Role of CT virtual endoscopy in tracheobronchial foreign body inhalation

ABSTRACT

As foreign bodies [FBs] in respiratory tract are usually in children, history is always vague. Current practice is diagnosis by conventional X-ray. Because most of inhaled FBs are radiotranslucent, rigid endoscopy is carried out for diagnostic purpose in high percentage of cases. The aim of this work is to evaluate a new CT technique called virtual endoscopy to avoid undue rigid endoscopy, which carries hazards for patients. This study was carried out, between January 2000 and 2002, on 34 patients [mean age 19 months +/- 15.5] with suspected history of foreign body inhalation. Conventional X-ray study detected only 2 cases [5.9%] with radiopaque FB. By virtual bronchoscopy, 21 cases [61.8%] diagnosed as having inhaled FB compared to 20 cases [58.8%] diagnosed by rigid endoscopy. 13 Cases [38.2%] diagnosed by virtual bronchoscopy as having no FB intialation compared to 14 cases [41.2%] diagnosed by rigid endoscopy. We can conclude that CT virtual endoscopy, which is more safer than rigid one, has high sensitivity [95%], specificity [85.7%], predictive value of positive test [90.5%], predictive value of negative test [92.3%] and diagnostic accuracy [91.2%]. If CT virtual endoscopy is available; we strongly recommend it for every patient with suspected FB inhalation and negative X-ray finding: