Please use the form below to submit questions to our Advisory Board. These can relate to any aspect of phlebology and the treatment of related conditions. Previous questions are shown below as they may be helpful to you, but if you do not wish your question to be shared below, you can request this through our contact form.

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Previous questions

Q1 A) We have found a few times AV fistulas connecting to truncal or accessory truncal veins. We immediately took out of consideration foam sclerotherapy or clarivein for such veins. I have successfully performed EVLA on one such vein (SSV), without embolic problems. 1) do you have any safety concern (Thrombus passing into the artery side of the fistula) with EVLA of such veins? - Richard Mueller FCPhleb (New York, USA)

We have never seen patients who present with normal venous reflux who have AV fistulas. However in principle, I would have no safety concern at all about performing EVLA on such a vein. If the fistula is high flow, then I would consider asking my radiologist for arterial embolisation first, and then afterwards would not mind at all what technique I used. If it was a low flow fistula, then EndoVenous Laser Ablation (EVLA) would be ideal to close the vein and, if successful, would indeed close the fistula by shutting the run-off end. As such not only would the refluxing vein be treated but the Fischler ablated at the same time. With adequate EndoVenous Laser Ablation (EVLA), there should be no thrombus at all and so this question should not arise. Further, if for some unknown reason thrombus did occur, the pressure gradient would be from arterial side to ablated side and therefore the should be no concern at all of any passing of thrombus into the arterial side.
Answer by Mark Whiteley MS FRCS (Gen) FCPhleb on 20th June 2012

Q2 B) We have found a few times AV fistulas connecting to truncal or accessory truncal veins. 2) is it ever safe to use sclerosants in the same leg? Extreme example: one of my patients refuses closure of his AVF from ext pudendal artery to his SFJ. Is it safe to foam the dilated tributaries under his ankle ulcer? Following the path of injected foam with ultrasound reminds me every time of the amazing interconnectivity of all levels of leg veins. Might sclerosant get into the pudendal artery? - Richard Mueller FCPhleb (New York, USA)

For the foam sclerosant to get from veins under and ankle ulcer into an external pudendal artery would require a massive injection at very high pressure. I myself would have no problem in injecting foam sclerotherapy to veins under a leg ulcer, provided that all of the reflux (truncal and perforator reflux) had been treated first. Ultrasound guided injection of foam sclerotherapy into veins under an ulcer can then be performed to fill such veins and to make sure injection is stopped before any significant amount of foam reaches the deep veins through competent perforators. Binding of the area is then obligatory immediately for a good result. Any free sclerosant will be protein bound within seconds within the usual bloodstream and although ultrasound studies show the gas continues, there is little active sclerosant left in the wall. Therefore it is highly unlikely any significant amount will get to the pudendal region at all and, even if it did, the pressure gradient from archery to vein would be against it getting into the pudendal artery.
Answer by Mark Whiteley MS FRCS (Gen) FCPhleb on 20th June 2012

Q3 C) We have found a few times AV fistulas connecting to truncal or accessory truncal veins. 3) Can sclerosant surmount the AV pressure gradient in such a case? Many say it cannot. If not, then why the cases of tissue loss with sclerosant ‘crossing the AV border’ in small vein injections. - Richard Mueller FCPhleb (New York, USA)

The answer to your question is purely a dynamic one. The question as to whether sclerosant can flow against the normal pressure gradient in an AV fistula depends on very simple physics – i.e. how much volume you are injecting, how fast and under what pressure. If the volume, speed and pressure of your injection is higher than the arterial pressure and flow in the fistula, then by simple laws of physics you will reverse of flow in the AV fistula and sclerosant will flow from the venous side into the arterial side. If you inject slowly, low volumes and low pressure such that the AV fistula continues to flow in the normal direction, such an event does not happen. Therefore there is no simple “yes” or “no” answer, it is purely a resultant of the equation of the pressure and flow from the arterial side of the AV fistula versus the pressure and flow that you are introducing from your sclerosant injection.
Answer by Mark Whiteley MS FRCS (Gen) FCPhleb on 20th June 2012

Q4 What level of liver dysfunction / cirrhosis (childs class I? II? III?) contraindicates using lidocaine in tumescent fluid? - Richard Mueller FCPhleb (New York, USA)


This is a fascinating question and one that is never cropped up in my many years of practice. I’ve never so far had to treat a patient with thermoablation with liver dysfunction or cirrhosis. If it did occur, I would consult with the patients hepatologist to see what limits they would be happy for. I would be very interested in anyone else’s experience in such patients.
Answer by Mark Whiteley MS FRCS (Gen) FCPhleb on 20th June 2012

Q5 What is your cutoff of reduced ABI in PAD for themoablation? Other than possible intolerance of post procedure compression, is there any solid rationale for excluding pad patients from thermoablation. Ideally fix arteries first, yes, but patients often decline pad procedures, have renal insufficiency, etc. - Richard Mueller FCPhleb (New York, USA)

This situation really only occurs in patients with leg ulcers. It is one of those situations where it is so uncommon in any other aspect that one needs to just take each patient in turn and think it through in first principles rather than have a blanket rule.

In terms of principles, firstly why has the patient presented? Clearly if they have severe PAD it is unlikely that they have turned up for their varicose veins to be treated. It is much more likely that they are complaining of claudication, rest pain or arterial ulceration all which need to be fixed before any venous surgery. In the few patients we have had who have venous eczema and very mild claudication, I would not use ABI as a cut-off as it can be artificially raised with atherosclerotic arteries. I do keep a record of ABI for medicolegal reasons and prefer to use the “Pole test” – i.e. at what height the leg can be elevated before the toes turned white.

In leg ulceration, it is often impossible to measure an ABI and so the clinical questions of whether the pain occurs when the leg is elevated or dependent coupled with the results of an arterial and venous duplex usually pointed to the correct treatment.

Finally, as a general principle, anyone who is having venous thermoablation with severe PAD is having it for non-cosmetic reasons. As such, the lesions that are being treated such as leg ulcers, LDS or leg ulceration are being caused by venous reflux from one of the truncal veins or perforators. One of the delights of using adequate thermoablation is that the relevant veins can be treated either by truncal ablation or TRLOP of the perforators with instant ablation and no requirement for any compression. Therefore the PAD is irrelevant to such antireflux treatment.

Answer by Mark Whiteley MS FRCS (Gen) FCPhleb on 20th June 2012

Q6 When aiming for a LEED of approx. 80 J/cm for a larger truncal vein per the GSV EVLA educational video, what size would be considered a larger vein? 7-10 mm diameter? larger? - Richard Mueller FCPhleb (New York, USA)

When considering the size of the vein, it is important to remember that “the size of the vein” is a diameter measurement performed by ultrasound. However the LEED that is required is actually determined by the mass of cells in the vein wall that we need to ablate. The diameter measurement will change depending whether the patient is standing, lying, warm or cold, and nervous or relaxed. The mass of cells in the vein wall however does not change with any of these factors. Therefore the “size of the vein wall” measured by ultrasound is only a surrogate measurement and therefore an estimation.

As such, until we have better techniques to evaluate this, one has to look at the ultrasound image and consider if the vein is large with a thick wall, is small with a thin wall, or looks small but due to contraction and therefore actually with a thick wall. What is clear is that if the vein is ever measured over 7 to 10 mm diameter, it is clearly a large vein and may even be larger but be contracting at the time of measurement. Once again, although many “experts” talk about what LEED to use with what diameter, this will only be an estimation into we can have a proper measurement of the mass of cells to be destroyed in the vein wall.

Answer by Mark Whiteley MS FRCS (Gen) FCPhleb on 20th June 2012

Q7 When performing the very rare truncal vein access via cutdown, does one have to ligate the distal segment after venotomy? Or do you just lift the vein and cannulate with needle without venotomy? Is it OK to hook and cutdown the SSV near the sural nerve at mid calf? I realize I may never have to do this. If ligating the distal vein, use 3-0 or 4-0 silk? - Richard Mueller FCPhleb (New York, USA)

This is a very good question but hopefully a very rare instance! There is quite a lot of evidence to suggest that it is haematoma that causes neovascularisation. As such anything that reduces haematoma in varicose vein surgery is a positive to reduce the risk of recurrent varicose veins. As such in this situation, I would always tie the distal segment to reduce any bruising and haematoma. However following the principles of RM Glass from Dublin (Ireland), I would always use a non-absorbable suture to ensure a permanent closure of the vein. I also want a suture that is inert as possible and least likely to cause tissue reaction. Therefore I always ligate my veins with polypropylene.
Answer by Mark Whiteley MS FRCS (Gen) FCPhleb on 20th June 2012

Q8 Beyond the marking function of duplex guided phlebectomy, do you ever use ultrasound in real time to help hook the vein if they don’t hook easily blindly? - Richard Mueller FCPhleb (New York, USA)

Yes. I was using this technique with ultrasound in theatre in 1998 even before we started performing endovenous surgery. I use the ultrasound not only to hook up any vein that I could not find with a phlebectomy hook blindly but also used it to plan incisions for the Small Saphenous Vein (SSV) (see: Minimally invasive technique for ligation and stripping of the small saphenous vein guided by intra-operative duplex ultrasound. MS Whiteley, G Lewis, JM Holdstock, C Smith, CS Harrison, CL McGuinness, BA Price. Surgeon 2006: 4; 6: 372-377)
Answer by Mark Whiteley MS FRCS (Gen) FCPhleb on 20th June 2012

Q9 Your vein depth approximate cutoff of 5 and 10 mm for safe thermoablation of varying size veins is very helpful practically. What size veins are safe to thermoablate between 5-10 mm from the skin? - Richard Mueller FCPhleb (New York, USA)

The problem with this question is that it reinforces a misunderstanding prevalent in endovenous surgical papers. When we measure the “size of a vein”, we are measuring the luminal diameter on ultrasound. Of course what we really want to know is the thickness of the vein wall. If the patient is cold and/or nervous, a large vein will be smaller. If the patient is warm and/or relaxed the same vein will appear bigger. However the mass of cells in the vein wall that need to be ablated and hence the inflammatory reaction that occurs from this ablation will be the same.
Once this is understood, then we understand that the “size of a vein” on ultrasound is only a surrogates measurement and therefore is an estimation of what we really want to know. As this is only an estimation, to start giving guidelines would be inappropriate. As such I would maintain that a substantial truncal vein should not be treated unless at least 10 mm deep and, if a smaller vein (when the patient is warm and relaxed) is slightly more superficial, I might consider it if I am convinced that the vein has a very thin wall. However at the moment we do not have the techniques accurate enough to measure what we wish to know nor the research available to give a hard and fast rule.
Answer by Mark Whiteley MS FRCS (Gen) FCPhleb on 20th June 2012

Q10 If a pigmented cord occurs after thermoablation, do you try to aspirate blood as a treatment? If so, at what time frame? Do you ever try hydroquinone cream in case there is a post inflammatory hyper pigmentation (I.e. melanin) component in addition to a hemosiderin component? - Richard Mueller FCPhleb (New York, USA)

A pigmented cord after thermoablation can only be due to one of two things.

The most common is an inadequate treatment which has allowed thrombus to accumulate in the lumen that has not been successfully ablated. The best treatment for this is to do the ablation properly in the first instance and then this will not occur. If blood can be aspirated, this is a sign that the ablation was unsuccessful and the operator’s technique needs to be looked at. In such a case, the blood liquefies after four weeks and can be aspirated, but the ablation will have to be re-performed several months later. If at that stage the lumen is very small and the vein scarred, and endovenous device might not be able to be passed up the vein and foam sclerotherapy might be needed instead.

The second reason is that the vein treated with thermoablation was too superficial, and the inflammatory process of the vein ablation is causing a reddish or brownish line. Once again the best way around this is to get it in the first place and to make sure that thermoablation is not performed on veins that are too superficial. If it does occur, the primary problem is an inflammatory one and hence any anti-inflammatory drugs such as aspirin will help settle down.

To date we have never had to try hydroquinone cream and I would wait to see studies before commenting on this use. It will clearly depend on what the cause of the pigmentation is as to whether we would expect this treatment to be successful.

Answer by Mark Whiteley MS FRCS (Gen) FCPhleb on 20th June 2012

Q11 For duplex guided phlebectomy of superficial truncal segments, are all segments safe to treat? Should mid to distal calf segments be avoided due to proximity of saphenous and sural nerves? And what about proximity of Gastroc veins and the SSV? - Richard Mueller FCPhleb (New York, USA)

This situation rarely occurs. True truncal veins run in their own fascia – the Great Saphenous Vein (GSV) has its own saphenous fascia (often called “the eye of Horus” since the advent of tumescent anaesthesia under ultrasound imaging) and the Small Saphenous Vein (SSV) similarly lies in a triangular fascia. Therefore unless the patient is very thin, these veins are not visible on the surface. Visible “superficial truncal segments” are usually anatomical variants due to the truncal vein having an atrophied segment and a superficial vein taking over the role to “bypass” that segment. Such segments can be seen on ultrasound to come out of the relevant fascia. The good news about this is that they do not run with either of the two nerves that rumbled the truncal veins.

On the rare occasions that the patient is slim enough to see such truncal veins, it is very uncommon to need to treat the distal Great Saphenous Vein (GSV) as the reflux within it is passive only (see the book “Understanding Venous Reflux – the cause of Varicose Veins and Venous Leg Ulcers“). As such, when the proximal vein has been successfully ablated, it is very uncommon that the distal Great Saphenous Vein (GSV) needs to be removed by phlebectomy. Unless there is an incompetent perforator continuing reflux within it during the active phase, the vein will often reduce in size with time and can be treated successfully with ultrasound guided foam sclerotherapy as it shrivels away.

The Small Saphenous Vein (SSV) reflux is in the active phase and once again, if the proximal end is ablated, the distal part will slowly shrivel away with time and should not need phlebectomy.

Answer by Mark Whiteley MS FRCS (Gen) FCPhleb on 20th June 2012

Q12 If one wanted to foam a distal truncal vein after EVLA ablation, after removing the fiber near the access site, can one use the same sheath and have the foam track retrograde from the sheath tip into the distal vein as it is blocked proximally (and helped with manual milking at skin level)? have you tried this? - Richard Mueller FCPhleb (New York, USA)

If I understand the question correctly, this is suggesting that ablation has occurred from the saphenofemoral junction in the Great Saphenous Vein (GSV), or the top of the Small Saphenous Vein (SSV) if treating this vein, all the way to the access sheath and then injecting foam sclerotherapy so that it will track down from this level distally in the truncal vein. If this is the situation, then no I have not tried this and I have not ever had reason to try to do this.
I don’t really think that foam is a primary treatment for an incompetent truncal vein, as it is very rare that a truncal vein is small enough to respond to foam sclerotherapy successfully. Therefore I would use thermoablation to the whole of the trunk that I would need to treat, with phlebectomy of any areas that are too superficial. If in the future there were clinical problems related to the distal truncal vein that was still incompetent, the chances are that it would be related to perforators feeding into the truncal vein to cause reflux and I would treat these with TRLOP (TRansLuminal Occlusion of Perforators).

Very rarely I have treated a distal GSV with foam sclerotherapy, months after performing ablation of the proximal section and having successfully treated the perforators, but still having some skin changes that are not improving. In these rare cases, duplex ultrasound usually shows a profusion of small veins under the damaged skin which are not suitable for anything that foam sclerotherapy. Injection of the remnant of the truncal vein under ultrasound control usually ablates both this remnant and also this network of veins, giving a satisfactory result.

As such, I cannot conceive of a situation where I would ablate a truncal vein and then immediately perform sclerotherapy of the distal section of the same vein. However I am always open to seeing new techniques if there is a good indication that I have missed.

Answer by Mark Whiteley MS FRCS (Gen) FCPhleb on 18th May 2012

Q13 If performing EVLA and foam sclerotherapy in the same session in the same truncal vein, is there any fear of tissue necrosis from sclerosant extravasation from laser vein wall perforations or if performing phlebectomy at the same sitting? - Richard Mueller FCPhleb (New York, USA)

This situation should not really occur. Firstly, considering laser vein wall perforations, it is unlikely that if you have ablated a truncal vein that you would then pass any significant amount of foam sclerotherapy up that area. If the vein is ablated, why would you be passing foam at the same section?  Of course if you used a radial firing laser, then perforations of the vein wall rarely occur.
Secondly, when performing foam sclerotherapy, eccentric compression should really be placed directly on the area within a minute or two of the injection to get the optimal result. Failure to do this increases the risk of blood tracking back into the vein and “sclerothrombus” which will give brown stains and a high chance of failure in the medium to long term. Therefore the situation of performing foam followed by phlebectomies where the foam might “leak and” should not occur.
Answer by Mark Whiteley MS FRCS (Gen) FCPhleb on 18th May 2012


Q15 For superficial truncal segments that are 3 mm in diameter, I presume another option is to thermoablate deep segments then use the same catheter to foam the superficial segments? - Richard Mueller FCPhleb (New York, USA)

Absolutely. In very thin walled veins that are typically 3 mm or less in diameter when the patient is relaxed and warm, foam sclerotherapy is an ideal option. It is certainly possible to thermoablate deep segments and then use foam sclerotherapy for the superficial segments. However if we are convinced that the vein is fully dilated, and has a maximum diameter of 3 mm, then the whole vein can be treated with foam sclerotherapy. The meta-analysis data would suggest that such veins have 100% closure at three years provided the technique has been performed correctly and excellent compression has been used post operatively.
Answer by Mark Whiteley MS FRCS (Gen) FCPhleb on 15th May 2012

Q16 If ablating an ulcer patient to the ankle, why not access at the ankle? - Richard Mueller FCPhleb (New York, USA)

Access at the ankle is fully acceptable provided there is a good entry point. It is often easier than a retrograde passage of the catheter which can get caught up in valves, even if they are incompetent.
Answer by Mark Whiteley MS FRCS (Gen) FCPhleb on 15th May 2012

Q17 Is there any advantage to a 2nd access below knee for a retrograde ablation segment? - Richard Mueller FCPhleb (New York, USA)

I have often performed a proximal ablation from the knee to groin, and then a second ablation from the same entry point below the knee, but passing the catheter down to the ankle in a retrograde fashion. I think this is a very useful technique particularly if the ulcer prevents easy access into the Great Saphenous Vein (GSV) or Small Saphenous Vein (SSV) distally. However tumescence is often a problem under an ulcer and therefore one has to be very careful with pain. This is one of the reasons I am very interested in the Sapheon (Venaseal) product and think that this may be an ideal place to use it. Certainly foam sclerotherapy is disappointing in the very large truncal veins in this area, although very useful in the smaller and more profuse veins under an ulcer.
Answer by Mark Whiteley MS FRCS (Gen) FCPhleb on 15th May 2012

Q18 Is your LEED target 60-70 j/cm for SSV? - Richard Mueller FCPhleb (New York, USA)

Generally the answer to this is yes. However, although I have not researched it yet, I am a little concerned that the Small Saphenous Vein (SSV) might be a slightly thicker wall and as such tend to aim for an LEED of 70 to 80 J per centimetre. I cannot give good evidence for this, but certainly in patients with oedematous legs, the Small Saphenous Vein (SSV) appears to be thicker and therefore requires this extra energy to ablate it.
Answer by Mark Whiteley MS FRCS (Gen) FCPhleb on 15th May 2012

Q19 If one wants to stage phlebectomy of branch varicosities or hidden tributaries (or superficial segments of truncal veins), how long on average does one have, in days, before varicose branches/tribs might clot off and become phlebitic, preventing ultrasound guided phlebectomy? - Richard Mueller FCPhleb (New York, USA)

We often stage phlebectomies after truncal ablation. I think it is less important to give an average time of treatment, rather than an understanding of what is going on. If the branch varicosities or hidden tributaries are small and not too varicose, then it is likely that they will be okay even if the phlebectomy is one or two weeks later. However if the varicose branches or tributaries are large, then it is much more likely that thrombophlebitis will occur, resulting in phlebitic vein. Therefore in general, when we perform stage phlebectomies, we try to do it within one week and make sure that the patients wear a graduated pressure stocking day and night on the affected leg until the time of the second surgery. If the veins are very varicose to enlarged, and are at risk, we will try to do this earlier. If they are not very varicose, then we are happy to leave it for longer. There is no set timing.
Answer by Mark Whiteley MS FRCS (Gen) FCPhleb on 15th May 2012

Q20 Would thermoblation of 3-5 mm truncal veins be likely to cause a painful cord if 3-4 mm under the skin? - Richard Mueller FCPhleb (New York, USA)

I don’t think that the problem is the size of the truncal vein as this can change with many factors (such as cold, fear etc). Once the truncal vein has been treated with thermoablation, there is a mass of inflamed tissue. Regardless of whether tumescence has been used, it will disappear before the inflammation does. If there is a 3 to 5 mm vein inflamed to only 3 to 4 mm under the skin, it is going to cause tenderness, a hard structure to feel and probably red and then brown stains of the skin from the inflammation. My preference would be to thermoablate the deeper sections of the vein, and perform a phlebectomy of any section of truncal vein within 5 mm (and maybe even up to 10 mm in big veins) of the skin.
Answer by Mark Whiteley MS FRCS (Gen) FCPhleb on 15th May 2012

Q21 For truncal laser ablation, do you use a uniform LEED at proximal/mid/distal segments? Or only when vein diameter varies? An older Min article I trained with advised 140/70/45 j/cm, quite a large gradient, but I have always used higher LEED proximally, with great results for years with a bare fiber and 810 nm - Richard Mueller FCPhleb (New York, USA)

When Robert Min first started lecturing on EVLA, he was using a discontinuous pullback, stopping every centimetre to fire the laser. That caused considerable bruising (ecchymosis). That technique has been overtaken by the smooth pullback which both clinically shows better results and our in vitro experiments show this provides a more uniform thermal damage. Provided you are reaching a minimum of a LEED of 60 J per centimetre for a normal size Great Saphenous Vein (and probably 70 J per centimetre for a larger one) then I cannot see any reason for a gradient. If you are successfully completely ablating a vein with an appropriate LEED, it seems to be only gilding the lily to have different LEEDs for different parts of the same vein. This would only make sense if your premise is that the proximal GSV has a significantly thicker wall than the mid thigh or knee GSV, and therefore needs a greater LEED.
My clinic is now performed over 16,000 truncal vein ablations since 1999 and we have only ever found three veins that have not completely closed. Therefore provided an adequate LEED is used the whole way along the vein, this is to be no reason at all to over treat the proximal section.
Answer by Mark Whiteley MS FRCS (Gen) FCPhleb on 10th May 2012

Q22 I take it that you still aim for a LEED of 60-90 j/cm even with 1470nm laser + radial fiber, and 10W, rather than 5-6W and 30-50 j/cm? - Richard Mueller FCPhleb (New York, USA)

Yes. All of our research at The Whiteley Clinic over the last decade has shown that for thermoablation, whether laser or radiofrequency, a LEED of 60 to 90 J per centimetre is required for a Great Saphenous Vein (GSV) – and potentially at the higher end of this for very thick walled veins. It is illogical to try and say that a different wavelength changes this, when we find exactly the same results with radiofrequency. It is therefore a function of the power transmitted into the vein per centimetre (provided it is transmitted in a way to let it spread through the vein wall).

This is discussed in more detail in our next book that is shortly to be released as the second book in The College of Phlebology’s series.

Answer by Mark Whiteley MS FRCS (Gen) FCPhleb on 10th May 2012

Q23 Is there any rationale for superiority of applying tumescent from proximal to distal rather than starting at the level of the sheath? - Richard Mueller FCPhleb (New York, USA)

The rationale for starting tumescence from proximally is that this is the first area of vein that gets heated when the thermoablation starts, and so if the tumescence is also started here, the local anaesthetic has the longest possible time to work before thermoablation commences.

I do not feel very strongly that there is an awful lot of difference where the tumescence is started, provided it is positioned correctly and enough is given, but it seems illogical to start at the sheath and finish at the groin, when the heating starts at the groin and finishes at the sheath.

Answer by Mark Whiteley MS FRCS (Gen) FCPhleb on 10th May 2012

Q24 What energy dosing/pullback do you use specifically for TRLOP with a radial fiber/1470 nm laser of perforators? - Richard Mueller FCPhleb (New York, USA)

For the TRLOP technique, the perforator is cannulated and so the tip of the laser lies within the perforator veins lumen. Tumescence is placed in the vein and therefore we can use exactly the same physics as if it were a small diameter (and therefore thin-walled) Great Saphenous Vein (GSV). Using the standard radial fibre (not the radial slim) I use 10W. The pullback is determined purely by the length of vein that has been cannulated, but should equate to a LEED of 60 to 90 J per centimetre. There really is no difference in the physics of treating a short vein.
Answer by Mark Whiteley MS FRCS (Gen) FCPhleb on 10th May 2012

Q25 For superficial truncal veins and accessory truncal veins, what depth from skin is your cutoff for avoiding laser for fear of producing a hard pigmented cord? Some have advised 4 mm to me - sometimes the vein is only focally closer than 4 mm to the skin and I feel I can still laser but just do a faster pullback at the focally more superficial location. And for such veins, other than the foaming or stripping option, do you advise ultrasound guided phlebectomy? Is that ok for accessory veins and even superficial GSV or SSV, or do you reserve phlebectomy only to branch varicosities? - Richard Mueller FCPhleb (New York, USA)

I always feel safe to perform thermoablation when the vein is more than a centimetre from the skin. I do not think there is a magic number which is safe at a distance less than this, as it depends on the mass of the vein. If you have a very small vein which you push deeper with tumescence, and then ablate with thermoablation, when the tumescence wears off the inflamed remnant of the vein will probably not affect the skin even if it is only 4 mm deep. However exactly the same position with a large vein will end up with a very large inflammatory tubular mass which was previously vein, and which will affect all tissue including skin to a larger radius when the tumescence disappears.

Therefore in our practice, we would ablate the sections of the truncal vein deeper than 1 cm, and perform duplex guided phlebectomy for sections getting closer to the skin. We may well have two or three entry points for one truncal vein in such cases.

We would never strip veins and do not use foam sclerotherapy for any vein greater than 3 mm diameter unless there is an overwhelming reason to do so.

The same as above applies to the anterior accessory saphenous vein. I would use thermoablation for the trunk that is subfascial, starting at the point where the trunk perforate through the superficial fascia. I then perform phlebectomies for the subcutaneous part of this vein if varicose, or foam sclerotherapy if less than 3 mm, refluxing and feeding into thread veins.

Answer by Mark Whiteley MS FRCS (Gen) FCPhleb on 5th May 2012