©2005 Surgical Planning Laboratory, ARR Slide 1

COPD: Phenotypes from CT analysis

Raul San Jose Estepar, Ph.D.

©2005 Surgical Planning Laboratory, ARR Slide 2

Clinical relevance

COPD is characterized by:•Airway narrowing/remodeling.•Parenchymal destruction.

Hypothesis: Improve diagnosis and therapeutic strategies by better understanding the mechanisms leading to airflow obstruction. This means that we can provide the therapy that is best suited for a given phenotype.

Goal: •Development of robust automated tool for analysis of CT chest scans.•Definition of COPD phenotypes.

©2005 Surgical Planning Laboratory, ARR Slide 3

Challenges for the Phenotype quest

Definition of lung mask

Airway analysis:•Lumen segmentation•Wall segmentation

Quantitative analysis

©2005 Surgical Planning Laboratory, ARR Slide 4

Lung mask

Lung mask extraction for a High Resolution CT scan

Definition of a lung mask is the first step of the processing pipeline.

Mask extraction allows lung mask density analysis.

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Migration of methods originally developed for brain segmentation and vascular segmentationVessel segmentation: Lorigo et al. , 2001.

Brain segmentation: Pichon et al, 2003

Airways: From the brain to the lungs

Sponsored by NAC

©2005 Surgical Planning Laboratory, ARR Slide 6

Airway centerlines

Segmented airway and extracted centerline.

Airway centerlines serve as a tree representation of the airway structure

©2005 Surgical Planning Laboratory, ARR Slide 7

Airway inspection

Focusing on the airway wall by traveling along the airway.

New CT view in planes orthogonal to the airway.

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Airway wall

Development of new methods for the segmentation of airway wall.

Challenge: wall not always visible due to occlusion with pulmonary vessels.

©2005 Surgical Planning Laboratory, ARR Slide 9

Quantitative analysis

Lung mask density.

Wall thickness.

Percentage of wall area.

Geometric measures: curvature of airway lumen.

Rate of change across airway generations.

©2005 Surgical Planning Laboratory, ARR Slide 10

Collaborators

SPL:•S. Haker, Ph.D.•C-F. Westin, Ph.D.

Channing Lab:•E. Silverman, M.D.

Pulmonary division:•G. Washko, M.D.•J.J. Reilly, M.D.