Brief Answer: Collapse of part of lung Detailed Answer: Hi, I have gone through your query. Atelectasis means collapse of lung resulting in absent gas exchange. Linear Atelectasis suggest that there is collapse of lung in a linear pattern. It is a very common finding in chest x-rays. It can be caused by normal exhalation or due to some other causes like foreign body, mucus plug, smoking, old age, blockage, tumors or tubercle. Lingula is a part of lung and it scarring may be due to previous infection or inflammation. Hope I have answered your query. If you have any further questions I will be happy to help.

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