IP Requirements:

• CHOA IP

Experience Requirements:

• Mechanical Design

Introduction

Currently, imaging of the chest – be it a chest radiograph, computed tomography (CT) scan or magnetic resonance imaging (MRI) scan – is done with different techniques and at different lung volumes which creates significant differences in image quality and affects the comparability of results from scans obtained at each site. Specifically for patients that undergo imaging procedures at different sites, this means that their image quality varies a lot by location. To overcome this variability, I am proposing the use of a device for all chest imaging across all sites to standardize chest imaging. This device allows the subject undergoing chest imaging to hold their breath at full inspiration to ensure that their lungs are fully inflated when the images are taken. It significantly reduces the chances of missing small findings such as lung nodules that can be difficult to detect in partially inflated lungs. This device also allows the breath to be held reliably at the end of a full exhalation so that images acquired at end-expiration can adequately demonstrate localized areas of relative air trapping that is caused by small airways obstruction. By ensuring that images are acquired at the specified/desired lung volumes, it reduces the need for repeat imaging, enhances the ability to detect smaller changes that could be missed on less well inflated lungs, and allows for better comparison of repeat imaging studies performed for the same subject over time. 

Unmet Clinical Need

There is currently no commercially available device that provides this functionality for either children or adults. It can be used during chest Computed Tomography (CT) or Magnetic Resonance Imaging (MRI) scans that are done either under sedation (for young children) or with awake individuals (older children and adults). It provides the radiologist or technician performing the imaging study with real time data regarding what phase of respiration the subject is in during each phase of imaging. The use of this device is clinically important because it improves consistency between different imaging time points for the same subject, reduces artefacts caused by poor lung expansion, and enables reliable detection of air trapping and small airway obstructions that can only be seen on adequately performed expiratory imaging. This device can be used in all hospitals and outpatient radiology locations where chest imaging of any kind is performed. 

Aims/Objectives

This proposal to develop and validate the inspiratory/expiratory breath hold device has the following aims and objectives:

1. To create a full automated inspiratory-expiratory breath hold device for chest imaging in collaboration with Global Center for Medical Innovation that allows radiology teams to perform chest imaging reliably at all CHOA sites.
2. To validate the use of this device for all imaging modalities (chest x-ray, CT or MRI) and across all sites by creating specific imaging protocols
3. To train all radiology technicians and staff in the use of the inspiratory-expiratory breath hold device for chest imaging to ensure efficient delivery of care across all CHOA campuses. 

Target Population

The target population for this project will be all pediatric patients that are being evaluated for acute or chronic lung diseases through chest imaging. Its use can also be extended to adults as well. The use of inspiratory and expiratory breath hold chest imaging has been recommended in the literature for a wide variety of lung diseases, ranging from acute infections such as COVID-19 (1, 2) to chronic lung conditions such as chronic obstructive pulmonary disease (COPD) (3-6), emphysema (7), cystic fibrosis (CF) (8-11), sarcoidosis (12), airway disorders (13, 14), bronchopulmonary dysplasia (12) and primary ciliary dyskinesia (15, 16). The main advantages for inspiratory scans are the improved ability to detect changes in small to medium sized airways such as airway wall thickening, dilatation and mucus plugging. In adults that are being screened for lung cancer, there is a higher chance of missing small lung nodules if the chest CT is not performed with full inflation of the lungs. In addition, for patients with chronic lung diseases who get follow up CT scans to monitor disease progression, the comparison of previous imaging done at a different lung volume to the present imaging will make accurate assessment of disease progression and response to therapies very difficult. Some researchers have used spirometry gated CT (11) and MRI (14) scans as a way to monitor lung volumes during imaging, but this methodology is not uniformly available at all sites and radiology technicians are not trained on how to use spirometers in patients. Hence there is an unmet clinical need for a simple device that can ensure that breath holds with full inspiration and expiration can be performed reliably with minimal intervention so that adequate quality images can be obtained in all age ranges without the need to repeat it if there are too many artifacts. 

Outcomes to be measured

The main outcome measures are: 1) 100% of all chest CTs to be performed with inspiratory and expiratory breath hold technique across all ages. 2) Reducing the need for repeat imaging due to inadequate lung expansion to zero. 3) Ensuring that there are uniform imaging protocols across all CHOA sites. 

Relevance

The project is highly innovative and integrates the development of a novel device and its use in clinical care setting to provide consistent and reliable chest imaging in patients of all ages. This has the potential to be developed into a commercially available device once there is enough data generated from its use for a variety of indications in both inpatient and outpatient patient populations.