SOZO® is the world’s first, and only, interactive healthcare device specifically developed for Lymphoedema prevention and assessment.

ImpediMed’s bioimpedance spectroscopy (BIS) devices accurately and non-invasively measure a patient’s total body water, and extracellular and intracellular fluid volumes to aid in the assessment and interventions for chronic diseases.
SOZO®, the world’s most advanced, non-invasive BIS device, gives healthcare professionals a precise snapshot of fluid status and tissue composition in less than 30 seconds.


 Why Bioimpedance Spectroscopy (BIS)?
– Research grade data
– BIS detects medically meaningful fluid shifts as low as 36 ml in a limb.
– Rapid, repeatable, non-invasive testing​
Why Lymphoedema Index (L-DEX) Score?
– 81% reduction in Lymphoedema progression using BIS for early detection combined with at-home intervention.
– Internationally recognised best practice.
– Track and manage patient’s results automatically.
Clinically proven
ImpediMed pioneered the use of BIS technology, producing the first commercially available BIS devices in 1990. The patented, clinically proven BIS technology measures impedance at 256 different frequencies, from 3 kHz to 1000 kHz, and uses validated mathematical models to determine three pure resistance values in the body:
– Resistance at zero frequency = the free fluid outside of the body’s cells
– Intracellular resistance = the fluid inside the body’s cells
– Resistance at infinite frequency = the total body water including fluid inside of the body’s cells
These values form the foundation of all of the tissue and fluid output measures produced by ImpediMed’s BIS products.


Find out more about how the system works on our Health is Fluid Webinar Series
L-DEX® Measurement
– Bilateral readings for arms and legs


Tissue and Fluid analysis measuring;
– Fat mass
– Fat free mass
– Total body water
– Intracellular Fluid
– Extracellular fluid
– Hydration status


MYSOZO® Cloud based software:
– Automatically trends results
– Patient grouping
– Setting baseline measurement
– Remote data management
– Simple user interface with Android tablet

Request your online demo

Bioimpedance spectroscopy (BIS) is the only non-invasive, low-cost technology that can accurately measure a patient’s total body water, extracellular and intracellular fluid volumes in a clinical setting. This detailed data can help healthcare professionals with early detection, assessment and interventions for chronic conditions.


Lymphoedema Index (L-DEX) Score
How it works?
Using BIS technology, the ImpediMed device sends a low-level electrical signal through the body. As Lymphoedema develops, the amount of fluid will increase, making it easier for the signal to travel though the extracellular fluid of the body.
What is an L-DEX Score?
An L-DEX score is a unique measurement of fluid build-up in a limb which is at-risk of developing lymphedema compared to a healthy limb. It was developed by ImpediMed to aid in the clinical assessment of lymphedema in an arm or a leg. It is measured using ImpediMed’s SOZO Digital Health System.
The L-DEX score compares how easily the electrical signal moves through the unaffected and the affected limbs. The L-DEX score is initially displayed against a normal or healthy range, as shown below.
For patients with a baseline measurement, subsequent L-DEX scores can be compared to their baseline for an even more personalised assessment. At-risk patients receive a baseline measurement before treatment and then are measured regularly after treatment. An L-DEX increase of 6.5 or more is an indication that lymphedema is developing, and intervention is needed.


Extensively researched
ImpediMed’s BIS technology has been studied in more than 500 peer-reviewed, published articles and over 40 different disease states or medical conditions.
These studies have demonstrated the utility of BIS in monitoring fluid status and tissue composition for multiple purposes including the management of chronic diseases.
– Shah 2020 – The Impact Of Lymphoedema Monitoring Techniques
– Cornish et. al. (2001) Early Diagnosis of Lymphedema using multiple frequency bioimpedence
– Soran et. al. 2014 – The Importance of Detection of Subclinical LE for the Prevention of BCRL after ALND
– Smoot et. al. 2010 – Comparison of diagnostic accuracy of clinical of BCRL
– Stout et. al. 2011 – BCRL Comparing Cost Prospective Model vs Traditional
– Yang et. Al. 2016 – Use of prospective surveillance to prevent BCRL
– Shah et. Al. 2016 – Systematic Review of early detection of Lymphoedema
Taking a Measurement
– Patient removes shoes and socks, any jewellery and metallic objects on their person inc. watches and mobile devices.
– The clinician selects MEASURE. From here the patient stands still whilst the device sends the 256 frequencies through the patient.
– The measurement process takes approximately 30 seconds



Tablet – Samsung Galaxy Tab® A:
10.1 in / 25.7 cm WUXGA (1920 X 1200) TFT LCD 1.6 GHz Octa Core Processor 2.0 GB RAM 8.0 MP AF 7,300 mAh Battery 16 GB Memory


Weight Capacity:
375 lb / 170 kg


Technical Specifications:
Bluetooth®, Wi-Fi® Power: 24 V DC, 1A power supply


SOZO Device: 10.0 lb / 4.5 kg
SOZOsupport Stand: 25.5 lb / 11.6 kg


SOZOtouch: 13.0 x 6.8 x 2.9 in / 33.0 x 17.2 x 7.4 cm
SOZOstep: 17.4 x 12.7 x 2.2 in / 44.2 x 32.3x 5.7 cm
SOZOsupport Stand (with plates): 17.5 x 18.4 x 41.5 in / 44.5 x 46.7 x 105.4 cm


Sensors:  8 stainless steel electrodes
Frequency Scan: 3 to 1000 kHz (256 frequencies)
Measurement Speed: 20 seconds for 256 frequencies


Questions about L-DEX
How do I know if an L-DEX Score is normal/abnormal?
The normal range for an L-DEX score is between -10 and +10. A value greater than +10, or a value which has increased more than 6.5 units from a baseline measurement, indicates an accumulation of excess fluid outside the cells in the at-risk limb which can indicate Lymphoedema. The healthcare professional should consider the patient history when interpreting the L-DEX values and use the score as an aid in their clinical assessment of Lymphoedema.


How does the L-DEX Score aid in the prevention of cancer-related lymphedema?
Like many medical conditions, secondary, cancer-related Lymphoedema develops in stages and if caught early, progression can be prevented.
At Stage 0, lymphedema is typically reversible. The lymphatic system is impaired but there is not enough fluid build-up for patients to notice symptoms. At Stage 1, fluid accumulation usually results in noticeable swelling and discomfort. Treatment at this stage can alleviate symptoms and sometimes reverse progression. At Stages 2 and 3, Lymphoedema is irreversible. In order to prevent Lymphoedema, it must be identified and treated at an early stage.
The L-DEX score is capable of detecting Lymphoedema at the subclinical stage, when it is still reversible. If subclinical Lymphoedema is detected, patients will be instructed on at-home therapy using standard compression garments.


Are there any patient brochures that will help me explain the L-DEX Score?
Yes, we offer the SOZO Patient Information Guide and a What You Should Know About Lymphoedema and Cancer brochure free of charge to customers.


Please contact us to obtain these brochures.


How does an L-DEX score improve on the tape measure or volumetric bath?
The L-DEX score is an objective and validated metric for Lymphoedema assessment worldwide, and has excellent repeatability. Tape measure and water displacement measurements are subject to user variability. Unlike L-DEX, tape measure and water displacement measurements are not specific to fluid changes and are impacted by changes in muscle or fat.


Why does the L-DEX score go down in a patient who has visible Lymphoedema and fibrotic changes?
An L-DEX score is a unique measurement of fluid build-up in a limb which is at-risk of developing Lymphoedema compared to a healthy limb. It will monitor increases or decreases in the fluid in fibrotic limbs. In patients with advanced cases of fibrosis where there is little excess fluid, the L-DEX result may not correspond to the physical size of the arm or leg.
Technical FAQs


Will I get a tablet with my purchase of a SOZO device?
Yes, a tablet will be provided. The SOZOapp (application) will be pre-loaded on the tablet.


Do I need to update my SOZOapp?
Customers will be notified of SOZOapp updates when they are available. ImpediMed technical support can help complete the updates if needed.


Does the tablet support Mobile Device Management (MDM)?
Yes, the SOZO tablet and SOZOapp support typical MDM systems for securing the devices.
Where does SOZO store data?
All data are stored on secured infrastructure hosted by ImpediMed through Amazon Web Services. No data are stored in the tablet (SOZOapp) or the SOZO device itself.


Does SOZO encrypt data?
All data sent between SOZOapp and and all data at rest are encrypted using SSL/HTTPS. All data sent between SOZOapp and the SOZO device are encrypted using standard Bluetooth® encryption.


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Get in touch Call +44 (0)161 713 0409 or email us