HIFU stands for “High Intensity Focused Ultrasound”.
Most people understand ultrasound, because they have seen ultrasound scans of babies, gallbladders, kidneys and many other internal organs. This sort of ultrasound is called diagnostic ultrasound, “B mode” ultrasound or greyscale ultrasound.
Very low ultrasound energy is used to bounce sound waves off internal structures to create a picture of the inside noninvasively.
In HIFU, a much more powerful ultrasound is used. In additoin, it is concentrated like a cone. The base of the cone, at the ultrasound head, is very low power. However, as the beam goes through the tissue, it is focused to a single point. Tissue ablation only occurs precisely at that focused point.
The HIFU Echotherapy treatment with Sonovein can be performed in an outpatient room. It does not need an operating theatre.
Just like with a diagnostic ultrasound, gel is put on the skin over the vein to be treated. The Sonovein treatment head is then placed over the vein.
Once the treatment head is over the vein, simple diagnostic ultrasound in the treatment head is used to identify the vein. This enables the surgeon to aim the treatment beam precisely.
When the HIFU is fired, ultrasound energy passes through the skin without damaging it. As explained above, the ultrasound is not focused at the skin and so the energy level is very low. As the energy passes into the body, it is focused onto the precise point that has been selected. For varicose veins, this will be the damaged vein causing the venous reflux.
As the HIFU beam hits the vein, the vein is heated and permanently destroyed.
Laser or radiofrequency ablation of varicose veins relies on a catheter being passed into the vein to be treated. This is why it is called “endovenous surgery”. The catheter is passed inside the vein.
Once inside the vein, a lot of fluid is injected around it. This is called tumescent anaesthesia. Research has suggested that this is the most painful part of modern day varicose vein surgery.
When the laser or radiofrequency is fired, temperatures are in excess of 120°C – and with some lasers several hundred degrees centigrade.
With HIFU Echotherapy, nothing is passed into the vein at all. The whole treatment is performed from outside of the vein – the treatment head is actually outside of the body!
The ultrasound passes through the skin and tissue without causing any damage, until it hits the target. At this point, the ultrasound is focused into a very small area which is heated to about 70-90°C. This is just enough to ablate the target vein, but without damaging any surrounding structures. In addition, there is not enough heat produced to cause carbon or to burst the vein. These are problems that can happen with endovenous laser.
Currently HIFU Echotherapy treatment of varicose veins with Sonovein is restricted to very few experts centres around the world. The only one in the UK is The Whiteley Clinic.
Prof Mark Whiteley won an international prize in November 2019 at the American Vein and Lymphatic Society. He is teaching vein specialists who work at The Whiteley Clinic how to perform the technique and how to get the best results. He is also running international courses to teach vein experts from all around the world.
If you would like to know more about HIFU Echotherapy treatment of varicose veins using Sonovein, please contact us at The Whiteley Clinic.
During the current lockdown, we are able to perform video consultations for those patients who want to know if they might be suitable. Patients who appear to be suitable will then be ready to have scans and treatment as soon as the lockdown is lifted.