Gadolinium-enhanced TurboFLASH imaging is a valuable method in the examination of breast lesions suspected of being malignant.

No abstract

Near infrared spectroscopy (NIRS) and functional magnetic resonance imaging (fMRI) both allow non-invasive monitoring of cerebral cortical oxygenation responses to various stimuli. To compare these methods in elderly subjects and to determine the effect of age on cortical oxygenation responses, we determined motor-task-related changes in deoxyhemoglobin concentration ([HHb]) over the left motor cortex in six healthy young subjects (age 35 +/- 9 years, mean +/- SD) and five healthy elderly subjects (age 73 +/- 3 years) by NIRS and blood-oxygen-level-dependent (BOLD) fMRI simultaneously. The motor-task consisted of seven cycles of 20-sec periods of contralateral finger-tapping at a rate as fast as possible alternated with 40-sec periods of rest. Time-locked averages over the seven cycles were used for further analysis. Task-related decreases in [HHb] over the motor cortex were measured by NIRS, with maximum changes of -0.83 +/- 0.38 mumol/L (P < 0.01) for the young and -0.32 +/- 0.17 mumol/L (P < 0.05) for the elderly subjects. The BOLD-fMRI signal increased over the cortex volume under investigation with NIRS, with maximum changes of 2.11 +/- 0.72% (P < 0.01) for the young and 1.75 +/- 0.71% (P < 0.01) for the elderly subjects. NIRS and BOLD-fMRI measurements showed good correlation in the young (r = -0.70, r(2) = 0.48, P < 0.001) and elderly subjects (r = -0.82, r(2) = 0.67, P < 0.001). Additionally, NIRS measurements demonstrated age-dependent decreases in task-related cerebral oxygenation responses (P < 0.05), whereas fMRI measurements demonstrated smaller areas of cortical activation in the elderly subjects (P < 0.05). These findings demonstrate that NIRS and fMRI similarly assess cortical oxygenation changes in young subjects and also in elderly subjects. In addition, cortical oxygenation responses to brain activation alter with aging.

Near infrared spectroscopy (NIRS) and functional magnetic resonance imaging (fMRI) both allow non-invasive monitoring of cerebral cortical oxygenation responses to various stimuli. To compare these methods in elderly subjects and to determine the effect of age on cortical oxygenation responses, we determined motor-task-related changes in deoxyhemoglobin concentration ([HHb]) over the left motor cortex in six healthy young subjects (age 35 +/- 9 years, mean +/- SD) and five healthy elderly subjects (age 73 +/- 3 years) by NIRS and blood-oxygen-level-dependent (BOLD) fMRI simultaneously. The motor-task consisted of seven cycles of 20-sec periods of contralateral finger-tapping at a rate as fast as possible alternated with 40-sec periods of rest. Time-locked averages over the seven cycles were used for further analysis. Task-related decreases in [HHb] over the motor cortex were measured by NIRS, with maximum changes of -0.83 +/- 0.38 mumol/L (P < 0.01) for the young and -0.32 +/- 0.17 mumol/L (P < 0.05) for the elderly subjects. The BOLD-fMRI signal increased over the cortex volume under investigation with NIRS, with maximum changes of 2.11 +/- 0.72% (P < 0.01) for the young and 1.75 +/- 0.71% (P < 0.01) for the elderly subjects. NIRS and BOLD-fMRI measurements showed good correlation in the young (r = -0.70, r(2) = 0.48, P < 0.001) and elderly subjects (r = -0.82, r(2) = 0.67, P < 0.001). Additionally, NIRS measurements demonstrated age-dependent decreases in task-related cerebral oxygenation responses (P < 0.05), whereas fMRI measurements demonstrated smaller areas of cortical activation in the elderly subjects (P < 0.05). These findings demonstrate that NIRS and fMRI similarly assess cortical oxygenation changes in young subjects and also in elderly subjects. In addition, cortical oxygenation responses to brain activation alter with aging.

The susceptibility to glucocorticoid-induced bone loss may vary in different parts of the skeleton. We studied 62 patients with rheumatoid arthritis, 26 of whom were on low-dose glucocorticoid treatment. Bone mineral content (BMC) in the forearm was measured by single photon absorptiometry at a cortical, diaphyseal, and at a mixed cortical and trabecular, metaphyseal site. Lumbar BMC was measured by dual energy computed tomography in a trabecular and a cortical region of interest. The presence of vertebral deformities was evaluated on lateral spine radiographs. After correction for possibly confounding variables, prednisone therapy significantly influenced BMC at both the trabecular (-22.0%, 95% confidence interval -36.0% to -8.1%) and cortical (-24.8%, 95% confidence interval -39.3% to -10.3%) lumbar site. A significant effect was also seen at the metaphyseal (-15.7%, 95% confidence interval -27.1% to -4.2%), but not the diaphyseal (-3.9%, 95% confidence interval -14.1% to 6.4%) site in the forearm. Correlations between peripheral and vertebral BMC were moderate at best. The diaphyseal to metaphyseal BMC ratio did not identify patients with vertebral osteoporosis. It is concluded that the anterior cortical rim of the vertebral body is more susceptible to the effects of glucocorticoids than the cortical bone in the forearm, and that measurements of trabecular and anterior cortical vertebral BMC are essential in the management of patients with possible glucocorticoid-associated osteoporosis.