pleura(redirected from Mediastinal pleura)
Also found in: Dictionary, Thesaurus, Medical, Wikipedia.
pleura(plo͝or`ə), membranous lining of the upper body cavity and covering for the lungslungs,
elastic organs used for breathing in vertebrate animals, excluding most fish, which use gills, and a few amphibian species that respire through the skin. The word is sometimes applied to the respiratory apparatus of lower animals.
..... Click the link for more information. . The pleura is a two-layered structure: the parietal pleura lines the walls of the chest cage and covers the upper surface of the diaphragm, and the pulmonary pleura, or visceral layer, tightly covers the surface of the lungs. The two layers, which are in fact one continuous sheet of tissue, are generally connected to each other. In humans, the pleural cavity is further separated into left and right sides by the heart and pericardial cavity. There is normally a slight amount of watery fluid within the pleural cavity that lubricates the pleural surfaces and allows the lungs to slide freely over the inner surface of the thoracic wall during breathing. When a lung collapses or develops an infection, a condition known as pleurisy can develop. The pleura becomes inflamed, and the pleural cavity becomes noticeably larger. Pleurisy can be extremely painful, but can be medically eradicated in many cases. Mesothelioma is a tumor of the pleura seen most frequently in asbestosasbestos,
common name for any of a variety of silicate minerals within the amphibole and serpentine groups that are fibrous in structure and more or less resistant to acid and fire.
..... Click the link for more information. workers.
the serous membrane covering the lungs and the walls of the thoracic cavity in higher vertebrates, including man.
Mammals have a pulmonary pleura enveloping the lung, and a parietal pleura lining the inner surface of the thoracic cavity. Within the parietal pleura are the costal, diaphragmatic, and mediastinal pleurae. Between the pulmonary and parietal pleurae is a fissure, the pleural cavity, filled with a fluid that is continually renewed. This fluid is produced mainly by the pulmonary pleura and is absorbed chiefly by the costal part of the parietal pleura. The volume of fluid passing through the pleural cavity in 24 hours is approximately 27 percent of the volume of the blood plasma. The pleural fluid decreases friction between the pleurae during respiration. The sinuses—storage spaces that on inhalation partially fill like lungs and increase in volume—are located between the pleurae, in the inferior part of the pleural cavity. The pleura is supplied with blood from the intercostal, internal thoracic, and diaphragmatic arteries. It is innervated by the vagus, intercostal, and diaphragmatic nerves. Pain receptors are concentrated in the parietal pleura.