Endovascular laser–tissue interactions and biological responses in relation to endovenous laser therapy

Lasers Med Sci. 2014 Mar;29(2):405-22. doi: 10.1007/s10103-013-1490-3.

Abstract

Endovenous laser treatment (ELT) has evolved into a frequently employed modality for the treatment of leg varicose veins. Due to the very high complete response rates, minimal complications and side effects, and the possibility to monitor therapeutic outcome noninvasively by duplex ultrasound, a considerable amount of reports have been published on clinical and translational studies, whereas disproportionally few studies have been performed to elucidate the molecular and cellular basis for post-ELT vessel obliteration. Consequently, this review addresses the putative molecular and cellular mechanisms responsible for varicose vein obliteration following laser irradiation in the context of endovenous laser–tissue interactions. First, the histological profile of laser-treated varicose veins is summarized, and an account is given of the temporal and spatial dynamics of cells involved in inflammation and remodeling in the heat-affected vein segment. Inasmuch as thrombotic occlusion of the venous lumen blocks circulatory access to the affected vessel segment and thermal damage in the vascular wall causes most cells to die, the majority of cells involved in inflammation and remodeling have to be recruited. Second, the (possible) biochemical triggers for the chemotactic attraction of immune cells and fibroblasts are identified, comprising (1) thermal coagula, (2) thrombi, (3) dead and dying cells in the vein wall, and (4) thermally denatured extracellular matrix proteins in the vein wall. The molecular biology underlying the chemotactic signaling and subsequent obliterative remodeling is elucidated. Finally, the relative contribution of every biochemical trigger to obliterative remodeling is addressed.

Publication types

  • Research Support, Non-U.S. Gov't
  • Review

MeSH terms

  • Chemotaxis
  • Cicatrix / physiopathology
  • Collagen / metabolism
  • Cytosol / metabolism
  • Endothelium, Vascular / metabolism
  • Endothelium, Vascular / pathology
  • Endovascular Procedures / methods*
  • Extracellular Matrix Proteins / metabolism
  • Fibroblasts / immunology
  • Fibroblasts / pathology
  • Humans
  • Inflammation / metabolism*
  • Laser Therapy / adverse effects
  • Laser Therapy / methods*
  • Phosphatidylserines / metabolism
  • Platelet Activation
  • Signal Transduction
  • Thrombosis / etiology
  • Varicose Veins / pathology*
  • Varicose Veins / surgery

Substances

  • Extracellular Matrix Proteins
  • Phosphatidylserines
  • Collagen