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Total Brain Volume (total + brain_volume)
Selected AbstractsCaudate volume measurement in older adults with bipolar disorderINTERNATIONAL JOURNAL OF GERIATRIC PSYCHIATRY, Issue 2 2004John L. Beyer Abstract Background Decreased caudate volumes have been noted in unipolar depressed subjects, especially in the elderly and those with cognitive impairment. No differences have been noted in initial studies of multi-aged bipolar subjects; however, this region has not been examined in older bipolar subjects. Methods We examined the caudate nuclei volumes of 36 older bipolar subjects (mean age 58) and 35 older controls (mean age 62) using logistic regression analyses to control for age and gender differences. Differences between late- and early-onset (age-of-onset before age 45) bipolar subjects were also examined, as well as the effect of length of illness. Results The right caudate was noted to be smaller in older bipolar subjects compared with older controls when controlled for sex and age (p,=,0.0448). No differences were noted in overall brain volume nor lateral ventricular volume between the bipolar and control subjects. Late-onset bipolar subjects had a decrease in brain volume (p,=,0.035) compared with early-onset bipolar subjects. Late-onset bipolar subjects had a decrease in the right (p,=,0.044) and total (p,=,0.04) caudate size compared with older controls. Conclusions Right caudate volume is decreased in older bipolar subjects compared to controls. Bipolar subjects with late-onset illness have significantly decreased right and total caudate volumes compared to controls. This is affected by neither the length of illness nor the age of onset. Late-onset bipolar subjects have decreased total brain volume compared with early-onset bipolar subjects. Copyright © 2004 John Wiley & Sons, Ltd. [source] Automatic segmentation of the brain and intracranial cerebrospinal fluid in T1 -weighted volume MRI scans of the head, and its application to serial cerebral and intracranial volumetryMAGNETIC RESONANCE IN MEDICINE, Issue 5 2003Louis Lemieux A new fully automatic algorithm for the segmentation of the brain and total intracranial cerebrospinal fluid (CSF) from T1 -weighted volume MRI scans of the head, called Exbrain v.2, is described. The algorithm was developed in the context of serial intracranial volumetry. A brain mask obtained using a previous version of the algorithm forms the basis of the CSF segmentation. Improved brain segmentation is then obtained by iterative tracking of the brain,CSF interface. Gray matter (GM), white matter (WM), and intracranial CSF volumes and probability maps are calculated based on a model of intensity probability distribution (IPD) that includes two partial volume classes: GM-CSF and GM-WM. Accuracy was assessed using the Montreal Neurological Institute's (MNI) digital phantom scan. Reproducibility was assessed using scan pairs from 24 controls and 10 patients with epilepsy. Segmentation overlap with the gold standard was 98% for the brain and 95%, 96%, and 97% for the GM, WM, and total intracranial contents, respectively; CSF overlap was 86%. In the controls, the Bland and Altman coefficient of reliability (CR) was 35.2 cm3 for the total brain volume (TBV) and 29.0 cm3 for the intracranial volume (ICV). Scan-matching reduced CR to 25.2 cm3 and 17.1 cm3 for the TBV and ICV, respectively. For the patients, similar CR values were obtained for the ICV. Magn Reson Med 49:872,884, 2003. © 2003 Wiley-Liss, Inc. [source] Visceral fat is associated with lower brain volume in healthy middle-aged adultsANNALS OF NEUROLOGY, Issue 2 2010Stéphanie Debette MD Objective Midlife obesity has been associated with an increased risk of dementia. The underlying mechanisms are poorly understood. Our aim was to examine the cross-sectional association of body mass index (BMI), waist circumference (WC), waist-to-hip ratio (WHR), and computed tomography (CT)-based measurements of subcutaneous (SAT) and visceral (VAT) adipose tissue with various magnetic resonance imaging (MRI) markers of brain aging in middle-aged community adults. Methods Participants from the Framingham Offspring cohort were eligible if in addition to having measurements of BMI, WC, WHR, SAT, and VAT, they had undergone a volumetric brain MRI scan with measurements of total brain volume (TCBV), temporal horn volume (THV), white matter hyperintensity volume (WMHV), and MRI-defined brain infarcts (BI). All analyses were adjusted for age, sex, and time interval between abdominal CT and brain MRI. Results In a sample of 733 community participants (mean age, 60 years; 53% women), we observed an inverse association of BMI (estimate by standard deviation unit ± standard error = ,0.27 ± 0.12; p = 0.02), WC (,0.30 ± 0.12; p = 0.01), WHR (,0.37 ± 0.12; p = 0.02), SAT (,0.23 ± 0.11; p = 0.04), and VAT (,0.36 ± 0.12; p = 0.002) with TCBV, independent of vascular risk factors. The association between VAT and TCBV was the strongest and most robust, and was also independent of BMI (,0.35 ± 0.15; p = 0.02) and insulin resistance (,0.32 ± 0.13; p = 0.01). When adjusting for C-reactive protein levels, the associations were attenuated (,0.17 ± 0.13; p = 0.17 for VAT). No consistently significant association was observed between the anthropometric or CT-based abdominal fat measurements and THV, WMHV, or BI. Interpretation In middle-aged community participants, we observed a significant inverse association of anthropometric and CT-based measurements of abdominal, especially visceral, fat with total brain volume. ANN NEUROL 2010 [source] Rituximab in patients with primary progressive multiple sclerosis: Results of a randomized double-blind placebo-controlled multicenter trial,ANNALS OF NEUROLOGY, Issue 4 2009Kathleen Hawker MD Objective Rituximab, a monoclonal antibody selectively depleting CD20+ B cells, has demonstrated efficacy in reducing disease activity in relapsing-remitting multiple sclerosis (MS). We evaluated rituximab in adults with primary progressive MS (PPMS) through 96 weeks and safety through 122 weeks. Methods Using 2:1 randomization, 439 PPMS patients received two 1,000mg intravenous rituximab or placebo infusions every 24 weeks, through 96 weeks (4 courses). The primary endpoint was time to confirmed disease progression (CDP), a prespecified increase in Expanded Disability Status Scale sustained for 12 weeks. Secondary endpoints were change from baseline to week 96 in T2 lesion volume and total brain volume on magnetic resonance imaging scans. Results Differences in time to CDP between rituximab and placebo did not reach significance (96-week rates: 38.5% placebo, 30.2% rituximab; p = 0.14). From baseline to week 96, rituximab patients had less (p < 0.001) increase in T2 lesion volume; brain volume change was similar (p = 0.62) to placebo. Subgroup analysis showed time to CDP was delayed in rituximab-treated patients aged <51 years (hazard ratio [HR] = 0.52; p = 0.010), those with gadolinium-enhancing lesions (HR = 0.41; p = 0.007), and those aged <51 years with gadolinium-enhancing lesions (HR = 0.33; p = 0.009) compared with placebo. Adverse events were comparable between groups; 16.1% of rituximab and 13.6% of placebo patients reported serious events. Serious infections occurred in 4.5% of rituximab and <1.0% of placebo patients. Infusion-related events, predominantly mild to moderate, were more common with rituximab during the first course, and decreased to rates comparable to placebo on successive courses. Interpretation Although time to CDP between groups was not significant, overall subgroup analyses suggest selective B-cell depletion may affect disease progression in younger patients, particularly those with inflammatory lesions. Ann Neurol 2009;66:460,471 [source] Preliminary evidence for persistent abnormalities in amygdala volumes in adolescents and young adults with bipolar disorderBIPOLAR DISORDERS, Issue 6 2005Hilary P Blumberg Objectives:, Abnormalities in volumes of the amygdala have been reported previously in adolescents and adults with bipolar disorder (BD). Several studies have reported reduced volumes in adolescents with BD; however, both decreases and increases in volumes have been reported in adults with BD. Understanding of potential developmental contributions to these disturbances in morphology of the amygdala has been limited by the absence of longitudinal data in persons with BD. Here we use a within-subject longitudinal design to investigate whether amygdala volume abnormalities persist in adolescents and young adults with BD over a time interval of approximately 2 years. Methods:, Participants included 18 adolescents and young adults: 10 participants with BD I and 8 healthy comparison participants. Amygdala volumes were measured on high-resolution magnetic resonance imaging scans acquired twice for each subject over intervals of approximately 2 years. Amygdala volumes were the dependent measures in a mixed-model statistical analysis to compare amygdala volumes between groups over time while covarying for total brain volume. Results:, Amygdala volumes were significantly smaller in adolescents and young adults with BD compared with healthy participants (p = 0.018). The effect of time was not significant. Conclusions:, Although the sample size is modest, this study provides preliminary evidence to support the presence of decreased amygdala volumes in adolescents and young adults with BD that persist during this developmental epoch. [source] | ||||||||||