case_images: PMC10777767_01
case_images: Central airway obstruction due to idiopathic subglottic stenosis. (a) Chest X-ray is normal. (b) Flow-volume curve shows the blunting pattern resembling a rectangle. (c) Cervical computed tomography (CT) in the sagittal plane reveals the narrow position of trachea (red arrow). (d) Bronchoscopic images with mucous edema and obstruction right below the glottis (red arrow). (e) Cervical CT in the axial plane reveals the narrow position of trachea (red arrow).
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case_images: Because of the normal CXR (Figure 1(a)) and the result of spirometry with forced expiratory volume in 1 s (FEV1)/forced vital capacity (FVC) 0.76, she was diagnosed and treated as an asthmatic at another hospital during 1 year before seeking to our hospital. Re-evaluation of her spirometry revealed the blunting of both limbs of the F-V curve (Figure 1(b)). Suspecting tracheal obstruction, the cervical computed tomography (CT) with contrast material undertaken showed the subglottic stenosis (Figure 1(c) and (e)). Flexible bronchoscopy revealed the narrowness of trachea right below the glottis 1 cm (Figure 1(d)) and resulted in the episode of dyspnea immediately post-bronchoscopy.
case_images: PMC10777767_02
case_images: Central airway obstruction at the inferior limit of trachea. (a) Chest X-ray revealed normal lung fields but suspecting the loss of patency at the lower limit of trachea (red arrow). (b) Chest computed tomography reveals the mediastinal tumor invasive into the trachea.
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case_images: His CXR showed normal lung fields accompanied by the mediastinal bulging (Figure 2(a)). The chest CT undertaken revealed the mediastinal tumor invasive into the lower third of trachea right above the carina (Figure 2(b)).
case_images: PMC10777767_03
case_images: Non-resolving pneumonia relating to central airway obstruction. (a) Chest X-ray revealed bilateral alveolar infiltrates. (b) Bronchoscopic images showed tumorous lesions causing airway obstruction at the lower part of trachea.
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case_images: His CXR revealed bilateral alveolar infiltrates predominant in the upper lobes (Figure 3(a)). Suspecting an airway obstruction, the bedside flexible bronchoscopy undertaken revealed tumorous lesions at the lower third of trachea and in both main bronchi (Figure 3(b)) (histopathological result was lung adenocarcinoma).
case_images: PMC10777767_04
case_images: Central airway obstruction due to post-intubation tracheal stenosis. (a) Flow-volume loop showed the pattern of fixed upper airway obstruction. (b) and (c) The images of chest computed tomography in axial and sagittal planes reveal the tracheal stenosis (red arrows).
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case_images: fig4-2050313X231225327
case_images: His CXR was normal, and the result of spirometry showed the pattern of fixed upper airway obstruction in F-V loop (Figure 4(a)). His chest CT scan showed tracheal stenosis (smallest inner diameter of 4 mm) at the level of cervical (C7) and thoracic (T1) vertebra (Figure 4(b) and 4(c)).
case_images: PMC10777767_05
case_images: Esophageal squamous cell carcinoma causing central airway obstruction. (a) Chest X-ray with the narrowing of trachea (red arrow). (b) Flow-volume loop with the pattern of variable intrathoracic obstruction. (c) The esophageal tumor compressing and pushing the trachea.
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case_images: However, the narrowing of the trachea on CXR could be identified with the caution of evaluation (Figure 5(a)). The result of spirometry showed the F-V loop with the pattern of variable intrathoracic obstruction (Figure 5(b)). Suspecting mediastinal tumor, chest CT scan with contrast material undertaken showed the mass (43 x 42 mm) compressing and pushing the trachea (Figure 5(c)).