Impact of Continuous Positive Airway Pressure on Breathing Motion Amplitude

This study involves a breathing motion assessment in healthy subjects before and after continuous positive airway pressure (CPAP) administration using MRI images.

The hypothesis for this study is that CPAP administration will significantly reduce breathing motion. This may help cancer patients who are undergoing proton radiotherapy, so they possibly will not have to hold their breath during the procedure.

Study Overview

• Status: Completed
• Conditions: Cancer
• Intervention / Treatment: Other: Continuous Positive Airway Pressure

Detailed Description

Minimally invasive techniques for tumor motion reduction that involve free-breathing patients have significant relevance in the context of radiation therapy, in particular proton radiotherapy. Tumor motion reduction has favorable implications for reduction of radiation doses to adjacent healthy organs, radiation plan robustness (accuracy/quality) and for treatment efficiency (reduction of treatment times). Using non-ionizing MRI with volunteers, the investigators will determine the extent to which continuous positive airway pressure (CPAP) reduces breathing motion (diaphragmatic excursion). The researchers will also investigate the parameter space associated with breathing motion reduction versus the amount of pressure applied, as well as timing of initiation of CPAP in relation to the imaging time point (to address whether an initial transient breathing state exists).

• Study Type: Interventional
• Enrollment (Actual): 10
• Phase: Early Phase 1

Contacts and Locations

Study Locations

• United States
  • Minnesota
    • Rochester, Minnesota, United States, 55905
      • Mayo Clinic in Rochester

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 18 years and older (Adult, Older Adult)
• Accepts Healthy Volunteers: Yes
• Genders Eligible for Study: All

Description

Inclusion Criteria:

1. Healthy adult female and males
2. Subject meets routine MRI safety criteria

Exclusion Criteria:

1. Age <18
2. Known history of chronic obstructive pulmonary disease (COPD), asthma, or other chronic pulmonary illness
3. Pregnancy
4. Any safety risk identified via MRI safety screening

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Basic Science
• Allocation: N/A
• Interventional Model: Single Group Assignment
• Masking: None (Open Label)

Number of Arms

1

Arms and Interventions

Participant Group / Arm

Intervention / Treatment

Experimental: Continuous Positive Airway Pressure; Continuous Positive Airway Pressure (CPAP) will be administered using FDA-approved equipment.

Other: Continuous Positive Airway Pressure; CPAP requires subjects to wear a plastic pressurized mask/apparatus, which is connected via a filter and hose to a pump capable of supplying variable pressure (typically on the range of 4-20 cm H2O). The investigators plan to use a full-face mask to prevent subjects from reducing pressure by opening their mouths. If this cannot be tolerated or properly fitted, or is not compatible with the CPAP ventilator, subjects would use a nasal mask only and be asked to keep their mouths closed.

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Change in Breathing Motion Characteristics at High CPAP Setting	Breathing motion at baseline and at initial (higher but tolerable) CPAP settings will be characterized using fast multi-slice, multi-phase 2D gradient-echo or spin-echo MRI sequences in the sagittal or coronal imaging planes over a large field of view covering the thoracic and upper-abdominal region. Specifically "4D-MRI" (or time-resolved MRI) will be generated from retrospective sorting of multi-slice 2D MRI. For these analyses, anatomic reference points (e.g., bright vessels) in multiple organ systems will be identified on the images, contoured or segmented; subsequently 3D motion patterns will be extracted for all anatomical references/features. Numerical simulations will be performed to determine hypothetical radiation target volume changes (cm^3) at these anatomic locations assuming spherical tumors with a given set of tumor diameters (cm).	Data acquisition for this portion of the study will require approximately 30 minutes.

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Change in Breathing Motion Characteristics at Lower CPAP Setting	Time permitting, the CPAP setting will be reduced to approximately half of the nominal/tolerable/high CPAP setting. Using the same MRI sequences and retrospective sorting technique, 4D-MRI will be generated for this lower CPAP setting. Analogous motion characterization analyses (to outcome measure 1) will be carried out for the lower CPAP setting (relative to baseline 4D-MRI).	Approximately 45 minutes into visit.

Collaborators and Investigators

• Sponsor: Mayo Clinic
• Investigators: Principal Investigator: Erik J Tryggestad, PhD, Mayo Clinic

Study record dates

Study Major Dates

• Study Start: July 1, 2016
• Primary Completion (Actual): September 1, 2016
• Study Completion (Actual): September 1, 2016

Study Registration Dates

• First Submitted: June 3, 2016
• First Submitted That Met QC Criteria: July 28, 2016
• First Posted (Estimate): August 2, 2016

Study Record Updates

• Last Update Posted (Estimate): October 14, 2016
• Last Update Submitted That Met QC Criteria: October 13, 2016
• Last Verified: October 1, 2016

More Information

Terms related to this study

• Keywords: Continuous Positive Airway Pressure; Radiotherapy; Proton Therapy
• Other Study ID Numbers: 16-001685

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: UNDECIDED