Reliability of upper airway linear, area, and volumetric measurements in cone-beam computed tomography.
BACKGROUND
Our objective was to assess the intraexaminer and interexaminer reliabilities of upper airway linear, area, and volumetric measurements in cone-beam computed tomography.


METHODS
Cone-beam computed tomography scans of 12 subjects were randomly selected from a pool of 132 orthodontic patients. An undergraduate student, an orthodontist, and a dental radiologist independently made linear, area, and volumetric measurements. Linear anteroposterior and transversal measurements, cross-sectional area, sagittal area, minimum axial area, and volume measurements were made. The intraclass correlation coefficient (ICC) was used to assess intraexaminer and interexaminer reliabilities, and measurement errors were assessed. Agreement was further assessed with the Bland-Altman method and 95% limits of agreement.


RESULTS
Overall, the ICC values indicated good reliability for the measurements assessed. The ICC values were greater than 0.9 (excellent) for 93% of intraexaminer and 73% of interexaminer assessments. Transversal width measurements and cross-sectional area at the level of the vallecula, however, had only moderate reliability (minimum ICC, 0.63), large 95% limits of agreement, and the greatest mean measurement errors (as high as 16% and 13% of the mean measurements, respectively). Linear anteroposterior measurements; cross-sectional areas at the levels of the palatal plane, soft palate, and tongue; and sagittal area and volume were reliable measurements, with a minimum ICC of 0.93 and more restricted limits of agreement.


CONCLUSIONS
Based on these results, airway assessments by examiners with different backgrounds might have reliable anteroposterior linear measurements; cross-sectional areas at the levels of the palatal plane, soft palate, and tongue; and sagittal area and volume. The unreliable measurements were linear width, cross-sectional area at the level of the vallecula, and minimum axial area.
Professor, Department of Dental Clinics, Universidade Federal Fluminense, Niterói, Brazil. Electronic address: claudiatrindademattos@gmail.com.
Claudia Trindade
CT
Mattos
PhD student, Department of Pediatric Dentistry and Orthodontics, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brazil.
Christiane Vasconcellos
CV
Cruz
Postgraduate student, Department of Pediatric Dentistry and Orthodontics, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brazil.
Thais Cristina Sobreira
TC
da Matta
Undergraduate student, School of Dentistry, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brazil.
Leonardo de Abreu
Lde A
Pereira
Postgraduate student, Department of Pediatric Dentistry and Orthodontics, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brazil.
Priscilla de Almeida
Pde A
Solon-de-Mello
Associate professor, Department of Orthodontics, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brazil.
Antônio Carlos de Oliveira
AC
Ruellas
Associate professor, Department of Orthodontics, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brazil.
Eduardo Franzotti
EF
Sant'anna
D019412:Anatomy, Cross-Sectional / Q000706:statistics & numerical data; D002508:Cephalometry / Q000706:statistics & numerical data; D054893:Cone-Beam Computed Tomography / Q000706:statistics & numerical data*; D005931:Glottis / Q000000981:diagnostic imaging; D006801:Humans; D021621:Imaging, Three-Dimensional / Q000706:statistics & numerical data; D009929:Organ Size; D009960:Oropharynx / Q000000981:diagnostic imaging*; D021362:Palate, Hard / Q000000981:diagnostic imaging; D010160:Palate, Soft / Q000000981:diagnostic imaging; D015203:Reproducibility of Results; D014059:Tongue / Q000000981:diagnostic imaging