Most common type of emphysema clinically is:

Centriacinar emphysema It is most common type of emphysema seen clinically. It involves central pa of acinus with sparing of alveoli. Seen in smokers . Upper Lobes of lung are affected Due to the destruction of alveolar walls, a lack of elastic recoil causes air to become trapped in alveoli, and, thus, airflow obstruction occurs on expiration. -Histology Image of Centriacinar emphysema showing fragmented and free floating alveolar septae