Volume reduction and altered sulco-gyral pattern of the orbitofrontal cortex in first-episode schizophrenia.
BACKGROUND
Although clinical and neuropsychological findings have implicated functional deficits of the orbitofrontal cortex (OFC) in schizophrenia, structural magnetic resonance imaging (MRI) studies of this region have yielded inconsistent findings. In addition, it remains elusive whether the OFC morphology in first-episode patients is related to their clinical features.


METHODS
MR images were acquired from 42 (24 males, 18 females) first-episode schizophrenia patients and 35 (20 males, 15 females) age-, gender-, and parental socio-economic status (SES)-matched healthy subjects. The OFC sub-regions (orbital gyrus and straight gyrus) were measured on contiguous 1-mm-thick coronal slices. The OFC sulco-gyral pattern was also evaluated for each subject. Furthermore, the relationships between OFC morphology and clinical measures were examined.


RESULTS
The volumes of the bilateral orbital gyri were significantly reduced in schizophrenia patients compared with healthy subjects, whereas the volumes of the straight gyri did not show differences between the groups. Among the schizophrenia patients, the volume of the left orbital gyrus was inversely correlated with their SES and illness duration. The OFC sulco-gyral patterns were significantly different between the patients and controls in the right hemisphere.


CONCLUSIONS
This study demonstrated morphologic abnormalities of the OFC in first-episode schizophrenia patients, which may have reflected neurodevelopmental aberrations and neurodegenerative changes during the first episode of the illness. Our findings also suggest that such brain structural changes are related to the social dysfunction observed in schizophrenia.
Takayanagi
Yoichiro
Y
Department of Neuropsychiatry, University of Toyama Graduate School of Medicine and Pharmaceutical Sciences, 2630 Sugitani, Toyama 930-0194, Japan. y-takayanagi@sky.707.to
Takahashi
Tsutomu
T
Orikabe
Lina
L
Masuda
Naohisa
N
Mozue
Yuriko
Y
Nakamura
Kazue
K
Kawasaki
Yasuhiro
Y
Itokawa
Masanari
M
Sato
Yoko
Y
Yamasue
Hidenori
H
Kasai
Kiyoto
K
Okazaki
Yuji
Y
Suzuki
Michio
M
D000328:Adult; D000704:Analysis of Variance; D001931:Brain Mapping; D016022:Case-Control Studies; D005260:Female; D007839:Functional Laterality / Q000502:physiology; D006801:Humans; D007091:Image Processing, Computer-Assisted / Q000379:methods; D008279:Magnetic Resonance Imaging; D008297:Male; D017397:Prefrontal Cortex / Q000473:pathology*; D011569:Psychiatric Status Rating Scales; D012559:Schizophrenia / Q000473:pathology* / Q000503:physiopathology; D013223:Statistics as Topic; D055815:Young Adult