3D vascular ultrasound for AAA; by Kim Bredahl.

Kim Bredahl

3D Vascular US

2D approach - do in both planes A P and longitudinal

Poor agreemenet of more than 5 mm between operators is well described

most likely reason is wrong image plane

US reasons

1) calliper palement

2) plane

3) don’t get the lateral measure

4) cardiac phase

Biplane imaging mentioned: being able to see both views on the same screen image

Caval vein, vertebrae etc can be used as landmark registration

To compensate for some of these limitation: usng a centreline approach

Agreement with interobserver variation: 1.9 to 1.6 mm SD so no real change

But in terms of variation from the CTA measurement: Better result, from a 5 mm difference between modalities down to a 2 mm difference

The centreline application inthe philips machine is now fully automatic

when using CT volume as gold standard, the volume approach by US correlates the best

But the volume approach can only be achieved in full in only 46% of patients

By stitching together multiple acquisitions Kim managed to get the full volume scanning % up to 69%

Thrombus is a source of proteolytic enzymes degrading the aortic wall

What to do next : more sensitive tooks, AI, measure hidden growth, measure shape.