Laryngo-tracheal profile: a new method for assessing laryngo-tracheal stenoses.

We present the clinical application of a new method for objective assessment of both grade and length of laryngo-tracheal stenoses (LTS) on a CT-based skeletonization algorithm, called laryngo-tracheal profile (LTP). Extraction of the laryngo-tracheal tract (LTT)-medial axis was performed after S-CT scanning. Orthogonal to the medial axis, the LTT cross-profile was computed, and the length and degree of LTS were presented as line charts. Clinical application of this newly developed method is demonstrated on three patients who had to undergo preoperative assessment before surgical treatment of tracheal stenoses. LTP provides an objective method of assessment of both the length and degree of tracheal stenoses in precise correlation to defined anatomical landmarks. This method provides important additive information for preoperative evaluation as well as for monitoring of therapeutical success. Current methods used so far are able to evaluate the severity of LTS, but do not provide exact quantitative assessment of complex LTS. Especially in CT-scans of strong curved passages, where an overestimation of the cross-sectional area results by an oblique cut of the tubular structure, LTP may overcome this problem by a simple post processing skeletonization algorithm.