Department of Anaesthesia, Addenbrooke's Hospital, Cambridge, UK. jpc44@wbic.cam.ac.uk
D001776:Blood Circulation Time; D001921:Brain / Q000098:blood supply* / Q000378:metabolism*; D001927:Brain Diseases / Q000175:diagnosis* / Q000000981:diagnostic imaging / Q000378:metabolism; D002560:Cerebrovascular Circulation; D038524:Diffusion Magnetic Resonance Imaging; D019788:Fluorodeoxyglucose F18; D005947:Glucose / Q000378:metabolism; D006801:Humans; D008279:Magnetic Resonance Imaging / Q000379:methods; D009682:Magnetic Resonance Spectroscopy / Q000379:methods; D015609:Organotechnetium Compounds; D010100:Oxygen / Q000378:metabolism; D010104:Oxygen Radioisotopes; D010477:Perfusion; D049268:Positron-Emission Tomography; D019275:Radiopharmaceuticals; D013113:Spin Labels; D015899:Tomography, Emission-Computed, Single-Photon; D036542:Tomography, Spiral Computed; D014057:Tomography, X-Ray Computed / Q000379:methods; D014978:Xenon
D015609:Organotechnetium Compounds; D010104:Oxygen Radioisotopes; D019275:Radiopharmaceuticals; D013113:Spin Labels; D019788:Fluorodeoxyglucose F18; D014978:Xenon; D005947:Glucose; D010100:Oxygen