it is cartilaginous airways of <10mm and [10mm were con-apparent that airflow obstruction in asthma is often not sidered separately, the increase in wall area was found tocompletely reversible. A number of investigators have re- involve all airway groups. Comparable changes have alsoported that asthmatic patients frequently have persistent been described in resected and post-mortem lung speci-lung function abnormalities despite clinical remission.