Ultrasound Liver Fat Quantification on Pediatric Patients

Inclusion Criteria: * Subjects at age of 6-18 years old (≥6 \& \<18) who are able to provide assent to participate and have a parent/legal guardian who is able to provide informed consent for the subject to participate. * Subject must be eligible for a standard abdominal ultrasound examination and standard non-contrast MRI examination. * In addition, at least one of the following criteria must also be met: * Overweight or obese (BMI-for-age ≥ 85th percentile). * Diagnosed with Type II diabetes per standard clinical guidelines. * Diagnosed with hypercholesterolemia per standard clinical guidelines. * Diagnosed with or clinically suspected of having NAFLD/NASH based on previous medical record, medical imaging, liver biopsy, and/or laboratory testing. Exclusion Criteria: * Evidence of hepatotoxicity in the clinical judgment of the investigator. * History of chronic liver disease (e.g., viral hepatitis, cholestatic hepatitis, or autoimmune liver disease). * Use of drugs associated with hepatic steatosis1: amiodarone, aethotrexate, nucleoside reverse transcriptase inhibitors (didanosine, stavudine), valproic acid, dexamethasone, tamoxifen, 5-FU-based adjuvant chemotherapy, apo-B inhibitors (mipomersen, lomitapide), tetracycline exceeding 2 g/day and acetylsalicylic acid exceeding 150 mg/kg. Note: patients taking tetracycline (≤ 2 g/day), acetylsalicylic acid (≤150 mg/kg) are allowed to be enrolled. * Subjects with hepatic lesions that cannot be excluded from the imaging field during ultrasound LFQ data acquisition. * Subjects anticipated or planned to undergo any therapeutic intervention during enrollment period that, at discretion of the Investigator, may affect liver fat content (e.g., bariatric surgery, chemotherapy). * History of previous liver surgery or hepatic implants that, at the discretion of the Investigator, may adversely impact ultrasound or MRI image quality or the subject's eligibility to undergo ultrasound or MRI. * Subjects with unstable clinical status, late stages of a given disease, or unpredictable clinical course of a given disease. * Subjects with evidence of COVID-19 or with the substantial risk of COVID-19 infection.