Chronic obstructive pulmonary disease (COPD) is a major cause of morbidity and mortality all over the world. Smoking is considered as an important risk factor, but other risk factors are present. Around 30 % of patients with COPD are non-smokers.

Cessation of smoking in patients with COPD causes decreases the presence of micronodules and other criteria of CT chest.

In last few years, some researchers reported that cessation of smoking raise the apparent extent of emphysema. The cause is not obvious, but this paradoxical fall in lung density is thaught to be resulting from decrease in inflammation after smoking cessation.

CT chest criteria of COPD in active smokers, non-smokers and ex-smokers seem to be different.

So, comparison between CT chest Criteria of COPD in smokers, ex-smokers and non-smokers will be searched in this study to detect the role of multislice computed tomography (MSCT) chest in differentiation between COPD patients according to their smoking status.

Basic ethical principles of medical research; beneficence (do well), non-maleficence (do no harm), respect and distributive justice were implemented. The study will be carried out in accordance with the Declaration of Helsinki and the principles of good clinical practice.

Inclusion Criteria:

1. All patients with chronic obstructive Pulmonary Disease.
2. Patients above 18 years.

Exclusion Criteria:

1. Patients with unclear smoking history.
2. Patients with active pneumonia.
3. Patients with acute COPD exacerbation.

COPD patients either smokers, ex-smokers or non-smokers

COPD MSCT criteria smoking status

2 years

Medical researchers