Histopathology of the pleura

The lungs are nestled in a cavity, shielded by the pleura. The pleura, a form of serous membrane, wraps around each lung. This membrane arrangement consists of two layers: the visceral and parietal pleurae. The visceral pleura lines the surface of the lungIn contrast, the parietal pleura is the outer layer and contacts to the thoracic wall, the mediastinum, and the diaphragm. The hilum is the point of connection between the visceral and parietal layers. The space between the parietal and...

The lower respiratory tract is anatomically composed of several vital structures, including the larynx, trachea, bronchial tree, alveoli, lungs, and pleurae. Each component has a specific function, and all are intricately connected to ensure efficient respiration.
The Larynx
It is located between the pharynx and the trachea, acts as a passageway for air, and hosts several critical structures, such as the epiglottis, vocal cords, and glottis. The epiglottis acts as a gateway, guiding food to the...

The pathophysiology of pneumonia involves the following steps:

The pleura is a vital part of the respiratory system. It's a double-layered membrane surrounding the lungs and lining the chest cavity. The two layers of the pleura are:

Pleural effusion is an abnormal fluid accumulation in the pleural cavity, a narrow space between the lungs and the chest wall. It is not a disease per se but rather a symptom or indication of an underlying disease. In normal circumstances, this space contains a small amount of fluid (5 to 15 mL), a lubricant facilitating the non-frictional movement of the pleural surfaces.
There are two main types of pleural effusion: transudative and exudative. They are differentiated using Light's criteria,...

Pneumothorax means the presence of air in the pleural space — the thin potential gap between the visceral and parietal pleura. This condition disrupts the normal pressure balance that keeps the lungs inflated, leading to partial or complete collapse of the affected lung.Normal physiologyUnder normal conditions, the pleural space maintains a slightly negative intrapleural pressure, which keeps the lungs expanded against the chest wall. This negative pressure creates a delicate balance between...