The imaging techniques and diagnostic performance of ultrasound, CT, and MRI in detecting liver steatosis and fat quantification: A systematic review

The most prevalent liver disorder is hepatic steatosis. The gold standard for the assessment of liver fat is biopsy. However, several less invasive diagnostic imaging techniques can be used for more detailed information about hepatic tissue or even replace biopsy. In this review study, we have presented the impact of ultrasound (US), computed tomography (CT), and magnetic resonance imaging (MRI) to detect or even quantify the fat content of the liver. US is a relatively cheap, widely available and ionizing radiation-free technique. However, it cannot provide images of the entire liver. New developments increase its diagnostic accuracy even for mild and moderate liver steatosis. CT is a fast and available imaging method; however, it uses ionizing radiation. The diagnostic accuracy of this technique can not exceed the US and MRI, but its information will be useful for further computerized analysis. Despite the disadvantages of MRI including higher cost and time, its diagnostic performance in steatosis grading is greater than US and CT. The MRI methods for liver fat measurements can be considered an alternative reference standard for liver biopsy. In this systematic study, we explained their techniques, diagnostic accuracy, advantages, limitations, and future applications.