Previous studies of target-cancellation performance in visuospatial neglect patients have reported lateral (left–right) and radial (near–far) gradients of attentional ability. The purpose of the ...present study was to replicate the reported attentional gradients in peripersonal space (within arms reach) and to examine whether lateral gradients of detection also appear in extrapersonal space (beyond arms reach), using equivalent tasks with no manual requirement. The relationship between radial gradients in peripersonal space and neglect severity (degree of lateral gradient) in extrapersonal space was also of interest. Right-hemisphere stroke subjects, with and without neglect, and healthy control subjects named visual targets on scanning sheets placed in peripersonal and extrapersonal space. The neglect group showed lateral gradients of increasing target detection from left to right in both peripersonal and extrapersonal space, which were not evident in the performance of either of the control groups. Double dissociations of neglect severity in peripersonal and extrapersonal space were also found in analyses of individual performance. Lesion analyses showed that peripersonal neglect was related to dorsal stream damage and extrapersonal neglect was related to ventral stream damage. Group analyses showed no significant radial gradients in peripersonal space in the three groups. In addition, while analyses of some individuals found significant near–far and far-near radial gradients, there was no correlation between radial gradients in peripersonal space and neglect severity in extrapersonal space. These results are discussed in terms of theorised hemispheric mechanisms of spatial attention and the relationship of neglect in the two co-ordinate spaces to the extent and location of damaged neurons in the right hemisphere.
The basal ganglia may contribute to extrapyramidal movement disorders, affective disturbances, and cognitive deficits in schizophrenia. Basal ganglia volumes are putatively affected by antipsychotic ...medications. The purpose of this study was to determine the long-term effects of risperidone treatment in a cohort of first-episode patients with schizophrenia.
The subjects were 30 patients with first-episode schizophrenia, 12 patients chronically treated with typical antipsychotics, and 23 healthy comparison subjects. They were scanned by magnetic resonance imaging at baseline. The first-episode patients received 1 year of continuous risperidone treatment, after which they and the comparison subjects were rescanned. Caudate, putamen, and globus pallidus volumes were determined from coronal images.
The baseline caudate, putamen, and globus pallidus volumes were significantly larger in the chronically treated patients than in the untreated first-episode subjects and comparison subjects. These volumes did not differ between the first-episode patients and healthy comparison subjects. Basal ganglia volumes were unchanged after 1 year of exposure to risperidone in the first-episode subjects. Extrapyramidal movement disorders were present in the majority of chronically treated patients and more than one-third of the never-medicated first-episode patients at baseline.
This group of first-episode patients did not exhibit abnormalities of basal ganglia volumes, nor were basal ganglia volumes affected by exposure to risperidone. Movement disorders were observed in both first-episode and chronically treated patients, suggesting effects of both illness and medications.
Abstract Background Previous studies have reported that hippocampal volumes correlate with symptom severity in schizophrenia. This longitudinal study measured changes in symptoms and hippocampal ...volume in patients switched from typical antipsychotics to olanzapine. Methods MRI scans were acquired from patients with chronic schizophrenia ( n = 10) and healthy volunteers ( n = 20). At baseline, patients were treated with typical antipsychotics for at least one year, then switched to olanzapine, and rescanned approximately one year later. Results Olanzapine treatment resulted in no significant change in right or left hippocampal volume. Individual changes in right hippocampal volume correlated significantly with changes in symptoms. Conclusions Hippocampal volume change may serve as a marker of symptom change in patients on olanzapine.
Background
: A definitive diagnosis of multiple sclerosis (MS), as distinct from a clinically isolated syndrome, requires one of two conditions: a second clinical attack or particular magnetic ...resonance imaging (MRI) findings as defined by the McDonald criteria. MRI is also important after a diagnosis is made as a means of monitoring subclinical disease activity. While a standardized protocol for diagnostic and follow-up MRI has been developed by the Consortium of Multiple Sclerosis Centres, acceptance and implementation in Canada have been suboptimal.
Methods
: To improve diagnosis, monitoring, and management of a clinically isolated syndrome and MS, a Canadian expert panel created consensus recommendations about the appropriate application of the 2010 McDonald criteria in routine practice, strategies to improve adherence to the standardized Consortium of Multiple Sclerosis Centres MRI protocol, and methods for ensuring effective communication among health care practitioners, in particular referring physicians, neurologists, and radiologists.
Results
: This article presents eight consensus statements developed by the expert panel, along with the rationale underlying the recommendations and commentaries on how to prioritize resource use within the Canadian healthcare system.
Conclusions
: The expert panel calls on neurologists and radiologists in Canada to incorporate the McDonald criteria, the Consortium of Multiple Sclerosis Centres MRI protocol, and other guidance given in this consensus presentation into their practices. By improving communication and general awareness of best practices for MRI use in MS diagnosis and monitoring, we can improve patient care across Canada by providing timely diagnosis, informed management decisions, and better continuity of care.
Recommandations du Groupe consultatif canadien sur l’utilisation de l’IRM pour le diagnostic et la surveillance de la SP.
Contexte:
Pour poser un diagnostic formel de sclérose en plaques (SP), par opposition à un syndrome isolé au point de vue clinique, une des deux conditions suivantes doit être remplie : une deuxième poussée clinique ou des constatations particulières à l’imagerie par résonance magnétique (IRM), selon les critères de McDonald. L’IRM est également importante après que le diagnostic ait été posé, comme moyen de surveiller l’activité subclinique de la maladie. Bien qu’un protocole standardisé pour le diagnostic et le suivi par l’IRM ait été développé par le Consortium of Multiple Sclerosis Centres, son acceptation et son application ont été sous-optimales au Canada.
Méthode:
Afin d’améliorer le diagnostic, la surveillance et la prise en charge d’un syndrome isolé au point de vue clinique et de la SP, un Groupe consultatif canadien d’experts a émis des recommandations consensus sur l’application appropriée des critères de McDonald (2010) en pratique clinique, des stratégies pour améliorer la fidélité au Consortium of Multiple Sclerosis Centres MRI protocol standardisé et des méthodes pour garantir la communication efficace entre les professionnels de la santé, particulièrement les médecins référents, les neurologues et les radiologistes.
Résultats:
Cet article présente huit énoncés de consensus développés par un groupe d’experts ainsi que le fondement de ces recommandations et des commentaires sur la façon de prioriser l’utilisation des ressources dans le cadre du système de santé canadien.
Conclusions:
Le groupe d’experts invite les neurologues et les radiologistes du Canada à incorporer dans leur pratique les critères de McDonald, le protocole d’IRM du Consortium of Multiple Sclerosis Centres ainsi que les autres directives émises dans le présent consensus. En améliorant la communication et en sensibilisant les professionnels de la santé au sujet de l’utilisation optimale de l’IRM pour le diagnostic et la surveillance de la SP, nous pouvons améliorer les soins aux patients à travers le Canada en établissant un diagnostic rapide, des décisions de traitement éclairées et une meilleure continuité dans les soins prodigués aux patients.
A follow-up study of patients with schizophrenia was conducted to examine change in striatal volumes and extrapyramidal symptoms after a change in medication.
Thirty-seven patients with schizophrenia ...and 23 healthy volunteers were examined. Patients at baseline receiving typical antipsychotics (N=10) or risperidone but exhibiting limited response (N=13) were switched to treatment with olanzapine. Patients receiving risperidone and exhibiting a good response (N=14) continued treatment with risperidone. Caudate, putamen, and pallidal volumes were assessed with magnetic resonance imaging. The Extrapyramidal Symptoms Rating Scale was used to assess clinical signs and symptoms.
At baseline, basal ganglia volumes in patients treated with typical antipsychotics were greater than in healthy subjects (putamen: 7.0% larger; globus pallidus: 20.7% larger). After the switch to olanzapine, putamen and globus pallidus volumes decreased (9.8% and 10.7%, respectively) and did not differ from those of healthy subjects at the follow-up evaluation. Akathisia was also reduced. In the patients receiving risperidone at baseline, basal ganglia volumes did not differ between those exhibiting good and poor response, and no significant volume changes were observed in subjects with poor risperidone response after the switch to olanzapine treatment.
Olanzapine reversed putamen and globus pallidus enlargement induced by typical antipsychotics but did not alter volumes in patients previously treated with risperidone. Changes in striatal volumes related to typical and atypical antipsychotics may represent an interactive effect between individual medications and unique patient characteristics.
The authors performed a longitudinal study of the effects on thalamic volume of switching from typical to atypical antipsychotic medications.
Magnetic resonance imaging scans were acquired from 10 ...subjects with chronic schizophrenia taking typical antipsychotics and 20 healthy volunteers. Subjects with schizophrenia were switched to olanzapine; both groups were rescanned.
At baseline, thalamic volumes in subjects with chronic schizophrenia were 5.8% greater than those of healthy volunteers. At follow-up, there was no significant difference between groups. Additional analysis revealed a significant positive correlation between baseline thalamic volume and dosage of typical antipsychotic medication. Higher dosages at baseline were correlated with larger reductions in volume after the switch to olanzapine.
Antipsychotic medication effects may be a factor in the wide range of thalamic volume differences reported between subjects with schizophrenia and healthy volunteers.
Socioeconomic status (SES) is often indicated as a factor that influences physical activity and associated health outcomes. This study examined the relationship between SES and sport participation, ...morphology, fitness and motor coordination in a sample of 1955 Flemish children 6-11 years of age. Gender, age and SES-specific values for morphologic dimensions, amount and type of sport participation and fitness and motor coordination tests were compared. SES was positively and significantly associated with sport participation and sports club membership in both sexes. Although differences were not consistently significant, morphologic dimensions and tests of fitness and motor coordination showed a trend in favor of children from higher SES. The results suggest that public and local authorities should consider providing equal opportunities for children in all social strata and especially those in the lower SES to experience the beneficial effects of sport participation through which they can enhance levels of physical fitness and motor coordination.
The purposes of this study were to assess the feasibility and safety of perfusion CT of patients with severe traumatic brain injury (TBI) at hospital admission and to examine whether early ...in-hospital mortality could be characterized with perfusion CT (PCT). The hypothesis was that PCT can be used to characterize brain death, when present, in patients with severe TBI at hospital admission.
In this prospective cohort pilot study, PCT was performed on patients with severe TBI at first imaging workup at hospital admission. PCT images were processed at the end of the study and assessed for features of brain death. The PCT features were then compared with the clinical outcome of in-hospital mortality.
A total of 19 patients (13 men 68.4%; six women 31.6%; mean age, 36.4 years; median, 27.5 years) had a mean hospital stay longer than 1 month. No complications of PCT were found. In the first 48 hours after admission, four patients (21%) died. Admission PCT changes suggesting brainstem death were sensitive (75%) and specific (100%) and had high positive (100%) and negative (93.75%) predictive value for correct classification early in-hospital mortality.
Admission PCT of patients with severe TBI was feasible and safe. Admission PCT findings helped in correctly classifying early in-hospital mortality in the first 48 hours of hospital admission.
We report a case of a patient who initially presented with a subarachnoid haemorrhage secondary to a ruptured supraclinoid internal carotid artery (ICA) blister aneurysm. The patient was treated ...successfully with a flow diverter stent (FD) and coiling; however, a large aneurysm recurrence via a feeding posterior communicating artery (PCOM) was noted on the 1-year follow-up angiogram. During the retreatment, a second FD in the ICA resulted in insufficient aneurysm stasis. Therefore, the decision was made to coil sacrifice the PCOM via posterior circulation access. During the first coil deployment, the distal coil end migrated through the mesh of two overlapping FD into the middle cerebral artery. This complication was a previously unrecognised possibility given the composition of the FD. This case report aims to discuss this process as a potential complication during neurointerventional procedures using these devices.
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