@article {450421,
	title = {Computed tomographic measures of pulmonary vascular morphology in smokers and their clinical implications},
	journal = {Am J Respir Crit Care Med},
	volume = {188},
	number = {2},
	year = {2013},
	month = {2013 Jul 15},
	pages = {231-9},
	abstract = {RATIONALE: Angiographic investigation suggests that pulmonary vascular remodeling in smokers is characterized by distal pruning of the blood vessels.

OBJECTIVES: Using volumetric computed tomography scans of the chest we sought to quantitatively evaluate this process and assess its clinical associations.

METHODS: Pulmonary vessels were automatically identified, segmented, and measured. Total blood vessel volume (TBV) and the aggregate vessel volume for vessels less than 5 mm(2) (BV5) were calculated for all lobes. The lobe-specific BV5 measures were normalized to the TBV of that lobe and the nonvascular tissue volume (BV5/T(issue)V) to calculate lobe-specific BV5/TBV and BV5/T(issue)V ratios. Densitometric measures of emphysema were obtained using a Hounsfield unit threshold of -950 (\%LAA-950). Measures of chronic obstructive pulmonary disease severity included single breath measures of diffusing capacity of carbon monoxide, oxygen saturation, the 6-minute-walk distance, St George{\textquoteright}s Respiratory Questionnaire total score (SGRQ), and the body mass index, airflow obstruction, dyspnea, and exercise capacity (BODE) index.

MEASUREMENTS AND MAIN RESULTS: The \%LAA-950 was inversely related to all calculated vascular ratios. In multivariate models including age, sex, and \%LAA-950, lobe-specific measurements of BV5/TBV were directly related to resting oxygen saturation and inversely associated with both the SGRQ and BODE scores. In similar multivariate adjustment lobe-specific BV5/T(issue)V ratios were inversely related to resting oxygen saturation, diffusing capacity of carbon monoxide, 6-minute-walk distance, and directly related to the SGRQ and BODE.

CONCLUSIONS: Smoking-related chronic obstructive pulmonary disease is characterized by distal pruning of the small blood vessels (,
	keywords = {Aged, Angiography, Blood Vessels, Body Mass Index, Female, Humans, Lung, Male, Middle Aged, Multivariate Analysis, Pulmonary Diffusing Capacity, Severity of Illness Index, Smoking, Tomography, X-Ray Computed},
	issn = {1535-4970},
	doi = {10.1164/rccm.201301-0162OC},
	author = {San Jos{\'e} Est{\'e}par, Ra{\'u}l and Kinney, Gregory L and Black-Shinn, Jennifer L and Bowler, Russell P and Kindlmann, Gordon L and Ross, James C and Kikinis, Ron and Han, MeiLan K and Come, Carolyn E and Diaz, Alejandro A and Cho, Michael H and Hersh, Craig P and Schroeder, Joyce D and Reilly, John J and Lynch, David A and Crapo, James D and Wells, J Michael and Dransfield, Mark T and Hokanson, John E and Washko, George R}
}