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940-nm laser for treatment of saphenous insufficiency: histological analysis and long-term follow-up.

OBJECTIVE
Currently, many methods are available for the treatment of saphenous insufficiency. Modalities available include surgery, sclerotherapy, and radiofrequency closure. Recently, a method has been introduced using laser energy for the treatment of the saphenous vein using a bare-tipped fiber. Our experience using the 940-nm wavelength forms the basis of this report.


METHODS
Indications for treatment with laser obliteration alone was saphenous insufficiency, a saphenofemoral junction of less than 15 mm in diameter and absence of concurrent anticoagulation therapy. Ninety-two percent of the patients were in Class C-2 to C-4, and 8% were in C-5 to C-6. Eight percent had a concurrent high ligation of the saphenous vein. Fifteen patients were treated at varying energy levels and time durations for saphenous insufficiency using a bare-tipped fiber and the 940-nm wavelength laser (SkinPulse S by Dornier). These patients then had histologic evaluation of the treated vein. An additional 620 patients were subsequently treated for saphenous insufficiency using the 940- nm wavelength laser.


RESULTS
At 1-sec pulse durations, histologic studies reveal endothelium and subendothelial damage as the initial response to laser damage. At 3 months, endothelium was still absent, with organized thrombus in the lumen. At 6 months, at 1-sec pulse duration, thrombus organization was still present with evidence of muscle wall damage. Ultrasound evaluation revealed gradual diminution in saphenous vein diameter over 6 months, with absence of reflux and normal flow at the saphenofemoral junction in 95% of patients. For pulse durations of greater than 1 sec, there was transmural injury.


CONCLUSION
Laser treatment of the saphenous vein was associated with no complications in our series of patients. The vein remained closed in 95% of those treated. This technique may replace other treatment modalities in up to 90% of patients.