J Korean Radiol Soc.  1996 Aug;35(2):189-193.

Measurement of Total Lung Capacity: A Comparison of Spiral CT and Spirometry

• Chung KI
• Park KJ
• Lee EH
• Choe KO
• Lim TH
• Chung IH
• Yune HY
• Suh JH

Abstract

PURPOSE
To determine the potential of spiral CT as a functional imaging modality of the lung asid from its proven value in morphological depiction.
MATERIALS AND METHODS
Spiral CT scan was performed in ten normal female and nine normal male adults (mean age: 39, height: 163cm, weight: 62kg) after single full breath-holding. Three dimensional lung images were reconstructed (minimal threshold value: -1,000HU, maximal threshold values: -150,-250, -350, -450HU) to obtain total lung volume(TLV) on a histogram. Total lung volume measured by spiral CT was compared with TLV obtained by spirometry.
RESULTS
Mean TLV measured by spirometry was 5.62 Land TLV measured by CT at maximal threshold values of -150, -250, -350, and -450HU was 6.63, 5.33, 5.15, and 4.98 L, respectively. Mean absolute differences between the modalities of 0.17L(3%), 0.32L(5.6%), 0.48L(8.5%), 0.65L(11.5) were statistically significant(p<0.001). Linear regression coefficients between the modalities were 0.99, 0.97, 0.95,and 0.94 and no statistically significant differences in accuracy of threshold levels in the estimation of lung volume(r=0.99, standard error=0.034L in all) were seen.
CONCLUSION
TLV measured by spiral CT closely approximated that measured by spirometry. Spiral CT may be useful as a means of evaluating lung function.

Keyword

Lung, volume; Lung, function; Lung, CT; Computed tomography(CT), helical technology

MeSH Terms

Adult
Female
Humans
Linear Models
Lung
Male
Spirometry*
Tomography, Spiral Computed*
Total Lung Capacity*