. Author manuscript; available in PMC: 2011 Dec 1.

Published in final edited form as: J Magn Reson Imaging. 2010 Dec;32(6):1398–1408. doi: 10.1002/jmri.22375

Table 1.

Strengths and Challenges of HRCT and HP ³He MRI for Pulmonary Functional Imaging

	Feasibility		Measurements	Phenotyping
	Strengths	Challenges	Measurements	Strengths	Challenges
MDCT	Excellent general availability, cost- effective, easy to implement	Radiation dose requirements for high resolution scans limits longitudinal series and numbers of scans	Mean lung attenuation in HU (LA) Lung attenuation% (LA%) Airway wall area as % of the total size of the airway (WA%)	High spatial resolution	Specialized software required for quantification of airway thickening
HP ³He MRI	Current availability of hardware limited to specialized MR centers; ³He quantities limited globally	Lower spatial resolution than MDCT	Apparent diffusion coefficient (ADC) Ventilation defect volume cm³ (VDV) Ventilation defect score (VDS) Percent ventilated volume (PVV) Ventilation defect volume % (VDV%)	Independent measurements of emphysema and airway occlusion, high sensitivity, excellent precision	Specialized software for quantitative phenotypes, expert observer/measurement technicians required