MRI assessment of gray and white matter distribution in Brodmann's areas of the cortex in patients with schizophrenia with good and poor outcomes

Abstract

Objective: High-resolution magnetic resonance imaging (MRI) was used to compare cortical gray and white matter and CSF volumes in schizophrenia patients with poor outcomes, schizophrenia patients with good outcomes, and healthy comparison subjects.

Method: T(1)-weighted, 1.2-mm-thick MR images were acquired for 37 patients with schizophrenia and 37 healthy, age- and sex-matched comparison subjects. The patients were assigned to subgroups with poor outcomes (N=13) and good outcomes (N=24) on the basis of clinical characteristics. Poor-outcome patients were those who were continuously hospitalized or completely dependent on others for basic needs, were unemployed, and had severe negative symptoms and severe formal thought disorder. The MR images were reoriented to standard position parallel to the anterior commissure-posterior commissure line and segmented into CSF, gray matter, and white matter tissue types. The tissue types were assigned to Brodmann's areas by using the Perry postmortem histological atlas, and tissue-type volumes in the three subject groups were compared.

Results: Compared to the healthy subjects, the overall patient group had a significantly smaller mean cortical gray matter volume and significantly larger mean CSF volume, especially in the frontal lobe and left temporal lobe. The smaller frontal lobe volume in schizophrenia was confirmed for unadjusted volumes and for volumes with adjustment for whole brain volumes. Compared to patients with good outcomes, patients with poor outcomes (Kraepelinian schizophrenia) had significantly smaller gray matter volumes in the temporal and occipital lobes, but no difference between groups was found for total frontal lobe volume. Only 21% of the healthy subjects had volumes 0.5 standard deviations below the mean for healthy subjects in any area of the frontal or temporal lobes, compared with 62% of poor-outcome patients.

Conclusions: Poor outcome in patients with schizophrenia may be associated with a more posterior distribution (posteriorization) of gray matter deficits across widely distributed cortical regions.