Technology & Science

A New Era in Respiratory Testing

From Lab-Based to Handheld

Traditional methods for assessing lung function – such as Body Plethysmography and Nitrogen Washout – have long been the standard in respiratory diagnostics. However, they require large,
complex equipment, dedicated testing rooms, and lengthy procedures that are often uncomfortable for patients and inconvenient for clinics. While clinically effective, these systems are not always
practical for routine or widespread use

Innovative Approach to Pulmonary Diagnostics

Immediate patient condition analysis

The STS device leverages an innovative sensing method combined with an advanced AI algorithm to deliver immediate, on-screen graphical analysis of the patient’s pulmonary condition

Next generations of STS will include Artificial Intelligence (AI) features:

Restrictive Patient

Obstructive Patient

Healthy Patient

Technology Comparison

Lung volume measurement can be performed using various technologies, including body plethysmography, which assesses thoracic gas volume by measuring pressure changes in a sealed chamber, and spirometry, which estimates lung volumes based on airflow during forced breathing maneuvers. Additional methods include gas dilution techniques (like helium or nitrogen washout)

Want to learn more about the science behind STS?

Keep informed with exclusive content

Get expert insights, clinical updates, and professional opportunities—tailored for you.

Become part of our professional community

Nitrogen Washout is a traditional method used to estimate lung volumes, particularly Functional Residual Capacity (FRC), Residual Volume (RV), and Total Lung Capacity (TLC). It is based on a gas dilution principle, where the amount of nitrogen exhaled is used to calculate the volume of air remaining in the lungs after a normal breath

  • The patient breathes 100% oxygen to flush out nitrogen from the lungs
    Exhaled nitrogen is tracked until levels drop below 2%, and lung volume is calculated based on the total nitrogen exhaled
  • The Nitrogen Washout method takes up to 10 minutes and requires steady breathing and a proper seal
  • The Nitrogen Washout method requires specialized equipment and trained staff and is not ideal for oxygen-dependent patients

Body plethysmography is a standard method used to measure static lung volumes, particularly Total Lung Capacity (TLC) and Residual Volume (RV)

  • The patient sits in a sealed, airtight chamber (also called a body box) and breathes through a mouthpiece
  • As the patient breathes against a closed shutter, changes in pressure inside the box and the lungs are measured, applying Boyle’s Law to calculate lung volumes
  • While accurate, the method is time-consuming, uncomfortable, and requires a dedicated lab setup and trained technicians. Some patients—especially the elderly, claustrophobic, or pediatric—may find the enclosed space distressing

The patented dynamic process technology behind the STS (Spiro-Test System) introduces a new way to measure lung function by applying the first law of thermodynamics to real-time respiratory flow.

Unlike traditional methods such as body plethysmography, which rely on static gas laws and require enclosed chambers, or nitrogen washout, which uses gas dilution techniques and specialized gases, the STS captures and analyzes the dynamic relationship between airflow, pressure, and energy change during a natural exhalation.

As the patient exhales through a custom-designed flow system, internal sensors measure pressure and airflow under changing resistance. This data is processed by a proprietary algorithm that calculates lung volumes, airway resistance, and lung compliance—accurately and efficiently—without the need for a body box or gas-based systems. The result is a fast, non-invasive, and clinically reliable test that fits in a handheld device, making advanced respiratory diagnostics accessible in any setting

Skip to content