Airflow Modeling With Xenon Gas MRI in Children With Obstructive Sleep Apnea

AI summary

From the trial's eligibility criteria. Machine-read from the registry text on this page, so it can be wrong. The registry text below and the trial team decide who can take part.

The trial is looking for children and teens whose moderate or severe obstructive sleep apnea (breathing pauses during sleep) continues after removal of the tonsils and adenoids. They need surgery for it.

Age

3 to 18 years. For Aim 1 and the xenon gas part: 5 to 18 years. For Aims 2 and 3: 3 to 18 years.

Sex

Male or female.

Disease stage

Moderate or severe sleep apnea that continues after surgery to remove tonsils and adenoids (oAHI > 5 per hour of sleep). There must be signs or suspicion of a blocked upper airway, such as large tongue tonsils, a large tongue or a small lower jaw. The surgeon must judge that surgery for sleep apnea is needed.

Earlier treatment

Must have had tonsils and adenoids removed. Must have tried CPAP (a breathing mask machine) without success, or parents chose surgery without trying CPAP.

Biomarker or test result

oAHI > 5 per hour of sleep on a sleep study.

Main reasons for not taking part

• Children whose sleep apnea is well controlled with CPAP
• Children with braces or metal rods
• Children who cannot be given sedation (sleep medicine)
• Usual reasons a person cannot have an MRI scan, as set by the CCHMC Department of Radiology

The registry criteria, word for word

Check if you might fit

Answer for yourself. This is not a decision: only the study team can say whether you can take part.

• Are you between 3 and 18 years old?YesNo

What the trial wants to find out

To create a validated computational tool to predict surgical outcomes for pediatric patients with obstructive sleep apnea (OSA). The first line of treatment for children with OSA is to remove their tonsils and adenoids; however, these surgeries do not always cure the patient. Another treatment, continuous positive airway pressure (CPAP) is only tolerated by 50% of children. Therefore, many children undergo surgical interventions aimed at soft tissue structures surrounding the airway, such as tonsils, tongue, and soft palate, and/or the bony structures of the face. However, the success rates of these surgeries is surprisingly low. Therefore, there a need for a tool to improve the efficacy and predict which surgical option is going to benefit each individual patient most effectively. Computational fluid dynamics (CFD) simulations of respiratory airflow in the upper airways can provide this predictive tool, allowing the effects of various surgical options to be compared virtually and the option most likely to improve the patient's condition to be chosen. Previous CFD simulations have been unable to provide information about OSA as they were based on rigid geometries, or did not include neuromuscular motion, a key component in OSA. This project uses real-time magnetic resonance imaging (MRI) to provide the anatomy and motion of the airway to the CFD simulation, meaning that the exact in vivo motion is modeled for the first time. Furthermore, since the modeling is based on MRI, a modality which does not use ionizing radiation, it is suitable for longitudinal assessment of patients before and after surgical procedures. In vivo validation of these models will be achieved for the first time through comparison of CFD-based airflow velocity fields with those generated by phase-contrast MRI of inhaled hyperpolarized 129Xe gas. This research is based on data obtained from sleep MRIs achieved with the subject under sedation. While sedating the patient post-operatively is slightly more than minimal risk, the potential benefits to each patient outweigh this risk. As 58% of patients have persistent OSA postsurgery and the average trajectory of OSA severity is an increase over time, post-operative imaging and modeling can benefit the patient by identifying the changes to the airway made during surgery and which anatomy should be targeted in future treatments.

The 2 groups in the trial

• Phase 1 - Contrast 129Xe MRI ages 5-18Treatment being tested

  The research team will collect data characterizing upper airway anatomy, motion, and airflow. In patients, these data may be recorded before and after surgery. The data may include some or all of the following: (1) Static and dynamic proton MRI of the airway. (2) Respiratory airflow measurements. (3) Phase contrast MRI of inhaled gas. (4) Data from clinical PSGs. (5) Measurements may be repeated at different levels of CPAP.

  Treatment: 129-Xe

• Phase 2 - Contrast 129Xe MRI ages 3-18Treatment being tested

  The research team plans to collect data characterizing upper airway anatomy, motion, and airflow. In patients, these data may be recorded before and after surgery. The data may include some or all of the following: (1) Static and dynamic proton MRI of the airway. (2) Respiratory airflow measurements. (3) Data from clinical PSGs. (5) Measurements may be repeated at different levels of CPAP.

  Treatment: 129-Xe