Bronchial atresia

Overview
Bronchial atresia is a disorder in which a segmental bronchus fails to connect with or communicate with the more central airways.

Pathophysiology and Etiology
The underlying basis of the disorder is not clear. It has been hypothesized to be the result of a vascular injury to the lung at approximately 15 to 16 weeks gestation. An alternate hypothesis is that the disorder occurs secondary to separation of the bronchial bud during the 5th to 6th week of gestation. Pulmonary sequestration and bronchogenic cysts also form during this early period of fetal development and may share an underlying pahtophysiology.

The most common anatomic locations include the following:
 * 1) The apical posterior segment of the left upper lobe
 * 2) The left lower lobe
 * 3) The right middle lobe

Epidemiology and Demographcis
Females outnumber males 2:1.

Symptoms and History
The majority of patients are asymptomatic and the mass is discovered as an incidental finding on a routine chest X ray.

If a patient is symptomatic, they complain of dyspnea, cough and wheezing.

By history the patient may have recurrent pulmonary infections.

Lungs
Decreased breath sounds may be present in the affected lung fields.

Chest X Ray
The chest x ray findings are mucoid impaction of a bronchus yielding a branching tubular mass which is surrounded by hyperinflated lung and decreased vascular markings. The differential diagnosis of these radiographic findings include the following:
 * 1) Arteriovenous malformation
 * 2) Granuloma
 * 3) Metastases

Computed Tomography
This is the imaging modality of choice for diagnosing bronchial atresia and demonstrates segmental emphysematous changes beyond the mucous impaction in the bronchus.

Treatment
Conservative management is the usual course of treatment. However, if the patient is symptomatic with respiratory compromise or if their course is complicated by recurrent infection, then surgical resection may be helpful.