Paraseptal emphysema is characterized by the destruction and
dilation of the alveoli located near the pleura, along the lung
margins, and adjacent to the interlobular septa. This type of
emphysema predominantly affects the upper lung zones and can be
found in isolation or alongside other forms of emphysema, such as
centrilobular or panlobular emphysema. The pathogenesis involves
the breakdown of alveolar walls, leading to the formation of
subpleural bullae or cyst-like spaces that can predispose patients
to spontaneous pneumothorax (collapsed lung) if these bullae
rupture. Patients with paraseptal emphysema may present with
shortness of breath, but symptoms can vary widely depending on
the extent of lung involvement. Diagnosis is primarily made using
high-resolution CT (HRCT) scans, which show enlarged airspaces
near the lung periphery, and may sometimes reveal bullae. While
paraseptal emphysema is often seen in smokers, it can also occur
in younger, otherwise healthy individuals, particularly when
associated with bullous disease (Etesami)
