Positron tomography demonstrates frontal lobe hypometabolism in progressive supranuclear palsy

A regional analysis of cerebral glucose metabolism was carried out in 9 patients with progressive supranuclear palsy by using positron emission tomography with fluorodeoxyglucose as the tracer. A consistent metabolic map of frontal hypometabolism was found in 7 patients. Brain metabolism was normal in 1 subject and diffusely decreased in another. In the 7 patients with selective hypofrontality, motor and premotor areas were severely hypometabolic, while heteromodal association cortex and paralimbic regions were comparatively less affected. Although this pattern of frontal alterations, probably due to disconnection, appeared consistent with the clinical features of the disease, it proved difficult to correlate the metabolic maps with neuropsychological disturbances.