Author(s)
Thomas Hudson, MD
Rayane Ait Oubahou, MASc
Luc Mongeau, PhD
Karen M. Kost, MD
Affiliation(s)
McGill Univ. Health Centre, Montreal, CANADA;
Abstract:
Objective: Upper airway obstruction is a challenge for the airway surgeon. Airway protection can be critical, but avoidance of unnecessary tracheostomy must also be considered. Decision making regarding airway remains largely guided by subjective experience and training. This investigation aims to study the relationship between respiratory distress and airway resistance in laryngeal cancer as determined by computational fluid dynamic (CFD) and morphometric analysis.
Methods: Retrospective CT and clinical data were obtained for a series of 20 cases, defined as laryngeal cancer patients who required urgent airway management, and 20 controls. Cases and controls were matched based on T-staging. Image segmentation and morphometric analysis were first performed. Computational models were then created and used to quantify the continuous mass flow and constant static pressure inlet boundary conditions.
Results: The analysis demonstrated a significant relationship between airway resistance and acute obstruction (OR 1.018, 95% CI 1.001-1.045). Morphometric analysis similarly demonstrated a significant relationship when relating measurements based on the minimum cross-section, but not on length of stenosis. Morphometric measurements also showed significance in relating to CFD results, and their relationship demonstrated an exponential increase in airway pressures below 2.5 mm. Tumor subsite did not show a significant difference.
Conclusions: Airway resistance analysis from CFD computation correlated with presence of acute distress requiring emergent management. Morphometric analysis showed a similar correlation, demonstrating a radiologic airway assessment technique on which future risk estimation could be performed. This could be clinically helpful in deciding whether or not to intervene in borderline airways.