A. Versace

Anterior cingulate volumes in schizophrenia: A systematic review and a meta-analysis of MRI studies

OBJECTIVES Several MRI studies have investigated the anterior cingulate in schizophrenia, as this is a key region for emotional processing and higher executive performances. A systematic review of structural MRI studies and a meta-analysis were conducted to explore whether anterior cingulate volumes are abnormal in patients with schizophrenia. METHOD A systematic search strategy was used to identify eligible MRI studies. Thereafter, a meta-analysis was carried out by using a random effect model. Also, a meta-regression analysis was used to assess the influence of age, gender and slice thickness on effect sizes. RESULTS The meta-analysis was performed on seven studies. These results showed that the anterior cingulate volumes were significantly reduced in patients compared to healthy controls. Significant heterogeneity between these studies was observed. The meta-regression demonstrated that the effect size was significantly related only to slice thickness. CONCLUSIONS Our work confirmed the presence of abnormally reduced anterior cingulate volumes in schizophrenia. However, several methodological issues limited the interpretation of these findings. Among these were different MR acquisition parameters and the small size of the sample, which was mostly composed of chronic patients. Future MRI studies should be planned to better understand the functional expression of anterior cingulate structural abnormalities.

Decreased entorhinal cortex volumes in schizophrenia

BACKGROUND The entorhinal cortex is located in the medial temporal lobe and is involved in memory and learning. Previous MRI studies reported conflicting findings in schizophrenia, showing normal or reduced entorhinal size. OBJECTIVES To explore entorhinal cortex volumes in a large sample of patients with schizophrenia recruited from the geographically defined catchment area of South Verona (i.e. 100,000 inhabitants). We also investigated the size of hippocampus as part of the medial temporal lobe. METHODS 70 patients with schizophrenia and 77 normal controls underwent a session of MRI (TR=2060 ms, TE=3.9 ms, slice thickness=1.25 mm). Entorhinal and hippocampal volumes were explored using the Brains2 software. RESULTS A significant group effect was found for total entorhinal cortex but not for hippocampus, with patients suffering from schizophrenia having smaller entorhinal volumes compared to normal subjects (F=6.24, p=0.01), particularly on the right side (F=9.76, p=0.002). Also, the laterality index for entorhinal cortex was higher in normal individuals than in patients with schizophrenia (F=5.45, p=0.02). CONCLUSIONS Consistent with some of the previous reports, our study confirmed the presence of abnormally decreased entorhinal volumes, particularly on the right side, in a large number of patients with schizophrenia and also found altered asymmetry. This may play a major role in the psychopathology and cognitive disturbances of the disease. Future longitudinal MRI studies including high-risk subjects and drug-free, first-episode patients are crucial to further understand whether entorhinal cortex shrinkage is already present at the onset of the illness or appears as a consequence of the illness.

Normal pituitary volumes in chronic schizophrenia.

Pituitary volumes were shown to be abnormally large in pre- or first-psychotic episode patients and abnormally reduced in established schizophrenia by magnetic resonance imaging (MRI) studies. We present here the results of the second ever published MRI study exploring pituitary size in a large population of patients with chronic schizophrenia recruited from the geographically defined catchment area of South Verona, Italy. No significant differences for pituitary volumes were reported between 65 subjects with chronic schizophrenia and 65 normal individuals (mean age+/-S.D.=42.31+/-11.44 and 40.54+/-11.12 years). In contrast to Pariante et al. (2004), normal pituitary size was found in our population of chronic schizophrenia. Discrepancies between these two studies may partially be accounted by sample age and gender. Considering increased pituitary volumes in pre- or first-psychotic episode patients, we put forward the hypothesis that pituitary size may normalize or reduce with the progression of the illness as a result of reduced numbers of acute episodes and consequent diminished hypothalamus-pituitary-adrenal axis activity. To better test this hypothesis, future large MRI studies should investigate pituitary volumes in chronic schizophrenia longitudinally, also collecting pituitary hormones and cortisol, and comparing the effects of typical and atypical antipsychotics on pituitary size in a randomized trial.

Altered microstructure integrity of the amygdala in schizophrenia: a bimodal MRI and DWI study

BACKGROUND The amygdala plays a central role in the fronto-limbic network involved in the processing of emotions. Structural and functional abnormalities of the amygdala have recently been found in schizophrenia, although there are still contradictory results about its reduced or preserved volumes. METHOD In order to address these contradictory findings and to further elucidate the possibly underlying pathophysiological process of the amygdala, we employed structural magnetic resonance imaging (MRI) and diffusion weighted imaging (DWI), exploring amygdalar volume and microstructural changes in 69 patients with schizophrenia and 72 matched healthy subjects, relating these indices to psychopathological measures. RESULTS Measuring water diffusivity, the apparent diffusion coefficients (ADCs) for the right amygdala were found to be significantly greater in patients with schizophrenia compared with healthy controls, with a trend for abnormally reduced volumes. Also, significant correlations between mood symptoms and amygdalar volumes were found in schizophrenia. CONCLUSIONS We therefore provide evidence that schizophrenia is associated with disrupted tissue organization of the right amygdala, despite partially preserved size, which may ultimately lead to abnormal emotional processing in schizophrenia. This result confirms the major role of the amygdala in the pathophysiology of schizophrenia and is discussed with respect to amygdalar structural and functional abnormalities found in patients suffering from this illness.

Tridimensional reconstruction of cerebral volumetry in schizophrenia

Address: 1Department of Medicine and Public Health, Section of Psychiatry and Clinical Psychology, University of Verona, Italy, 2Verona-Udine Brain Imaging Program, Inter-University Center for Behavioural Neurosciences, University of Udine and *University of Verona, Italy, 3Department of Morphological and Biomedical Sciences, Section of Radiology, University of Verona, Italy and 4Department of Pathology and Experimental and Clinical Medicine, Section of Psychiatry, University of Udine, Italy * Corresponding author

3D reconstruction technique of perfusion MRI in schizophrenia

A pilot study was conducted to evaluate the usefulness of granisetron for the treatment of antidepressant induced sexual dysfunction in women. Twelve women with antidepressant induced sexual dysfunction (AISD) were assigned granisetron (n=5) or placebo (n=7) in a 14-day randomized, double-blind, placebo-controlled study. One participant in the granisetron group did not complete the study. Participants were assessed at baseline, day 7 and day 14 using the Feiger Sexual Function and Satisfaction Questionnaire and the Arizona Sexual Experience Scale. No statistical differences were measured at baseline or at endpoint between the granisetron or placebo group. This study did not produce evidence supporting the usefulness of granisetron in AISD.