Letter to the Editor: “Diagnostic performance of ultrasound attenuation imaging for assessing low-grade hepatic steatosis”

by Karen Cifuentes G, Santiago Aristizabal, Camilo Soler,Diego Aguirre (cifuentesg.karen@gmail.com)

Diagnostic performance of ultrasound attenuation imaging for assessing low-grade hepatic steatosis

Dear Editor,

We read with great interest the recently publication in European Radiology by Jang J.K., et al, entitled “Diagnostic performance of ultrasound attenuation imaging for assessing low‐grade hepatic steatosis” [1].

As we know, the prevalence of hepatic steatosis and nonalcoholic fatty liver disease (NAFLD) is rapidly growing worldwide including in pediatric population, and being considered in some countries as a public health problem; that is why we like to thank and congratulate the authors work, on the effort in conducting a study to investigate the diagnostic performance of attenuation imaging (ATI) for the detection and assessment of low-grade hepatic steatosis, considered as a non-invasive method.

Percutaneous nontargeted liver biopsy is considered the gold standard for assessment of hepatic steatosis, however the disadvantages of this diagnostic approach are well known, and the emergence of noninvasive imaging biomarkers are leading to rethinking of the current diagnostic approach [2]. Liver biopsy is an invasive procedure that is difficult to perform routinely, thus limiting patient follow-up, and this is where, non-invasive and quantification methods such as magnetic resonance imaging and ultrasound including attenuation imaging (ATI) and controlled attenuation parameter (CAP) from transient elastography (TE) play a significant role.

The detection and quantification of hepatic steatosis are crucial for patient management, and we would like to ask the authors, after carrying out this study, what are their opinions and concerns about routinely performing ATI and CAP for fatty liver quantification and follow-up.

Also, as we know US-based methods are not specific to fat; while liver fat attenuates sound waves, many other liver pathologies such as hepatitis, hemochromatosis or fibrosis can also affect sound waves in the same way [2], and we would like to ask the authors about iron liver deposit consideration because it was not specifically mentioned in the study.

Finally, we would like to highlight, the magnetic resonance imaging proton density fat fraction (MRI-PDFF) as an emerging an increasingly accepted quantitative biomarker of liver fat which has demonstrated an excellent diagnostic value for assessment hepatic fat content and classification of histologic steatosis [3, 4] and it would be very interesting to perform a study which includes MRI-PDFF and the results of your study.