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Although functional MRI (fMRI) has shown to be a tool with great potential to study the normal and diseased human brain, the large variability in the detected hemodynamic responses across sessions and across subjects hinders a wider application. To investigate the long-term reproducibility of fMRI activation of verbal working memory (WM), eight normal(More)
PURPOSE To assess the reproducibility and accuracy compared to radiologists of three automated segmentation pipelines for quantitative magnetic resonance imaging (MRI) measurement of brain white matter signal abnormalities (WMSA). MATERIALS AND METHODS WMSA segmentation was performed on pairs of whole brain scans from 20 patients with multiple sclerosis(More)
OBJECTIVE To investigate the relationship between white matter abnormalities and impairment of gait and balance in older persons. METHODS Quantitative MRI was used to evaluate the brain tissue compartments of 28 older individuals separated into normal and impaired groups on the basis of mobility performance testing using the Short Physical Performance(More)
BACKGROUND Recent investigations using MRI suggest that older persons with mobility impairment have a greater volume of abnormal cerebral white matter compared with persons with normal mobility, thus raising the possibility that those with impairment have lesions in areas critical for the control of mobility. OBJECTIVE To utilize automated image analysis(More)
The relationship between performance on information processing efficiency measures and MRI-derived lesion volume including global and regional T2 and T1 lesion volumes was investigated in 20 patients with relapsing-remitting multiple sclerosis (RRMS) and secondary progressive multiple sclerosis (SPMS). Processing speed, as measured by the Sternberg Memory(More)
Changes in mean magnetic resonance imaging (MRI)-derived measurements between patient groups are often used to determine outcomes in therapeutic trials and other longitudinal studies of multiple sclerosis (MS). However, in day-to-day clinical practice the changes within individual patients may also be of interest In this paper, we estimated the measurement(More)
This article reports test-retest reproducibility of functional MRI (fMRI) measurement on brain activation elicited by auditory-cued sequential finger tapping. Eight right-handed volunteers participated in nine fMRI sessions, approximately eight weeks apart, for the duration of more than a year. The first scan session was repeated within a day to examine the(More)
White matter signal abnormality (WMSA) is often present in the MRIs of older persons with mobility impairment. We examined the relationship between impaired mobility and the progressive accrual of WMSA. Mobility was assessed with the Short Physical Performance Battery (SPPB) and quantitative measures of gait and balance. Fourteen subjects had baseline and(More)
T2 hypointensity (black T2, BT2) in the deep grey matter of multiple sclerosis (MS) patients correlate weakly with disability at 1.5 T. BT2 is likely to be caused by abnormal iron deposition. We compared the correlation between disability and deep grey matter BT2 measured on 3 T MRI and on 1.5 T MRI in 17 MS patients. We observed a significant correlation(More)
BACKGROUND AND PURPOSE Crossed cerebellar atrophy is uncommon in childhood arterial ischemic stroke. Acute corticospinal tract diffusion-weighted imaging (CST-DWI) changes occur in stroke of all ages. Contralateral CST-DWI is unexplained but approximates corticopontocerebellar pathways. We hypothesized that cerebellar atrophy can be quantified on clinical(More)