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Anatomy and Physiology of Veins; Principles of Sclerotherapy Gerant Rivera-Sanfeliz,MD. Venous Pathology. > 100 million people with venous disorders in US and Europe > 40% women and 20% men living with superficial venous disease > One million vein stripping procedures/year in US and europe.
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Anatomy and Physiology of Veins;Principles of SclerotherapyGerant Rivera-Sanfeliz,MD
Venous Pathology • > 100 million people with venous disorders in US and Europe • > 40% women and 20% men living with superficial venous disease • > One million vein stripping procedures/year in US and europe
Varicose Veins (Rutherford) • Venous Disorders - 211 of 2032 pages • Varicose Veins - 4 pages
Lower Extremity Veins • Deep system • Superficial system • Perforator system • Lateral subdermic venous system (LSVS)
Great Saphenous Vein (GSV)Previous Long Saphenous Vein (LSV) • Known as “el safin” by Arabic physicians, which means the concealed • Located along the medial aspect of the lower extremity • True duplication seen in 10-37%, often joining within 10 cm of the knee • Saphenous nerve • Saphenous compartment • Joins CFV at fossa ovalis (SFJ)
Small Saphenous Vein (SSV)Previous Lesser Saphenous Vein • Travels, with the sural nerve, along the lateral aspect of the leg • Joins popliteal vein at SPJ between the two heads of the gastrocnemius • May extend into the thigh and communicate with the femoral vein or GSV (Vein of Giacomini) • True duplication rarely reported
Perforating Veins • Communicate the deep and superficial systems • Horizontal or slightly upward orientation • Flow normally from superficial to deep • Common GSV perforators: - Hunterian (midthigh) - Dodd’s (above knee) - Boyd’s (below knee) - Cockett (distal leg)
Subcutaneous Veins • When abnormal: - Varicose (> 3mm) - Reticular (1- 3 mm) - Telangiectasia (spider)
Lateral Subdermic Venous System (LSVS) • Lateral aspect of leg above and below the knee • Embryonic superficial vessels fail to involute • Varicosities at young age, not increasing with age • Perforators
Three Anatomical Areas: Epifascial Subcutaneous veins Intrafascial Superficial veins Subfascial Deep veins Three fully interacting systems: superficial, deep, perforators
Vein Physiology • Pumps • Valves
Muscle Pump (Peripheral Heart) • Contractions propel blood toward heart • Relaxation draws blood from - superficial veins - lower deep veins
Thoracoabdominal Pump • Inspiration decreases intrathoracic pressure promoting venous return • Expiration reverses the process • Findings easily seen in US
Valves • Maintain unidirectional flow - Extremity to heart - Superficial to deep • GSV and SSV with terminal and preterminal valves • Terminal (sentinel or first) valve with firm thickened white cusps different from the rest of the valves
PathophysiologyVaricose Veins (VV) • Histologic studies show the collagen content of primary VV less than normal veins • Muscle content, although high, shows disorganization with areas broken up by similarly disorganized collagen • These findings may account for the decreased elasticity of VV
A. Normal B. Leaky Valve Syndrome -Valves become stretched -Allow back flow of Blood C. Superficial Valvular Reflux -Vein becomes engorged -Increasing pressure -Thinning walls -Weaken muscle support -Can enlarge vessel diameters greater than 10mm Pathophysiology> 90% LEVI Incompetent Valve Progression
Patterns of Reflux • Truncal or saphenous related reflux - GSV: 4/6 of VV - SSV: 1/6 of VV • Non-truncal reflux: 1/6 of VV - Pudendal, perforators - LSVS, Giacomini
SVI – SymptomsBad looks, bad feelings • Aching • Vague Discomfort • Heat/Burning • Skin changes, bleeding • ? Swelling All tend to increase with dependency and resolve with leg elevation or compression
SVI - Stigmata • Abnormal veins - telangiectasia (spider) - reticular - Non-saphenous VV (perforans varicosis) - Saphenous VV • Abnormal skin
SVI - Stigmata • Abnormal veins - telangiectasia (spider) - reticular - Non-saphenous VV - Saphenous VV • Abnormal skin
SVI - Stigmata • Abnormal veins - telangiectasia (spider) - reticular - Non-saphenous VV - Saphenous VV • Abnormal skin
SVI - Stigmata • Abnormal veins - telangiectasia (spider) - reticular - Non-saphenous VV - Saphenous VV • Abnormal skin
SVI - Stigmata • Abnormal veins - telangiectasia (spider) - reticular - Non-saphenous VV - Saphenous VV • Abnormal skin Courtesy of Dr. J. Golan
SVI - Stigmata • Abnormal veins • Abnormal skin - eczema - edema - corona phlebectatica - lipodermatosclerosis - ulceration
Classification Of CVDCEAP • C - clinical signs 0: No visible venous disease 1: Telangiectasias or reticular veins 2: Varicose veins 3: Edema 4: Skin changes 5: Healed ulceration 6: Active ulceration J Vasc Surg 1995; 21:635-645.
Imaging In PVI • Duplex ultrasonography • Has replaced plethysmography and venography • 7-10MHz linear array transducer • Examination performed in sitting and standing positions • Superficial and deep systems evaluated • Physiologic reflux: < 0.5 sec • Pathologic reflux: > 0.5 sec
Standard Surgical Treatment • Saphenous vein ligation • Saphenous vein stripping +/- ligation • Flush SFJ ligation, stripping the thigh portion of the GSV with excision of its tributaries and stab avulsion phlebectomies of the VV • SEPS (subfascial endoscopic perforator surgery)
Ligation vs. Stripping Recurence of VV higher with ligation when compared to stripping of the thigh portion of the GSV (McMullin GM, et al. Br J Surg 1991; 78:1139-1142/ Stonebridge PA, et al. Br J Surg 1995; 82:60-62/ Rutgers PH, et al. Am J Surg 1994; 168:311-315)
Fischer R, et al. The Unresolved Problem of Recurrent Saphenofemoral Reflux. J Am Coll Surg 2002; 195:80-94.
Surgical Complications • Wound Infection • Hematoma/severe bruising • Scarring • DVT • Recurrence Courtesy of Dr. J. Golan
One conclusion is apparent from the surgical literature: The crucial step in treating VV is removing the thigh portion of the refluxing saphenous vein from the circulation.
Percutaneous Options • Sclerotherapy • Endovenous Ablation - Radiofrequency - Laser
A small amount of damage will produce … … but a thrombosed vessel with intact endothelium will not sclerose
Volume Dilution • Zone 1: vessel is irreversibly injured • Zone 2: vessel will be able to recanalize • Zone 3:no endothelial injury, dilute sclerosant
Modern Sclerosants • Detergents • Hypertonic and ionic solutions • Cellular toxins
Detergents Detergent sclerosants work by a mechanism known as protein theft denaturation, in which an aggregation of detergent molecules forms a lipid bilayer in the form of a sheet, a cylinder or a micelle, which then disrupts the cell surface membrane and may steal away essential proteins from the cell membrane surface. Cell Death • Most commonly used • Sodium morrhuate, sotradecol, polidocanol, among others • Liquid or Foam
Advantages Injection is Painless Extravasation No Necrosis Disadvantages Pigmentation Intermediate Polidocanol (0.5%)
Sclerotherapy - Results • Excellent for small veins: reticular, telangiectasias • High recanalization rates for larger veins • GSV: > 50% recurrent reflux by US, which is likely the prelude for recurrence of VV
Sclerotherapy-Complications • Pigmentation • Matting • Ulceration Courtesy of Dr. J. Golan
Sclerotherapy vs. Surgery • Prospective 10 year study (121 96) • VV and superficial incompetence • Group A: Sclerotherapy (39) • Group B: Ligation + Sclerotherapy (40) • Group C: Ligation only (42) • No incompetence at SFJ in surgical groups • Sclerotherapy with 20-44% reflux • Sclerotherapy cheaper, surgery superior Belcaro G, et al. Angiology 2000; 51:529-534.
Sclerosing Foam • Orbach(1944): the air block technique • Displaces blood • Induces more spasm • Tiny bubbles covered by tensio-active liquid • Treat larger veins
1ml of 3% STS injected in a vein dilutes with 10ml of blood Final drug concentration: 0.3% 1ml of 1% Foam STS injected in the same vein displaces blood Final drug concentration: 1%
Sclerosing Foam • Less volume • More potent • Morbidity appears similar to liquid sclerosants • Being used clinically since 1997, results in GSV better than liquid ~ 20-30% recanalization
Percutaneous Options • Sclerotherapy • Endovenous Ablation - Radiofrequency - Laser