Computed tomography measurement of rib cage morphometry in emphysema.
BACKGROUND
Factors determining the shape of the human rib cage are not completely understood. We aimed to quantify the contribution of anthropometric and COPD-related changes to rib cage variability in adult cigarette smokers.


METHODS
Rib cage diameters and areas (calculated from the inner surface of the rib cage) in 816 smokers with or without COPD, were evaluated at three anatomical levels using computed tomography (CT). CTs were analyzed with software, which allows quantification of total emphysema (emphysema%). The relationship between rib cage measurements and anthropometric factors, lung function indices, and %emphysema were tested using linear regression models.


RESULTS
A model that included gender, age, BMI, emphysema%, forced expiratory volume in one second (FEV1)%, and forced vital capacity (FVC)% fit best with the rib cage measurements (R(2) = 64% for the rib cage area variation at the lower anatomical level). Gender had the biggest impact on rib cage diameter and area (105.3 cm(2); 95% CI: 111.7 to 98.8 for male lower area). Emphysema% was responsible for an increase in size of upper and middle CT areas (up to 5.4 cm(2); 95% CI: 3.0 to 7.8 for an emphysema increase of 5%). Lower rib cage areas decreased as FVC% decreased (5.1 cm(2); 95% CI: 2.5 to 7.6 for 10 percentage points of FVC variation).


CONCLUSIONS
This study demonstrates that simple CT measurements can predict rib cage morphometric variability and also highlight relationships between rib cage morphometry and emphysema.
Section of Diagnostic Imaging, Department of Surgery, University of Parma, Parma, Italy. nicola.sverzellati@unipr.it
Nicola
N
Sverzellati
Davide
D
Colombi
Giorgia
G
Randi
Antonio
A
Pavarani
Mario
M
Silva
Simon L
SL
Walsh
Massimo
M
Pistolesi
Veronica
V
Alfieri
Alfredo
A
Chetta
Mauro
M
Vaccarezza
Marco
M
Vitale
Ugo
U
Pastorino
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000704:Analysis of Variance; D015992:Body Mass Index; D005260:Female; D005541:Forced Expiratory Volume; D006801:Humans; D016014:Linear Models; D008297:Male; D008875:Middle Aged; D029424:Pulmonary Disease, Chronic Obstructive / Q000000981:diagnostic imaging / Q000503:physiopathology; D011656:Pulmonary Emphysema / Q000000981:diagnostic imaging* / Q000503:physiopathology; D012272:Ribs / Q000000981:diagnostic imaging*; D012907:Smoking; D013249:Sternum / Q000000981:diagnostic imaging*; D013904:Thoracic Vertebrae / Q000000981:diagnostic imaging*; D014057:Tomography, X-Ray Computed / Q000379:methods*; D014797:Vital Capacity