Liver elastography

Liver elastography is a non-invasive medical examination technique used to assess the level of liver tissue stiffness. It is often used in the diagnosis and monitoring of liver diseases such as cirrhosis, hepatitis, and fatty liver dystrophy. This method allows doctors to assess the extent of liver damage without the need for a biopsy, which is an invasive procedure and carries risks for the patient.

The principle of liver elastography is to measure the elasticity or stiffness of the liver. Normally, in a healthy liver, the tissues are soft and elastic. However, in cases of liver disease such as cirrhosis, the liver tissues become stiff due to the formation of fibrotic tissues. Elastography uses acoustic waves to determine the level of stiffness of the liver tissue. The patient usually undergoes an ultrasound (ultrasound scan) of the liver using a special machine that can measure the level of elasticity.

The data obtained allows doctors to assess the condition of the liver and determine the degree of fibrosis. This can be helpful in deciding the diagnosis, treatment and monitoring of liver disease. Liver elastography is considered a safe and non-invasive procedure and can be performed on an outpatient basis without the need for hospitalization.

Liver elastography is an important tool in clinical medicine for diagnosing and monitoring liver disease, and it avoids more invasive methods of assessing liver stiffness such as biopsy.

Indications for the procedure

Liver elastography may be recommended by your doctor in the following cases:

1. Diagnosis of cirrhosis: Elastography can be used to determine the degree of liver fibrosis, which helps doctors assess the presence and severity of cirrhosis.
2. Diagnosis of hepatitis: Elastography may be useful to determine the degree of fibrosis caused by chronic hepatitis B, hepatitis C, or other viral hepatitis.
3. Assessment of fatty liver dystrophy: The method can be used to assess the degree of fatty infiltration of the liver, which is a characteristic feature of nonalcoholic fatty liver disease (NAFLD) or nonalcoholic steatohepatitis (NASH).
4. Patient Monitoring: Elastography can be used to monitor patients with known liver disease to assess the dynamics of changes in liver stiffness over time.
5. Evaluating the effectiveness of treatment: Once treatment for liver disease, such as hepatitis or cirrhosis, has been started, elastography can be used to assess how well treatment is improving liver health.
6. Screening patients at risk: In some cases, doctors may recommend elastography to patients who have risk factors for liver disease, such as diabetes, obesity, or alcohol abuse.

The approach to the use of liver elastography may vary depending on the specific clinical case and the physician's recommendations. This method helps to assess the liver without the need for biopsy, making it a valuable tool in the diagnosis and monitoring of liver disease.

Preparation

Preparation for liver elastography is usually quite simple and requires no special precautions. Here are some general guidelines:

1. Fasting required: Liver elastography does not usually require fasting or special dietary restrictions before the procedure. You can eat and drink as usual before the examination.
2. Medication adherence: If you are taking any medications on a regular basis, you should generally continue to take them at their usual times and dosage. If you have any special instructions from your doctor, then follow them.
3. Inform your doctor: It is important to inform your doctor of any medical conditions, medications, and allergies you have. This will help your doctor to better evaluate your medical history and perform liver elastography with all factors in mind.
4. Comfortable clothing: You may wear comfortable clothing as you may be asked to lie on your back or side for the procedure. Special clothing is not usually required.
5. Avoid alcohol: Alcohol should be avoided before the procedure, as alcohol can affect the results and accuracy of elastography.
6. Certain Conditions: In some cases, if you have certain conditions, such as ascites (fluid buildup in the abdomen), your doctor may recommend additional preparation or additional tests.

It is important to discuss all details of your preparation with your doctor or health care provider who ordered your liver elastography. He or she will provide you with specific instructions that are appropriate to your medical history and needs.

The device for carrying out the procedure

A special medical device called an elastograph (or elastography machine) is used to perform a liver elastography procedure. There are two main types of liver elastography: acoustic elastography and transient elastography (TE). Let's take a look at both types of machines:

1. Acoustic elastography: This method uses ultrasound waves to measure the stiffness of liver tissue. When acoustic elastography is performed, the patient is given a comfortable position, usually on his or her back. The doctor or technician applies a gel to the skin of the patient's upper abdomen and applies a skin applicator (similar to an ultrasound transducer) to the area. The machine then generates a soft acoustic wave that propagates through the liver tissue. During the study, the time it takes for this wave to travel through the liver is measured and the degree of liver stiffness is calculated based on this measurement.
2. Transient Elastography (TE): This method also uses ultrasound waves, but in this case the transient wave is generated using a special mechanical device that is worn on the skin. The transient wave allows for a more accurate measurement of liver stiffness. This method is usually part of more modern ultrasound machines and provides more accurate results.

Both methods of liver elastography are non-invasive and painless, and they provide a quick assessment of the degree of fibrosis (stiffness) in the liver. The results can be presented as an image or a numerical value that reflects tissue stiffness. This data is used by doctors to diagnose and monitor liver diseases such as cirrhosis and hepatitis.

Technique of the liver elastography

A special medical device called an "elastograph" is used to perform a liver elastography procedure. This machine uses ultrasound wave technology to measure the stiffness or elasticity of liver tissue. Here's how the procedure using an elastograph works:

1. The patient lies on his or her back or side on the test couch.
2. The doctor or ultrasound technologist (ultrasound technologist) applies a gel to the skin in the area of the liver. This gel helps improve contact between the skin and the transducer of the machine.
3. The elastograph sensor, which is similar to an ultrasound transducer, is gently pressed on the skin in the liver area. The transducer sends ultrasound waves inside the liver and then measures how fast these waves travel through the liver tissue.
4. Based on measurements of the velocity of ultrasound waves traveling inside the liver, the device calculates the stiffness of the tissue. This can be presented in various formats, such as kilopascals (kPa) or megapascals (MPa), and indicates the level of fibrosis or liver stiffness.
5. The entire process usually takes only a few minutes and usually does not cause discomfort or pain to the patient.

The data obtained can be evaluated by a physician to determine the condition of the liver and the degree of fibrosis. Liver elastography is a rapid and non-invasive method of assessing liver health and is the preferred alternative to liver biopsy for determining the degree of fibrosis.

Contraindications to the procedure

Liver elastography (or FibroScan elastography) is a relatively safe and minimally invasive procedure to assess the degree of fibrosis (fibrosis) in the liver. However, some patients may have contraindications or limitations to this study. Contraindications may include:

1. Presence of metal implants: If a patient has metal implants such as pacemakers, artificial valves or other metal devices in the body, this may be a contraindication as the ultrasound vibration used during elastography may affect the function of these devices.
2. Obesity: In cases of extreme obesity (3rd degree obesity), there may be a limitation in elastography because the thickness of subcutaneous adipose tissue may make it difficult to obtain accurate results.
3. Ascites (fluid accumulation in the abdomen): Ascites can affect the accuracy of elastography results because the presence of fluid in the abdomen can affect the distribution of ultrasound waves.
4. Severe pain or discomfort: If the patient is experiencing severe pain or discomfort in the liver area, this may be a contraindication for the study.
5. Skin diseases in the area to be scanned: The presence of certain skin conditions, such as severe inflammation or infections, may be a contraindication as they may affect the quality and accuracy of the scan.

These contraindications and limitations should be considered on an individual basis, and the decision to perform liver elastography should be made by your physician or health care provider based on your medical history and current health status. If you have any concerns or questions about having this procedure, be sure to discuss them with your doctor.

Normal performance

Normal liver elastography values may vary slightly depending on the specific type of machine and the technique used in the medical facility. In addition, normal values may be expressed in different units of measurement in different countries. Generally, however, the degree of liver stiffness, measured in kilopascals (kPa), can be interpreted as follows:

1. Normally healthy liver: Normally, the liver in an adult has a degree of stiffness lying between 2 and 5 kPa.
2. Soft liver: Values less than 2 kPa are generally considered a sign of a soft liver, which is a normal condition.
3. Rigid liver: Values over 5-6 kPa may indicate increased liver stiffness, which may be associated with fibrosis or other liver disease.

It is important to note that the interpretation of liver elastography results should be performed by a physician, taking into account all clinical data of the patient. Normal values may vary depending on age, gender, ethnicity and other factors.

If you have liver elastography results and are interested in their interpretation, be sure to discuss them with your physician. He or she will be able to evaluate your results and explain whether you have any abnormalities or changes in your liver that require medical intervention or additional testing.

Complications after the procedure

Liver elastography is generally considered a safe and non-invasive procedure, and complications are rare. However, as with any medical procedure, there is a small risk of unforeseen events. Here are some of the possible complications that can occur after liver elastography:

1. Discomfort or soreness: Some patients may experience temporary discomfort or soreness in the area where the applicator or transducer was applied after the procedure. This usually goes away within a short time.
2. Allergic reaction to gel: The gel used for the procedure may cause an allergic reaction in some patients. However, this is very rare.
3. Incorrect reading of results: Interpretation of elastography results may depend on the operator's experience and the quality of the equipment. Incorrect interpretation may lead to incorrect diagnosis or treatment.
4. Rare complications: Although very rare, there is a theoretical risk of other complications such as bleeding or infection if a needle is used to perform elastography through the skin. However, most elastography procedures do not involve puncturing the skin.

It is important to note that liver elastography is significantly less invasive than alternative methods such as liver biopsy, and the risks of complications are much lower. If you experience any unusual symptoms or concerns following the procedure, you should contact your doctor immediately. Your doctor will be able to assess the situation and take the necessary steps to treat or correct complications if required.

Care after the procedure

After a liver elastography procedure, usually no special care is required. This procedure is minimally invasive and usually does not cause serious side effects. However, you may need some time to recover from it. Here are some recommendations for care after liver elastography:

1. Restoration of activity: After the procedure, you can return to your normal activity and daily routine. There is no need for bed rest or restriction of physical activity.
2. Food and Fluid: There are no special restrictions on food or fluid intake after the procedure. You can continue to eat and drink as usual.
3. Medications: If you have been prescribed any medications or doctor's recommendations, follow them as directed.
4. Visit your doctor: Your doctor may schedule a follow-up exam or consultation to discuss your elastography results and further treatment or follow-up.
5. Follow-up: Pay attention to your condition after the procedure. If you experience unusual symptoms such as severe pain, bleeding or swelling, contact your doctor immediately.

Usually, most patients recover from liver elastography without any serious complications. However, if you have any questions or concerns, it is always best to discuss them with your doctor who performed the procedure to get more detailed instructions and recommendations for your individual situation.