Endovascular Laser Treatment of Varicose Veins

Since 2001, endovenous laser ablation procedures have been reported to be safe and effective methods of eliminating the proximal portion of the greater saphenous vein (GSV), the small saphenous vein (SSV), and even tributary and perforator veins from the venous circulation, with faster recovery and better cosmetic results than traditional surgical ligations and stripping. Lasers of varying wavelengths deliver light energy to the vein through an indwelling fiber, which results in direct or indirect damage to the vein wall intended to result in sclerosis and ultimately resorption of the vein. As with traditional surgical treatment of incompetent saphenous veins, when following these endovenous laser ablation procedures it is necessary to treat any remaining incompetent portion of the GSV or SSV, persistent incompetent perforator veins, and varicose tributaries, typically with sclerotherapy and/or phlebectomy.

The first generation of endovenous lasers used wavelengths (800–1000 nm) that targeted hemoglobin as the chromophore. Newer, longer-wavelength lasers (1300–1600 nm) target water and thus the endothelial cell wall. Original reports of endovenous laser ablation described the use of pulsed laser energy. Because of patient reports of painful bruising secondary to vein wall perforations with the pulsed mode, the technique was altered to continuously applied delivery.

Lasers of higher wavelength targeting water in the vein wall with lower power settings has seemed to significantly lessen discomfort by causing fewer perforations and perivenous bleeding, the presumed cause of the pain. Reports of randomized comparative clinical trials have established better patient outcomes with higher-wavelength lasers than lower-wavelength lasers. Just as laser generators have evolved, the original 600-μm bare-tipped fibers have evolved to covered and radial fibers and centering devices, all designed to limit the risk of vein wall perforation and to more evenly distribute endothelial thermal injury.

Patient Selection

Clinical indications for laser therapy have been established ( Box 1 ). Absolute contraindications for this form of venoablation include restricted patient mobility, acute deep or superficial vein thrombosis, significantly impaired deep venous outflow, and any active infectious process. Relative contraindications, including arteriovenous malformations, hypercoagulable states, sclerotic or tortuous veins, and large or aneurysmal veins can be safely ignored as one gains experience with the laser ablation technique.

BOX 1

Clinical Indications for Laser Ablation

Superficial venous insufficiency
Duplex scan with reflux >0.5 sec
Patent deep system
Vein conducive to cannulation
Adequate patient mobility

Strong consideration of thrombophilia should be given preoperatively to patients with a history of deep vein thrombosis (DVT), recurrent episodes of acute superficial thrombophlebitis, multiple spontaneous abortions, or strong family history of DVT or clotting disorders. The physician should be aware of the American College of Chest Physicians guidelines for risk assessment for DVT, because they may be helpful in choosing which patients should receive prophylactic anticoagulation before undergoing endovenous laser ablation. Although the risk of DVT following these procedures is low (<1%), such a potentially life-threatening outcome following treatment of relatively benign disease could be catastrophic.

Duplex ultrasound (US) is integral to an accurate diagnosis for appropriate patient selection. However, several factors have resulted in the frustration of inconsistent duplex reports. Duplex examination is operator dependent, and training in superficial venous disorders has only very recently improved somewhat. The complexity of venous hemodynamics has not been previously well understood or appreciated. Finally, there is considerable inconsistency in the sensitivity of duplex equipment, which hampers identification of lower level reflux in some symptomatic patients, leading to inadequate diagnosis and treatment. In an attempt to explain one of the causes of inconsistent duplex reports, the author a study was conducted by a colleague to gauge the effect of the sensitivity of different US machines. One can see that in comparing the most sensitive equipment (“D”) with the least sensitive equipment (“E”), agreement was present only two thirds of the time. It is therefore apparent that reflux can be missed in more than one third of patients if the least sensitive equipment is used.

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