Cesarean delivery is a commonly performed operation and accounts for nearly one-third of all births in the United States. Although it is a safe procedure, cesarean delivery has a variety of acute and chronic complications that prompt imaging with ultrasonography (US), computed tomography, and magnetic resonance imaging. Acute complications include hematomas in specific locations that are unique to the procedure, as well as a variety of infections. A bladder flap hematoma occurs in the space between the bladder and the lower uterine segment, whereas a subfascial hematoma is an extraperitoneal collection located in the prevesical space posterior to the rectus muscles and anterior to the peritoneum. Puerperal infections after cesarean delivery include abscesses, wound infections and dehiscence, uterine dehiscence and rupture, and pelvic thrombophlebitis. The prevalence of chronic complications related to the healed cesarean delivery scar is unknown, but the scar may result in technical limitations for pelvic US due to the adhesions between the anterior lower uterine segment and the anterior abdominal wall. The cesarean delivery scar also leaves the patient susceptible to several unique diagnoses. A cesarean scar "niche" is a tethering of the endometrium that can serve as a reservoir for intermenstrual blood and fluid. Intrauterine devices can be malpositioned in the cesarean delivery scar, and endometrial implants can develop in the abdominal wall years after surgery. These patients are also at increased risk for implantation abnormalities including cesarean scar ectopic pregnancy, retained products of conception, and placenta accreta. Familiarity with the normal postoperative findings following cesarean delivery is necessary to recognize acute and chronic complications, which are being encountered with increasing frequency.
The Liver Imaging Reporting and Data System (LI-RADS®) is a comprehensive system for standardizing the terminology, technique, interpretation, reporting, and data collection of liver observations in individuals at high risk for hepatocellular carcinoma (HCC). LI-RADS is supported and endorsed by the American College of Radiology (ACR). Upon its initial release in 2011, LI-RADS applied only to liver observations identified at CT or MRI. It has since been refined and expanded over multiple updates to now also address ultrasound-based surveillance, contrast-enhanced ultrasound for HCC diagnosis, and CT/MRI for assessing treatment response after locoregional therapy. The LI-RADS 2018 version was integrated into the HCC diagnosis, staging, and management practice guidance of the American Association for the Study of Liver Diseases (AASLD). This article reviews the major LI-RADS updates since its 2011 inception and provides an overview of the currently published LI-RADS algorithms.
The US Liver Imaging Reporting and Data System (LI-RADS) was released in 2017 and is the newest of the four American College of Radiology (ACR) LI-RADS algorithms. US LI-RADS provides standardized terminology, technical recommendations, and a reporting framework for US examinations performed for screening or surveillance in patients at risk for developing hepatocellular carcinoma (HCC). The appropriate patient population for screening and surveillance includes individuals who are at risk for developing HCC but do not have known or suspected cancer. This includes patients with cirrhosis from any cause and subsets of patients with chronic hepatitis B virus infection in the absence of cirrhosis. In an HCC screening or surveillance study, US LI-RADS recommends assigning two scores that apply to the entire study: the US category, which determines follow-up, and a visualization score, which communicates the expected level of sensitivity of the examination but does not affect management. Three US categories are possible: US-1 negative, a study with no evidence of HCC; US-2 subthreshold, a study in which an observation less than 10 mm is depicted that is not definitely benign; and US-3 positive, a study in which an observation greater than or equal to 10 mm or a new thrombus in vein is identified, for which diagnostic contrastmaterial-enhanced imaging is recommended. Three visualization scores are possible: A (no or minimal limitations), B (moderate limitations), and C (severe limitations).
Since being introduced more than 30 years ago, endovaginal ultrasonography (US) and quantitative testing of serum levels of the beta subunit of human chorionic gonadotropin have become the standard means of establishing the presence of normal intrauterine pregnancy (IUP), failed IUP, and ectopic pregnancy. Appropriate use of these powerful tools requires clear, standardized interpretations based on conservative criteria to protect both the pregnancy and the mother. Since diagnoses are assigned earlier and available medical treatments for ectopic pregnancy and failed IUP are expanding, emphasis must carefully shift toward watchful waiting when the mother is clinically stable and a definitive location for the pregnancy cannot be established with US. To this end and to prevent inadvertent harm to early normal pregnancies, the Society of Radiologists in Ultrasound convened a consensus panel of radiologists, obstetricians, and emergency medicine physicians in 2012 with the goal of reviewing current literature and clinical practices and formulating modern criteria and terminology for the various first-trimester outcomes.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.
hi@scite.ai
10624 S. Eastern Ave., Ste. A-614
Henderson, NV 89052, USA
Copyright © 2024 scite LLC. All rights reserved.
Made with 💙 for researchers
Part of the Research Solutions Family.