What Causes Hardening of the Lungs?
The lungs can be divided up into basic tissue types. The airways are responsible for transmitting gases between the lungs and the environment. The alveoli are millions of tiny sacs in the lungs that exchange gases between the lungs and the blood. The interstitium includes the tissues between the alveoli and airways. This tissue is elastic, allowing the lungs to expand during inspiration and helping them to contract during expiration, like a rubber band. Some diseases damage these tissues, making the lungs inelastic, preventing them from expanding and contracting, causing breathing difficulty. These are called interstitial lung diseases.
