Related Experiment Video
Updated: Jun 21, 2026

Measuring Diaphragm Thickness and Function Using Point-of-Care Ultrasound
Published on: November 3, 2023
Changes in tracheal dimensions during inspiration and expiration in healthy dogs as detected via computed tomography
Caroline D Leonard1, Lynelle R Johnson, Cecily M Bonadio
1Veterinary Medical Teaching Hospital, School of Veterinary Medicine, University of California, Davis, CA 95616, USA.
Objective:
To determine the degree of fluctuation in tracheal dimensions between forced inspiration and passive expiration in healthy dogs of various sizes.
Animals:
10 client-owned dogs with no evidence of respiratory disease or tracheal collapse.
Procedures:
Anesthetized dogs underwent a computed tomographic examination during forced inspiration and induced but passive expiration to assess tracheal dimensions. Tracheal height, width, and cross-sectional area were measured at inspiration and expiration, and percentage change in dimension was calculated for each variable.
Results:
Measurements were acquired in 10 dogs that ranged in body weight from 3.5 to 47.8 kg. Tracheal cross-sectional area at inspiration and expiration was associated with body weight at all 3 tracheal regions. The percentage change in tracheal height and cross-sectional area was associated with body weight in the cervical but not the thoracic-inlet or thoracic regions. The tracheal cross-sectional area changed by as much as 24.2% (mean, 5.5%), 20.0% (mean, 6.0%), and 18.6% (mean, 6.0%) in the cervical, thoracic-inlet, and thoracic regions, respectively.
Conclusions And Clinical Relevance:
The change in tracheal cross-sectional area from inspiration to expiration was as great as 24% in healthy dogs, and the area was associated with body weight. Respiratory fluctuations appeared to result in changes in tracheal dimension during respiration similar to those reported for humans.
More Related Videos
09:57Four-Dimensional Computed Tomography-Guided Valve Sizing for Transcatheter Pulmonary Valve Replacement
Published on: January 20, 2022
11:31Using Micro-computed Tomography for the Assessment of Tumor Development and Follow-up of Response to Treatment in a Mouse Model of Lung Cancer
Published on: May 20, 2016
Related Concept Videos
Computed Tomography
The technique was invented in the 1970s and is based on the principle that as X-rays pass through the body, they are absorbed or reflected at different levels. In the technique, a patient lies on a motorized platform while a computerized axial tomography (CAT) scanner rotates...
Trachea
Anatomical Features:
Location: About half of the trachea is situated in the neck, anterior to the esophagus, and extends from the larynx (at the level of the...
Imaging Studies III: Computed Tomography
Physical Assessment of the Respiratory Tract II: Inspection
Chest Configuration
The chest configuration can...
Pressure Relationships in Thoracic Cavity
Breathing Mechanisms
Both intra-alveolar and intrapleural pressures rely on specific lung properties. The ability to breathe—allowing air to enter the lungs during...
Pulmonary Ventilation: Inhalation
Boyle's law becomes particularly pertinent when examining respiratory...