The outside of the airway is cartilaginous, so it is rarely blocked. If blockage occurs, it is common to inhale foreign bodies, such as beans or jelly, which can cause difficulty in breathing. There are also masses or growths in the airway, such as growths, whether benign or malignant tumors, which can cause obstruction of the airway. In addition, in old age, the cartilage does not contain enough calcium, resulting in collapse of the airway, which requires a tracheal stent to help support it. In addition, when a mediastinal tumor is present, it may compress the airway and flatten it, which may also lead to difficulty in breathing due to airway obstruction. Inflammation of the larynx may also cause inspiratory difficulties similar to those of airway obstruction, such as laryngeal edema, which should be treated according to different causes.