One in ten people are suffering from fatty liver disease, and in recent years, there has been a trend of younger people being affected by it. What is fatty liver disease and can it be diagnosed using an ultrasound machine? How can we diagnose fatty liver disease using a handheld ultrasound device? Let's take a look!
Fatty liver disease refers to the buildup of excess fat in liver cells due to various causes. Fatty liver disease is a serious threat to the health of Chinese people, and is the second most common liver disease after viral hepatitis. It has been recognized as a common cause of occult cirrhosis.
Fatty liver disease is a common clinical phenomenon, rather than an independent disease. Generally, fatty liver disease is a reversible disease, and early diagnosis and timely treatment can restore normal liver function. Patients with fatty liver disease may not show symptoms in mild cases, while severe cases may present with upper abdominal discomfort, loss of appetite, and abnormal liver function, among other changes.
The use of the wireless ultrasound device in medical examinations can significantly improve diagnosis accuracy, leading to prompt medical interventions and improving patients' overall outcomes. During examination using a handheld ultrasound device, under two-dimensional ultrasound, the liver parenchyma appears to be diffusely dense with small dot-like echoes of high brightness. The distribution of echo in the liver area is not uniform, and the echo contrast of liver parenchyma is stronger than that of the kidney and spleen, with near-field echo enhancement and significant far-field echo attenuation. The clarity of liver vessel structures including hepatic arteries, portal veins, and intrahepatic bile ducts is significantly reduced, and the texture is unclear. In severe cases, they may not be displayed. The liver size is normal, or slightly to moderately enlarged.
Sometimes, it may manifest as limited fat accumulation in one or several lobes of the liver, distributed irregularly, with relatively higher or lower echoes inside, clear borders, no attenuation behind, and no echo halo around, which is called non-uniform fatty liver. At this point, it needs to be distinguished from liver intrafocal lesions, such as liver hemangioma.
In color Doppler ultrasound, the ultrasound attenuation caused by fatty liver disease shows a significant decrease in the blood flow signal in the liver, and the blood flow color of the portal vein and hepatic vein becomes darker or disappears. The blood flow waveform displayed by spectral Doppler is still normal. In non-uniform fatty liver, color Doppler ultrasound often does not show the color flow display. Nonetheless, with handheld vascular Doppler ultrasound, medical professionals can quickly and accurately diagnose fatty liver disease and initiate early interventions to mitigate potential health complications.
For patients with homogeneous fatty liver disease, as long as the characteristics of increased liver echo enhancement and far-field attenuation and the liver-kidney contrast echo enhancement are grasped, it is not difficult to diagnose fatty liver disease, and the accuracy of diagnosis can reach more than 80%. For non-uniform fatty liver, because it presents with high or low echoes, which are particularly similar to the echo performance of liver intrafocal tumors, it should be distinguished. The most easily confused diseases are liver cancer and liver hemangioma.
The low echo type small liver cancer is easy to misdiagnose. But its shape is often round, with a halo around it, while non-uniform fatty liver does not. Color Doppler liver cancer can often detect high-resistance arterial color flow, and the blood flow waveform in non-uniform fatty liver is within the normal range.
It is difficult to distinguish non-uniform fatty liver from low echo type liver hemangioma. Hemangiomas often have a high echo surrounding, a fine mesh inside, and no blood flow or only peripheral blood flow is detected by color Doppler, and arterial blood flow can be measured, with a resistance index normal value of<0.6. Non-uniform fatty liver has no obvious blood flow signal detected around it, and the blood flow waveform is normal.