Axial Magnetic Resonance Imaging Slices Research Articles

Magnetic resonance imaging analysis of amygdala and other subcortical brain regions in adolescents with bipolar disorder.

Few studies have examined the abnormalities that underlie the neuroanatomy of bipolar disorder in youth. The aim of this study was to evaluate brain regions that are thought to modulate mood utilizing quantitative analyses of thin-slice magnetic resonance imaging (MRI) scans of adolescents with bipolar disorder. We hypothesized that adolescents with bipolar disorder would exhibit abnormalities in brain regions that are involved in the regulation of mood including the amygdala, globus pallidus, caudate, putamen, and thalamus. Bipolar adolescents (n = 23) and healthy subjects (n = 20) matched for age, race, sex, socioeconomic status, IQ, education and Tanner stage, were evaluated using the Washington University at St Louis Kiddie-Schedule for Affective Disorders and Schizophrenia (WASH-U K-SADS). Contiguous 1 mm axial T1-weighted MRI slices were obtained using a GE 1.5 T MR scanner. Regions of interest (ROI) included total cerebral volume, amygdala, globus pallidus, caudate, putamen, and thalamus. Total cerebral volume was smaller in bipolar adolescents than in healthy adolescents. A MANCOVA revealed a significant group difference in overall ROI volumes after adjusting for total cerebral volume. Specifically, adolescents with bipolar disorder exhibited smaller amygdala and enlarged putamen compared with healthy subjects. Our findings indicate that adolescents with bipolar disorder exhibit abnormalities in some of the brain regions that are thought to be involved in the regulation of mood. Additional structural and functional neuroimaging investigations of children, adolescents, and adults with bipolar disorder are necessary to clarify the role of these brain regions in the neurophysiology of adolescent bipolar disorder.

Prediction of total subcutaneous abdominal, intraperitoneal, and retroperitoneal adipose tissue masses in men by a single axial magnetic resonance imaging slice

To develop a simplified but accurate method for determining the masses of various abdominal adipose tissue compartments, we studied the predictive value of masses of intraperitoneal, retroperitoneal, and subcutaneous abdominal adipose tissue determined on single axial abdominal magnetic resonance imaging (MRI) slices taken at various intervertebral levels from the 12th thoracic to 1st sacral vertebra (identified on a sagittal section) for the respective total masses of each compartment calculated from contiguous 10-mm thick MRI slices covering the entire abdomen in 49 men (26 without diabetes and 23 with non-insulin-dependent diabetes mellitus). The MRI slice at the intervertebral level between the lumbar (L) 2 and 3 vertebrae showed the highest and most consistent predictive value for all three compartments (R2 = 0.85 for all). Furthermore, compared with other intervertebral levels, the L2-L3 level had a higher amount of intraperitoneal and retroperitoneal adipose tissue mass. We conclude that determining the masses of various abdominal adipose tissue compartments at the L2-L3 intervertebral level by MRI is an acceptably reliable and accurate method for studying abdominal adiposity in men.

Longitudinal Changes in Magnetic Resonance Imaging Brain Volumes in Abstinent and Relapsed Alcoholics

Chronic alcoholism is associated with smaller volumes of cortical gray matter and white matter and a complementary increase in brain cerebrospinal fluid (CSF) volumes, relative to age norms. This longitudinal study quantified the extent of brain volume changes associated with abstinence and drinking at three time points in chronic alcoholics. We obtained magnetic resonance imaging (MRI) on 58 alcoholic men after an average of 12 days (MRI-1) and 32 days (MRI-2) of sobriety. In addition, 58 healthy control subjects were scanned at a comparable interval. At MRI-3, 11 controls and 39 alcoholics were rescanned, 2-12 months after MRI-2; 19 alcoholics had abstained, and 20 had resumed drinking. Axial MRI slices were segmented into cortical gray matter, white matter, and CSF and summed over seven slices; lateral and third ventricular volumes were also estimated. MRI volume changes were corrected using an estimate of interscan measurement error caused by head positioning differences, and then divided by the interval to yield rates of change (slopes). From MRI-1 to MRI-2, the alcoholic group showed declines in CSF volumes of the lateral ventricles and posterior cortical sulci, and a trend toward an increase in anterior cortical gray matter volume relative to the control group. From MRI-2 to MRI-3, third ventricular volumes decreased in the abstainers relative to the relapsers and controls; cortical white matter volume decreased in the relapsers. In the relapsers, lifetime consumption of alcohol (as of MRI-1) predicted later vulnerability to white matter volume decline and third ventricular enlargement with resumption of drinking. These data suggest that improvement in cortical gray matter, sulcal, and lateral ventricular volumes occur early in the course of abstinence, and that improvement in third ventricular volume appears later with continued abstinence.(ABSTRACT TRUNCATED AT 250 WORDS)