Bilateral pleural thickening adhesions are more common and are the result of fibrosis due to fibrin deposition and granulation tissue proliferation on the basis of pleural lesions, which increases the thickness of the pleura. They are often the result of healing from previous exudative pleurisy and pleural effusion. Pleural thickening adhesions can be limited or extensive. Extensive thickening of the dirty pleura affects the respiratory function of the lungs, while extensive thickening of the wall pleura can narrow the rib space and reduce the size of the thorax. The most common causes are pneumothorax, hemothorax, trauma, diffuse or limited mesothelioma, tuberculous pleurisy, and septic pleurisy. Pleural thickening and adhesions mostly do not require treatment. There is mild chest tightness will appear to be compensated and reduce or disappear. Strengthening exercise, chest expansion and deep breathing are the best methods. Widespread pleural thickening and adhesions, when it affects the respiratory function of the lungs, can be treated surgically by pleurodesis.