Anomalous asymmetry of fusiform and parahippocampal gyrus gray matter in schizophrenia: A postmortem study.

OBJECTIVE: Anomalies of structure and asymmetry of the parahippocampal gyrus (origin of the perforant path input to the hippocampal formation in the medial temporal lobe) have been shown in some postmortem studies of schizophrenia, but previous studies have not included the fusiform gyrus (which may have a role in facial recognition and naming), adjacent to the parahippocampal gyrus on the ventral occipitotemporal surface. METHOD: The volumes of gray matter in the left and right parahippocampal and fusiform gyri were assessed with a stereological point-counting technique in the temporal lobes from formalin-fixed brains of 27 comparison subjects and 31 patients with schizophrenia. Age was a covariate and gender was a factor in the analysis. RESULTS: In relation to the comparison subjects, the schizophrenic patients (both sexes) had lower volumes of both the parahippocampal and fusiform gyri on the left side. For both structures a left-greater-than-right volume asymmetry was present in the comparison subjects, but this asymmetry was reversed in the parahippocampal and fusiform gyri of the schizophrenic patients. A sex difference was present with respect to age at onset-degree of anomaly of asymmetry for both gyri increased with age at onset in men but not in women. CONCLUSIONS: The findings add substance to the view that the sex-related dimension of symmetry/asymmetry is integral to the disease process in schizophrenia and draw attention to the fusiform gyrus as a structure of particular interest in relation to disturbances of identification and naming in psychosis.

The size and fibre composition of the corpus callosum with respect to gender and schizophrenia: a post-mortem study.

In this study the cross-sectional area (in n = 14 female controls, 15 male controls, 11 female patients with schizophrenia, 15 male patients with schizophrenia) and fibre composition (in n = 11 female controls, 10 male controls, 10 female patients with schizophrenia, 10 male patients with schizophrenia) of the corpus callosum in post-mortem control and schizophrenic brains was examined. A gender x diagnosis interaction (P = 0.005) was seen in the density of axons in all regions of the corpus callosum except the posterior midbody and splenium. Amongst controls, females had greater density than males; in patients with schizophrenia this difference was reversed. A reduction in the total number of fibres in all regions of the corpus callosum except the rostrum was observed in female schizophrenic patients (P = 0.006; when controlling for brain weight, P = 0.053). A trend towards a reduced cross-sectional area of the corpus callosum was seen in schizophrenia (P = 0.098); however, this is likely to be no more than a reflection of an overall reduction in brain size. With age, all subregions of the corpus callosum except the rostrum showed a significant reduction in cross-sectional area (P = 0.018) and total fibre number (P = 0.002). These findings suggest that in schizophrenia there is a subtle and gender-dependent alteration in the forebrain commissures that may relate to the deviations in asymmetry seen in other studies, but the precise anatomical explanation remains obscure.

Anomalies of cerebral asymmetry in schizophrenia interact with gender and age of onset: a post-mortem study.

In a post-mortem study of cerebral asymmetry in schizophrenia it was found that asymmetry of the length from the frontal pole to the central sulcus measured dorsally over the external surface of the brain on both hemispheres, showed a gender x diagnosis interaction (p = 0.002). Female controls had a left-greater-than-right asymmetry, and the male controls had a right-greater-than-left asymmetry. This pattern was reversed in schizophrenia. The converse effect was observed on a similar measure of the occipito-parietal lobes (p = 0.028). Significant changes were not seen in measures taken around the lateral surface of the hemispheres. Further, within the patient group, the frontal lobe asymmetry was related to age of onset such that leftward asymmetrical brains were associated with a later age of onset than rightward asymmetrical brains (p = 0.0463 for the females; p = 0.0162 for the males). The occipito-parietal asymmetry was not related to age of onset. We conclude that the asymmetry of the relative distribution of tissue between frontal and posterior regions of the hemispheres is altered in schizophrenia. The findings also suggest that there is an interaction between gender and cerebral asymmetry that is critical in determining age of onset.

Acinic cell carcinoma in Northern Ireland: a 10-year review.

12 cases of acinic cell carcinoma diagnosed in Northern Ireland from 1942 to 1982 on which there was at least 10 years' follow-up were reviewed, by pooling cases from all regional pathology laboratories. Clinical findings at presentation were established from case notes, together with details of eventual clinical outcome. Sections were examined to determine tumour size, morphological pattern and cytological constitution, the presence or absence of cytological atypia, mitotic activity, lymphocytic and desmoplastic responses, and to assess for infiltrative margins and adequacy of excision. The tumours arose in 8 females and 4 males, aged 22 to 86 years at presentation. Eleven tumours were in the parotid, one in the soft palate. Two patients suffered local recurrence, both more than 7 years after diagnosis. Five patients had regional lymph node metastasis, four at presentation. No patient suffered haematogenous metastasis or died of tumour. Of the features examined, incomplete excision increased the risk of local recurrence. While numbers are small, the acinic cell carcinoma in Northern Ireland is an unpredictable low-grade malignant tumour which is capable of recurrence and metastasis. Adequate excision at presentation appears to be the most appropriate therapy.