Endovenous laser ablation (EVLA) and Radiofrequency ablation (RFA) are techniques that have become available over the last 10-15 years for the treatment of varicose veins. As a general rule these techniques will only deal with the underlying cause/source of their varicose veins. These techniques, for most patients, do not remove or destroy the visible varicose veins.

Radiofrequency ablation is a minimally invasive technique to destroy the greater saphenous vein (GSV) in the thigh and/or the small saphenous vein (SSV) at the back of the calf. Both of these veins commonly feed into visible varicose veins. RFA may occasionally be used for other veins such as the anterolateral thigh vein and there is a dedicated RFA device available for treating perforating veins.

RFA is essentially bipolar diathermy. Diathermy refers to electrically induced heat and the bipolar indicates that the electrical current does not pass through the body only through the catheter. By passing an electrical current through a bipolar catheter inside the vein heat is generated and temperatures of 120°C are attained. The heat produced destroys the vein but the procedure relies on direct contact between the catheter and the vein wall. To facilitate the process the vein needs to be as tightly wrapped around the catheter as possible so external compression is applied to the vein using tumescent anaesthesia (injection of fluid containing a local anaesthetic agent) and the leg is elevated to collapse the vein. There is an electrical feedback mechanism integrated into the fibre which can alter the energy delivery to maintain a constant temperature.

There is one dominant RFA device, the VNUS ClosureFast™ (Covidien). There is another device - the Olympus Celon RFITT™ which uses a continuous pull back technique similar to EVLA systems.

Endovenous laser treatment is a minimally invasive technique to destroy the greater saphenous vein (GSV) in the thigh and/or the small saphenous vein (SSV) at the back of the calf.

Laser is an acronym and stands for "Light Amplification by Stimulated Emission of Radiation. Laser light is monochromatic (single wavelength) light produced from a laser medium and then amplified to produce a powerful beam

There are at least 5 types of laser available for use in EVLA. The different lasers vary in the wavelength of the laser light produced and there are some theoretical advantages and disadvantages of each of these different types of lasers. There is little evidence to support one laser over another. Presently there are lasers working at 810, 940, 980, 1320 and 1470nm wavelengths. EVLT™ is a particular brand of device that is used for EVLA.

RFA and EVLA sound impressive, but they are merely alternative techniques that can be used to destroy the greater saphenous vein in the thigh or the small saphenous vein at the back of the calf when they are incompetent and need to be ablated. RFA or EVLA are alternatives to stripping of these veins and also replace the disconnection of veins performed through a small incision either in the groin or behind the knee (saphenofemoral and saphenopopliteal disconnection).

Sclerotherapy, which is a chemical foam injected to damage the vein, can also be used to occlude the GSV and SSV. In EVLT and RFA the veins are destroyed by heating them to a high enough temperature to damage the vein wall.

The first part of the procedure involves inserting a catheter (fine tube) into the vein to be treated (cannulation). This is usually done by using ultrasound to guide a fine hollow needle into the vein. A wire is then passed into the vein through the hollow of the needle and the needle removed along the wire. The wire is then passing from outside the skin into the vein. The hollow catheter is then threaded on to the part of the wire on the outside and passed along the wire into the vein. Once the catheter is in position the wire is removed. This is known as the Seldinger technique and is a common method of obtaining access to many structures in the body. Ideally the catheter should be positioned down the leg as far as the abnormal flow is present. If necessary a small incision can be made to obtain access to an appropriate vein if this is difficult using the ultrasound technique.

The radiofrequency catheter or laser fibre is then passed up the vein and positioned no closer than 2cms from the saphenofemoral or saphenopopliteal junctions. These are junctions between the superficial and the deep veins and the distance is to minimise the possibility of damage to the deep veins, but maximise the length of vein to be treated. The video below is an animation of the technique.

In both techniques it is essential that the vein being treated is separated from the surrounding tissues by injecting fluid around the vein (ultrasound guided tumescent anaesthesia). This is for two reasons. Firstly if the procedure is being performed under local anaesthetic with the patient awake the injections prevent pain being felt when the vein is being treated. Secondly, both techniques heat the vein and the heat needs to be dispersed without damaging any of the tissues surrounding the vein. The liquid that is injected is usually a very dilute local anaesthetic and large volumes are injected, often up to 300mls of fluid per leg. This is a simple and straightforward process.

Recurrent varicose veins - there is no treatment for varicose veins which is immune from the possibility of new veins developing. This is because although all the veins that are problematic can be treated it is not possible to remove the underlying tendency to develop varicose veins

Nerve damage - this would be an unusual complication providing the procedure is performed correctly; but occasionally nerves supplying the skin can be heated which may cause some tingling or numbness

Burning of the skin or surrounding tissues - provided plenty of tumescent anaesthesia is used and the procedure performed correctly this is unlikely.

Burning or heat injury to the deep veins is possible but very rare as a number of measures are taken to avoid this problem.