Assessment of current techniques for determining tracheal luminal stenosis in dogs.
OBJECTIVE
To assess the accuracy of current antemortem and postmortem techniques for determining tracheal luminal stenosis.


METHODS
15 dogs.


METHODS
Percentage of tracheal luminal stenosis (PTLS) was determined by 6 methods, using measurements obtained by radiography, tracheoscopy, and necropsy after selected tracheostomy techniques were performed. To calculate PTLS, dorsoventral tracheal diameter was measured from preoperative and postoperative lateral cervical radiographic views. Preoperative or normal tracheal segments adjacent to the stenotic area were used to obtain normal tracheal diameter measurements. Planimetrically determined cross-sectional area (CSA), obtained from pre- and postoperative tracheoscopic photographs, was used to calculate PTLS. The CSA of tracheal specimens obtained at necropsy was determined, using the formula for an ellipse. Percentage of luminal stenosis was calculated, using CSA of the stenotic site and of segments craniad and caudad to the site obtained at necropsy or at surgery. All methods were compared with the control method of planimetrically determined CSA of sections obtained at necropsy of the tracheostomy and segments craniad and caudad to the site.


RESULTS
Correlation was poor for radiographic and tracheoscopic techniques (r = 0.146 to 0.458, P > 0.05) The formula for an ellipse accurately predicted PTLS when measurements obtained at surgery (r = 0.516, P = 0.049) or segments craniad and caudad (r = 0.853, P < 0.001) to the site were used.


CONCLUSIONS
Antemortem methods of assessing PTLS did not correlate with control planimetric methods. Methods using CSA determined by tracheal diameter were weakly correlated to control planimetric techniques.


CONCLUSIONS
Accurate measurement of the degree of tracheal stenosis cannot be made in clinical patients using current techniques.
Huber
M L
ML
Department of Small Animal Surgery and Medicine, College of Veterinary Medicine, Auburn University, AL 36849, USA.
Henderson
R A
RA
Finn-Bodner
S
S
Macintire
D K
DK
Wright
J C
JC
Hankes
G H
GH
D000818:Animals; D004283:Dog Diseases / Q000175:diagnosis* / Q000000981:diagnostic imaging / Q000473:pathology; D004285:Dogs; D007091:Image Processing, Computer-Assisted; D016014:Linear Models; D008297:Male; D011859:Radiography; D014132:Trachea / Q000000981:diagnostic imaging / Q000473:pathology* / Q000601:surgery; D014135:Tracheal Stenosis / Q000175:diagnosis / Q000473:pathology / Q000662:veterinary*; D014139:Tracheostomy / Q000009:adverse effects / Q000379:methods / Q000662:veterinary*