Cigarette smoking is a major public health problem,
and it is the most common cause of inhalation lung injury.
Inhaling the complex mixture of chemical compounds present in tobacco smoke causes several adverse health effects,
including injury to the tracheobronchial tree and pulmonary parenchyma.
Cigarette smoking-related lung diseases are a wide group of diseases which include chronic obstructive pulmonary disease (COPD),
lung cancer and smoking-related interstitial lung diseases (ILDs).
COPD is characterized by persistent airflow limitation.
It is caused by an enhanced chronic inflammatory response to noxious particles or gases, which can lead to irreversible structural and functional changes in the lungs and airways.
Tobacco smoking is a major cause of COPD,
though not all smokers develop the disease.
Cigarette smoking is an established risk factor for lung cancer.
All major histologic types of lung cancer (squamous cell carcinoma,
small cell carcinoma,
large cell cancer and adenocarcinoma) have been reported to be significantly associated with cigarette smoking [1].
Tobacco smoking is also associated with the development of several ILDs,
which include:
● Respiratory bronchiolitis-interstitial lung disease (RB-ILD)
● Desquamative interstitial pneumonitis (DIP)
● Pulmonary Langerhans cell histiocytosis (PLCH)
● Idiopathic pulmonary fibrosis (IPF)
● Combined pulmonary fibrosis and emphysema (CPFE)
* Airspace enlargement with fibrosis (AEF): this entity has been identified pathologically as a smoking-related change [2] that could be included on the spectrum of smoking-related ILDs.
Of the imaging modalities available,
Computed Tomography (CT) plays an integral role in the assessment of smoking-related lung diseases: it can be used to evaluate the presence,
extent and severity of smoking-related-ILDs,
to characterize emphysema and airway abnormalities,
to stage lung cancer and to help guide management.
Besides,
quantitative CT analysis has an important role in determining emphysema severity and the magnitude of expiratory gas trapping [3].