Varicose veins form when the one-way valves in leg veins fail, so blood flows backward and pools. A faulty vein can often be closed from the inside through a needle puncture, rather than removed through surgical incisions.
Calf pain or swelling that gets worse, chest pain or trouble breathing after a vein procedure can be signs of a blood clot. Cleveland Clinic advises going to the emergency room for these and other warning signs, such as coughing up blood, a fast heartbeat or fainting. For chest pain or trouble breathing, call 911.
In the video above, vein specialist Dr. Peter Morgan explains how ClariVein closes a faulty vein without heat, how it differs from laser and radiofrequency ablation, and what happens when venous insufficiency goes untreated.
Why treat a faulty vein
The Society for Vascular Surgery (SVS) says varicose veins can worsen without treatment, causing aching, swelling, skin changes, blood clots or sores. Dr. Morgan says uncorrected venous insufficiency gets worse at a pace that varies, depending partly on heredity and partly on a person’s work. He lists pain, swelling, restless legs and enlarged veins as typical signs.
In another video, Treatment of Varicose Veins, he explains that a vein flowing backward only hurts circulation out of the leg, so treatment closes it.
Ultrasound mapping comes first
The SVS says a duplex ultrasound, which measures blood flow in the leg veins, pinpoints the problem veins and helps decide how to treat them.
Catheter treatments mainly target long, fairly straight veins near the surface, such as the great saphenous vein, which runs from the groin to the ankle, explains RadiologyInfo.org, from the American College of Radiology and the Radiological Society of North America. They’re used more often to ease symptoms than for appearance.
On insurance, the SVS notes that most insurers require at least three months of compression stockings before they cover other varicose vein treatments.
Heat-based ablation: radiofrequency and laser
Guided by ultrasound, the doctor threads a thin catheter into the vein through a small opening. A radiofrequency electrode or laser fiber heats the vein as the catheter is pulled back, sealing it, and the vein fades over time, MedlinePlus and RadiologyInfo explain. Numbing fluid is first injected around the vein to shield nearby tissue from the heat; RadiologyInfo calls these injections the most uncomfortable part. Cleveland Clinic says the procedure usually takes about an hour, and you go home the same day.
Dr. Morgan explains that this numbing solution takes several needle sticks up the leg and can leave the leg feeling full or tight, with some fluid leaking out.
Options that don’t use heat
These close the vein without heat or numbing fluid along the vein. The American Vein & Lymphatic Society (AVLS) says heat and non-heat methods are both recommended for these veins, depending on the doctor’s expertise and the patient’s preference.
- Mechanochemical ablation (ClariVein). A thin wire spins inside the vein to damage its lining while a liquid sclerosant, a medicine that scars the vein shut, is infused. Dr. Morgan compares the wire to “a skip rope” and notes that heat always carries some risk to a nearby nerve or muscle. A 2024 AVLS position statement says ClariVein causes less discomfort during the procedure and can be used below the knee, where heat poses more risk to nerves. But treated veins reopen more often than after heat: in one trial, about half were still closed at five years, compared with about 9 in 10 after laser. AVLS calls it an option when heat ablation isn’t suitable.
- Medical adhesive (glue). A catheter places small amounts of medical glue (cyanoacrylate) to seal the vein; the VenaSeal system was approved in the U.S. in 2015. In one trial, 91% of glued veins and 85% of veins treated with radiofrequency were still closed at five years, AVLS reports. Compression stockings aren’t needed for the vein to close. Trade-offs: the glue stays in the body, inflammation along the vein is more common than after heat, and about 6% of patients get an allergic-type rash, usually mild. AVLS says it isn’t suitable for people with certain autoimmune or inflammatory conditions.
- Foam sclerotherapy. A foam sclerosant is injected under ultrasound guidance to close larger veins, according to RadiologyInfo and the SVS. A ready-made foam (polidocanol) is FDA-approved for the great saphenous vein and its branches. Cleveland Clinic says you may need more than one session.
Recovery and compression
Cleveland Clinic, RadiologyInfo, the SVS and MedlinePlus describe what to expect after ablation:
- a bandage over the small opening, with no stitches
- a compression stocking or bandage; MedlinePlus describes wearing stockings during the day for about a week
- walking often, and not spending too much time in bed
- no flying for two weeks, and no strenuous exercise until your provider clears you
- a return to work within a few days for most people
- a follow-up ultrasound, often about a week later, to confirm the vein is sealed
- soreness, tingling or bruising that usually improves within a few weeks
Risks
MedlinePlus says these treatments are generally safe. Risks include blood clots, nerve damage, a vein that doesn’t close or reopens, irritation, bruising and scarring. RadiologyInfo adds that painful, red swelling of the treated vein is not uncommon, heat damage to nerves is rare and usually short-lived, and a clot traveling to the lungs is extremely rare. Dr. Morgan says all of these procedures are very safe, with few complications.
Results and the chance of needing more treatment
RadiologyInfo says heat ablation closes the target vein almost 100% of the time, but small branch veins near the skin often need sclerotherapy or phlebectomy (removal through tiny cuts), sometimes in the same session. Varicose veins can return even after effective treatment, Cleveland Clinic notes, more often with obesity, long daily sitting or a later pregnancy. Dr. Morgan says that if it recurs, it can be treated without a major procedure.
How this compares with vein stripping
In vein stripping, the surgeon removes the vein through incisions in the groin and below the knee, usually under general anesthesia. Most patients return to normal activities after about four weeks, the SVS says. RadiologyInfo says ablation is more effective than stripping, with fewer complications and much less pain during recovery.
Questions to ask your doctor
- What did my ultrasound show, and which veins are flowing backward?
- Should I try compression stockings first, and does my insurance require it?
- Which closure methods suit my veins, and how do they compare for discomfort, recovery and the chance the vein reopens?
- How long will I wear compression, and when can I fly, exercise and return to work?
- Which symptoms after the procedure mean I should call you or go to the emergency room?
Dr. Morgan is a vein specialist in the Houston area. See Dr. Morgan’s Best Docs Network profile for more about the practice.
Sources
- Society for Vascular Surgery. Varicose Veins.
- RadiologyInfo.org (American College of Radiology and Radiological Society of North America). Varicose Vein Treatment (Endovenous Ablation of Varicose Veins).
- RadiologyInfo.org (American College of Radiology and Radiological Society of North America). Varicose Veins.
- Cleveland Clinic. Endovenous Thermal Ablation.
- Cleveland Clinic. Varicose Veins.
- Cleveland Clinic. Sclerotherapy.
- MedlinePlus (U.S. National Library of Medicine). Varicose vein - noninvasive treatment.
- American Vein & Lymphatic Society. Mechanochemical Chemically Assisted Ablation of Varicose Veins for Venous Insufficiency: Position Statement (2024).
- American Vein & Lymphatic Society. Cyanoacrylate Endovenous Ablation: Position Statement (2024).
- U.S. Food and Drug Administration. Varithena (polidocanol injectable foam) prescribing information.
This article is for general information only and is not medical advice. Talk with a qualified health professional about your own situation. If you think you may have a medical emergency, call 911.
