Validity of real time ultrasound in the diagnosis of hepatic steatosis: A prospective study

Abstract

Background/Aims: Ultrasound is used to screen for hepatic steatosis, the most common liver disease in the United States. However, few studies have prospectively evaluated the accuracy of ultrasound to diagnose hepatic steatosis. Therefore, a double blinded prospective study was performed in consecutive patients undergoing liver biopsy to evaluate the accuracy of ultrasound to diagnose hepatic steatosis. Methods: Real time ultrasound was performed just prior to the biopsy by a single investigator masked to the clinical diagnosis. The liver biopsy was reviewed by a pathologist masked to the clinical indication or sonographic findings Results: Of 73 consecutive patients studied,macrovesicular steatosis of any severity on biopsy was found in 46 (63%) and micro vesicular fat found in 51 (69.9%). The overall impression of the sonographer for the presence of macrovesicular hepatic steatosis of any degree had a sensitivity of 60.9% and a specificity of 100%. The sensitivity increased to 100% and the specificity to 90% when there was ≥ 20% of fat. The zonular distribution of the fat did not alter the diagnostic accuracy of ultrasound. Ultrasound had a poor yield in the diagnosis of microvesicular fat with an overall sensitivity of 43% and a specificity of 73%. The combination of increased echogenicity and portal vein blurring on ultrasound had the greatest sensitivity in the diagnosis of hepatic steatosis. Conclusion: Real time ultrasound using a combination of sonographic findings has a high specificity but underestimates the prevalence of hepatic steatosis when there is less than ≥ 20% fat.

Metformin versus dietary treatment in nonalcoholic hepatic steatosis: a randomized study

“…They had, therefore, no features predicting liver fibrosis. Finally, a recent prospective study 51 evaluated US accuracy in NAFLD patients undergoing liver biopsy. US had a high sensitivity (100%) and specificity (90%) in these patients, especially when the total area of hepatocytes with steatosis exceeded 20%.…”

The Riddle of Nonalcoholic Fatty Liver Disease: Progression From Nonalcoholic Fatty Liver to Nonalcoholic Steatohepatitis

“…Though liver histology is the Keywords: adiponectin, cytokines, gut microbiota, lipotoxicity, PNPLA3gold standard in diagnosis of NAFL, the commonest method used is transabdominal ultrasonography which has a sensitivity of 100% and specificity of 90% when fat on liver biopsy exceeds 20%. 16 Other non-invasive modalities used to diagnose NAFL includes transient elastography (Fibroscan) and Acoustic Resonance Magnetic Imaging (ARFI) which measures liver stiffness and corresponds to presence of fibrosis. Magnetic resonance spectroscopy is a quantitative method of measuring liver fat but is limited in clinical use due to lack of widespread availability and cost.…”

Noninvasive imaging assessment of non-alcoholic fatty liver disease: Focus on liver scintigraphy

“…One study reported a sensitivity of US of 91% and specificity of 93% in 235 patients with ≥ 30% steatosis on biopsy [11] . In the same manner, a prospective study by Dasarathy et al [12] reported 90% sensitivity with US when steatosis was > 20% on biopsy. However, the sensitivity is low when the degree of steatosis is < 20%-30% [12,13] .…”

“…In the same manner, a prospective study by Dasarathy et al [12] reported 90% sensitivity with US when steatosis was > 20% on biopsy. However, the sensitivity is low when the degree of steatosis is < 20%-30% [12,13] . Moreover, the sensitivity and specificity of US are considerably reduced in the presence of obesity [14] .…”