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Hepatic fibrosis is potentially reversible; however early diagnosis is necessary for treatment in order to halt progression to cirrhosis and development of complications including portal hypertension and hepatocellular carcinoma. Morphologic signs of cirrhosis on ultrasound (US), computed tomography (CT), and magnetic resonance imaging (MRI) alone are unreliable and are seen with more advanced disease. Newer imaging techniques to diagnose liver fibrosis are reliable and accurate, and include magnetic resonance elastography and US elastography (one-dimensional transient elastography and point shear wave elastography or acoustic radiation force impulse imaging). Research is ongoing with multiple other techniques for the noninvasive diagnosis of hepatic fibrosis, including MRI with diffusion-weighted imaging, hepatobiliary contrast enhancement, and perfusion; CT using perfusion, fractional extracellular space techniques, and dual-energy, contrast-enhanced US, texture analysis in multiple modalities, quantitative mapping, and direct molecular imaging probes. Efforts to advance the noninvasive imaging assessment of hepatic fibrosis will facilitate earlier diagnosis and improve patient monitoring with the goal of preventing the progression to cirrhosis and its complications.

Absolute official immunity blocks recovery of damages for constitutional violations committed by legislators, judges, prosecutors, and witnesses, no matter how egregious the violation. Under the Supreme Court's "functional approach," application of the doctrine does not turn on the officer's title, but on function. Social workers, parole boards and others enjoy official immunity when they engage in legislative, adjudicative, or prosecutorial functions. The policy underlying absolute immunity is that constitutional litigation will produce unacceptable social costs, mainly by discouraging officials from acting boldly and effectively in the public interest. This Article criticizes the Court's exclusive focus on function. While it may be necessary to sacrifice the vindication of constitutional rights and deterrence of violations in some circumstances, the function-based approach gives too much weight to the costs of constitutional remedies and pays too little attention to the vindication and deterrence benefits. Shifting from function to a more nuanced cost-benefit methodology would make good sense--and all the more so because the re-framing would support the recognition of multiple exceptions to present-day absolute-immunity rules, thus better serving the overarching remedial goals of constitutional tort law. [ABSTRACT FROM AUTHOR]

Rocks may undergo complex pressure-temperature (P-T) histories during orogenesis in response to alternating episodes of synconvergent burial and exhumation. In this study, chemical zoning in garnets combined with textural and chemical evidence from the schist of Willow Creek in the Albion Mountains of south-central Idaho (USA), reveals a complex P-T path during the early stages of Sevier orogenesis. The distribution of quartz inclusions combined with internal resorption features establishes a hiatus in garnet growth. Chemical zoning was simulated using a G-minimization approach to yield a P-T path consisting of three distinct pressure changes during increasing temperature, defining an 'N' shape. Lu-Hf isochron ages from multiple garnet fractions and whole-rock analyses in two samples are 132.1 ± 2.4 and 138.7 ± 3.5 Ma. The samples were collected from the hanging wall of the Basin-Elba thrust fault and yielded results similar to those previously obtained from the footwall. This leads to several conclusions: (1) Both the hanging wall and footwall experienced the same metamorphic event, (2) the paths document a previously unrecognized crustal thickening and synorogenic extension cycle that fills an important time gap in the shortening history of the Sevier retroarc, suggesting progressive eastward growth of the orogen rather than a two-stage history, and (3) episodes of extensional exhumation during protracted convergent orogenesis are increasingly well recognized and highlight the dynamic behavior of orogenic belts. Electronic supplementary material The online version of this article (doi:10.1007/s00410-015-1171-2) contains supplementary material, which is available to authorized users., Author(s): Eric D. Kelly[sup.1] , Thomas D. Hoisch[sup.2] , Michael L. Wells[sup.3] , Jeffrey D. Vervoort[sup.4] , Mengesha A. Beyene[sup.5] Author Affiliations: (1) Department of Geological Sciences, University of Texas, [...]

Background: Dual-energy virtual monoenergetic images can increase iodine signal, potentially increasing the conspicuity of hepatic masses. Purpose: To determine if dual-energy 50-keV virtual monoenergetic images improve visualization of key imaging findings or diagnostic confidence for small (≤2 cm) hepatocellular carcinomas (HCC) at multiphase, contrast-enhanced liver computed tomography (CT). Material and Methods: Patients with chronic liver disease underwent multiphase dual-energy CT imaging for HCC, with late arterial and delayed phase dual-energy 50-keV images reconstructed. Two non-reader subspecialized gastrointestinal (GI) radiologists established the reference standard, determining the location and diagnosis of all hepatic lesions using predetermined criteria. Three GI radiologists interpreted mixed kV CT images without or with dual-energy 50-keV images. Radiologists identified potential HCCs and rated their confidence (0–100 scales) in imaging findings of arterial enhancement, enhancing capsule, tumor washout, and LI-RADS 5 (2018) category. Results: In total, 45 patients (14 women; mean age = 59.5 ± 10.9 years) with chronic liver disease were included. Of them, 19 patients had 25 HCCs ≤2 cm (mean size = 1.5 ± 0.4 cm). There were 17 LI-RADS 3 and 4 lesions and 19 benign lesions. Reader confidence in imaging findings of arterial enhancement, enhancing capsule, and non-peripheral washout significantly increased with dual-energy images (P ≤ 0.022). Overall confidence in HCC diagnosis increased significantly with dual-energy 50-keV images (52.4 vs. 68.8; P = 0.001). Dual-energy images demonstrated a slight but significant decrease in overall image quality. Conclusion: Radiologist confidence in key imaging features of small HCCs and confidence in imaging diagnosis increases with use of dual-energy 50-keV images at multiphase, contrast-enhanced liver CT. [ABSTRACT FROM AUTHOR]