US ELASTOGRAPHY

Think of US Elastography as a sophisticated, high-tech version of a physical exam. When a doctor manually presses on an area of your body, they are feeling for hardness or lumps, which can be signs of a problem. Elastography does the same thing, but on a microscopic and highly precise level from inside your body.

The technology works by using low-frequency sound waves in combination with a standard ultrasound. These sound waves gently vibrate the tissue, and the ultrasound machine measures how quickly these vibrations move.

• Soft, healthy tissue allows the waves to travel slowly.
• Stiff, dense tissue (which may be caused by scarring or a tumor) causes the waves to travel much faster.

This data is then converted into a visual map, called an elastogram, which is often displayed as a color-coded overlay on the traditional black-and-white ultrasound image. This map gives the radiologist a clear picture of tissue stiffness, providing quantitative data that helps in diagnosing and monitoring various conditions.

FibroScan vs Elastography: What's the Difference?

This is a very common question. It's helpful to think of it like this: "Ultrasound Elastography" is the name of the overall technology, while "FibroScan" is the brand name for a specific type of device.

• FibroScan (Transient Elastography): This is a standalone machine dedicated solely to measuring liver stiffness. It uses a probe that sends a mechanical pulse to generate the shear waves. It provides a stiffness number but does not produce an anatomical image of the liver.
• US Elastography (Shear Wave Elastography): This technology is typically integrated directly into modern ultrasound machines at facilities like Cadabam's Diagnostics. The major advantage is that it performs two functions at once: it provides the standard ultrasound image (showing the liver's size, shape, and structure) and the color-coded stiffness map (elastogram). This allows the radiologist to see exactly where the stiffness measurement is being taken, avoiding blood vessels or other structures that could skew the result.

When our expert radiologists at Cadabam's Diagnostics perform and interpret a US Elastography, they are looking at several key parameters to build a comprehensive picture of your organ's health:

• Tissue Stiffness Measurement: This is the core data point, measured either in kilopascals (kPa) or shear wave speed (meters per second, m/s). A higher number indicates stiffer tissue.
• B-Mode Ultrasound Image: The conventional ultrasound image provides critical context. The radiologist assesses the liver's size, surface contour (smooth or nodular), and overall texture (echogenicity), looking for signs of fatty infiltration or other abnormalities.
• Uniformity of Stiffness: The radiologist evaluates whether the stiffness is consistent across the organ or if there are specific areas of increased hardness.
• Presence of Lesions: The combined imaging helps to identify and characterize any cysts, masses, or other lesions, with elastography helping to determine if a lesion is soft (likely benign) or hard (more suspicious).
• Reliability Metrics: The system also provides data like the Interquartile Range (IQR), which tells the radiologist how consistent and reliable the series of measurements were during the exam.

There are many compelling clinical reasons why your doctor would choose a US Elastography for your diagnostic journey.

• To Detect and Stage Liver Fibrosis: This is the primary use. The test can accurately determine the amount of scarring in the liver, from none (F0) to advanced cirrhosis (F4).
• To Avoid Invasive Biopsy: Historically, a liver biopsy was the only way to assess fibrosis. US Elastography offers a non-invasive, painless, and safe alternative for many patients.
• To Assess Fatty Liver Disease: It helps quantify the severity of non-alcoholic fatty liver disease (NAFLD) and determines if it has progressed to non-alcoholic steatohepatitis (NASH), which includes scarring.
• To Monitor Disease Progression: For patients with chronic liver conditions, regular elastography exams provide quantitative data to track whether the disease is worsening, staying stable, or improving with treatment.
• To Evaluate Suspicious Masses: It can help characterize masses in the breast or thyroid, providing extra information to guide decisions on whether a biopsy is needed.

When and Who Needs to Take a US Elastography?

Your doctor may recommend a US Elastography if they need to assess the health and stiffness of an organ, most commonly the liver.

Common indications for a liver elastography test include:

• Suspected Liver Disease: For patients showing symptoms of liver problems or with abnormal liver function tests.
• Chronic Liver Conditions: To monitor the progression of diseases like viral hepatitis (Hepatitis B or C), alcoholic liver disease, or autoimmune hepatitis.
• Non-alcoholic Fatty Liver Disease (NAFLD): To determine if fat in the liver has led to inflammation and scarring (a condition called NASH).

While the liver is the most common application, US Elastography is also a valuable tool for evaluating other areas of the body. It may be ordered to:

• Assess suspicious nodules in the thyroid gland.
• Characterize masses found in the breast.
• Evaluate the prostate or kidneys in specific clinical situations.

This test is particularly beneficial for patients with known risk factors for fibrosis or those currently undergoing treatment for a liver condition, as it helps track the effectiveness of the therapy.

Benefits of Taking the Test

Choosing to have a US Elastography offers several significant benefits for both patients and clinicians:

• Painless and Non-Invasive: There are no needles, surgery, or sedation involved. It feels just like a regular ultrasound.
• Safe: The test uses sound waves and involves no ionizing radiation.
• Provides Quantitative Data: It delivers a numerical result (e.g., in kPa), making it easy to track changes with high precision over time.
• Quick and Convenient: The entire procedure is usually completed in 15-30 minutes with minimal preparation.
• Informs Treatment Decisions: The results help your doctor make confident decisions about starting, changing, or stopping a treatment plan.
• Comprehensive Evaluation: When performed on an ultrasound machine, it combines anatomical and functional information in a single session.

Illnesses Diagnosed with Elastography Test

US Elastography is instrumental in the diagnosis, staging, and management of several conditions.

The primary focus is on liver diseases:

• Liver Fibrosis and Cirrhosis: It is the gold standard non-invasive tool for staging liver scarring from any cause.
• Chronic Hepatitis B and C: It helps determine the extent of liver damage and the need for antiviral therapy.
• Non-alcoholic Steatohepatitis (NASH): It can differentiate simple fatty liver from the more aggressive NASH, which involves fibrosis.
• Alcoholic Liver Disease: It is used to assess the degree of liver damage from long-term alcohol use.

Beyond the liver, it also helps in the assessment of:

• Thyroid Nodules: Helps differentiate between potentially benign and suspicious nodules.
• Breast Lesions: Adds another layer of information to mammography and traditional ultrasound to characterize lumps.

Preparation is simple but very important for ensuring the accuracy of the test results.

• Diet: You will be required to fast (no food or drink other than water) for 3-4 hours before a liver elastography test. Food intake can temporarily increase blood flow to the liver, which can falsely elevate stiffness measurements.
• Clothing: Wear comfortable, loose-fitting clothing that allows easy access to the area being scanned. You may be asked to change into a hospital gown.
• Medications: You can typically continue taking your prescribed medications. Inform the staff of all the medications you are currently on.
• Information: Please let the sonographer know if you have had any recent abdominal surgeries or if you have any pain in the area being examined.

Pre-requisites

• A doctor’s referral or prescription for the US Elastography is required.
• If you have had previous imaging exams like an ultrasound, CT scan, or MRI of the same area, please bring the reports with you. This allows our radiologist to make valuable comparisons.

Best Time to Take the US Elastography

The test can be performed at any time of day. The most important factor is that you strictly follow the pre-test fasting instructions. Many patients find it convenient to schedule their appointment in the morning after fasting overnight.

Eligibility

US Elastography is a safe procedure suitable for most adults and children. However, you should discuss your situation with your doctor or our staff if:

• You are pregnant.
• You have ascites (a significant amount of fluid in your abdomen).
• You have a cardiac pacemaker or other implanted electronic device.

In most cases, the test can still be performed, but these factors are important for the team to be aware of.

Procedure for Taking a US Elastography

The elastography procedure is straightforward and comfortable. Here is a step-by-step description of what to expect on the day of your test at Cadabam's Diagnostics:

1. Check-in: You will arrive at our center and check in for your appointment.
2. Preparation: You may be asked to change into a gown to allow easy access to the area being scanned.
3. Positioning: You will be asked to lie down on your back on a comfortable examination table, possibly with your right arm raised above your head for a liver scan.
4. Gel Application: A sonographer will apply a small amount of clear, water-based gel to your skin over the organ. This gel helps ensure good contact and allows the sound waves to travel smoothly from the transducer into your body.
5. Scanning: The sonographer will gently press a small, handheld device called a transducer against your skin. They will move it around to find the best window to view the organ.
6. Measurement: While capturing the standard ultrasound images, the elastography function will be activated. You won't feel anything different, but you may be asked to hold your breath for 5-10 seconds at a time while the stiffness measurements are being taken. This is repeated several times to ensure a reliable average.
7. Completion: Once enough high-quality readings have been recorded, the gel is wiped off, and the exam is complete.

The entire elastography procedure typically takes between 15 and 30 minutes. You can return to your normal activities immediately afterward.

Caution Before Taking the Test

For the most accurate results, please be sure to:

• Confirm Fasting: Double-check that you have followed the fasting instructions provided by your doctor or our staff.
• Communicate Discomfort: Inform the sonographer if you feel any pain or tenderness in the area being scanned. They can adjust their technique to ensure your comfort.
• Relax: Lying still and relaxed helps improve the quality of the images and measurements.