New nonsurgical therapies in the treatment of hepatocellular carcinoma.

The last decade has seen a rapid increase in the incidence of hepatocellular carcinoma in the United States, mostly because of the increased incidence of hepatitis C. Surgical therapy remains limited to the few patients who are surgical candidates at presentation. In addition, surgery has been plagued by high recurrence rates, which can reach 80% at 3 years. Systemic chemotherapy has been found to be ineffective, with response rates approaching 10% to 20%. Nonsurgical percutaneous therapies, including percutaneous locoregional ablative procedures (ethanol or acetic acid injection, radiofrequency ablation, microwave coagulation therapy, chemotherapy infusion, laser photocoagulation, and high-intensity ultrasound) and intra-arterial procedures (radioembolization with yttrium-90 microspheres or transcatheter intra-arterial chemoembolization) are gaining popularity because they are less invasive than surgery and can be nearly as effective in prolonging survival. Multiple studies have shown good response rates with high technical success rates, as well as significant survival advantages for nonresectable disease. Furthermore, they can be performed repeatedly without compromising liver function and at a considerably lower morbidity and cost than surgery.

MR imaging of the human brain at 1.5 T: regional variations in transverse relaxation rates in the cerebral cortex.

BACKGROUND AND PURPOSE: Heterogeneity in cortical signal intensity on T2-weighted MR images has been recently documented. Using a whole-brain, multiecho MR imaging technique, we sought to determine the T2 relaxation times of nine predefined regions in the cerebral cortex and one region in the deep gray matter. METHODS: Ten adult volunteers (nine men and one woman; age range, 18-40 y; average age, 30.8 y) underwent whole-brain imaging with an oblique coronal multiecho 3D Carr-Purcell-Meiboom-Gill MR sequence at 1000/25, 50, 75, 100, 125, and 150 (TR/TE). T2 measurements were obtained, with variably sized regions of interest, from the primary auditory cortex, primary visual cortex, caudate nucleus, superior frontal gyrus, inferior temporal gyrus, middle temporal gyrus, superior temporal gyrus, insula cortex, cingulate gyrus, and hippocampus. Repeated-measures analysis of variance was used to assess the existence of differences in T2 measurements among the anatomic locations. RESULTS: On the basis of T2 measurements, the gray matter structures examined could be divided into four statistically different groups. In ascending order of T2 measurements, the first group consisted of the primary auditory cortex and primary visual cortex; the second group, the caudate nucleus, superior frontal gyrus, inferior temporal gyrus, middle temporal gyrus, and superior temporal gyrus; the third group, the insula cortex; and the fourth group, the cingulate gyrus and hippocampus. CONCLUSION: Significant variation in T2 values among the cortical gray matter of the human brain exists.

Differences of renal parenchymal attenuation for acutely obstructed and unobstructed kidneys on unenhanced helical CT: a useful secondary sign?

OBJECTIVE: The purpose of this study was to ascertain whether the difference in attenuation frequently noted on unenhanced helical CT scans between a patient's acutely obstructed kidney and the unobstructed kidney is a reliable secondary sign of acute renal obstruction. CONCLUSION: In 95% of patients with acute renal obstruction, the affected kidney was less dense than the unobstructed kidney. When visually detected by radiologists using CT, this difference in density was at least two standard deviations above normal, making it a reliable secondary sign for acute obstruction.

X-linked adrenoleukodystrophy: the role of contrast-enhanced MR imaging in predicting disease progression.

BACKGROUND AND PURPOSE: Early assignment of disease progression among patients with X-linked adrenoleukodystrophy (ALD) is critical for the appropriate selection of effective therapy. We evaluated the association between contrast enhancement on T1-weighted spin-echo MR images and disease progression. METHODS: Clinical charts of patients with X-linked ALD were reviewed for age, availability of MR images of the brain, severity of neurologic impairment, and duration and number of follow-up evaluations. Forty-three male patients with X-linked ALD had undergone multiple MR imaging examinations of the brain that consisted of at least sagittal and axial T1-weighted spin-echo, axial double-echo spin-echo, and contrast-enhanced axial T1-weighted spin-echo imaging. The MR images were reviewed for the presence of contrast enhancement. In addition, global disease burden, as shown by the double-echo spin-echo images, was assessed using a visual scoring method (Loes score). RESULTS: Enhancement was seen on the initial T1-weighted spin-echo MR images of 21 (49%) patients; 18 (86%) of the 21 patients had disease progression revealed by the follow-up evaluations based on MR imaging (Loes) and neurologic scores. No enhancement was seen on the initial T1-weighted spin-echo MR images of 22 (51%) patients; for 18 (82%) of the 22 patients, no evidence of disease progression was revealed by the follow-up evaluations. CONCLUSION: There is a very strong association between the presence of contrast enhancement on T1-weighted MR images and X-linked ALD progression based on clinical evaluation and MR imaging.