title: Variability of bronchial measurements obtained by sequential CT using two computer-based methods.
abstract: This study aimed to evaluate the variability of lumen (LA) and wall area (WA) measurements obtained on two successive MDCT acquisitions using energy-driven contour estimation (EDCE) and full width at half maximum (FWHM) approaches. Both methods were applied to a database of segmental and subsegmental bronchi with LA > 4 mm(2) containing 42 bronchial segments of 10 successive slices that best matched on each acquisition. For both methods, the 95% confidence interval between repeated MDCT was between -1.59 and 1.5 mm(2) for LA, and -3.31 and 2.96 mm(2) for WA. The values of the coefficient of measurement variation (CV(10), i.e., percentage ratio of the standard deviation obtained from the 10 successive slices to their mean value) were strongly correlated between repeated MDCT data acquisitions (r > 0.72; p < 0.0001). Compared with FWHM, LA values obtained using EDCE were higher for LA < 15 mm(2), whereas WA values were lower for bronchi with WA < 13 mm(2); no systematic EDCE underestimation or overestimation was observed for thicker-walled bronchi. In conclusion, variability between CT examinations and assessment techniques may impair measurements. Therefore, new parameters such as CV(10) need to be investigated to study bronchial remodeling. Finally, EDCE and FWHM are not interchangeable in longitudinal studies.
authors.affiliation: Université Paris XIII, UPRES EA 2363 Bobigny, France. pierre-yves.brillet@avc.aphp.fr
authors.forename: Pierre-Yves
authors.initials: PY
authors.lastname: Brillet
authors.forename: Catalin I
authors.initials: CI
authors.lastname: Fetita
authors.forename: André
authors.initials: A
authors.lastname: Capderou
authors.forename: Mihai
authors.initials: M
authors.lastname: Mitrea
authors.forename: Serge
authors.initials: S
authors.lastname: Dreuil
authors.forename: Jean-Marc
authors.initials: JM
authors.lastname: Simon
authors.forename: Françoise
authors.initials: F
authors.lastname: Prêteux
authors.forename: Philippe A
authors.initials: PA
authors.lastname: Grenier
mesh_terms: D000328:Adult; D001249:Asthma / Q000175:diagnosis / Q000000981:diagnostic imaging; D001331:Automation; D001943:Breast Neoplasms / Q000473:pathology; D001980:Bronchi / Q000473:pathology*; D005260:Female; D006801:Humans; D007091:Image Processing, Computer-Assisted; D008875:Middle Aged; D029424:Pulmonary Disease, Chronic Obstructive / Q000175:diagnosis / Q000000981:diagnostic imaging*; D011857:Radiographic Image Interpretation, Computer-Assisted / Q000379:methods*; D013902:Radiography, Thoracic / Q000379:methods; D015203:Reproducibility of Results; D012984:Software; D014057:Tomography, X-Ray Computed / Q000379:methods*