Journal Article

Dynamic Airway Evaluation with Volume CT: Initial Experience

Roberts, Heidi C., MD, FRCP(C), Chapman, Kenneth R., MD, MSc, FRCPC, FACP, FCCP, Paul, Narinder S., MRCP (UK), FRCR, FCPC, Wagnetz, Ute, MD, Patsios, Demetris, MD, BMBCh, MRCP, FRCR (UK), Chung, Taebong, MD

2010

Overview

Abstract Purpose The purpose of the study was to prospectively establish the use of a novel multidetector computed tomography unit (MDCT) with 320 × 0.5 detector rows for the evaluation of tracheomalacia by using a dynamic expiratory low-dose technique. Methods Six adult patients (5 men, 1 woman; mean age, 53.7 years [37–70 years]) referred for a clinical suspicion of tracheomalacia were studied on a 320-row MDCT unit by using the following parameters: 120 kVp, 40–50 mA, 0.5-second gantry rotation, and z-axis coverage of 160 mm sufficient to cover the thoracic trachea to the proximal bronchi. Image acquisition occurred during a forceful exhalation. The image data set was subject to the following analyses: cross-sectional area of airway lumen at 4 predefined locations (thoracic inlet, aortic arch, carina, and bronchus intermedius) and measurement of airway volume. Results All 6 patients had evidence of tracheomalacia, the proximal trachea collapsed at a later phase of expiration (3–4 seconds) than the distal trachea (2–3 seconds). The most common region of airway collapse occurred at the level of the aortic arch (5/6 [83%]), Three patients (50%) had diffuse segmental luminal narrowing that involved the tracheobronchial tree. The radiation dose (estimated dose length product, computed tomography console) measured 293.9 mGy in 1 subject and 483.5 mGy in 5 patients. Conclusions Four-dimensional true isophasic and isovolumetric imaging of the central airways by using 320-row MDCT is a viable technique for the diagnosis of tracheomalacia; it provides a comprehensive assessment of airways dynamic.

• Publisher: Elsevier Inc,SAGE PUBLICATIONS, INC
• Subject: 320-row multidetector computed tomography / Adult / Aged / Female / Humans / Isophasic imaging / Male / Medical disorders / Middle Aged / Prospective Studies / Radiographic Image Interpretation, Computer-Assisted / Radiology / Throat / Tomography / Tomography, X-Ray Computed - methods / Tracheomalacia / Tracheomalacia - diagnostic imaging / Tracheomalacia - physiopathology