From the Guidelines
Linear atelectasis in focal areas of the lung is most commonly caused by bronchial obstruction, which can be due to foreign bodies, tumors, broncholithiasis, or compression by peribronchial lymph nodes, as well as previous pneumonia. The possible causes of linear atelectasis can be categorized into several factors, including:
- Compression of lung tissue from adjacent structures, such as pleural effusions, pneumothorax, or tumors
- Mucus plugging of airways, which can block smaller bronchi and prevent air from reaching distal alveoli
- Post-surgical atelectasis, frequently seen after thoracic or upper abdominal surgeries due to shallow breathing and poor clearance of secretions
- Prolonged bed rest or immobility, contributing to poor ventilation of dependent lung regions
- Inflammatory conditions like pneumonia, which can cause local collapse through exudate accumulation
- Bronchial obstruction from foreign bodies, tumors, or strictures, resulting in linear patterns of collapse
- Pulmonary fibrosis and scarring from previous infections or radiation therapy, causing traction on adjacent lung tissue and creating linear atelectatic bands 1. According to the study by 1, focal bronchiectasis may follow a severe case of pneumonia, but with increasing use of antibiotics in recent years it is more often caused by bronchial obstruction by a foreign body, broncholith, a slowly growing tumor, anatomic distortion following lobectomy, or enlarged peribronchial lymph nodes. Patients with these findings should undergo appropriate imaging (chest X-ray or CT scan) for proper evaluation, and treatment should address the underlying cause, which may include chest physiotherapy, incentive spirometry, bronchodilators, or treatment of underlying infections 1. Early mobilization and deep breathing exercises are essential preventive measures, particularly in hospitalized patients.
From the Research
Possible Causes of Linear Atelectasis
- Linear atelectasis may occur as a consequence of subsegmental bronchial obstruction 2
- Perihilar linear atelectasis can be caused by an obstructing tumor or a variety of other conditions 2
- Resorption atelectasis is caused by resorption of alveolar air distal to obstructing lesions of the airways 3
- Adhesive atelectasis stems from surfactant deficiency 3
- Passive atelectasis is caused by simple pneumothorax, diaphragmatic dysfunction, or hypoventilation 3
- Compressive atelectasis is due to tension pneumothorax, space-occupying intrathoracic lesions, or abdominal distention 3
- Cicatrization atelectasis stems from pulmonary fibrosis 3
- Gravity-dependent atelectasis is the result of gravity-dependent alterations in alveolar volume 3
Association with Lung Cancer
- A statistically significant relationship was observed between the dimension of perihilar linear atelectasis and primary lung cancer 2
- Thick perihilar linear atelectasis is a new diagnostic roentgen sign that suggests subsegmental bronchial obstruction, which can be caused by primary lung cancer 2
Other Conditions
- Linear atelectasis can also be associated with other conditions such as bronchiectasis, which is a condition characterized by chronic inflammation and damage to the airways 4
- Inhaled corticosteroids (ICS) are sometimes used to treat bronchiectasis, although their use is not recommended for all patients with this condition 4
- Chronic obstructive pulmonary disease (COPD) is another condition that can cause atelectasis, and is characterized by chronic inflammation and airflow obstruction 5