A Multicenter Assessment of Interreader Reliability of LI-RADS Version 2018 for MRI and CT.

Background Various limitations have impacted research evaluating reader agreement for Liver Imaging Reporting and Data System (LI-RADS). Purpose To assess reader agreement of LI-RADS in an international multicenter multireader setting using scrollable images. Materials and Methods This retrospective study used deidentified clinical multiphase CT and MRI and reports with at least one untreated observation from six institutions and three countries; only qualifying examinations were submitted. Examination dates were October 2017 to August 2018 at the coordinating center. One untreated observation per examination was randomly selected using observation identifiers, and its clinically assigned features were extracted from the report. The corresponding LI-RADS version 2018 category was computed as a rescored clinical read. Each examination was randomly assigned to two of 43 research readers who independently scored the observation. Agreement for an ordinal modified four-category LI-RADS scale (LR-1, definitely benign; LR-2, probably benign; LR-3, intermediate probability of malignancy; LR-4, probably hepatocellular carcinoma [HCC]; LR-5, definitely HCC; LR-M, probably malignant but not HCC specific; and LR-TIV, tumor in vein) was computed using intraclass correlation coefficients (ICCs). Agreement was also computed for dichotomized malignancy (LR-4, LR-5, LR-M, and LR-TIV), LR-5, and LR-M. Agreement was compared between research-versus-research reads and research-versus-clinical reads. Results The study population consisted of 484 patients (mean age, 62 years ± 10 [SD]; 156 women; 93 CT examinations, 391 MRI examinations). ICCs for ordinal LI-RADS, dichotomized malignancy, LR-5, and LR-M were 0.68 (95% CI: 0.61, 0.73), 0.63 (95% CI: 0.55, 0.70), 0.58 (95% CI: 0.50, 0.66), and 0.46 (95% CI: 0.31, 0.61) respectively. Research-versus-research reader agreement was higher than research-versus-clinical agreement for modified four-category LI-RADS (ICC, 0.68 vs 0.62, respectively; P = .03) and for dichotomized malignancy (ICC, 0.63 vs 0.53, respectively; P = .005), but not for LR-5 (P = .14) or LR-M (P = .94). Conclusion There was moderate agreement for LI-RADS version 2018 overall. For some comparisons, research-versus-research reader agreement was higher than research-versus-clinical reader agreement, indicating differences between the clinical and research environments that warrant further study. © RSNA, 2023 Supplemental material is available for this article. See also the editorials by Johnson and Galgano and Smith in this issue.

Life Cycle Greenhouse Gas Impacts of Coal and Imported Gas-Based Power Generation in the Indian Context.

Few studies have evaluated the life cycle greenhouse gas (GHG) impacts associated with India's power sector, despite the expectation that it will dominate new thermal generation capacity additions over the coming decades. Here, we utilize India-specific supply chain data to estimate life cycle GHG emissions associated with power generated by combustion of Indian coal and liquefied natural gas (LNG) imported from the United States. Life cycle impacts of domestic coal power vary widely (80% confidence interval (CI): 951-1231 kg CO2eq/MWh) because of heterogeneity in existing power plant characteristics such as efficiency, age, and capacity. Less variability is observed for LNG sourced from northeast United States and used in the existing Indian combined cycle gas turbine (CCGT) fleet (80% CI: 523-648 kg CO2eq/MWh). On average, life cycle GHG emissions from LNG imported into India are ∼54% lower than those associated with Indian coal. However, the GHG intensity of the Indian coal-power sector may be reduced by 13% by retiring plants with the lowest efficiencies and replacing them with higher-efficiency supercritical plants. Improvement of the CCGT fleet efficiency from its current level (41%) to that of a new plant with an F-class turbine (50%) could reduce life cycle GHG emissions for LNG-sourced power by 19%.

LI-RADS technical requirements for CT, MRI, and contrast-enhanced ultrasound.

Accurate detection and characterization of liver observations to enable HCC diagnosis and staging using LI-RADS requires a technically adequate imaging exam. To help achieve this objective, LI-RADS has proposed technical requirements for CT, MR, and contrast-enhanced ultrasound of liver. This article reviews the technical requirements for liver imaging, including the description of minimum acceptable technical standards, such as the scanner hardware requirements, recommended dynamic imaging phases, and common technical challenges of liver imaging.

Cholangiocarcinoma: classification, diagnosis, staging, imaging features, and management.

Cholangiocarcinoma is a relatively uncommon malignant neoplasm with poor prognosis. The distinction between extrahepatic and intrahepatic subtypes is important as epidemiological features, biologic and pathologic characteristics, and clinical course are different for both entities. This review study focuses on the role imaging plays in the diagnosis, classification, staging, and post-treatment assessment of cholangiocarcinoma.

Imaging of the small intestine in Crohn's disease: Joint position statement of the Indian Society of Gastroenterology and Indian Radiological and Imaging Association.

The Indian Society of Gastroenterology (ISG) Task Force on Inflammatory Bowel Disease and the Indian Radiological and Imaging Association (IRIA) developed combined ISG-IRIA evidence-based best-practice guidelines for imaging of the small intestine in patients with suspected or known Crohn's disease. These 29 position statements, developed through a modified Delphi process, are intended to serve as reference for teaching, clinical practice, and research.

Clinical utility of BOLD fMRI in preoperative work-up of epilepsy.

Surgical techniques have emerged as a viable therapeutic option in patients with drug refractory epilepsy. Pre-surgical evaluation of epilepsy requires a comprehensive, multiparametric, and multimodal approach for precise localization of the epileptogenic focus. Various non-invasive techniques are available at the disposal of the treating physician to detect the epileptogenic focus, which include electroencephalography (EEG), video-EEG, magnetic resonance imaging (MRI), functional MRI including blood oxygen level dependent (BOLD) techniques, single photon emission tomography (SPECT), and (18)F-fluorodeoxyglucose (FDG) positron emission tomography (PET). Currently, non-invasive high-resolution MR imaging techniques play pivotal roles in the preoperative detection of the seizure focus, and represent the foundation for successful epilepsy surgery. BOLD functional magnetic resonance imaging (fMRI) maps allow for precise localization of the eloquent cortex in relation to the seizure focus. This review article focuses on the clinical utility of BOLD (fMRI) in the pre-surgical work-up of epilepsy patients.

Amphicrine carcinoma of the liver.

Amphicrine tumors are defined by evidence of both glandular and neuroendocrine differentiation in the same cell. These are extremely rare tumors, with only scattered case reports in the pancreas and stomach. We here report a case of amphicrine carcinoma occurring in apparent isolation in the liver. The tumor was characterized by signet ring cell morphology, mucicarmine, and periodic acid Schiff with diastase (PASD) positivity, and expression of chromogranin, synaptophysin, villin, and CDX2. No other tumor was identified by radiological or endoscopic examination of the gastrointestinal tract. The patient is disease-free 22 months after the resection. We speculate that this represents the first reported occurrence of primary amphicrine carcinoma of the liver.

MR imaging of liver fibrosis: current state of the art.

Chronic liver disease is a major public health problem worldwide. Liver fibrosis, a common feature of almost all causes of chronic liver disease, involves the accumulation of collagen, proteoglycans, and other macromolecules within the extracellular matrix. Fibrosis tends to progress, leading to hepatic dysfunction, portal hypertension, and ultimately cirrhosis. Liver biopsy, the standard of reference for diagnosing liver fibrosis, is invasive, costly, and subject to complications and sampling variability. These limitations make it unsuitable for diagnosis and longitudinal monitoring in the general population. Thus, development of a noninvasive, accurate, and reproducible test for diagnosis and monitoring of liver fibrosis would be of great value. Conventional cross-sectional imaging techniques have limited capability to demonstrate liver fibrosis. In clinical practice, imaging studies are usually reserved for evaluation of the presence of portal hypertension or hepatocellular carcinoma in cases that have progressed to cirrhosis. In response to the rising prevalence of chronic liver diseases in Western nations, a number of imaging-based methods including ultrasonography-based transient elastography, computed tomography-based texture analysis, and diverse magnetic resonance (MR) imaging-based techniques have been proposed for noninvasive diagnosis and grading of hepatic fibrosis across its entire spectrum of severity. State-of-the-art MR imaging-based techniques in current practice and in development for noninvasive assessment of liver fibrosis include conventional contrast material-enhanced MR imaging, double contrast-enhanced MR imaging, MR elastography, diffusion-weighted imaging, and MR perfusion imaging.

Ultrasound of adnexal masses.

Current advancements in imaging technology, especially three-dimensional/four-dimensional ultrasound and contrast-enhanced imaging, have increased the diagnostic yield of adnexal masses. The benefit of ultrasound is the characterization of an adnexal mass, suggesting the probable etiology of the mass. Masses may be divided as solid, cystic, or complex. It is predominantly the solid and complex masses that need a thorough evaluation. The role of color-flow imaging is now gaining importance and criteria for distinguishing between benign and malignant masses are often possible. Availability of a scoring system enables the differentiation of small adnexal masses. Several benign lesions may present as complex masses but can be distinguished and diagnosed on sonography. The availability of 3D ultrasound has been of great use to understand spatial relations and vascular morphology. Sonography allows a more detailed assessment of morphologic features of an adnexal mass. With a benign-appearing adnexal mass on sonography, the need for any further diagnostic tests is often obviated.

Non-infantile variant of desmoplastic ganglioglioma: a report of 2 cases.

Desmoplastic infantile gangliogliomas (DIGs) are uncommon supratentorial brain tumors with a usually good prognosis despite an aggressive radiological appearance. These tumors form part of a spectrum of desmoplastic infantile tumors that includes desmoplastic infantile astrocytomas. DIGs are classified as benign WHO grade I tumors of infancy. Non-infantile variants of this biologically benign intracranial neoplasm are rare, with only four previous case reports in the literature. We report two cases of non-infantile DIG diagnosed at our institution on the basis of clinical features, radiological appearance and histological findings.