<aside>

A bronchocele (also called mucoid impaction or mucous plug) is a dilated, mucus-filled bronchus that appears as a tubular or branching intrapulmonary opacity on imaging. It results from bronchial obstruction with accumulation of secretions.

</aside>

Etiopathogenesis

Causes of Obstruction

Congenital / Structural
- Bronchial atresia (classic cause; developmental absence of proximal bronchus).
- Congenital bronchial stenosis.
Acquired
- Endobronchial tumor (carcinoid, bronchogenic carcinoma).
- Foreign body aspiration.
- Post-inflammatory stricture (TB, sarcoidosis).
- Allergic bronchopulmonary aspergillosis (ABPA).

Pathophysiology

Proximal obstruction → distal bronchus fills with mucus → bronchus dilates.
Often associated with distal hyperinflation (via collateral ventilation) or infection.

Clinical Features

Often asymptomatic (esp. congenital bronchial atresia).
Recurrent chest infections, cough, wheeze.
Hemoptysis (if underlying tumor or infection).

Imaging Features

Modality	Imaging features
CXR	• Tubular or branching opacity (“finger-in-glove” appearance).
• Localized hyperlucency if associated with hyperinflation (bronchial atresia).
CT	• Mucoid impaction: tubular, branching, or cystic opacities (often Y- or V-shaped).
• Finger-in-glove sign: branching, tubular, low-attenuation opacities representing mucus-filled bronchi.

Surrounding lung may show: • Hyperinflation (bronchial atresia). • Bronchiectasis. • Consolidation (superinfection). | | MR | • T1: variable, often hypointense. • T2: hyperintense tubular/branching structures. • Useful if distinguishing from vascular lesions |

Differentials

Vascular malformations (can mimic branching opacity; CT angiography differentiates).