Intravascular Ultrasound (IVUS) is an exciting sophisticated imaging modality that is being used more and more worldwide in venous disease. it is one of the most accurate investigations available to assess problems in the veins and measure them. It is an invasive investigation – that is, it is done from inside a blood vessel and is thus done in theatre under an anaesthetic.
It is far more precise than CT scan, duplex doppler and venogram.
It is typically used when a narrowing (stenosis) is suspected to be present within a vein.
A sheath is inserted into the vein usually through the groin, although it can be behind the knee. Dye is injected to assess the blood vessels as is done in an angiogram.
Then the IVUS may be inserted into the vein. The IVUS is a small catheter with ultrasound on the tip and it can scan from inside the vein to look for any narrowing, old clot or blockages.
If identified, it will accurately measure the size of the vein in order to plan what size stent should be used to open the vein up. It may be used after stent placement in order to see that the stent has opened up well.