Pulmonary arteriovenous malformation (pAVM)

Case contributed by Yaïr Glick
Diagnosis certain



Patient Data

Age: 55 years
Gender: Female

Lungs are clear, hila appear normal. No pleural effusion.
Cardiac, mediastinal, and aortic shadows of normal width.

5 days later


New ovoid opacity measuring 5.5 cm in length in left lower lobe.

2 days later


Saccular pulmonary arteriovenous malformation in left lower lobe between segmental pulmonary artery and segmental tributary to left lower pulmonary vein. Thrombus apparently filling up the rest of the aneurysmal sac. Several bullae abutting the aneurysm.

Case Discussion

Known small pulmonary arteriovenous malformation (pAVM) in left lower pulmonary lobe (LLL). Presented to the emergency department with fever. Chest x-ray on arrival was normal.
 12 hours later, developed severe neck pain and showed signs and symptoms of meningitis. Complete blood count and chemistry panel came back normal. Extensive testing for pathogens all came back negative - putative diagnosis of aseptic meningitis. Had grand mal seizures. CT head and MRI brain (not shown) were normal.
A consecutive chest x-ray revealed a new ovoid opacity in the LLL. CTPA showed it to be the pAVM, only it had grown substantially. The seizures were thought to have caused its rapid growth 1.

NB: I contributed the images for the reference article.

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.