• Chronic Obstructive Pulmonary Disease: Quantitative and Visual Ventilation Pattern Analysis at Xenon Ventilation CT Performed by Using a Dual-Energy Technique

    Radiology: Volume 256: Number 3—September 2010

    Chronic Obstructive Pulmonary Disease: Quantitative and Visual Ventilation Pattern Analysis at Xenon Ventilation CT Performed by Using a Dual-Energy Technique


    Eun-Ah Park, MD Jin Mo Goo, MD Sang Joon Park, BS Hyun Ju Lee, MD Chang Hyun Lee, MD Chang Min Park, MD Chul-Gyu Yoo,MD Jong Hyo Kim, PhD

    Purpose: To evaluate the potential of xenon ventilation computed tomography (CT) in the quantitative and visual analysis of chronic obstructive pulmonary disease (COPD).

    Materials and Methods: This study was approved by the institutional review board. After informed consent was obtained, 32 patients with COPD underwent CT performed before the administra­tion of xenon, two-phase xenon ventilation CT with wash-in (WI) and wash-out (WO) periods, and pulmonary func­tion testing (PFT). For quantitative analysis, results of PFT were compared with attenuation parameters from prex-enon images and xenon parameters from xenon-enhanced images in the following three areas at each phase: whole lung, lung with normal attenuation, and low-attenuating lung (LAL). For visual analysis, ventilation patterns were categorized according to the pattern of xenon attenuation in the area of structural abnormalities compared with that in the normal-looking background on a per-lobe basis: pattern A consisted of isoattenuation or high attenuation in the WI period and isoattenuation in the WO period; pattern B, isoattenuation or high attenuation in the WI period and high attenuation in the WO period; pattern C, low attenuation in both the WI and WO periods; and pat­tern D, low attenuation in the WI period and isoattenua­tion or high attenuation in the WO period.

    results: Among various attenuation and xenon parameters, xenon parameters of the LAL in the WO period showed the best inverse correlation with results of PFT (P < .0001). At vi­sual analysis, while emphysema (which affected 99 lobes) commonly showed pattern A or B, airway diseases such as obstructive bronchiolitis (n = 5) and bronchiectasis (n = 2) and areas with a mucus plug (n = 1) or centrilobular nodules (n = 5) showed pattern D or C.

    Conclusion: WI and WO xenon ventilation CT is feasible for the si­multaneous regional evaluation of structural and ventila­tion abnormalities both quantitatively and qualitatively in patients with COPD.