Fatty liver disease that is not due to excessive alcohol consumption is becoming more common. The disease is characterized by the accumulation of fat in the liver, and in patients with untreated fatty liver disease, the condition can eventually lead to inflammation, the formation of scar tissue and a significantly increased risk of chronic liver disease or liver cancer.
Globally, it is believed that around 24% of the population has fatty liver disease, and the number is rising. Early diagnosis of these patients is important because treatment in the form of lifestyle changes or medical or surgical obesity treatment can reverse the condition and thus reduce the risk of permanent liver damage. Today, there are no methods that can easily and painlessly measure the percentage of fat in the liver, which makes it difficult to diagnose the condition or to follow the development over time.
In this project, we further develop and optimize a new ultrasound method for estimating fat content. The method is based on non-linear acoustics and estimates a material parameter in the tissue which shows a good correlation with fat content. It involves the use of a specially made ultrasound probe that can send pulses containing two different frequencies at the same time.
The measurement method has been tested in a laboratory study (in vitro) on materials with added levels of fat and in an animal study (in vivo) where rats were fed a high-fat diet to develop varying degrees of fatty liver. In both cases, we found that there was agreement between the fat level estimated with the ultrasound method and the actual fat content.
As part of the project, we are developing a new ultrasound probe that is adapted to measurements on patients with obesity and suspected fatty liver disease.