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Varicose Veins: Innovations in Sclerotherapy Techniques

Sclerotherapy is the preferred method of treatment for small and medium varicose veins and telangiectasia. According to an international consensus document, venous ultrasound technicians should have a solid foundation in venous reflux testing technique and venous anatomy in order to direct a patient to proper treatment. Starting from the diagnosis and moving onto treatment planning and execution, the keys to sclerotherapy efficacy and safety are proper technique and anatomic knowledge. A European guideline for sclerotherapy defines the objective of injection sclerotherapy as inducing inflammation in the vein wall to cause the vessel to contract, fibrose, and finally become a connective tissue-like cord. This is to be achieved with the least amount of sclerosant, with immediate ambulation and normal activities of daily living.

Varicose veins are more than just a cosmetic problem. They can lead to leg pain, leg fatigue, restlessness, leg heaviness, throbbing, cramping, muscle tiredness, and ankle edema, especially after long periods of standing or sitting. Over the past three decades, sclerotherapy has been shown to be a safe, cost-effective non-surgical treatment for varicose veins and telangiectatic leg veins. New sclerotherapy techniques and innovations continue to improve the efficacy and safety of this treatment.

Varicose veins are a common problem in the United States and in the Western Hemisphere. It is estimated that at least 25 million people in the United States are affected by this medical condition. Varicositis, a condition attributed to a malfunction of the valves within the veins, is often the cause of varicose vein. It allows the blood to flow in a reverse direction, which is the cause of the pooling of the blood within the lower extremities and the eventual distension of the veins.

Overview of Varicose Veins

Venous insufficiency is addressed with various treatments depending on the severity of the condition. Regular exercise, leg elevation, weight loss, and avoiding prolonged standing can help to alleviate the symptoms of mild venous insufficiency. For more severe cases, there is a range of medical treatments and vein procedures that have high success rates for removing varicose veins and resolving chronic venous insufficiency. These procedures include but are not limited to: vein ligation and stripping, ambulatory phlebectomy, and endovenous ablation. All of the aforementioned procedures have potential side effects and/or complications and usually have downtime periods where the patient must refrain from performing normal daily activities. A new innovative procedure for the treatment of various vein problems is ultrasound-guided foam sclerotherapy. This is a minimally invasive procedure with little downtime and has been found to be effective in the treatment of various vein problems. This procedure will be the primary focus of this website.

Varicose veins occur as a result of venous insufficiency which is a condition where the venous wall and/or valves in the leg veins are not working effectively, making it difficult for blood to be returned to the heart from the legs. Normally veins return oxygen-poor blood to the heart from the body. When the veins in the legs do not return blood to the heart effectively, the blood pools in the leg veins. This can lead to varicose veins and aching discomfort in the best case scenario and can progress to more serious conditions in the worst case scenario. The cause of venous insufficiency is primarily attributed to prolonged standing and increased abdominal pressure. The effects of prolonged standing on the leg veins can cause damage to the vein wall while the effects of increased abdominal pressure can cause a weakening of the valves thus leading to venous insufficiency.

Varicose veins are dilated, tortuous, elongated superficial veins that are usually seen in the legs. They are considered a cosmetic problem for most patients but can also cause aching pain and discomfort, and in some cases more severe complications such as phlebitis, ankle edema, and skin changes including ulceration. The estimated prevalence of varicose veins is about 25% in women and 15% in men. This means that there are about 55 million people in the United States with varicose veins, 41 million with vein changes, and 20 million with associated skin changes. The socioeconomic impact of varicose veins is also significant as it is estimated that 2 million workdays are lost in the USA per year as a result of chronic venous insufficiency.

Importance of Sclerotherapy Techniques

Sclerotherapy is a simple, effective method of treating varicose and spider veins. A painless solution is injected directly into the vein. This causes the vein to collapse and fade over a period of weeks to months. It is a less invasive and expensive alternative to vein surgery. Sclerotherapy also can relieve symptoms caused by varicose veins and prevent complications of this condition. This includes venous ulcers and blood clots. Despite the effectiveness of sclerotherapy in treating small varicose veins, it has been less successful in treating larger veins. Usually, 3-6 treatments are required to treat the same area with only a 30-70% resolution. This requires many needle sticks and repeat visits with weeks of wearing support hose. In addition, occurring with greater frequency in larger veins are side effects such as staining of the skin and inflammation. An alternative to traditional sclerotherapy involves the use of ultrasonography to guide the injection of a solution. In a study comparing the two methods, patients who underwent ultrasound-guided sclerotherapy had a better resolution with fewer side effects. This innovation in technique has provided a more effective treatment with minimal complications. A more recent innovation in sclerotherapy involves the use of a foam preparation of sclerosant. This has been found to be more effective than liquid sclerosant in treating larger varicose veins. In a double-blind trial comparing the two methods, 37% of the foam-treated veins were completely collapsed whereas only 17% of the liquid-treated veins had the same outcome. Another study reported an 81% closure rate in foam-treated veins as opposed to 46% in liquid-treated veins. This method of sclerotherapy is proving to be very promising.

Traditional Sclerotherapy Techniques

Although liquid agents are effective, it can be difficult to see if the solution is filling the entire lumen of the vein. This may lead to inadequate or incomplete treatment. It can sometimes be hard to determine whether a vein is reticular or telangiectatic. Reticular veins can be injected with any of the liquid agents, while telangiectatic veins are best treated with hypertonic saline. Telangiectatic veins are often hard to detect and are usually left behind after treatment, as they are very difficult to inject without extravasation.

The solution used is usually in liquid form and is injected with a very fine needle. Agent strength is varied, with different agents being suitable for different-sized veins. Hypertonic saline was originally used to treat veins; however, more effective agents have been developed. A popular choice among phlebologists is STS (sodium tetradecyl sulfate). STS has been preferred due to its effectiveness and it being less painful than hypertonic saline.

Sclerotherapy is considered to be an easy and cost-effective method of treating varicose veins. Sclerotherapy is performed by injecting a solution into the vein. The solution irritates the lining of the blood vessel, causing it to swell and the blood to clot. Over time, the vessel turns into scar tissue that fades from view. The injection site is numbed with a local anesthetic. No stitches are required. Injection of the solution can cause mild discomfort.

Injection of Sclerosing Agents

Injection of sclerosing agents is the crux of sclerotherapy. The choice of syringe, needle, and the sclerosant itself are paramount to success. For the treatment of smaller varicose and reticular veins, 23-30 gauge needles are recommended. Larger veins usually require a 21 gauge needle. Compression of the vein at its most proximal point can prevent painful extravasation of the sclerosant, thus emptying the vein of blood and enabling better visualization. There are numerous sclerosing agents available at this time. Sodium tetradecyl sulfate (STD) is available in different concentrations and is the most commonly used around the world. Fibrovein, aethoxysclerol, and ethanolamine are widely used in Europe. A detergent sclerosant, STD works by having a direct toxic effect on the venous endothelium at the site of contact. It is particularly useful for larger veins due to its liquid or low mousse form. Aethoxysclerol is available in different concentrations and is useful for a variety of veins in different parts of the body. Fibrovein is commonly used in a foam form and works in a similar manner to STD. The choice of sclerosant is often based on physician preference and availability.

Compression Therapy

Encapsulated microfoam has been considered an ideal sclerosing agent as the foam itself acts as an effective compressive device. This was tested in a randomized controlled trial comparing polidocanol microfoam compression sclerotherapy with and without bandaging for varicose veins. At the end of treatment, patients were assessed by ultrasound for residual non-refluxing veins (residual veins are one of the markers for treatment failure), and it was found that those with adequate compression using multilayer bandaging had significantly fewer residual veins than those without the bandaging. This suggested that while foam is a very effective treatment, it has to be combined with adequate compressive therapy to be optimally effective.

There is a great deal of evidence to support the concept that the more effective compression is in the immediate post-treatment period, and the less mobile the patient is, the better the results of sclerotherapy and the shorter the time needed for compression. This has led to much research into ways of enhancing the effects of compression therapy and reducing the time of compression.

As we have discussed, traditional compression sclerotherapy involves an initial period of downtime, where the patient is instructed to rest with legs elevated for an extended period of time. This is followed by several weeks in compression stockings. This method provides satisfactory results, both in clinical and cosmetic terms, but can be unacceptable to the patient. This has led to patients failing to comply with their compression or not being prepared to undertake treatment at all.

Foam Sclerotherapy

There are a number of advantages to traditional liquid sclerotherapy including low viscosity of sclerosant and improved visualization on ultrasound guidance. Nevertheless, Myers describes foam sclerotherapy as an effective method of treating all forms of varicosity. It is best utilized for large saphenous veins, recurrent varicose veins and difficult to treat and tortuous smaller varicose veins. He also suggests that the location of vein beneath the skin is irrelevant due to the use of foam which is a contentious statement. The evidence for the etiology and pathology of varicose veins and chronic venous disease leads to the conclusion that foam sclerotherapy best treats veins that have arisen from saphenous vein reflux and incompetence. This is because the foam can be easily manipulated into the saphenous vein followed by manual dispersion of the sclerosant in order to treat a higher portion of the vein. High GSV and SSV ligation and endovenous therapies are generally regarded as the best treatment for varicose veins and foam sclerotherapy has no role in these procedures. Anatomically, foam sclerotherapy is most suitable for superficial veins that are either connected or perforating to the saphenous vein.

In hindsight, the drawbacks of the paper are that the author infers that traditional liquid sclerotherapy is a suboptimal treatment for varicose veins. This reflects his biased perspective as an international educator of the phlebological community and experienced foam sclerotherapist. Additionally, the article does not provide critical examination of the current evidence or argue the limitations of foam sclerotherapy.

A novel method of sclerotherapy involves the creation of a sclerosant agent foam. The foam is produced by a patented mixing system that rapidly converts the liquid form of sclerosant to foam form. The foam is applied as a dental alginate impression of the limb and then covered with a layer of bandage, producing a constant, gradual pressure. Studies have suggested that foam sclerotherapy is an effective means of treating varicose veins and a useful tool in the management of recurrent varicose veins. The paper by Myers brings together the collective international experience with foam sclerotherapy in an attempt to standardize techniques and provide a clear set of guidelines based on the collective evidence.

Innovations in Sclerotherapy Techniques

Ultrasound-Guided Sclerotherapy (UGS) is performed in the upright position under continuous ultrasound guidance.

Laser-Guided Sclerotherapy (LGS) involves the use of a small laser fiber directly applied to the reticular or larger feeder veins, followed by an injection of a sclerosant. The laser heats the vein, causing it to shrink and seal shut, thus reducing the risk of regurgitation of blood into the vein. This form of sclerotherapy has proved to be particularly successful in treating larger feeder veins and has reduced the need for more invasive surgical techniques.

Sclerotherapy has been used to treat varicose veins for over 50 years. It has been shown to be the most effective method of treating spider and small varicose veins and also has been successful when treating larger varicose veins. Sclerotherapy has advantages over surgery for treating smaller varicose veins due to its lower risks, lower cost, and a shorter recovery period. The newer forms of this technique have been introduced over the last decade and have become key tools in treating veins.

Laser-Guided Sclerotherapy

VNUS Closure uses a catheter in a slightly different way to eliminate the saphenous vein. The patient is given Paracast or peri-catheter tumescent anesthesia. The skin is marked two centimeters distal to the saphenofemoral junction. An 18-gauge needle is inserted 2 centimeters distal to the saphenofemoral junction and is directed towards the greater saphenous vein at an angle of 30-45 degrees with the skin and 30-45 degrees in a lateral to medial direction to penetrate Blue Line, 2 cm distal to the saphenofemoral junction. A stab incision is made over the needle. Blue Line is a sonographic insertion point to correctly position the introducer sheath. The insertion angle allows for puckering of the soft tissue, which is called the tenting effect and aids in visualization of the tip of the needle. Intraimaging is very important in the identification of the saphenofemoral junction and the needle. We seek to have the needle enter deep to the fascial plane and cross the greater saphenous vein closer to Kong’s septum. Inferior to superior Kong’s septal anatomy demonstrates a somewhat “Z” shaped pattern of fibrous tissue creating an interface between the greater saphenous vein and the deep system. We go across the greater saphenous vein at its nearest point to the deep system or when the greater saphenous vein is 1.5-2 cm distal to the saphenofemoral junction. This reduces the risk of accidental puncture of the deep system and increases the time the catheter remains inside of the vein, which allows for a more effective and uniform treatment. When the needle is correctly positioned, the assistant will pull the tail of the needle out of the skin to be parallel to the vein. The needle is removed from the trochar and a 0.018″ Brockenbrough needle (or Nitinol wire) is advanced through the trochar sheath and the trochar sheath and anvil are removed. A nick is made in the tail of the needle and a loop of suture is placed through the needle tail. The purpose of the loop is to retract the vein and maintain contact between the vein and the eventual closure catheter, which results in a more effective vein treatment. The suture wire is retrieved from the skin and the needle and sheath are removed, leaving the wire in place to guide the closure catheter. After the introducer sheath is positioned over the wire with the wire against one side of the vein to allow for easier crossing back and forth, the closure catheter is advanced with Seldinger technique to the distal end of the vein. The long-length closure is performed by multiple overlaps of the 68 cm closure catheter to treat the entire vein in one session. This is logistically easier for the physician and is more appealing to patients due to the decrease in post-procedure pain from local anesthetic fascial injections and subsequent closure treatments. When the closure catheter is in the distal end of the vein, a pullback of 7 cm/sec is used for a total of 140 J/cm, which is the amount of energy required for collapse of the vein without perforation or stenosis of the lumen. The catheter is then pulled back every 7 cm with 40-60 J/cm to a maximum of 10 cm distal to the saphenofemoral junction. Usually, about 5-10 closure treatments are used between sessions at the same site to completely obliterate the vein. Patients usually resume normal activity and discomfort is minimal compared to previous vein treatments.

Ultrasound-Guided Sclerotherapy

An alternative, more advanced treatment mechanism uses specially designed catheter delivery systems to administer the sclerosant foam under controlled conditions to only the precise areas required, while avoiding the need for any mechanical damage to the vein. This catheter-based foam sclerotherapy has the potential to greatly optimize the treatment of larger varicose veins but is currently limited by availability of the special catheters and governing regulations regarding the safety of using the foam sclerosant in veins.

A modified form of USGS has been developed to treat larger varicose veins with the intent of avoiding surgery. This involves insertion of a catheter into one of the main superficial veins to be treated. The vein is then lined with the catheter, and the sclerosant injected as the catheter is withdrawn. The catheter is then used to mechanically damage the vein wall, causing a chemical phlebitis to occur. This method can be effective; however, it is aggressive and often results in a larger volume of post-treatment pain and discomfort.

The skill involved in successfully performing USGS lies in the ability of the operator to visualize all potential reflux points and abnormal veins while concurrently injecting the sclerosant to give the desired chemical and physical effect in the vein. Measures of success for this procedure should be based on how well the treated veins would have responded to surgical intervention.

Ultrasound guided sclerotherapy (USGS) has been around for over 10 years. Modern advancements have made this a treatment that is both widely accessible and effective. Basic USGS involves the use of ultrasound to locate the abnormal veins. A small needle is then inserted and the sclerosant injected, causing the vein to collapse. Using only the basic USGS technique, results are limited and probably less successful than a well-performed treatment using standard injection sclerotherapy.

Endovenous Laser Ablation

The catheter is advanced up the leg to just below the groin. This stage is crucial. It is where micropulses of optical energy are delivered to the vein wall, causing it to heat up and denature, or breakdown, the collagen in the wall. This leads to vein wall shrinkage and the closing and sealing of the vein. If the catheter is placed too deeply, energy delivery may heat the saphenous nerve, causing paraesthesia in the thigh (pins and needles or numbness). If it is misplaced, energy delivery may cause bruising or hematoma by acting on the skin or deeper vessels. A skilled operator will avoid these complications. A study of 1000 EVLA procedures reported a 0.1% instance of Deep Vein Thrombosis (DVT).

EVLA is usually performed under local anaesthetic. Using ultrasound, the vein is located and a small area of skin is anaesthetized with local anaesthetic. A needle is then inserted through the skin and into the vein. A wire is passed through the needle and the needle is removed, leaving the wire in place. A small incision is made through the skin and a catheter is inserted into the vein over the wire. The wire is then removed.

With the first clinical use of endovenous laser treatment (EVLT) reported in 1999, this is a relatively new procedure that is rapidly gaining momentum in the treatment of varicose veins. It is designed for the treatment of larger, more proximal, refluxing saphenous veins. There are a few different types and wavelengths of laser, but most use a diode laser with either an 810 nm or 980 nm wavelength catheter.

Radiofrequency Ablation

Several studies have shown RFA to be effective, with up to 92% of treated veins remaining sealed after 1 year and 84% after 18 months. This seems to compare favorably with the 80-90% success rates reported for surgery in the same time frame. There are a number of potential reasons for choosing RFA over surgery. The minimally invasive nature of the procedure means it can be carried out under local anesthetic or light sedation, and the patient can usually return to normal activity the following day. This compares very well with the downtime and recovery associated with vein stripping or ligation/phlebectomy. RFA can also be used on patients who have health issues that would make them unsuitable for surgery. This is an additional benefit over some other minimally invasive techniques, which may not be an option for patients who have impaired pulmonary or cardiovascular function.

Radiofrequency ablation is a new and promising technique in the treatment of saphenous vein reflux. The principle is simple: the vein is punctured with a needle and a catheter is passed up the vein. Once in place, the catheter is used to deliver radiofrequency energy to the vein wall. This causes the collagen in the vein wall to shrink and the vein to close. The procedure is normally carried out using a local anesthetic and under ultrasound guidance. The patient usually requires some form of compression for a period of time after the procedure, and there may be some skin discoloration over the vein in the weeks following treatment.

Benefits and Considerations

Foam sclerotherapy is a new technique that has been used extensively in the treatment of varicose veins in Australia and overseas. It is an extension of the conventional method, whereby a foamed sclerotherapy solution is injected into the vein. It has been shown to be more effective than the conventional method but may have potentially more complications. Foamed sclerotherapy is best used for larger veins and requires a skillful technique.

The newer techniques of Ultrasound Guided Sclerotherapy (UGS) and Foam Sclerotherapy have improved the efficacy of injecting the solution into the correct place. UGS involves the use of ultrasound to visualize the underlying varicose veins. This enables a more accurate and precise injection of the solution into the vein. With traditional sclerotherapy, injections are given blindly and often the vein cannot be seen to fill with the solution.

Sclerotherapy is an ideal treatment for varicose veins due to its minimally invasive nature. The sclerotherapy technique is not a new treatment for varicose veins. It has been used for over 150 years in the treatment of these unsightly veins. This technique involves the injection of a solution into the vein. This solution irritates the lining of the vein, causing it to swell up and the blood to clot. Over a period of weeks, the vein turns into scar tissue and fades.

Reduced Pain and Discomfort

Injection compression sclerotherapy can be performed for reticular and telangiectatic leg veins, and larger varicose veins, using a local anaesthetic at the site of the larger veins. Tumescent local anaesthesia is also effective, although it is more time-consuming and expensive. With these forms of anaesthesia, patients can determine whether there has been a treatment benefit as compared with other methods, because their veins will cause noticeably less or no pain and discomfort. It is well recognised that using general or regional anaesthetic for vein surgery can lead to patients having unrealistic expectations as to what the surgery will achieve, compared with the risk of significant postoperative pain and discomfort. Anaesthetic methods for treating veins are safer and are more likely to provide patients with long-term symptomatic relief.

In the case of sclerotherapy for leg telangiectasia, it has been estimated that between 10-25% of patients experience pain or discomfort in the form of burning, itching or cramping after injection. This can last for several hours to several days. Treating larger varicose veins with foam sclerotherapy or RFA often causes more post-procedural pain than with smaller veins or telangiectasia. Post-treatment pain can lead to a number of undesirable sequelae such as lost time from work, chronic pain syndromes, or the use of prescription pain medications. In extreme cases, it can sour a patient’s perception about the treatment or the physician, and dissuade them from seeking further treatment of a chronic or potentially debilitating condition.

The second major benefit is the fact that newer sclerotherapy techniques can significantly decrease or eliminate patient discomfort. Before I discuss this in further detail, it must be realized that pain is quite a subjective matter. What one person feels is a mild discomfort, another may feel is intolerable pain. This is why the advertisement of virtually painless procedures is important. Physicians who can project a sense of confidence that a patient will not suffer needlessly from a medical treatment will be much more likely to gain patient compliance.

Minimally Invasive Procedures

Thermal ablation has become an effective, minimally invasive option for treating superficial venous reflux. With recent advances in micro-catheter technology, vein access is achieved through a small entry point that requires no stitches. The procedure is performed using either the VNUS Closure™ or the EVLT™ system. Both use an electrical current or laser energy to heat and close the affected vein. These procedures are done on an outpatient basis, in an office setting. Following the procedure, patients are encouraged to walk and to resume normal activities. In fact, activity has been shown to improve patient outcomes in these procedures. Most patients report an improvement in their symptoms within 1-2 weeks. Though there can be some initial bruising or discomfort, the cosmetic results with these procedures are superior to vein ligation and stripping. These procedures have a 90-95% closure rate of the treated vein and have shown lasting improvement of symptoms over 2-5 years. A disadvantage of these procedures is the need for pre-authorization from insurance companies. While there are a variety of methods to heat and close damaged veins, the VNUS and EVLT systems have the most data supporting their efficacy and safety.

Faster Recovery Time

Patients undergoing any medical procedure are often concerned with the length of time necessary for recovery. As a result, inquiring about sclerotherapy, the patient will often ask similar questions because they wish to know if the treatment will result in time off work or undesirable limitations such as the need for assistance with care for their children. A randomized, double-blind study recently compared recovery times for two treatments of patients with superficial varicose veins. The study showed that recovery time, defined as time to return to normal activities, was faster in the sclerotherapy group. This study and others have shown the recovery time following sclerotherapy to be consistently fast for a variety of patients. This is in part due to the fact that the procedure is minimally invasive and does not require the extensive recovery associated with surgical stripping. Additionally, patients are encouraged to walk immediately after the procedure to prevent deep vein thrombosis. Post-procedure compression and ambulation have been shown to significantly decrease the incidence of DVT and will be discussed in further detail later. This combination of factors allows patients to resume normal activity in a relatively short period of time, making sclerotherapy a convenient option for patients with busy lifestyles.

Potential Risks and Complications

Anaphylactic reactions to sclerosing drugs are extremely rare, since they are highly irritant to the vein and usually cause immediate pain and spasm of the respiratory system which prevents systemic absorption. However, a severe allergy may cause hives and itching over the body and may even be life-threatening. The systemic toxicity of a sclerosing drug causes central nervous system disturbances in the form of headache, nausea, dizziness, visual disturbances, or rarely a brief generalized seizure. This toxicity may also cause minor myocardial damage with release of the enzyme troponin, although this has no long-term impact on the patient’s health. High dose or use of inappropriate drugs can cause phlebitis defined as inflammation of a vein that causes pain, redness and hardening at the injection site. This is a benign condition that usually resolves with no specific treatment. The most serious complication is deep vein thrombosis and/or pulmonary embolus, but there is no evidence to suggest an increased incidence of these conditions in patients of the appropriate age for treatment of varicose veins.

In contrast to the potential risks described above, the complications of sclerotherapy are very easy to detect since they cause immediate pain and/or visible effects. However, this is not to say that they are more serious or have more long-term implications. Spilling of the sclerosant from the vein can cause skin ulceration or “track” marks. Ischaemic injury from sclerosant being injected into a perivenous or intrafascial space is a theoretical but very rare complication.

Unintentional arterial injection may occur if the vein being injected is very close to an artery. This may result in paraesthesia or other neurological symptoms. Although dramatic arterial injury is rare, it has been reported and should be considered a serious complication. Any solution or foam may also cause visual disturbances due to retinal damage, or migraine in susceptible individuals. Simulation of deep vein thrombosis or paradoxical embolus. A technique that involves closing vein mucothrombosis, or emptying the vein of blood and refilling with sclerosant/thermal energy has certain theoretical risks that are difficult to assess. Because thrombi often have no symptoms or long-term effects, the possible creation of pain and swelling from thrombophlebitis or an increased incidence of silent pulmonary embolus are difficult to detect. High ligation and stripping, long considered the gold standard for treatment of great saphenous vein and associated varicose veins, has its own list of perioperative complications.

There are several potential complications that may occur with sclerotherapy and endovenous chemical or medical ablation of varicose veins. The following is a list of potential side effects and complications.

This black and white X-ray photograph shows the therapy of a varicose vein in the leg using a medical adhesive. After disconnection of the refluxing great saphenous vein (GSV) at the top of the image, the catheter is positioned in the GSV via an access point distally. Beginning at the top of the image, medical adhesive is injected as the catheter is pulled out in 5-7 mm increments. The blue dye around the vein in the middle of the image is the adhesive spreading into a tributary varicose vein.

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