A four-dimensional computed tomography comparison of healthy and asthmatic human lungs

JOURNAL OF BIOMECHANICS

卷:56

Article

Jahani, Nariman^1,2,3  Choi, Sanghun⁴  Choi, Jiwoong^1,2  Haghighi, Babak^1,2  Hoffman, Eric A.^5,6,7  Comellas, Alejandro P.⁶  Kline, Joel N.⁶  Lin, Ching-Long^1,2 

[1] Univ Iowa, Dept Mech & Ind Engn, Iowa City, IA USA

[2] Univ Iowa, IIHR Hydrosci & Engn, Iowa City, IA USA

[3] Univ Penn, Dept Radiol, Perelman Sch Med, Philadelphia, PA 19104 USA

[4] Kyungpook Natl Univ, Dept Mech Engn, Daegu, South Korea

[5] Univ Iowa, Dept Biomed Engn, Iowa City, IA 52242 USA

[6] Univ Iowa, Dept Internal Med, Iowa City, IA 52242 USA

[7] Univ Iowa, Dept Radiol, Iowa City, IA 52242 USA

关键词: Four-dimensional computed tomography;    Asthma;    Ventilation heterogeneity;    Hysteresis;    Image registration;   

DOI  :  10.1016/j.jbiomech.2017.03.012

来源: Elsevier

【 摘 要 】

The purpose of this study was to explore new insights in non-linearity, hysteresis and ventilation heterogeneity of asthmatic human lungs using four-dimensional computed tomography (4D-CT) image data acquired during tidal breathing. Volumetric image data were acquired for 5 non-severe and one severe asthmatic volunteers. Besides 4D-CT image data, function residual capacity and total lung capacity image data during breath-hold were acquired for comparison with dynamic scans. Quantitative results were compared with the previously reported analysis of five healthy human lungs. Using an image registration technique, local variables such as regional ventilation and anisotropic deformation index (ADI) were estimated. Regional ventilation characteristics of non-severe asthmatic subjects were similar to those of healthy subjects, but different from the severe asthmatic subject. Lobar airflow fractions were also well correlated between static and dynamic scans (R-2 > 0.84). However, local ventilation heterogeneity significantly increased during tidal breathing in both healthy and asthmatic subjects relative to that of breath hold perhaps because of airway resistance present only in dynamic breathing. ADI was used to quantify non-linearity and hysteresis of lung motion during tidal breathing. Non-linearity was greater on inhalation than exhalation among all subjects. However, exhalation non-linearity among asthmatic subjects was greater than healthy subjects and the difference diminished during inhalation. An increase of non linearity during exhalation in asthmatic subjects accounted for lower hysteresis relative to that of healthy ones. Thus, assessment of non-linearity differences between healthy and asthmatic lungs during exhalation may provide quantitative metrics for subject identification and outcome assessment of new interventions. (C) 2017 Elsevier Ltd. All rights reserved.

【 授权许可】

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