XL+ Probe

Expand your diagnosis and measure more patients with the XL probe. On obese patients, biopsy is often difficult to recommend and fibrosis blood markers may be inefficient. (XL + is the third generation version of the XL probe.)


Echosens extends the limits of the existing FibroScan® 502 to obese patients with the new XL probe* which:

  • Improves the use of FibroScan® on obese patients thanks to a new 2.5 MHz ultrasonic transducer and a new electrodynamic transducer (vibrator)
  • Performs deeper measurements, between a depth of 35 and 75 mm, with an adapted algorithm

Obesity:  a major public health problem

Today, the global epidemic of obesity – “globesity1” – is becoming a major public health problem in many parts of the world.

More than 1.1 billion people are estimated to be overweight worldwide. Around 320 millions of them are now considered obese.

The increasing prevalence of overweight and obese individuals is associated  with many diet-related chronic diseases including:

  • Diabetes
  • Cardiovascular diseases
  • Hypertension
  • Some cancers


Until now, as reported in several studies, the performance of the FibroScan® 502 was limited in overweight people (from and above 25-28kg/m²)2 resulting in a difficult, or even impossible examination of these patients.

Indeed, measurements with FibroScan® may fail on obese patients for several reasons.

Because of the fat and connective tissue thickness:

  • Shear waves may not propagate properly though the liver and ultrasound signals can become attenuated and aberrated: No or fewer signals leads to no result
  • Distance between the skin and liver is too large so measurement may partly be performed outside of the liver which will lead to biased results

2.Foucher, J., L. Castera, et al. (2006). Prevalence and factors associated with failure of liver stiffness measurement using FibroScan® in a prospective study of 2114 examinations. European Journal of Gastroenterology & Hepatology 18(4): 411-2.


The XL Probe is a complete software, hardware and training package of innovation & optimization which includes:

A new Probe (XL) with:
  • A new design improving operator comfort (lighter and more ergonomic)
  • A new more sensitive ultrasonic transducer at a low frequency of 2.5 MHz adapted to enhance signal penetration deeper into liver tissues
  • A new electrodynamic transducer (vibrator) to increase vibration shot amplitude in order to take into account connective tissue thickness between the skin and liver
New Software with new features:
  • XL probe parameters are automatically set up after probe selection
  • An optimized calculation algorithm allows stiffness measurement at a deeper depth (between 35 and 75 mm)
An Ultrasound Scanner For:
  • Liver localization to help choose the optimal measurement point and ensure the performance of the examination into the liver
  • Skin Capsula Distance (SCD) measurement to choose the appropriate probe according to the Echosens recommendations(a minimum of 25 mm SCD is mandatory to use the XL Probe)
New dedicated training including:
80x80 ruban10
  • A specific theoretical session to learn concepts of Transient Elastography on obese people and understand indications & criteria of use of the XL probe
  • A practical session to teach good examination practice with the XL probe and to know how to use the ultrasound scanner to perform a liver localization and Skin Capsula Distance measurement

• User shall hold the probe perpendicular to the probe/skin (XL Probe does not improve perpendicularity)
• Using the XL Probe on patients with a SCD < 2.5 cm will lead to false results (biased estimation)
• FibroScan® examination will be difficult on patients known as being difficult to examine with an ultrasound scanner
• Examination on obese patients can be difficult and longer even with the XL probe
• Operators must take time to perform an examination


Expand your diagnosis with our new specific product for a better clinical assessment.

Before each liver stiffness examination, for optimal performance with the XL Probe, Echosens recommends performing a localization of the liver and assessing the Skin Capsular Distance (SCD).

Skin Capsula Distance (SCD)

The SCD is the key parameter because liver stiffness measurements start at a fixed depth depending on the probe type chosen. SCD represents the distance between the point of application on the skin of the transducer and the hepatic capsula. This parameter is not readily available from patients, so Echosens provides an ultrasound scanner.

The XL Probe must be used for patients with the following morphology:

2,5 cm ≤ SKin Capsula Distance < 3,5 cm

Thoracic Perimeter (TP)

The TP is generally correlated with thoracic subcutaneous thickness. It can therefore be used as a substitute criterion if Skin Capsular Distance is not available and if the thoracic perimeter exceeds 110 cm.

Even though BMI indicates if someone is obese, it is not a reliable criterion for the use of the XL probe because it is not indicative of the fat localization. For example, the XL probe makes possible measuring patients with a BMI of 60 if the SCD is less than 35mm.

Benefits of the XL Probe

For the physician, it’s a unique opportunity to:
  • Operate with the same device and enhance their initial investment
  • Leverage their manipulation and interpretation experience on the FibroScan®
  • Enlarge their diagnosis capacity and their patient work flow
For obese patients, it’s a way to :
  • Access to a safe examination with non invasive technology
  • Avoid the risk, pain and fear of biopsy
  • Have less stress, more comfort and immediate results

Technical Information

probeProbe Size
(L x Diameter)
WeightTransducer DiameterFrequencydepth of measurements
XL158x52mm0.5Kg10mm2.5Hz35mm to 75mm

New FibroScan® probe for obese patients : a pilot of feasability and performances

V. de Lédinghen1, C. Fournier2, J. Foucher1, V. Miette2, V. Rigalleau1, J. Vergniol1, W. Merrouche1, L. Sandrin2 1.Centre d’Investigation de la Fibrose hépatique, Hôpital du Haut l’Evèque, Pessac, France 2.Echosens, Paris, France

XL Probe - Clinical Trial

Studied Population

  • 99 patients with BMI > 30kg/m²


  • Measure patients with both M and XL probes


  • Assess the added value of the XL probe compared to the M Probe


  • 53 patients were successfully measured with M probe (5 valid measurements)
  • 46 patients were not measured with M probe


  • XL Probe allowed 32 additional patients to be measured (+70%)
  • The highest BMI was 61 kg/m²