False positive pulmonary embolus - CTPA

Case contributed by Dr Chris O'Donnell

Presentation

Sudden hypotension at time of prostatic biopsy, no bleeding. Pulmonary hypertension on echocardiogram

Patient Data

Age: 75
Gender: Male

Routine CTPA

CT

Inadequate technique missing the contrast bolus ie contrast predominately in the left side of the circulation missing the pulmonary circulation

Repeat CTPA

CT

CT examination repeated on same day with earlier initiation of the image acquisition. 

Once the contrast bolus is "caught" in the pulmonary circulation, the examination is normal ie no PE

Case Discussion

IN CTPA, the mean HU density of contrast must be > 250 in the pulmonary outflow tract in order to avoid the possibility of flow-related artefacts in the pulmonary artery branches

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.