In vivo and in vitro morphometry of the human trachea

Abstract

Most morphometric studies of the human trachea have relied on plain radiographs with their attendant limitations. Reports using computed tomography (CT) have focused on the growing trachea or one particular dimension. The aim of this study was to document the morphometry of the adult trachea in vivo using high-resolution chest CT scans, supplemented by data from cadavers. Sixty anonymised high-resolution chest CT scans (aged 22-88 years, 40 males) were analyzed. Scans were performed using a standardized breath-holding technique in patients with no distorting intrathoracic pathology. Standardized tracheal measurements included: length, maximum antero-posterior and transverse diameters, volume, subcarinal angle, and carinal position in relation to the tracheal midline. Measurements were also made in 10 cadaver tracheas (aged 68-101 years, 7 males). CT data showed that mean tracheal length (males 105.1 +/- 9.8 mm, females 98.3 +/- 8.7 mm), maximum antero-posterior and transverse diameters, and tracheal volume (males 35.6 +/- 6.8 cm3, females 24.7 +/- 6.1 cm3) were all significantly greater in men (P < or = 0.01). The subcarinal angle was very variable (mean 78 +/- 20 degrees , range 36-121 degrees ) and showed no correlation with age or gender. The carina was sited to the left of the tracheal midline in 49 (81%) patients. Cadaver tracheas had 14-19 tracheal rings and the posterior membranous trachea was wider in men (17.7 +/- 4.4 mm vs. 11.8 +/- 3.0 mm, P = 0.07). In conclusion, there is marked sexual dimorphism in the morphometry of the human trachea. The variation in adult tracheal dimensions in vivo is greater than in standard descriptions. These data may be valuable when interpreting chest CT scans and when calculating respiratory dead space.

Biometric Study of the Internal Dimensions of Subglottis and Upper Trachea in Adult Indian Population

“…In our study, the subglottic and tracheal dimensions in females were comparatively and statistically less than males this is in agreement with most of the other studies [6,8,11]. We have observed that the trachea being a dynamic structure the shape of the trachea varies with the part of the trachea being examined and also with the aging.…”

“…We could not find any references in literature which documented the measurements of the internal diameters of the subglottis. In Table 3 we have shown the comparison of the measurements of our study to earlier studies [3][4][5][6][7][8]. It is found that the average internal diameter in the south Indian population is less than that reported in literature.…”

“…On review of the data available on tracheal diameters [3][4][5][6][7][8]; Table 3 we found that most of the earlier studies have used three methods for measurements. First, cadaver studies using less standardized and detailed measurements have been performed.…”

Normal Tracheal Measurements in the Saudi Population Using Computed Tomography

“…One method entails using radiographs to measure the tracheal width (5). However, the radiographic measurements accuracy was questioned due to inherent methodological issues such as variable magnification, rotation, inspiration, beam penetration, and intrinsic two dimensional nature (6) On the other hand, computed tomography (CT) proved to be a useful, fast and noninvasive method for obtaining tracheal measurements, with results comparable to the gold standard of bronchoscopy (7,8). The focus in the majority of the previously published studies was on measuring the growing trachea of the pediatric population (9,10).…”

“…The focus in the majority of the previously published studies was on measuring the growing trachea of the pediatric population (9,10). Only a few studies addressed tracheal morphometry using CT in adult subjects (6,11,12,13,14,15).Other methods include MRI or ultrasonography. However, the latter is operator dependant (7).…”