Tuberc Respir Dis.  1986 Jun;33(2):110-115. 10.4046/trd.1986.33.2.110.

Slope-Ratio(SR) Analysis in Maximal Expiratory Flow Volume Curve

• KMID: 2528705
• DOI: http://doi.org/10.4046/trd.1986.33.2.110

Abstract

There are numerous parameters for the detection of obstructive airway disease in Maximal Expiratory Flow Volume Loop(Curve). Slope-Ratio(SR) is another new parameter which considered to be useful for the detection of early small airway dysfunction using both MEF ₅₀ and MEF _75• SR was measured in 3 groups of subjects(50 person in each group) and obtained the following results. 1) SR of first group, who have normal limit values of FVC, FEV_1.0, MEF ₅₀, MEF₇₅, was 0.86土 0.24. 2) SR of second group, who have less then 70% predicted MEF ₇₅ but all normal FVC, FEV_1.0, MEF ₅₀, showed 1.30土0.15 3) SR of third group, who have less than 70% predicted MEF ₅₀, FEV_1.0, was 1. 38 土 0.19. 4) Arbitrary value of SR 1.0 appeared to be the marginal value of Small Airway Dysfunction(SAD) in functional aspect. 5) Further SR analysis among the evident obstructive airway disease patients will be needed for the clinically useful parameter.