Comparison of Dynamic Expiratory CT With Bronchoscopy for Diagnosing Airway Malacia: A Pilot Evaluation.
OBJECTIVE
To assess the accuracy of dynamic expiratory CT for detecting airway malacia using bronchoscopy as the diagnostic "gold standard."


METHODS
A computerized hospital information system was used to retrospectively identify all patients with bronchoscopically proven airway malacia referred for CT airway imaging at our institution during a 19-month period. CT was performed within 1 week of bronchoscopy. All patients were scanned with a standard protocol, including end-inspiratory and dynamic expiratory volumetric imaging, using an eight-detector multislice helical CT scanner. For both CT and bronchoscopy, malacia was defined as >/= 50% expiratory reduction of the airway lumen. CT and bronchoscopic findings were subsequently jointly reviewed by the radiologist and bronchoscopist for concordance.


RESULTS
Twenty-nine patients (12 men and 17 women; mean age, 60 years; range, 36 to 79 years) comprised the study cohort. CT correctly diagnosed malacia in 28 of 29 patients (97%). The most common presenting symptoms were dyspnea in 20 patients (69%), severe or persistent cough in 16 patients (55%), and recurrent infection in 7 patients (24%). The estimated radiation dose (expressed as dose-length product) for the dual-phase study is 508 mGy-cm, which is comparable to a routine chest CT.


CONCLUSIONS
Dynamic expiratory CT is a highly sensitive method for detecting airway malacia and has the potential to serve as an effective, noninvasive test for diagnosing this condition.
Lee
Karen S
KS
Center for Airway Imaging, Department of Radiology, and Division of Thoracic Surgery and Interventional Pulmonary, Beth Israel Deaconess Medical Center, Boston, MA.
Sun
Maryellen R M
MRM
Center for Airway Imaging, Department of Radiology, and Division of Thoracic Surgery and Interventional Pulmonary, Beth Israel Deaconess Medical Center, Boston, MA.
Ernst
Armin
A
Center for Airway Imaging, Department of Radiology, and Division of Thoracic Surgery and Interventional Pulmonary, Beth Israel Deaconess Medical Center, Boston, MA. Electronic address: aernst@bidmc.harvard.edu.
Feller-Kopman
David
D
Center for Airway Imaging, Department of Radiology, and Division of Thoracic Surgery and Interventional Pulmonary, Beth Israel Deaconess Medical Center, Boston, MA.
Majid
Adnan
A
Center for Airway Imaging, Department of Radiology, and Division of Thoracic Surgery and Interventional Pulmonary, Beth Israel Deaconess Medical Center, Boston, MA.
Boiselle
Phillip M
PM
Center for Airway Imaging, Department of Radiology, and Division of Thoracic Surgery and Interventional Pulmonary, Beth Israel Deaconess Medical Center, Boston, MA.
D000328:Adult; D000368:Aged; D001982:Bronchial Diseases / Q000175:diagnosis*; D001999:Bronchoscopy; D002357:Cartilage Diseases / Q000175:diagnosis*; D015331:Cohort Studies; D045853:Exhalation / Q000502:physiology*; D005260:Female; D006801:Humans; D007091:Image Processing, Computer-Assisted; D008297:Male; D008875:Middle Aged; D011829:Radiation Dosage; D012680:Sensitivity and Specificity; D013223:Statistics as Topic; D036542:Tomography, Spiral Computed; D014133:Tracheal Diseases / Q000175:diagnosis*