Optimizing airway wall segmentation and quantification by reducing the influence of adjacent vessels and intravascular contrast material with a modified integral-based algorithm in quantitative computed tomography

• Published in: PloS one Vol. 15; no. 8; p. e0237939
• Main Authors: Konietzke, Philip, Weinheimer, Oliver, Wagner, Willi L., Wuennemann, Felix, Hintze, Christian, Biederer, Juergen, Heussel, Claus P., Kauczor, Hans-Ulrich, Wielpütz, Mark O.
• Format: Journal Article
• Language: English
• Published: San Francisco Public Library of Science 19.08.2020; Public Library of Science (PLoS)
• Subjects: Airway; Algorithms; Allergic diseases; Animals; Biology and Life Sciences; Blood vessels; CAT scans; Catheters; Computed tomography; Computer and Information Sciences; Coronary vessels; Diagnosis; Diameters; Disease; Drug dosages; Engineering and Technology; Hospitals; Integrals; Medical examination; Medical research; Medicine and Health Sciences; Methods; Nuclear medicine; Optimization; Physical Sciences; Pulmonary arteries; Quantitative analysis; Research and Analysis Methods; Respiratory tract diseases; Segmentation; Thickness measurement; Veins & arteries; Ventilation; Wall thickness; Germany
• ISSN: 1932-6203; 1932-6203
• DOI: 10.1371/journal.pone.0237939

Quantitative analysis of multi-detector computed tomography (MDCT) plays an increasingly important role in assessing airway disease. Depending on the algorithms used, airway dimensions may be over- or underestimated, primarily if contrast material was used. Therefore, we tested a modified integral-based method (IBM) to address this problem. Temporally resolved cine-MDCT was performed in seven ventilated pigs in breath-hold during iodinated contrast material (CM) infusion over 60s. Identical slices in non-enhanced (NE), pulmonary-arterial (PA), systemic-arterial (SA), and venous phase (VE) were subjected to an in-house software using a standard and a modified IBM. Total diameter (TD), lumen area (LA), wall area (WA), and wall thickness (WT) were measured for ten extra- and six intrapulmonary airways. The modified IBM significantly reduced TD by 7.6%, LA by 12.7%, WA by 9.7%, and WT by 3.9% compared to standard IBM on non-enhanced CT (p<0.05). Using standard IBM, CM led to a decrease of all airway parameters compared to NE. For example, LA decreased from 80.85±49.26mm.sup.2 at NE, to 75.14±47.96mm.sup.2 (-7.1%) at PA (p<0.001), 74.96±48.55mm.sup.2 (-7.3%) at SA (p<0.001), and to 78.95±48.94mm.sup.2 (-2.4%) at VE (p = 0.200). Using modified IBM, the differences were reduced to -3.1% at PA, -2.9% at SA and -0.7% at VE (p<0.001; p<0.001; p = 1.000). The modified IBM can optimize airway wall segmentation and reduce the influence of CM on quantitative CT. This allows a more precise measurement as well as potentially the comparison of enhanced with non-enhanced scans in inflammatory airway disease.