Early detection of fatty liver disease can be lifesaving. Fatty liver or hepatic steatosis occurs when excess fat builds up in the liver. This condition leads to a series of complications which are difficult to reverse. Therefore early medical intervention is required. An early diagnosis can stop fatty liver disease from deteriorating. At present there are no diagnostic techniques for early detection of liver disease. In a ground breaking research scientists from Massachusetts Institute of Technology (MIT) have developed a nuclear magnetic resonance (NMR) based diagnostic tool. This tool can be used for early, non-invasive detection of fatty liver disease and liver fibrosis even before its symptoms appear. Their work has been published in Nature Biomedical Engineering.
Liver is a vital organ in our body. It extracts nutrient from food and filters out harmful substance from the blood. Small amount of fat in the liver is normal. However, when excess fat accumulates in the liver it leads to a health problem known as fatty liver. When the body produces too much fat or does not metabolize efficiently the excess fat gets stored in the liver. This leads to fatty liver disease.
Two main forms of fatty liver disease:
- Alcoholic fatty Liver disease- Accumulation of fat in the liver due to excessive alcohol consumption causes Alcoholic Liver disease.
- Non Alcoholic fatty liver disease – Accumulation of fat in the liver of individuals who are not heavy drinkers leads to this condition. The exact cause of Non Alcoholic fatty liver disease is not clear. Possible causes of this condition could be obesity, high blood sugar, insulin resistance, high levels of triglyceride, fat in blood.
With time fatty liver disease worsens progressing through further complicated stages. Fatty liver first leads to inflammation of the liver followed by fibrosis (inflammation of the liver leading to scarring). Widespread scarring and severe fibrosis leads to cirrhosis eventually leading to liver failure. Currently there are no early diagnostic tools for this life threatening disease. Until the patient experiences symptoms like fatigue, abdominal swelling and jaundice, fibrosis is usually not detected or diagnosed.
At present the best method to diagnose and determine the severity of the fatty liver disease is a liver biopsy. Biopsy is invasive hence a surgical procedure is required. During this procedure a needle is inserted into the liver to remove a small piece of tissue which will be used determine the level of scarring and fatty liver disease. Sometimes this test does not give the accurate result. The test fails if the sample has been extracted from a part of the liver that is not fibrotic. Non-invasive, low cost diagnostic method for tracking the progress of liver disease from fatty liver to worse conditions is currently not available.
In a novel approach researchers from MIT have designed a non-invasive diagnostic tool based on Nuclear Magnetic Resonance (NMR). Even before obvious symptoms appear an individual can be screened for fatty liver disease. This NMR based device is small enough to fit on a table making it convenient.
The team has developed this device by modifying a detector which is used to measure the hydration levels of a patient before and after they undergo dialysis. The detector monitors fluid volume in skeletal muscle of patients. It uses Nuclear Magnetic Resonance (NMR) to monitor changes in magnetic properties of hydrogen atoms of water in the patient’s muscle tissue. Based on this concept the team has developed a similar device which can be used to identify liver diseases. Since water diffuses slowly through fatty tissue or fibrosis, monitoring how water moves through the tissue over time can measure the level of fatty or scarred tissue present in the liver. The NMR based device will basically track how water diffuses through tissue which will thereby show how much fat is present in the liver tissue.
Under lab conditions the team has tested this novel device in animal model (mice model). The team has demonstrated that results can be obtained in 10 minutes. They have observed that the NMR based device could determine fibrosis with 86 percent accuracy. Also it could detect fatty liver disease with 92 percent accuracy. To further reduce the detection time the team is trying to improve the signal to noise ratio of the detector.
As of now the Nuclear Magnetic Resonance (NMR) based device can scan up to 6 millimetres of depth below the skin. Thus it is presently suitable for monitoring mouse liver and human skeletal muscle. The research team is trying to develop a new version of the device which can penetrate deeper below the tissue. The improved version of the device will be suitable for liver diagnosis and testing in human patients.
According to the research team a fully automated low cost non-invasive NMR based device at the point of care would make liver disease diagnostic tools easily accessible to patients. Liver fibrosis cannot be reversed but it can be stopped or slowed down through interventions like dietary changes and exercise. Hence early detection is necessary for timely medical intervention. This NMR based device will help screen patients with the risk of developing fibrosis even before its symptoms appear or also identify early stages of fibrosis. According to the researchers this diagnostic tool will also help in drug development and new treatment method. With the help of this device doctors can easily non-invasively monitor the progress and response of liver fibrosis to the new treatment methods. Another application for this NMR based device would be to test human liver for transplant.
It is evident early diagnosis of fatty liver disease can help prevent further complications and liver failure. Early diagnosis will ensure earlier medical intervention which can halt further deterioration of the organ. Presently fatty liver can be detected only when the obvious symptoms appear. Currently biopsy is the best diagnostic tool for fatty liver disease detection. However biopsy has a number of disadvantages. The MIT team has developed an innovative non-invasive, low cost diagnostic tool which can be used to detect fatty liver disease even before it symptoms appear. This NMR based device will save lives by ensuring timely diagnosis of the disease.
Ashvin Bashyam, Chris J. Frangieh, Siavash Raigani, Jeremy Sogo, Roderick T. Bronson, Korkut Uygun, Heidi Yeh, Dennis A. Ausiello, Michael J. Cima. A portable single-sided magnetic-resonance sensor for the grading of liver steatosis and fibrosis. Nature Biomedical Engineering, 2020; DOI: 10.1038/s41551-020-00638-0
Available from: www.nature.com/articles/s41551-020-00638-0