Orbitofrontal morphology in people at high risk of developing schizophrenia.
BACKGROUND
Abnormalities of orbitofrontal cortex (OFC) sulcogyral patterns have been reported in schizophrenia, but it is not known if these predate psychosis.


METHODS
Hundred and forty-six subjects at high genetic risk of schizophrenia, 34 first episode of schizophrenia patients (SZ) and 36 healthy controls were scanned and clinically assessed. Utilising the classification system proposed by Chiavaras, we categorised OFC patterns and compared their distribution between the groups, as well as between those high risk subjects who did, and did not develop schizophrenia. The relationship between OFC pattern and schizotypy was explored in high risk subjects.


RESULTS
We refined Chiavaras' classification system, with the identification of a previously unreported variant of OFC surface structure. There were significant differences in distribution of OFC patterns between high risk subjects who did or did not develop schizophrenia as well as between the first episode of schizophrenia group and healthy controls. Within the high risk group, possession of OFC Type III was associated with higher ratings on the Structured Inventory for Schizotypy (SIS) psychotic factor.


CONCLUSIONS
Our results suggest that OFC Type III is associated with psychotic features before the development of schizophrenia. Characterisation of OFC morphology may have a role in the identification of those at greatest risk of developing schizophrenia.
Chakirova
G
G
Imaging lab, Division of Psychiatry, University of Edinburgh, Royal Edinburgh Hospital, Kennedy Tower, EH10 5HF, Edinburgh, Scotland, UK. G.Chakirova@sms.ed.ac.uk
Welch
K A
KA
Moorhead
T W J
TW
Stanfield
A C
AC
Hall
J
J
Skehel
P
P
Brown
V J
VJ
Johnstone
E C
EC
Owens
D G C
DG
Lawrie
S M
SM
McIntosh
A M
AM
D000293:Adolescent; D000328:Adult; D016022:Case-Control Studies; D005260:Female; D005500:Follow-Up Studies; D005625:Frontal Lobe / Q000473:pathology*; D006801:Humans; D008279:Magnetic Resonance Imaging; D008297:Male; D011569:Psychiatric Status Rating Scales; D012307:Risk Factors; D012559:Schizophrenia / Q000145:classification / Q000175:diagnosis / Q000473:pathology*; D012565:Schizophrenic Psychology; D012919:Social Behavior; D055815:Young Adult