Positron Emission Tomography in Schizophrenia: A New Perspective

PET is an important functional imaging technique that can be used to investigate neurotransmitter receptors and transporters directly by mapping human brain function. PET is increasingly being used greatly to advance our understanding of the neurobiology and pathophysiology of schizophrenia. Methods: This review focuses on the use of PET tracers and kinetic modeling inidentifyingregionalbrainabnormalitiesandregionsassociated with cognitive functioning in schizophrenia. A variety of PET tracers have been used to identify brain abnormalities, including 11C, 15O-water, 18F-fallypride, and L-3,4-dihydroxy-6-18F-fluorophenylalanine ( 18 F-FDOPA). Results: Some studies have used compartmental modeling to determine tracer binding kinetics. The most consistent findings show a difference in the dopamine contentintheprefrontalcortex,anteriorcingulate gyrus,andhippocampus between healthy controls and patients with schizophrenia. Studies also show a higher density of D2 receptors in the striatum and neural brain dysconnectivity. Conclusion: Future investigations integrating clinical, imaging, genetic, and cognitive aspects are warranted to gain a better understanding of the pathophysiology of this disorder.