2001 Progress Report: X-ray CT-based Assessment of Variations in Human Airway Geometry: Implications for Evaluation of Particle Deposition and Dose to Different Populations

EPA Grant Number: R827351C002
Subproject: this is subproject number 002 , established and managed by the Center Director under grant R827351
(EPA does not fund or establish subprojects; EPA awards and manages the overall grant for this center).

Center: EPA NYU PM Center: Health Risks of PM Components
Center Director: N/A
Title: X-ray CT-based Assessment of Variations in Human Airway Geometry: Implications for Evaluation of Particle Deposition and Dose to Different Populations
Investigators: Cohen, Beverly S. , Hoffman, Eric
Institution: New York University School of Medicine , University of Iowa
EPA Project Officer: Chung, Serena
Project Period: June 1, 1999 through May 31, 2005 (Extended to May 31, 2006)
Project Period Covered by this Report: June 1, 2001 through May 31, 2002
RFA: Airborne Particulate Matter (PM) Centers (1999) RFA Text |  Recipients Lists
Research Category: Air Quality and Air Toxics , Particulate Matter , Air

Objective:

The main objective of this research project is to utilize the accomplishments of our original particulate matter (PM) Center project, which provided the tools for utilization and retrieval of morphometric data from three-dimensional (3-D) images of human conducting airways obtained by volumetric X-ray. The computerized data files are used to produce hollow airway casts by stereolithography (STL). The project continues the collaboration between the extensive imaging expertise at the University of Iowa with the New York University Particulate Matter Center (NYU PM Center) particle deposition expertise. The ultimate objective is to quantify the impact of the airway variability on PM deposition and dose. This current project seeks to compare inhaled particle deposition pattern and efficiency in sheep in vivo with the deposition measured in a hollow airway cast prepared from the same animal's 3-D image. We also will explore deposition for a variety of breathing patterns and when particles are inhaled at different points in the respiratory cycle. Another objective of this research project is to examine in vivo bolus deposition to validate the hypothesis that regional deposition can be predicted via a mathematical algorithm based on a progressive series of varying-depth bolus deposition measurements.

Progress Summary:

The success of the original PM Center project is demonstrated in the figures below. Figure 1 shows computed tomography (CT)-based images of an in vivo human lung and the derived cast. Derived airway measurements are compared in Figure 2.

Figure 1. CT-Based 3-D Images of Airway Lumen

Figure 2. Comparison Between CT-Based Measures of Original In Vivo Airway and the Stereolithography-Derived Replicate

Work is in progress at the NYU laboratory on the development of a monodisperse radio-opaque test aerosol and selection of parameters for the sheep inhalation experiments. Dr. Judy Xiong has joined the project as a co-investigator. She will assist Dr. Cohen with the experiments to be conducted in Iowa as well as the developmental work underway at NYU.

Future Activities:

We will quantify the impact of the airway variability on PM deposition and dose in the population. We plan to demonstrate that measurements in a CT-STL-produced cast can accurately predict in vivo deposition. This will involve:

• Comparisons of inhaled particle deposition pattern and efficiency in sheep in vivo with the deposition measured in a hollow airway cast prepared from the same animal's 3-D image.

• Exploration of particle deposition for a variety of breathing patterns and when particles are inhaled at different points in the respiratory cycle.

• Examination of in vivo bolus deposition to validate the hypothesis that regional deposition can be predicted via a mathematical algorithm based on a progressive series of varying-depth bolus deposition measurements.

Journal Articles:

No journal articles submitted with this report: View all 1 publications for this subproject

Supplemental Keywords:

particulate matter, PM, PM components, exposure, epidemiology, clinical, animal, toxicology, X-ray flourescence, XRF, measurement, ion chromatography, IC, mobile air monitoring, tapered element oscillating microbalance, TEOM, aethalometer., RFA, Health, PHYSICAL ASPECTS, Scientific Discipline, Air, ENVIRONMENTAL MANAGEMENT, particulate matter, Environmental Chemistry, Health Risk Assessment, Risk Assessments, Physical Processes, Environmental Monitoring, Atmospheric Sciences, Risk Assessment, ambient air quality, atmospheric particulate matter, particulates, air toxics, atmospheric particles, chemical characteristics, toxicology, ambient air monitoring, acute lung injury, airborne particulate matter, environmental risks, exposure, epidemelogy, air pollution, aerosol composition, atmospheric aerosol particles, human exposure, PM, X-ray tomagraphy, airway contractile properties, exposure assessment

Progress and Final Reports:

Original Abstract
  • 1999 Progress Report
  • 2000 Progress Report
  • 2002 Progress Report
  • 2003 Progress Report
  • 2004
  • Final Report

  • Main Center Abstract and Reports:

    R827351    EPA NYU PM Center: Health Risks of PM Components

    Subprojects under this Center: (EPA does not fund or establish subprojects; EPA awards and manages the overall grant for this center).
    R827351C001 Exposure Characterization Error
    R827351C002 X-ray CT-based Assessment of Variations in Human Airway Geometry: Implications for Evaluation of Particle Deposition and Dose to Different Populations
    R827351C003 Asthma Susceptibility to PM2.5
    R827351C004 Health Effects of Ambient Air PM in Controlled Human Exposures
    R827351C005 Physicochemical Parameters of Combustion Generated Atmospheres as Determinants of PM Toxicity
    R827351C006 Effects of Particle-Associated Irritants on the Cardiovascular System
    R827351C007 Role of PM-Associated Transition Metals in Exacerbating Infectious Pneumoniae in Exposed Rats
    R827351C008 Immunomodulation by PM: Role of Metal Composition and Pulmonary Phagocyte Iron Status
    R827351C009 Health Risks of Particulate Matter Components: Center Service Core
    R827351C010 Lung Hypoxia as Potential Mechanisms for PM-Induced Health Effects
    R827351C011 Urban PM2.5 Surface Chemistry and Interactions with Bronchoalveolar Lavage Fluid (BALF)
    R827351C012 Subchronic PM2.5 Exposure Study at the NYU PM Center
    R827351C013 Long Term Health Effects of Concentrated Ambient PM2.5
    R827351C014 PM Components and NYC Respiratory and Cardiovascular Morbidity
    R827351C015 Development of a Real-Time Monitoring System for Acidity and Soluble Components in Airborne Particulate Matter
    R827351C016 Automated Real-Time Ambient Fine PM Monitoring System