Preparing for Your
FibroScan

FibroScan (also called transient elastography) is a specialized ultrasound-based device. It uses two technologies simultaneously:

• Vibration-controlled transient elastography (VCTE) — sends a gentle vibration wave into the liver and measures how fast it travels. Stiffer liver tissue (from scarring) transmits the wave faster, giving a liver stiffness measurement (LSM) in kilopascals (kPa).
• Controlled Attenuation Parameter (CAP) — measures how much the ultrasound signal is absorbed by fat in the liver, giving a fat score in dB/m.

Together, these two measurements give your doctor a complete picture of both liver fat and fibrosis — in about 10 minutes, with no needles, no radiation, and no sedation.

FibroScan is most commonly ordered for patients with known or suspected metabolic-associated steatotic liver disease (MASLD) — formerly called MAFLD. Your doctor may have ordered it because:

• Your liver enzymes (ALT, AST) are elevated on blood work
• An ultrasound or CT scan showed a "bright" or "fatty" liver
• You have type 2 diabetes, obesity, or metabolic syndrome — all risk factors for fatty liver disease
• You are being evaluated before starting or while on medications that can affect the liver
• Your doctor wants to monitor progression or improvement of known fatty liver disease

Yes — fasting matters a great deal for accuracy.

Eating — especially a high-fat meal — temporarily increases liver stiffness even in a healthy liver. This can make your liver appear more fibrotic than it actually is, leading to a falsely abnormal result.

Minimum fast: 2 hours before your appointment.
Ideal fast: 3 hours or more.

Plain water is fine at any time. Medications taken with water are also fine. If you have diabetes and are concerned about fasting, please call our office to discuss — a 2–3 hour fast is safe for most diabetic patients, but we want to ensure your individual safety.

Plain black coffee or plain tea (no milk, cream, or sugar) is unlikely to affect results significantly. However, to ensure the most accurate scan possible, we recommend sticking to water only during your fasting period. If you do have a small plain black coffee, let your technician know when you arrive.

No. Avoid all alcohol for at least 24 hours before your FibroScan.

Alcohol causes temporary liver inflammation, which increases stiffness readings even in people without significant liver disease. Drinking the night before can make your liver appear far more scarred than it is, leading to unnecessary concern and potentially additional testing. If you consumed alcohol within 24 hours, let your technician know so the result can be interpreted in that context or the test rescheduled.

Yes — continue all your regular medications as usual, taken with water. Do not skip doses unless your doctor has specifically instructed you to. This includes blood pressure medications, diabetes medications (including GLP-1 agonists like semaglutide/Ozempic), thyroid medications, and cholesterol medications. Bring a list of any supplements or herbal products you take.

The procedure is simple, painless, and takes 10 to 15 minutes:

• You will lie on your back on an exam table with your right arm raised above your head.
• The technician will apply a small amount of ultrasound gel to your right side, just below the ribcage.
• A handheld probe will be placed on your skin in that area. You may feel a brief, gentle vibration — similar to a light flick — as each measurement is taken. This is completely painless.
• The device takes 10 measurements and averages them. You may be asked to hold your breath briefly during some readings.

There is no radiation, no contrast dye, no needles, and no sedation. You can drive yourself and return to normal activities immediately afterward.

Yes — the FibroScan uses different probe sizes to accommodate different body types:

• M probe — standard, used for most patients
• XL probe — used for patients with higher BMI (typically above 30) or a thicker abdominal wall, to ensure the signal reaches the liver accurately

If the M probe does not obtain reliable readings, the technician will switch to the XL probe — this is routine and not a cause for concern. Please inform the technician of your approximate weight so the correct probe can be selected from the start.

Your FibroScan report contains two separate scores:

1. Liver Stiffness Measurement (LSM) — measures fibrosis/scarring

2. CAP Score — measures liver fat content

Your doctor will interpret both scores together in context with your symptoms, blood tests, and medical history. Please do not try to self-diagnose based on numbers alone — context matters enormously.

Your report includes a reliability indicator — the interquartile range (IQR) divided by the median result as a percentage. This shows how consistent the 10 individual measurements were with each other.

• IQR/M ≤ 30% — result is considered reliable
• IQR/M > 30% — significant variability between measurements; result may be less reliable and the test may need to be repeated

High variability is most commonly caused by eating before the test. Proper fasting is the single most important step you can take to ensure a reliable result.

Not necessarily. Liver stiffness can be temporarily elevated by factors beyond fibrosis, including:

• Eating before the test (most common cause)
• Alcohol within 24 hours
• Acute liver inflammation or elevated liver enzymes
• Congestive heart failure or fluid congestion
• Recent vigorous exercise
• Cholestasis (bile duct obstruction)

This is why a single elevated FibroScan result is rarely treated as definitive on its own. Your doctor will look at the full clinical picture before drawing conclusions or recommending further action.

No — and that is what makes it valuable. A liver biopsy requires inserting a needle into the liver, is invasive, carries a small bleeding risk, and samples only a tiny portion of liver tissue. FibroScan is a non-invasive alternative that surveys a much larger area, is painless, and takes minutes. It is now the preferred first-line tool for fibrosis staging in fatty liver disease. A biopsy is typically reserved for cases where FibroScan results are borderline or the diagnosis remains uncertain.

Yes — fatty liver disease can improve significantly with lifestyle changes, and FibroScan is one of the best tools for tracking that improvement. Even modest weight loss (5–10% of body weight) can meaningfully reduce liver fat. Certain medications — including GLP-1 receptor agonists like semaglutide and the newer resmetirom (Rezdiffra) approved for MASH — can reduce both fat content and fibrosis scores.

Your doctor will typically repeat the FibroScan every 1–2 years. Seeing your scores improve over time is a meaningful sign of liver health recovery.

FibroScan uses ultrasound and is generally considered safe during pregnancy, though it is typically deferred until after delivery unless medically urgent. Please let the technician know if you are pregnant.

FibroScan does not use radiation or strong magnetic fields, so it is safe for patients with pacemakers, implantable defibrillators, or metal implants — unlike MRI. Always inform the technician of any implanted devices.

Your FibroScan scores are available immediately after the test. The technician may share the numbers with you, but interpretation and next steps come from your physician.

Depending on your results:

• Normal or mild findings: Lifestyle guidance and routine monitoring in 1–2 years
• Moderate fat or early fibrosis: Intensified lifestyle intervention, possible medication evaluation, more frequent follow-up
• Advanced fibrosis: Co-management with a hepatologist (liver specialist) and evaluation for complications of cirrhosis

If you have questions after receiving results, call our office at 832-968-7003 or message us through your patient portal.