Cryptogenic organizing pneumonia

Case contributed by Yi-Jin Kuok
Diagnosis almost certain


Consolidation not responding to multiple courses of antibiotics.

Patient Data

Age: 35 years
Gender: Female

There are areas of clearing consolidation with central ground glass, also known as the reverse halo sign. Instead of ground glass surrounding an opacity/nodule ("halo sign"), there is an opacity/consolidation with a central ground glass density ("reverse halo").

There is the so called "atoll sign". As the consolidation clears away from the peripheries, the resultant curvilinear band of atelectasis is akin to an atoll.

Case Discussion

Features are, in the correct clinical setting, consistent with cryptogenic organizing pneumonia (COP)

How to use cases

You can use Radiopaedia cases in a variety of ways to help you learn and teach.

Creating your own cases is easy.

Updating… Please wait.

 Unable to process the form. Check for errors and try again.

 Thank you for updating your details.