Part 1: CAR Metabolic Dysfunction-Associated Steatotic Liver Disease Working Group Guidance Statements for Detecting and Grading Hepatic Steatosis Using Ultrasound, CT, or MRI.

The Canadian Association of Radiologists (CAR) metabolic dysfunction-associated steatotic liver disease (MASLD) Working Group (WG) is a multidisciplinary working group composed of radiologists, hepatologists, and family physicians. In this 3-part series, we provide Delphi consensus-based guidance on clinical and imaging findings for patients with known or suspected MASLD (formerly termed non-alcoholic fatty liver disease or NAFLD). Part 1 focuses on the detection and grading of hepatic steatosis on imaging; Part 2 on risk-stratification of patients with MASLD, including a patient pathway that incorporates serological and imaging investigations; and Part 3 on the implementation of practice recommendations for quality assurance using shear wave elastography (SWE) and magnetic resonance elastography (MRE) for disease staging. In the first part of these guidelines, we provide 17 guidance statements for detection, grading, and surveillance of hepatic steatosis using ultrasound (US), CT, or MRI. In addition to conventional B-mode US, we review current evidence on semi-quantitative and quantitative US techniques and provide guidance for appropriate indications and recommended technique.