Christine Lys

Three Dimensional MR-Based Morphometric Comparison of Schizophrenic and Normal Cerebral Ventricles

Enlarged cerebral ventricles are consistently detected in patients suffering from schizophrenia. Several workers report more detailed association of this disease and particular brain areas. In order to assist these efforts at localization we define a tiled-out map of the ventricular surface, a template, based on specialized crest lines that we term: ridge curves. In this analysis we use this template to (1) average 3D MR-based ventricular surface images collected from 12 patients and 12 controls, and (2) locate the position of regularly occurring curvature maxima landmarks along the ridge curves. Statistical analysis of the locations of these curvature maxima landmarks indicate promising localization of a shape difference associated with schizophrenia in the frontal horn of the lateral cerebral ventricle.

Three-dimensional magnetic resonance-based morphometrics and ventricular dysmorphology in schizophrenia

BACKGROUND Recent methodological refinements in magnetic resonance (MR) imaging have led to brain averaging and morphometric approaches that are sensitive to subtle anatomical distinctions in schizophrenia. METHODS Using a novel morphometric technique for surface analysis, 48 selected landmarks of the rendered ventricular system were extracted and compared between the ventricles of 20 patients with schizophrenia and 20 normal subjects. RESULTS There was no significant difference in ventricular shape between groups, but significant (p = .015) and highly localized shape deformity was detected at the foramen of Monro and at the proximal temporal horn of the lateral ventricle of male (but not female) patients relative to controls. CONCLUSIONS Three-dimensional MR-based morphometrics complements established volumetric approaches and can detect minute shape deformities that may be associated with schizophrenia.

Increased prefrontal sulcal prominence in relatively young patients with unipolar major depression

Although several studies have reported ventricular enlargement and sulcal prominence in mixed samples of patients with affective disorders (unipolar and bipolar subtypes), it is not established if these findings extend to a homogeneous sample of relatively young patients with unipolar major depression ventricular:brain ratio (VBR) and prefrontal sulcal prominence (PSP). In the present study, measures of ventricle-brain ratio (VBR) and prefrontal sulcal prominence (PSP) were compared in patients with affective disorders (n = 24, mean age = 39), medical control subjects (n = 40), patients with schizophrenia (n = 101) on ventricular : brain ratio (VBR) and prefrontal sulcal prominence (PSP). No statistically significant differences were noted in VBR in the three groups. Both patient groups had significantly greater PSP than the medical control subjects but did not differ significantly from each other. The results of the present study extend the finding of prefrontal sulcal prominence, but not ventricular enlargement, to relatively young patients with unipolar depression. Furthermore, the results of the present study suggest that patients with schizophrenia and patients with affective disorders differ only slightly or not at all in brain morphology, at the level of resolution studied.

Risperidone for Treatment-Resistant Schizophrenia: Initial Clinical Experience in a State Hospital

Objective: To examine the efficacy of risperidone, a new antipsychotic with combined serotonergic-dopaminergic antagonism, in patients with treatment-resistant schizophrenia in state facilities. Methods: Brief Psychiatric Rating Scale (BPRS) evaluations were performed on 21 patients with schizophrenia who had received risperidone therapy for 10 weeks in a state facility. Results: Five patients showed a 20% reduction on their pretreatment BPRS score. A corresponding number of patients showed an increased BPRS score during treatment, and the remainder attained a modest reduction (2–17%) in symptoms on the BPRS. Conclusions: Although risperidone was an effective antipsychotic for patients with chronic treatment-resistant schizophrenia, only a subgroup of these patients achieved substantial clinical improvement over a 10-week period.

Clozapine plasma levels and dosing strategies in patients with treatment-refractory schizophrenia

Objective : To determine the effect on clinical response to clozapine of increasing the plasma levels of clozapine and its major metabolite N-desmethylclozapine in 19 patients with schizophrenia who had plasma clozapine levels ≤ 370ng/ml, a level previously determined to identify patients who were unlikely to have an adequate response to clozapine. Method : The dosage of clozapine was increased by 20% in 11 patients and left unaltered in the other eight patients. Clozapine and N-desmethylclozapine plasma levels were measured after six weeks at the higher dose. Results : Nine of the 11 patients in whom clozapine dosage was increased subsequently achieved plasma clozapine levels ≥ 370ng/ml. However, in this group of patients who already had partially responded to clozapine, increasing the dosage of clozapine did not produce additional clinical improvement. Conclusion : Clozapine plasma levels are useful in clinical practice to guide dosage strategies. However, these results suggest that increasing the dosage of clozapine to achieve plasma levels ≥ 370ng/ml is unlikely to produce further improvement in patients who have already achieved a partial response to clozapine at plasma levels ≤ 370ng/ml.