What it is
The term describes lung tissue that has partially deflated, like a sponge that has not fully expanded. Small bands of it (“subsegmental” or “linear” atelectasis) are seen all the time, especially at the lung bases.
How common is it?
Very common — particularly after surgery, during shallow breathing, or simply from lying down during the scan.
What's usually next
Mild atelectasis usually needs no treatment; deep breathing and moving around help it re-expand. Larger areas may be evaluated for an underlying cause.
When it usually isn't — and when it might be — worrying
Usually reassuring
- Described as “minimal,” “subsegmental,” or “linear”
- Located at the lung bases
- Noted after surgery or during a period of shallow breathing
Worth discussing with your doctor
- A whole lobe or lung described as collapsed
- Associated with a blockage or mass
- New shortness of breath or low oxygen levels
Questions to ask your doctor
- 1Is this a small, common area or something larger?
- 2Is there any sign of what caused it?
- 3Do I need any follow-up imaging?
- 4Is there anything I should do to help my lungs re-expand?
Educational use only. This explanation helps you understand terminology on your report. It is not a diagnosis, is not FDA-cleared, and does not replace your doctor. Bring questions to your care team.