CLaCS or sclerotherapy: which is better for spider veins

There is no universally best method for treating spider veins. If the vessel is accessible for precise puncture, sclerotherapy is often sufficient. CLaCS may be preferable for very fine spider veins, difficult access with a needle, a tendency toward matting, or the recurrence of spider veins after sclerotherapy. The choice is made after an examination and vein duplex ultrasound: a spider vein visible on the skin may be fed by reflux in a larger vein.

I have been practicing vascular surgery since 2019. I perform micro- and foam sclerotherapy, Echo-Foam, CLaCS, EVLA with a Biolitec laser, miniphlebectomy, and vein duplex ultrasound. This article discusses spider veins and why these methods do not always need to be treated as alternatives.

What sclerotherapy and CLaCS actually treat

Spider veins, or telangiectasias, appear as red, purple, or bluish lines and small networks. They may be an isolated cosmetic manifestation or may receive blood from a larger feeder vein. Therefore, treating only the visible area is sometimes insufficient.

During sclerotherapy, I inject a sclerosant into the vessel. It damages the inner lining of the vein, after which the vessel gradually closes and becomes less visible. Microsclerotherapy is used for small superficial vessels. Echo-Foam can be used for vessels of a different caliber and for feeder veins if indicated by the ultrasound and examination findings.

CLaCS combines a cryolaser with sclerotherapy for spider veins. The laser acts on the vessel through the skin, while the sclerosant is injected into the feeder vein. Cryocooling reduces discomfort and protects the skin during the laser stage. With CLaCS, spider veins are not «removed through punctures». If protruding subcutaneous branches need to be removed through small punctures, this is miniphlebectomy, not CLaCS.

Both methods exclude unwanted vessels from the bloodstream, but they affect them in different ways. Therefore, in some cases it is reasonable to start with sclerotherapy, while in others CLaCS offers more options for treating a fine vascular network.

When conventional sclerotherapy is sufficient

Conventional microsclerotherapy is suitable when the vessel is clearly visible and accessible for medication injection. This may be a single spider vein, a small group of vessels, or a network where the physician can control the position of the needle and the distribution of the sclerosant.

The following features support choosing sclerotherapy:

• the vessel has a sufficient diameter for safe medication injection;
• the vascular network is clearly visible;
• there is no significant feeder reflux requiring a different approach;
• the spider veins are not located near areas where laser treatment is undesirable;
• the patient is suitable for a method without a laser stage.

The advantage of sclerotherapy is its precise treatment of the vessel. Sensations are often described as brief tingling or burning at the injection site, but individual experiences vary.

After the procedure, redness along the vessel, small bruises, areas of firmness, or temporary darkening of the skin may occur. This does not always indicate a complication, but unusual or worsening symptoms should be discussed with a physician. It is not possible to promise completely uniform skin after a single session in advance: the vascular network and tissue response vary.

If spider veins are accompanied by heaviness, swelling, night cramps, or prominent veins, venous blood flow should be assessed. If necessary, vein duplex ultrasound is prescribed.

When CLaCS may be more useful

CLaCS is not a «stronger» procedure for everyone. Its advantage lies in combining two types of treatment for vessels that are difficult or impossible to puncture effectively.

The method may be appropriate in the following situations:

• the vessels are very thin, making needle insertion technically difficult;
• the vascular network is branched and superficial;
• some vessels are poorly suited to direct sclerosant injection;
• there is a tendency toward matting, meaning the appearance of a new fine network after the original vessels are closed;
• the spider veins have partially returned after sclerotherapy;
• it is necessary to treat not only the visible superficial branch but also the feeder vessel.

With CLaCS, the laser acts through the skin on fine vessels, while sclerotherapy is used for the feeder vein. Therefore, it is important to identify the source of blood flow correctly. If only the visible network is treated while significant reflux remains, the result may be incomplete or short-lived.

Sensations depend on the area and skin sensitivity. During the laser stage, brief tingling, warmth, or snapping sensations may occur. Cooling reduces discomfort. Redness, slight swelling, crusting, or temporary changes in skin color may occur after the procedure. Recovery and restrictions are discussed individually, taking skin phototype and the time of year into account.

CLaCS does not guarantee the absence of matting or the complete disappearance of all vessels. Its purpose is to provide a suitable tool for a particular type of vascular network.

CLaCS or sclerotherapy: how should you choose?

| Criterion | Sclerotherapy | CLaCS |

|---|---|---|

| Mechanism | A sclerosant is injected into the vessel with a needle | The laser acts through the skin, and the sclerosant is injected into the feeder vein |

| Suitable vessels | Vessels accessible for precise puncture | Very fine and complex superficial vessels and feeder branches |

| Sensations | Brief tingling or burning from the injection | Tingling and warmth during the laser stage, plus an injection during sclerotherapy |

| Number of procedures | Depends on the area, number of vessels, and tissue response | Depends on the vascular network and the selected combination of methods |

| Sun-related restrictions | Skin protection and compliance with the physician’s recommendations are necessary | Protecting the skin from the sun is especially important after laser treatment |

| When the method may be preferable | Easily accessible vessels and a clear local treatment goal | Very fine vessels, difficult access, matting, or recurrence after sclerotherapy |

The table shows general principles, not a ready-made treatment prescription. Spider veins that look identical may differ in depth, blood supply, and skin response.

Sometimes the optimal approach is to combine methods within one course of treatment. For example, some vessels can be treated with microsclerotherapy, while the finest superficial branches can be treated with laser as part of CLaCS. If a feeder vessel is present, it is addressed first or at the same time. The approach is determined by the anatomy of the vascular network, not by the name of the procedure.

Why vein duplex ultrasound is needed first

Before treating spider veins, it is important to determine whether there is a significant underlying blood-flow problem. Duplex ultrasound shows the direction of blood flow, the condition of the superficial and deep veins, the presence of reflux, and a possible connection between the spider veins and a larger vein.

This is especially important in the presence of the following symptoms:

• protruding or enlarged veins;
• one-sided swelling;
• persistent heaviness in the leg;
• pain along the course of a vein;
• recurrent appearance of vessels after procedures;
• skin changes in the lower-leg area.

When venous reflux associated with varicose veins is confirmed, treatment may not begin with the cosmetic network. Depending on the examination results, the physician discusses treatment for varicose veins, including EVLA, sclerotherapy, or another appropriate method. EVLA is intended for certain pathologically altered veins and does not replace CLaCS when treating fine spider veins.

Ultrasound helps distinguish cosmetic vessels from conditions requiring a different approach. Sudden one-sided swelling, rapidly increasing pain, marked redness and firmness along the course of a vein, shortness of breath, or chest pain are reasons to seek urgent in-person medical care. Such conditions cannot be assessed safely from a photograph or description.

What to consider before and after the procedure

During the consultation, I assess the color and size of the vessels, their location, depth, connections between branches, skin condition, and symptoms. You should tell the physician about medications, a tendency to bleed, allergic reactions, pregnancy, vascular diseases, and previous procedures. This helps determine the approach but does not guarantee an outcome without an in-person assessment.

After the procedure, it is usually important to:

• follow the recommendations for compression if it has been prescribed;
• avoid traumatizing the treated skin;
• protect the treated areas from the sun;
• not apply products to the skin that were not recommended by the physician;
• follow any prescribed restrictions regarding physical activity, saunas, and swimming pools;
• attend a follow-up visit if it is included in the treatment plan.

Sun-related restrictions are especially important after laser treatment: ultraviolet exposure may increase the risk of unwanted pigmentation. Specific time frames depend on the area, skin condition, and stage of treatment, so recommendations given to someone else should not be applied to you automatically.

I determine the treatment cost after the examination and ultrasound and provide a written estimate. You can schedule a consultation at M-Clinic in Tashkent by calling +998 99 883-93-21.

If the spider veins are accessible for precise puncture and there is no complex feeder reflux, sclerotherapy is often sufficient. If the vessels are very thin, difficult to puncture, associated with a tendency toward matting, or have recurred after sclerotherapy, CLaCS may be a more suitable option. In some cases, the methods are combined. Treatment should begin with an assessment of venous blood flow, not with choosing a procedure based on the vessels’ appearance.

This article is for informational purposes only and does not replace a consultation with a qualified physician. If you are experiencing symptoms, please see a specialist.