Introduction:
A novel, non-invasive, quick, repeatable technique called transient elastography (FibroScan) enables the assessment of liver fibrosis by the measurement of liver stiffness. Liver stiffness values in cirrhotic patients vary from 12.5 to 75.5 kPa. The clinical significance of these levels is uncertain, though. This prospective study aimed to assess how well liver stiffness measurement works in identifying cirrhosis in patients with long-term liver illness.
What Is Fibroscan?
Transient elastography is a non-invasive method used by Fibroscan to evaluate the liver's "hardness" or stiffness. The velocity of a vibration wave also referred to as a "shear wave," is produced on the skin and is used to measure the hardness of the liver. The duration of the vibration wave to reach a specific depth within the liver is used to calculate the shear wave velocity. A graphical representation of this is on the screen. The degree of hepatic fibrosis can be estimated from liver hardness since fibrous tissue is harder than normal liver. In order to enhance test reliability, ten valid readings must be obtained, with the values stated in kilopascals (kPa) and an interquartile range of ≤30 % of the median value and at least a 60 % success rate.
What Are the Indications of Fibroscan?
A noninvasive diagnostic ultrasonography tool called Fibroscan is used to quantify liver scarring, or fibrosis, which is brought on by various liver conditions. Outpatient Fibroscan testing is rapid, painless, and simple, much like a typical ultrasound exam. It offers a non-surgical alternative to the usual liver biopsy for assessing liver damage.
The main purpose of fibroscan is to determine the extent of liver scarring that is present or the stage of liver disease. This is incredibly helpful for evaluating patients who have chronic liver illnesses, such as fatty liver, chronic alcohol addiction, chronic hepatitis B, and chronic hepatitis C. The idea is that the liver stiffness reading will increase with increased fibrosis and scarring. Individuals could use this reading to
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Determine the current level of liver damage.
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Track the progression or regression of the disease using repeated measurements to inform the prognosis and subsequent care, such as treatment.
Conditions where the Fibroscan is indicated:
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Liver illness caused by alcohol hepatitis B and hepatitis C.
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Steatohepatitis without alcohol (NASH) - a condition in which the liver builds up excessive fat deposits
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Hereditary illnesses like hemochromatosis and Wilson's disease- a rare inherited condition that causes copper levels to build up in several organs
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Autoimmune hepatitis - a condition where the body's infection-fighting system (immune system) attacks the liver cells.
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Cirrhosis - a condition in which the liver is scarred and permanently damaged.
What Are the Drawbacks of Fibroscan?
Since transient elastography does not evaluate fibrosis directly, it is possible to observe false elevation or an overestimation of liver fibrosis for a variety of reasons. Consequently, it is important to interpret liver stiffness data cautiously and take these possible confounding factors into account.
Potential causes for a Fibroscan overestimation of fibrosis
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Inflammation of the liver (active hepatitis).
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Cholestasis (such as biliary blockage).
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Large lesions (such as tumors) in the liver.
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Congestion of the liver and heart failure.
Furthermore, some patients are unable to receive correct readings. Patients who exhibit these traits are more likely to experience failure or untrustworthy readings.
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Being obese (BMI >30 - 35 kg/m2).
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Advanced age.
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Ascites is present.
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Characteristics of the metabolic syndrome: elevated waist circumference, hypertension, and type 2 diabetes.1
This is so that readings from the ultrasound-based approach, which depends on a sufficient visualization of the liver, can be obtained. According to research, the standard M probe yields accurate results in less than 50 % of individuals with a body mass index (BMI) of greater than 35 kg/m2. The creation of various probes, like the XL probe, which enables deeper vibration wave penetration, helps partially solve this issue.
Furthermore, an S probe could be needed to get readings from kids or individuals with extremely narrow rib gaps. According to a big European investigation, approximately 20 % of patients did not receive correct findings using FibroScan. Among the variables linked to reading failure or unreliability were aging, having a BMI greater than 30 kg/m2, and having characteristics of metabolic syndrome.
Although the presence of ascites hinders the vibration wave from propagating and sometimes leads to failure to get readings, there are no absolute contraindications for the test. Additionally, the device's manufacturer warns against using it in patients who have pacemakers or who are pregnant.
How Is Fibroscan Done?
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Before the fibrosis, the individual is instructed to eat nothing and drink nothing for three hours before the surgery, including water.
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Arrive fifteen minutes early to the procedure if possible.
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FibroScan is a painless diagnostic procedure that does not include any form of anesthesia.
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Typically, the process takes five minutes. About thirty minutes will pass during the entire appointment.
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Individual’s right arm will be elevated behind the head, and the right abdomen region will be exposed as they lie on their back for the procedure.
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A nurse practitioner or physician's assistant will place a noninvasive probe over the liver after a water-based gel has been applied to the skin.
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As the probe applies ultrasonic waves to the area for measurement, a tiny vibration can occur at the tip of the probe during the exam.
The interpretation of the results may vary depending on the cause of the liver disease. Consequently, it is advisable to evaluate the data in conjunction with other clinical and biochemical criteria and, ideally, by a specialist in the management of chronic liver disease.
Conclusion:
Fibroscan has been used not only to measure liver fibrosis but also to predict survival in patients with liver disease, evaluate patients with portal hypertension, and assess the recurrence of illness after liver transplantation. Furthermore, individuals with breast cancer, prostate cancer, and other illnesses where fibrosis is a significant factor are being assessed using this method. It is useful to assess liver stiffness in order to diagnose cirrhosis and fibrosis, regardless of the underlying etiology of liver illness. In patients with cirrhosis, values varied from 17.6 to 75.4 kPa. Measuring liver stiffness can be a reliable method of determining how severe cirrhosis is. To screen for cirrhosis-related complications and conduct attentive monitoring, long-term cohort research utilizing FibroScan prediction of cirrhosis complications is necessary.
