Introduction
With the CE certification of Simq OSA, the innovative instrument to support the diagnosis of obstructive sleep apnea (OSA), Simq has reached another important milestone. This certification marks a major achievement for Simq and promises to enhance the accuracy and reliability of sleep apnea diagnoses, offering new hope for millions of patients worldwide. Simq approaches this medical issue with the concept of personalized medicine and medical simulation. In this blog post, we will deep-dive into the Simq OSA software and will showcase why it is a CE certified medical software.
Understanding Sleep Apnea
What is Sleep Apnea?
Sleep apnea is a disorder characterized by repeated interruptions in breathing during sleep. Obstructive sleep apnea (OSA) is the most common form caused by a physical airway blockage. Obstructive sleep apnea syndrome (OSAS) is a more severe form, often accompanied by chronic fatigue and excessive daytime sleepiness.
Symptoms and Causes
Common symptoms of OSA include loud snoring, gasping for air during sleep, morning headaches, and difficulty staying asleep. The primary causes of OSA are obesity, anatomical factors such as a thick neck or narrow airway, and lifestyle influences like smoking and alcohol consumption.
Impact of Sleep Apnea
OSA can lead to severe health complications if left untreated. These include hypertension, heart disease, stroke, diabetes, and reduced quality of life due to chronic fatigue. It is a prevalent condition, affecting an estimated 900 million adults globally.
Why CFD Simulations in Medicine?
Computational Fluid Dynamics (CFD) is a field of study that uses numerical analysis and algorithms to solve problems involving fluid flows. CFD has broad applications across various fields, including aerospace, automotive, and medical industries. In medicine, it helps understand complex fluid behaviours within the body, such as blood flow in arteries or airflow in the respiratory system.
CFD simulations offer numerous benefits in medicine, including enhanced diagnostic capabilities, improved medical device design, personalized treatment planning, and minimally invasive assessment methods. Simulations in general also play a crucial role in medical device design and research and development.
As these techniques continue to evolve and translate into clinical practice, they promise to usher in a new era of personalized and predictive medicine.
Figure 2: Visualization of the results of a CFD simulation of the airways.
CFD in Simq OSA
Simq OSA leverages CFD to create detailed, patient-specific simulations of the upper airway. Simulating airflow helps identify the anatomical causes of OSA, providing a visual and quantitative analysis that supports more accurate diagnoses and effective treatment planning. Clinicians can easily apply Simq OSA without deep CFD knowledge.
Diagnosis Enhancement
Simq OSA supports the diagnostic process through numerical simulation. It starts by creating a numerical model of the patient’s upper airway and then simulates the airflow using advanced computational methods. The simulation provides an objective assessment of the fluid mechanics parameters and helps to identify possible anatomical causes of airway obstruction.
Accuracy and Objectivity
Sleep apnea can have many causes and is a very complex topic. The use of CFD in Simq OSA significantly improves the accuracy and further diagnosis of OSA. Conventional diagnostic methods such as polysomnography provide limited or no information about the anatomical causes of airway obstruction. Simq OSA closes this gap by providing a detailed, visual representation of the patient’s airway, enabling precise diagnosis and targeted treatment.
Therapeutic Support
In addition to diagnosis, Simq OSA is also intended to support therapeutic decisions in the future by evaluating various treatment options. Several projects are already underway with renowned research partners and university hospitals to further develop Simq OSA. The goal is, for example, to simulate the effects of various interventions, such as mandibular advancement devices (MAD) or surgical procedures, and thus help doctors to select the most effective therapy for each patient.
How OSA Diagnostics Take Place with Simq Software
Here is how easy it is to apply the user-friendly Simq OSA workflow in more detail:
1. Import DICOM
The Simq OSA workflow is initiated by importing DICOM data. DICOM (Digital Imaging and Communications in Medicine) is the standard for handling, storing, printing, and transmitting information in medical imaging. This step is crucial as it is the foundation for the patient-specific simulation and the simulation model is built on the DICOM data.
Figure 3: Step 1 – DICOM data import step in the workflow.
2. Landmarks Identification
Following the import of DICOM data, the next step involves identifying and marking anatomical landmarks. These landmarks are specific points in the patient’s anatomy critical for precise simulation and assessment. By accurately marking these points, the system can ensure that the simulations align correctly with the patient’s unique anatomical features.
Figure 4: Step 2 – Identification of the landmarks in the DICOM data.
3. Breathing Cycle Definition
In the third step, the patient’s breathing cycle is defined. The breathing cycle data is crucial for creating realistic simulations that mimic the patient’s breathing and enable more precise diagnostic and therapeutic findings. Here, either a generically generated breathing cycle or, for example, data from a spirometry test can be used.
Figure 5: Step 3 – Defining the patient’s breathing cycle.
4. Simulation Process
The core of the Simq OSA workflow is the Computational Fluid Dynamics (CFD) simulation. This step employs advanced CFD techniques to model and analyze the airflow through the patient’s airway. The simulation provides a detailed view of how air moves. It interacts with the anatomical structures during breathing, which is crucial for understanding the causes and potential treatments for sleep apnea. After the configuration is complete, the simulation is sent to the cloud computing infrastructure.
5. Results Analysis
Once the simulation is completed, the user is notified to start the final step, which involves analyzing and interpreting the simulation results. The data generated from the CFD simulations are meticulously examined to provide comprehensive insights into the patient’s condition. This analysis helps identify the anatomical causes of obstructive sleep apnea and aids in selecting the most appropriate treatment options. The detailed visualizations produced during this step further enhance the understanding of the patient’s airway dynamics.
The 3D simulation is presented to the user as easy-to-interpret colored 2D projections. In the initial analysis, the medical expert can assess the patient’s condition by using the automatically determined Pharyngeal Resistance Index (PRI). This index measures the resistance to airflow in the pharyngeal airway, which is crucial for understanding the severity and mechanics of airway obstruction during sleep.
By accurately evaluating the PRI, clinicians can gain deeper insights into the specific anatomical and functional issues leading to the patient’s OSA, enabling more precise and effective treatment planning. The PRI ranges from 0 to 10, with higher values indicating a more pronounced indication of Obstructive Sleep Apnea (OSA) or Sleep-Related Breathing Disorders (SRBD).
A 3D diagram, incorporating the DICOM image, illustrates the distribution of the PRI within the patient’s pharynx. In addition to the overall PRI value, three additional values represent the PRI’s division into three specific regions of the pharynx: the velopharynx, oropharynx, and hypopharynx. The Pharyngeal Map provides a spatial and temporal evaluation of the pharynx’s condition, offering a comprehensive overview of how airflow resistance is distributed and varies over time within the different pharynx regions. This detailed mapping is crucial for accurately diagnosing and understanding the severity of OSA in patients.
Figure 6: Step 5.1 – Analysis of the Pharyngeal Resistance Index (PRI)
The Pressure Results show air pressure in the pharynx. Negative pressure is in red, while positive pressure is in blue. Underpressure can narrow the airway, while overpressure can expand it. High negative pressure values suggest a tendency towards obstructive sleep apnea (OSA).
Figure 7: Step 5.2 – Analysis of the air pressure in the pharynx.
The Velocity Results illustrate the speeds of the airflow within the pharynx, as in Figure 6. These speeds are represented as color-coded streamlines of massless air particles. Red areas indicate high velocities of the air particles. Blue Areas indicate low velocities.
High airflow velocities, especially when combined with low-pressure conditions and regions of strong turbulence, are conducive to anatomically induced obstructive sleep apnea (OSA). These conditions highlight areas where the airway is prone to collapse due to the dynamic forces at play.
Figure 8: Step 5.3 – Analysis of the airflow velocity in the pharynx.
The Geometry Results present the cross-sectional area of the pharynx in the relevant region. Red areas indicate small cross-sectional areas while blue areas indicate larger cross-sectional areas.
Small cross-sectional areas are conducive to anatomically induced obstructive sleep apnea (OSA), as they highlight regions where the airway is more likely to become obstructed due to reduced space for airflow.
Figure 9: Step 5.4 – Analysis of the pharynx geometry.
Conclusion
The certification of Simq OSA will fundamentally and sustainably change the diagnosis and treatment of sleep apnea. The integration of advanced CFD simulations into medicine points to a new era in medical diagnostics. Simq OSA provides an objective approach to the diagnosis of OSA and enables more precise and personalized treatment.
Beyond sleep apnea, these technologies have the potential to completely transform the diagnosis and treatment of various medical conditions.
Contact us today to schedule your free Simq OSA live demo!
