Dataset Information

Emphysema extent on computed tomography is a highly specific index in diagnosing persistent airflow limitation: a real-world study in China.

ABSTRACT:

Objective

The diagnostic value of emphysema extent in consistent air flow limitation remains controversial. Therefore, we aimed to assess the value of emphysema extent on computed tomography (CT) on the diagnosis of persistent airflow limitation. Furthermore, we developed a diagnostic criterion for further verification.

Materials and methods

We retrospectively enrolled patients who underwent chest CT and lung function test. To be specific, 671 patients were enrolled in the derivation group (Group 1.1), while 479 patients were in the internal validation group (Group 1.2). The percentage of lung volume occupied by low attenuation areas (LAA%) and the percentile of the histogram of attenuation values were calculated.

Results

In patients with persistent airflow limitation, the LAA% was higher and the percentile of the histogram of attenuation values was lower, compared with patients without persistent airflow limitation. Using LAA% with a threshold of -950 HU >1.4% as the criterion, the sensitivity was 44.3% and 47.2%, and the specificity was 95.2% and 95.7%, in Group 1.1 and Group 1.2, respectively. The specificity was influenced by the coexistence of interstitial lung disease, pneumothorax, and post-surgery, rather than the coexistence of pneumonia, nodule, or mass. Multivariable models were also developed.

Conclusion

The emphysema extent on CT is a highly specific marker in the diagnosis of persistent airflow limitation.

SUBMITTER: Cheng T

PROVIDER: S-EPMC6301435 | biostudies-literature | 2019

REPOSITORIES: biostudies-literature

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Publications

Emphysema extent on computed tomography is a highly specific index in diagnosing persistent airflow limitation: a real-world study in China.

Cheng Ting T Li Yong Y Pang Shuai S Wan Huan Ying HY Shi Guo Chao GC Cheng Qi Jian QJ Li Qing Yun QY Pan Zi Lai ZL Huang Shao Guang SG

International journal of chronic obstructive pulmonary disease 20181217

<h4>Objective</h4>The diagnostic value of emphysema extent in consistent air flow limitation remains controversial. Therefore, we aimed to assess the value of emphysema extent on computed tomography (CT) on the diagnosis of persistent airflow limitation. Furthermore, we developed a diagnostic criterion for further verification.<h4>Materials and methods</h4>We retrospectively enrolled patients who underwent chest CT and lung function test. To be specific, 671 patients were enrolled in the derivat ...[more]

PMID: 30587958

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Dataset Information

Emphysema extent on computed tomography is a highly specific index in diagnosing persistent airflow limitation: a real-world study in China.

Objective

Materials and methods

Results

Conclusion

Publications

Emphysema extent on computed tomography is a highly specific index in diagnosing persistent airflow limitation: a real-world study in China.

Similar Datasets

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