Study guide
13.2 Diffuse Liver Disease
ARRT Sonography Primary
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1 Introduction & Exam Overview
1.1 Current Exam Facts & Logistics 1.2 Scoring, Section Minimums & the August 2026 Cut-Score Change 1.3 Official Blueprint & Study Strategy
2 Patient Care: Ethics, Legal Practice & Communication
2.1 Ethical & Legal Aspects of Patient Care 2.2 Interpersonal Communication & Patient Education 2.3 Physical Assistance, Monitoring & Sonographer Ergonomics
3 Patient Care: Safety, Emergencies & Infection Control
3.1 Medical Emergencies & Critical Findings 3.2 Infection Control & Hazardous Materials 3.3 Ultrasound Safety & Interventional Procedure Care
4 Image Production: Transducers & the Ultrasound Beam
4.1 Piezoelectric Effect & Transducer Construction 4.2 Beam Configuration: Near Field, Far Field & Focus 4.3 Transducer Types, Selection, Care & Malfunctions
5 Image Production: Pulse Characteristics & Resolution
5.1 Pulse Characteristics: PRF, PRP, SPL & Duty Factor 5.2 Resolution: Axial, Lateral, Temporal, Elevational & Contrast 5.3 Frequency, Bandwidth, Q Factor, Power, Pressure, Intensity & Amplitude
6 Image Production: Imaging Modes & Doppler Principles
6.1 B-Mode & M-Mode Imaging 6.2 Spectral Doppler: Pulsed Wave vs Continuous Wave 6.3 Color Doppler & Power Doppler
7 Image Production: Optimization Controls
7.1 Power, Gain, TGC, Depth & Focal Zone 7.2 Frame Rate, Line Density, Dynamic Range, Harmonics & Compounding 7.3 Doppler Optimization Controls
8 Image Production: Sound–Tissue Interactions
8.1 Speed of Sound & the Range Equation 8.2 Acoustic Impedance, Reflection, Refraction & Scattering 8.3 Attenuation, Absorption & Intensity
9 Image Production: Signal Processing, Display & Bioeffects
9.1 Receiver, Signal Processing & Analog-Digital Conversion 9.2 Postprocessing, Magnification, Panoramic & 3D/4D Imaging 9.3 Bioeffects & Output Display Measures
10 Image Production: Image Evaluation & Artifacts
10.1 Criteria for Diagnostic Quality & Annotation 10.2 Grayscale Artifacts 10.3 Doppler Artifacts
11 Image Production: Real-Time Interpretation & Informatics
11.1 Real-Time Imaging, Echogenicity & Echotexture 11.2 Color & Spectral Analysis: Measurements and Waveforms 11.3 Imaging Informatics: HIS, RIS, EMR, PACS & DICOM
12 Procedures: Abdominal & Transplant Vasculature
12.1 Aorta, Its Branches & the IVC 12.2 Portal Venous System & Hepatic Vasculature 12.3 Liver & Renal Transplant Sonography
13 Procedures: Liver
13.1 Liver Anatomy, Variants & Examination Technique 13.2 Diffuse Liver Disease 13.3 Focal Liver Lesions
14 Procedures: Biliary System, Pancreas & Spleen
14.1 Gallbladder & Bile Ducts 14.2 Pancreas 14.3 Spleen
15 Procedures: Urinary Tract, GI Tract & Other Abdominal Structures
15.1 Kidneys & Ureters 15.2 Bladder & Prostate 15.3 GI Tract, Adrenals, Lymph Nodes, Hernias & Peritoneal Cavity
16 Procedures: First-Trimester Obstetrics
16.1 Early Gestation: Normal Development & Structures 16.2 First-Trimester Measurements, Dating & Maternal Anatomy 16.3 First-Trimester Abnormalities
17 Procedures: Second/Third-Trimester Biometry & Fetal Survey
17.1 Standard Biometry: BPD, HC, AC, FL & Growth Assessment 17.2 Fetal Anatomic Survey: Head, CNS, Face & Spine 17.3 Fetal Anatomic Survey: Heart, Chest, GI, GU, Skeleton & Fetal Position
18 Procedures: Chromosomal, Genetic & Structural Abnormalities
18.1 Chromosomal & Genetic Abnormalities 18.2 Major Structural Anomalies by System 18.3 Fetal Infection, Neoplasms & Hydrops
19 Procedures: Placenta, Amniotic Fluid, Cord & Cervix
19.1 Placenta: Normal, Previa, Abruption & Accreta 19.2 Amniotic Fluid Assessment & Growth Disorders 19.3 Umbilical Cord & Cervical Assessment
20 Procedures: Fetal Assessment, Doppler & Multiple Gestation
20.1 Biophysical Profile & Fetal Surveillance 20.2 Fetal & Uteroplacental Doppler 20.3 Multiple Gestations, Assisted Reproduction & Maternal Disease
21 Procedures: Gynecology — Uterus
21.1 Uterine Anatomy, Myometrium & Fibroids 21.2 Endometrium: Cyclic Changes, Hyperplasia & Cancer 21.3 Cervix & Congenital Uterine Anomalies
22 Procedures: Gynecology — Adnexa & Pelvis
22.1 Ovaries: Normal, Functional Cysts & Benign Masses 22.2 Ovarian Malignancy, Torsion & Fallopian Tubes 22.3 Cul-de-Sac, Vagina & Pelvic Floor
23 Procedures: Neck & Scrotum
23.1 Thyroid & Parathyroid 23.2 Salivary Glands & Neck Lymph Nodes 23.3 Scrotum & Testes
24 Procedures: Breast & Peripheral Vascular
24.1 Breast & Axilla 24.2 Venous Extremity Doppler 24.3 Carotid Doppler & Post-Catheterization Complications
25 Procedures: Pediatric, Interventional & Miscellaneous
25.1 Neonatal Head, Spine & Hip Sonography 25.2 Pediatric GI & Noncardiac Chest 25.3 Ultrasound-Guided Interventions, MSK & Superficial Masses
13.2 Diffuse Liver Disease
Key Takeaways Explain This Topic AI
Hepatic steatosis produces a diffusely hyperechoic liver with increased attenuation; the classic comparison is a bright liver against a darker right renal cortex (hepatorenal contrast)
Focal fatty sparing classically occurs adjacent to the gallbladder fossa and porta hepatis, has geographic margins, and does not displace vessels
Acute hepatitis may show a hypoechoic 'starry sky' liver in which the portal triad walls stand out brightly, but the liver can also appear entirely normal
Cirrhosis shows coarse echotexture, surface nodularity, right lobe atrophy, and caudate lobe hypertrophy; a caudate-to-right-lobe width ratio above 0.65 is suggestive
Portal hypertension is suggested by portal vein diameter over 13 mm, splenomegaly, ascites, portosystemic collaterals, and dampened (monophasic) hepatic vein waveforms
Last updated: July 2026
Diffuse liver diseases alter the entire parenchyma rather than forming discrete masses, so the exam tests pattern recognition against the normal mid-level, homogeneous baseline.
Fatty Infiltration (Hepatic Steatosis)
Hepatic steatosis is the most common diffuse liver abnormality, seen with obesity, diabetes, alcohol use, and hyperlipidemia. Sonographic features:
Diffuse increase in echogenicity — the liver appears abnormally bright compared with the right renal cortex ( hepatorenal contrast ).
Increased attenuation — the sound beam is absorbed, so the deep liver and the diaphragm become hard to visualize; you may need to lower the frequency.
Poorly visualized vessel walls as parenchymal echogenicity approaches that of the portal triads.
Focal fatty sparing is the classic mimic: a hypoechoic, geographic region of normal tissue surrounded by bright fatty liver, typically adjacent to the gallbladder fossa and the porta hepatis (segment IV). Unlike a true mass, it has geographic rather than rounded margins , causes no contour bulge, and vessels course through it undisturbed . The reverse pattern, focal fatty infiltration, is a hyperechoic patch in the same typical locations.
Hepatitis
Acute hepatitis often looks sonographically normal. When abnormal, the parenchyma becomes hypoechoic from edema while the portal triad walls remain bright — the 'starry sky' liver . The gallbladder wall may be thickened. Chronic hepatitis produces a coarsened, increasingly echogenic texture that overlaps with early cirrhosis. Laboratory correlation is essential: acute hepatitis elevates alanine aminotransferase (ALT) and aspartate aminotransferase (AST) disproportionately, often with hyperbilirubinemia.
Practical Points on Steatosis and Hepatitis
Steatosis can be loosely graded: mild disease brightens the liver slightly with the diaphragm and vessels still seen; moderate disease blurs vessel walls and the deep diaphragm; severe disease renders the posterior liver nearly invisible at standard settings. Because fatty change is reversible , the finding is reported with the clinical context (obesity, diabetes, alcohol, steroids, chemotherapy). Viral hepatitis is caused most often by hepatitis A (fecal-oral, self-limited), hepatitis B , and hepatitis C (both blood-borne; both can become chronic and progress through fibrosis to cirrhosis and hepatocellular carcinoma — alcohol-associated liver disease is now the leading indication for liver transplantation in the United States, having overtaken hepatitis C after direct-acting antivirals came into use). Remember that ultrasound's role in acute hepatitis is largely to exclude biliary obstruction as the cause of jaundice, because the parenchyma may look entirely normal.
Cirrhosis
Cirrhosis is end-stage fibrosis with regenerative nodules, most often from chronic viral hepatitis or alcohol. Sonographic signs:
Coarse, heterogeneous echotexture and increased attenuation.
Surface nodularity , best appreciated along the liver edge when ascites provides an acoustic window, or with a high-frequency linear transducer.
Lobar redistribution : right lobe atrophy with hypertrophy of the caudate and left lobes . A caudate-to-right-lobe width ratio greater than 0.65 is a classic indicator of cirrhosis.
Signs of Portal Hypertension
Portal vein diameter exceeding about 13 mm , with loss of normal respiratory variation.
Splenomegaly (spleen longer than roughly 12-13 cm) and ascites .
Portosystemic collaterals , including a recanalized paraumbilical vein within the ligamentum teres and coronary (left gastric) varices.
Advanced disease: slowed portal venous velocity, bidirectional flow, or frankly hepatofugal flow (away from the liver).
Doppler in Cirrhosis
The normal hepatic vein waveform is triphasic , reflecting cardiac cycle pressure changes transmitted from the right atrium. In cirrhosis the stiff, fibrotic parenchyma buffers these pulsations, so the tracing becomes dampened or monophasic — an early, sensitive clue. Portal venous flow normally is continuous, mildly undulating, and hepatopetal (toward the liver) at roughly 15-30 cm/s; velocity falls as portal hypertension worsens.
Storage and Deposition Disorders
Glycogen storage disease (von Gierke, type I): marked hepatomegaly with diffusely increased echogenicity resembling fatty liver; patients have an increased incidence of hepatic adenomas .
Hemochromatosis : iron deposition produces increased echogenicity and can progress to cirrhosis with an elevated hepatocellular carcinoma risk; serum ferritin and transferrin saturation are elevated.
- Disease Echogenicity Key lab correlation
- Steatosis Diffusely increased Often mild ALT/AST rise; metabolic risk factors
- Acute hepatitis Normal or decreased ('starry sky') Markedly elevated ALT/AST, bilirubin
- Cirrhosis Coarse, heterogeneous Low albumin, prolonged INR/PT, thrombocytopenia
- Hemochromatosis Increased High ferritin and transferrin saturation
- Putting the Differential Together
A few extra patterns round out this section. Regenerative nodules in cirrhosis are usually isoechoic and invisible; dysplastic nodules are premalignant and warrant shorter-interval surveillance. Wilson disease (copper deposition) and alpha-1 antitrypsin deficiency are less common metabolic causes of a cirrhotic-looking liver in younger patients. When the liver is enlarged and hyperechoic with normal labs, think fatty infiltration or glycogen storage disease; when it is shrunken, coarse, and nodular with splenomegaly and ascites, think cirrhosis with portal hypertension. Ultrasound is also the first-line tool for grading the complications: it detects ascites , measures spleen size, maps collateral vessels , and screens the parenchyma for the development of hepatocellular carcinoma , which is why cirrhotic patients enter surveillance programs rather than one-time imaging.