title: Lymphatic transport in patients with chronic venous insufficiency and venous leg ulcers following sequential pneumatic compression.
abstract: BACKGROUND
  Recent advancements in near-infrared fluorescence lymphatic imaging (NIRFLI) technology provide opportunities for non-invasive, real-time assessment of lymphatic contribution in the etiology and treatment of ulcers. The objective of this study was to assess lymphatics in subjects with venous leg ulcers using NIRFLI and to assess lymphatic impact of a single session of sequential pneumatic compression (SPC).
  
  
  METHODS
  Following intradermal microdoses of indocyanine green (ICG) as a lymphatic contrast agent, NIRFLI was used in a pilot study to image the lymphatics of 12 subjects with active venous leg ulcers (Clinical, Etiologic, Anatomic, and Pathophysiologic [CEAP] C6). The lymphatics were imaged before and after a single session of SPC to assess impact on lymphatic function.
  
  
  RESULTS
  Baseline imaging showed impaired lymphatic function and bilateral dermal backflow in all subjects with chronic venous insufficiency, even those without ulcer formation in the contralateral limb (C0 and C4 disease). SPC therapy caused proximal movement of ICG away from the active wound in 9 of 12 subjects, as indicated by newly recruited functional lymphatic vessels, emptying of distal lymphatic vessels, or proximal movement of extravascular fluid. Subjects with the longest duration of active ulcers had few visible lymphatic vessels, and proximal movement of ICG was not detected after SPC therapy.
  
  
  CONCLUSIONS
  This study provides visible confirmation of lymphatic dysfunction at an early stage in the etiology of venous ulcer formation and demonstrates the potential therapeutic mechanism of SPC therapy in removing excess fluid. The ability of SPC therapy to restore fluid balance through proximal movement of lymph and interstitial fluid may explain its value in hastening venous ulcer healing. Anatomical differences between the lymphatics of longstanding and more recent venous ulcers may have important therapeutic implications.
authors.affiliation: Brown Foundation Institute of Molecular Medicine, The University of Texas Health Science Center at Houston, Houston, Tex.
authors.forename: John C
authors.initials: JC
authors.lastname: Rasmussen
authors.affiliation: Brown Foundation Institute of Molecular Medicine, The University of Texas Health Science Center at Houston, Houston, Tex.
authors.forename: Melissa B
authors.initials: MB
authors.lastname: Aldrich
authors.affiliation: Brown Foundation Institute of Molecular Medicine, The University of Texas Health Science Center at Houston, Houston, Tex.
authors.forename: I-Chih
authors.initials: IC
authors.lastname: Tan
authors.affiliation: Brown Foundation Institute of Molecular Medicine, The University of Texas Health Science Center at Houston, Houston, Tex.
authors.forename: Chinmay
authors.initials: C
authors.lastname: Darne
authors.affiliation: Brown Foundation Institute of Molecular Medicine, The University of Texas Health Science Center at Houston, Houston, Tex.
authors.forename: Banghe
authors.initials: B
authors.lastname: Zhu
authors.affiliation: Division of Vascular Surgery, Tufts Medical Center, Boston, Mass.
authors.forename: Thomas F
authors.initials: TF
authors.lastname: O'Donnell
authors.affiliation: Wound Care Clinic, CHI St. Luke's Health - The Woodlands Hospital, The Woodlands, Tex.
authors.forename: Caroline E
authors.initials: CE
authors.lastname: Fife
authors.affiliation: Brown Foundation Institute of Molecular Medicine, The University of Texas Health Science Center at Houston, Houston, Tex. Electronic address: eva.sevick@uth.tmc.edu.
authors.forename: Eva M
authors.initials: EM
authors.lastname: Sevick-Muraca
mesh_terms: D000368:Aged; D005260:Female; D006801:Humans; D048228:Intermittent Pneumatic Compression Devices; D042601:Lymphatic Vessels / Q000503:physiopathology*; D008297:Male; D008875:Middle Aged; D010865:Pilot Projects; D014647:Varicose Ulcer; D014689:Venous Insufficiency / Q000628:therapy*; D014945:Wound Healing