Sixteen patients with cirrhosis of the liver underwent cranial magnetic resonance (MR) imaging and transarterial portography to evaluate the relationship between basal ganglia lesions and portal-systemic collateral vessels. No neuropsychiatric disturbance was observed in any of the patients at the time of the MR examination, but four patients with portal-systemic encephalopathy were included in the study. Basal ganglia lesions, characterized by increased signal intensity on T1-weighted MR images, were observed in nine of the 16 patients, including the four with portal-systemic encephalopathy. These nine patients had large portal-systemic collateral vessels that were more than 10 mm in diameter. These collateral vessels were receiving blood from the superior mesenteric vein (SMV) in all nine patients. The lesions involved the globus pallidus and portions of internal capsules in a bilateral and symmetric fashion and did not exhibit mass effect. The authors conclude that there may be a significant relationship between high-intensity basal ganglia lesions and large portal-systemic collateral vessels receiving blood from the SMV.

To study the morphology of the normal and inflamed bladder wall, the findings of magnetic resonance imaging and histopathologic examination of 13 in vitro specimens were correlated. Normal bladder wall appeared as a band of intermediate signal intensity on T1-weighted images and as bands of low (inner) and intermediate (outer) signal intensity on T2-weighted images. Inflamed bladder walls demonstrated two additional inner bands of intermediate (inner) and high (innermost) signal intensity on T1-weighted images and high (inner) and low (innermost) signal intensity on T2-weighted images. The mean histopathologic percentages of muscle bundles in inner and outer bands that appeared on T2-weighted images were 92.5% +/- 4.9 and 78.3% +/- 8.2, respectively. The authors conclude that the total thickness of the two bands of differing intensity that appeared on the T2-weighted images of the normal bladder wall correlated well morphometrically with the muscle layers in the histopathologic specimens, and that the different signal intensities in the muscle layer represent a compact inner and looser outer arrangement of smooth muscle bundles.

No abstract

To clarify the importance of imaging plane in evaluation of invasion by tumor into muscle, 50 patients with bladder tumors underwent examination with magnetic resonance (MR) imaging performed with an oblique plane and the early phase of contrast enhancement. After the ideal oblique plane was selected, an oblique T2-weighted image was obtained. Gadopentetate dimeglumine was then administered, and an oblique T1-weighted image was obtained. The staging based on oblique T2-weighted and oblique contrast material-enhanced T1-weighted MR images was then correlated with histopathologic staging. The respective accuracies of oblique contrast-enhanced T1-weighted and oblique T2-weighted images were 78% and 60% for overall staging (P < .05), 90% and 74% for differentiation between (a) stage T1 and lower-stage tumors and (b) stage T2 and higher-stage tumors (P < .05), and 92% and 88% for differentiation between (a) stage T2 and lower-stage tumors and (b) stage T3a and higher-stage tumors (P > .05). Oblique MR imaging performed in conjunction with the early phase of contrast enhancement showed significantly high staging accuracy, especially in differentiation between superficial tumors and tumors with superficial muscle invasion.

3D reconstruction imaging is superior to conventional 2D CT in assessment of pleural invasion by peripheral bronchogenic carcinoma.