Brief Answer:
It is not always related to smoking

Detailed Answer:
Hello, welcome to HCM.

I want to know some history.
1) Since how long you have quit smoking ?
2) What are your present complaints?

Please let me know so i will elaborate on findings.

Regards

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Brief Answer:
Doesn't looks significant

Detailed Answer:
Hello welcome back.

Linear atelectasis have many differential diagnosis.
Main concern for such appeareance is acute symptoms like cough or fever.
Cough could be due to acute infection or damage caused to lung due to smoking.

As per your history , you are not feeling sick nor have any symptoms.

Sometimes while during xrays due to our rotation somes structure overlap and give such imaging apperance.

I would like to advice keep away from smoking .
If in due couarse you develops dry cough then consult pulmonologist and go for HRCT THORAX test which is highly sensitive and specific for lung pathologies.

Hope this may solve your doubts.

Regards.

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