A Proton Magnetic Resonance Spectroscopy Imaging Study On Prefrontal Lobe And Hippocampus In Adolescence-onset Schizophrenia

BackgroundSchizophrenia is one of the major forms psychotic disorders. The causes of schizophrenia are not well understood. Magnetic resonance spectroscopy (MRS), a noninvasive neuroimaging approach has been applied to investigate the etiology of schizophrenia. To identify the possible alterations of brain function in prefrontal lobe and hippocampus in adolescence-onset schizophrenia using proton magnetic resonance spectroscopy (~1H-MRS).Subjects and methodsA 1.5-T nuclear magnetic resonance machine was used to test 21 patients(13-17years;mean age±SD,15.9±1.9years;12boys,9girls) and 20 comparison subjects (14-17years;mean age±SD,15.8±1.6years;10boys,10girls).~1H-MRS was carried out using PRESS for spatial localization (repetition time = 1500 msec, echo time =135 msec, repetition time = 1500 msec, average number = 192, acquire time =4min48sec). The T2-weighted series was used to prescribe an 15-cm 3 voxel in prefrontal lobe and hippocampus. CHESS was used to provide maximum water suppression. The NAA, Cho and Cr were measured and the ratios of NAA/Cr and Cho/Cr were determined. Spectral data were analyzed using SPSS11.0 software.ResultsThe NAA and NAA/Cr ratios in left prefrontal lobe in patients with adolescence-onset schizophrenia were lower than those in normal controls (NAA: t=2.623, P <0.05; NAA/Cr: t=2.101, P <0.05) ; the Cr in right prefrontal lobe in patients was higher than that in normal controls (t=-2.039, P<0.05) ,while NAA/Cr and Cho/Cr in right prefrontal lobe in patients were lower than those in normal controls (NAA/Cr: t=3.660, P<0.05; Cho/Cr: t=3.226,P<0.05) .In left hippocampus, the NAA/Cr ratio in patients with adolescence-onset schizophrenia was lower than that in controls (t=2.135, P<0.05) .ConclusionsOur results confirm that patients with adolescence-onset schizophrenia have damage of neuronal integrity and dysfunction in the bilateral prefrontal lobe and left hippocampus. The elevated Cr in adolescence-onset schizophrenia shows reducedcellular energy demand in right prefrontal lobe and may index affecting glial density or function integrity. The results suggest that there is a biological continuum between adolescence-onset schizophrenia and adult-onset schizophrenia. This study provides a new evidence to understand the neurodevelopmental etiology of schizophrenia.