Duplex Ultrasound Evaluation of Lower Extremity Venous Insufficiency

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1 Review Article Duplex Ultrasound Evaluation of Lower Extremity Venous Insufficiency Robert J. Min, MD, Neil M. Khilnani, MD, and Piyush Golia Physicians unfamiliar with venous insufficiency, particularly disorders of the superficial venous system, often underestimate the complexity of the problem and the importance of proper evaluation before initiating treatment. In addition to a directed history evaluation and physical examination, additional evaluation with use of a variety of noninvasive diagnostic instruments, including duplex ultrasound, may be necessary when determining the cause, severity, and best treatment options available for a particular patient. After such evaluation, the treating physician should have a precise map of the patient s pathways of venous insufficiency, including sources of reflux (eg, saphenofemoral junction, saphenopopliteal junction, perforators), tributaries, vein size, and vein morphology. J Vasc Interv Radiol 2003; 14: DVT deep vein thrombosis, GSV great saphenous vein, SFJ saphenofemoraljunction, SPJ saphenopopliteal junction, SSV small sa- Abbreviations: phenous vein LOWER extremity venous insufficiency is one of the most common medical ailments, affecting at least 25% of women and 15% of men (1,2). Venous insufficiency is most commonly related to primary valvular incompetence and is less commonly a result of previous venous thrombosis. Effective treatment options exist for varicose veins but will be successful only if appropriately selected for a given patient. A focused history evaluation and physicalexamination can provide insight into the cause of venous insufficiency in many patients. However, when these evaluations are supplemented by careful duplex ultrasound (US) examination, the cause of the venous problem in a given patient can be reliably identified. In this review, the evaluation of lower extremity venous insufficiency with duplex US will be discussed, and support in From Cornell Vascular, Weill Medical College of Cornell University, 416 East 55th Street, New York, New York Received March 6, 2003; revision requested April28; finalrevision received June 2; accepted June 4. Address correspondence to R.J.M.; rjm2002@med.cornell.edu None of the authors have identified a potentialconflict of interest. SIR, 2003 DOI: /01.RVI the literature for its use in pre- and posttreatment evaluation will be presented. LOWER EXTREMITY VENOUS ANATOMY The veins of the lower extremity are conventionally divided into the deep and superficialvenous systems. These two venous systems are best thought of as components, along with the calf muscles, of a complex and efficient vascular reservoir and pump system. Superficial Venous System The superficialvenous system is composed of a complex web of subcutaneous collecting veins and thickerwalled conduit or truncal veins of the saphenous venous system. The collecting veins are thin-walled structures that are superficialto the saphenous fascia. They gather the blood from the skin and subcutaneous tissues, act as large-capacitance reservoirs, and passively drain into perforator or truncal superficialveins. The great (or greater or long) saphenous vein (GSV) and its tributaries represent the most important veins of the superficialvenous system. The GSV begins as the continuation of the dorsalvenous arch in the foot, travels anterior to the medial malleolus, and ascends the medialaspect of the leg, ultimately draining into the deep system at the saphenofemoraljunction (SFJ). It ascends the leg in the saphenous compartment, which is a subcutaneous space that is superficialto the muscular fascia and deep to the saphenous fascia in the leg and thigh (3 5). The saphenous fascia is a membranous layer of the subcutaneous tissue that is also known as the superficial or Scarpa fascia. The GSV generally has two major tributaries below and above the knee; it also receives blood from the externalpudendal, inferior epigastric, and external circumflex iliac veins just before it drains into the femoral vein (Fig 1). Classically, the GSV has been said to be duplicated in the thigh in as many as 20% of patients. However, recent examinations with use of the aforementioned definitions have demonstrated that true duplication, with two or three intrafascialveins in the saphenous compartment, occurs in less than 1% of cases. Large extrafascialtributary veins, which are termed accessory saphenous veins, can run parallel to the GSV and can functionally act as duplicated veins (6). The small (or short or lesser) saphenous vein (SSV) is the other principle truncalsuperficialvein. It begins on the lateral aspect of the foot, travels 1233

2 1234 Duplex US Evaluation of Lower Extremity Venous Insufficiency October 2003 JVIR Figure 1. Normalanatomy of the GSV and major tributaries. posterior to the lateral malleolus, and ascends the midline of the calf superficialto the muscular fascia and deep to the saphenous fascia. In approximately two thirds of patients, the SSV drains entirely into the popliteal vein just above the knee via the saphenopopliteal junction (SPJ). In as many as one third of patients, it drains into a posterior medialtributary of the GSV or directly into the GSV (as the Vein of Giacomini), or into a deep vein in the thigh via a perforator (7) (Fig 2). In many of these cases of variant drainage, a standard SPJ may also be present. The SSV is truly duplicated in 4% of cases; most often this is segmental, primarily involving the mid-portion of the vein (8). Figure 2. Anatomy of the SSV including common variant terminations and continuations. Deep Veins of the Lower Extremity The veins of the deep venous system are deep to the fascialinvestments of the muscles of the lower limb. These veins are more familiar to most physicians in the context of their importance to venous thromboembolic disease. They include the plantar vein of the foot, three pairs of tibialveins in the calf, and the popliteal and femoral veins in the thigh. In addition, numerous venous sinusoids found within the muscles of the lower limb are important components of this system. Those in the calf are most important and include the soleal and gastrocnemius veins. These sinusoids drain into other deep veins via valved connecting veins. All the deep veins are important elements of the pumping system and are responsible for returning blood from the muscles, as well as the blood collected from the superficial veins, back to the heart. Perforating Veins Perforating veins connect elements of the superficialvenous system with the deep venous system. These veins obliquely perforate the deep fascia and connect the collecting and saphenous veins with the tibial, femoral, popliteal, and sinusoidal veins. The larger perforators contain valves that direct flow from the superficial veins to the deep veins and are often found with a perforating artery. Four groups of clinically important perforating veins have been identified in fairly typicallocations and have been named Figure 3. Approximate points along the GSV (above the knee) and posterior arch vein (below the knee) where the superficial venous system connects with the deep venous system via important perforating veins. after important investigators in phlebology (Fig 3). PHYSIOLOGY OF THE NORMAL LOWER EXTREMITY VENOUS SYSTEM The veins of the lower extremity are not passive conduits but rather components of a complex vascular pumping mechanism responsible for actively returning blood to the heart against a substantialhydrodynamic gradient. This can be achieved only in the presence of competent valves, patent venous outflow tracts, and a functionalvenous pump. The failure of valves accounts for the majority of cases of venous insufficiency. In these cases, the pattern of clinical findings will depend on which valves fail.

3 Volume 14 Number 10 Minetal 1235 The propagation of blood from the lower leg back to the heart occurs against substantialhydrodynamic forces. In the erect position, the pressure created by the column of blood from the heart down to the ankle is approximately mm Hg. Propagation toward the heart depends on compression of the deep veins by calf muscles and functional one-way valves. The deep and superficial veins function as venous reservoirs that dilate substantially with minimal increases in intraluminal pressure. When the muscles in the leg, especially the calf, contract, the deep veins in the given compartment are externally compressed by extremely strong forces generated within their respective compartments. Competent valves cause the blood to flow only in one direction in the deep veins toward the heart. When the muscles relax, the compartment pressures decrease and blood flows into the deep veins from more caudaldeep vein segments. Blood also flows from superficial veins via perforators or at the SFJ or SPJ. The calf muscles function as a peripheral heart, with the valves in the saphenous veins, perforators, SFJ, SPJ, and deep veins analogous to the cardiac valves. PATHOPHYSIOLOGY OF VENOUS INSUFFICIENCY Venous insufficiency develops when a component of the venous system fails. With failure, the thin-walled superficial collecting veins are exposed to higher than normalpressures, causing dilation and elongation, resulting in varicosities, venulectasias, and telangiectasias. Valvular dysfunction, particularly in the superficial veins, is the most frequent cause of varicose veins in patients without skin changes or edema. Obstruction of the venous conduits and deep venous insufficiency are more frequent in patients with varicose veins associated with skin changes. Dysfunction of the calf pump is the least common cause of varicose veins (9). Valvular Insufficiency The pattern of venous reflux related to incompetent veins depends on which valves fail and through which pathway the leaking blood finds its way back to the deep venous system. Incompetence of the SFJ and GSV is a very common cause of significant varicose veins. Incompetence of the SPJ with SSV reflux is less common but can be clinically confused with abnormalities of the GSV. Perforator incompetence can also result in exposure of superficialveins to very high deep venous pressures, resulting in varicosities. Often, perforating vein incompetence is caused by overwhelming flow from a superficial venous leak. When the superficial vein is treated, the perforating vein is stressed by less shunt flow and can recover its competence. Reflux in the valves within tributaries of the GSV can also lead to varicose veins. Pudendalor glutealvarices are commonly seen in women during and after pregnancy. These can cause varicose veins by passing the high flow and pressure caused by the refluxing blood directly into collecting veins. Pudendalveins can also cause segmentalreflux in the GSV when their refluxing inflow overwhelms its valves. Anterior-lateral tributary and posterior-medialtributary reflux are other well-known causes of significant varicosities, which may or may not be associated with SFJ incompetence. Deep Venous Obstruction When the calf muscle pump functions normally, it generates sufficient pressure to move blood. However, if the outflow tract is obstructed, pressure elevations can result in dilation and secondary valvular incompetence. These forces may lead to perforator incompetence and subsequent venous hypertension and secondary superficialvenous insufficiency. Previous deep vein thrombosis (DVT) has been thought to be responsible for almost all cases involving venous ulceration. However, it has become clear that deep and superficialincompetence can result in the skin changes of advanced venous insufficiency (9). DIAGNOSTIC TESTS OTHER THANDUPLEX US A variety of indirect noninvasive tests have been developed over the years to identify the level of reflux and pattern of involvement. Photoplethysmography is a technique that quantifies the amount of blood in an extremity at rest and during the performance of certain maneuvers based on its reflectance of light. Air plethysmography can similarly measure volume displacement in a limb, which is mostly related to changes in venous volume, by placing a plastic cuff around a limb segment and measuring pressure changes during certain maneuvers. These techniques generate venous volume time curves with relatively characteristic patterns in patients with superficialor deep venous insufficiency or obstruction (10). Although still occasionally used, these diagnostic tests are unable to directly visualize the venous system and its variants and still leave the physician with many unanswered questions. Continuous-wave hand-held Doppler imaging became widely used in the early 1970s as a low cost technique to identify reflux in veins (11). With continuous-wave Doppler imaging, an experienced physician can construct a map defining the pattern of incompetence in most patients; however, it is still impossible to be sure which veins are being interrogated. Tributary incompetence, duplications, variant anatomy, and nearby deep veins are sometimes difficult to distinguish with certainty from the truncalveins being studied. This is particularly true behind the knee and at the groin. When compared with duplex US, the sensitivity and specificity rates in diagnosing incompetence of the GSV with continuous-wave Doppler imaging are 73% and 85%, respectively; 33% and 90%, respectively, for the SSV; and 48% and 90%, respectively, for the deep veins (12). Descending and ascending venography and varicography were used liberally until the late 1980s to supplement the previously mentioned noninvasive tests. Ascending venography was used to identify evidence of the obstructive sequelae of previous DVT and also helped in characterizing the location of perforator reflux. Descending venography was used to identify and define the extent and severity of deep venous insufficiency. Untilthe 1980s, these tests were considered to constitute the gold standard for such interpretations. However, these techniques are limited by their potential for complication, poor patient acceptance, difficulty in repeating the exam-

4 1236 Duplex US Evaluation of Lower Extremity Venous Insufficiency October 2003 JVIR Figure 5. Transverse duplex US image of an enlarged GSV found in its characteristic location within the saphenous sheath. Figure 4. Duplex examination of the right GSV with the US probe placed over the SFJ and manualcompression of the distalvein. ination, and the limited information that can be obtained about reflux in lower deep segments and superficial veins. DUPLEX US Duplex US examination of the superficialand deep venous systems has emerged as the most accurate and time-efficient toolto understand the causes of venous insufficiency, overcoming many of the shortcomings of the previously described techniques. The intuitive advantages of duplex US include its noninvasiveness, repeatability, reproducibility, and its combination of imaging of the veins with interrogation of their physiology. The goalof duplex US imaging in patients with venous insufficiency is to map out normaland abnormalvenous pathways and to identify the sources of incompetence and the levels of obstruction. Duplex US, more so than the other previously mentioned techniques, facilitates the identification of venous variants and the diagnosis of atypicalcauses of reflux. Severalstudies have demonstrated the effectiveness of duplex US in accurately mapping patterns of venous reflux (13 16). In addition to enabling visualization of abnormal venous pathways, duplex US provides reliable and objective follow-up. This ensures complete treatment of all involved venous segments, and not only detects but can often determine the cause of recurrences. Finally, duplex US can guide treatment in complex or difficult areas. However, there is still debate in the recent literature regarding the necessity of duplex US in every case (17 19). Most of the debate relates to the costs associated with the duplex US equipment and the time required for the patient and operators to complete the examination. However, these issues are becoming less important because the cost of quality diagnostic equipment has dramatically decreased in recent years. In addition, as endovascular techniques emerge as acceptable alternatives to traditional surgery, use of duplex US will increase. Possessing the equipment and necessary skills required to perform duplex US will become a prerequisite for all physicians involved in the care of patients with venous insufficiency (20). DUPLEX US EQUIPMENT REQUIREMENTS The latest-generation duplex US units have features and imaging tools that are more than sufficient for examination of the lower-extremity superficialvenous system. Minimum system requirements should include a display and a probe capable of gray-scale imaging at MHz and pulsed-wave Doppler imaging. Power Doppler imaging and the more expensive color Doppler imaging can facilitate the diagnostic examination but are not necessary to make an accurate diagnosis. A picture archiving system for documentation purposes is necessary and can include an economicalthermalpaper printer, conventionalfilm, or some sort of digitalarchivalsystem. PERFORMING THE EXAMINATION: TECHNOLOGIST OR PHYSICIAN? Most US technologists are sufficiently trained and skilled at performing quality examinations of the deep venous system of the lower extremi-

5 Volume 14 Number 10 Minetal 1237 Figure 6. Longitudinal view of the GSV at the SFJ examined with color Doppler imaging. ties. However, the vast majority are not experienced in thoroughly evaluating patients with varicose veins or other signs of superficialvenous insufficiency. Although training programs exist and very competent technologists are available, in our experience, the knowledge gained by performing the examination oneself outweighs the advantage of delegating this responsibility. No matter how elaborate the scanning protocol, many of the nuances of diagnosis and treatment selection are revealed only during carefulhands-on evaluation. In addition, showing patients the underlying cause of their varicose veins is invaluable when explaining the rationale behind a proposed therapy, and it strengthens the doctor patient relationship. With minimaladditionalinstruction, the majority of interventionalradiologists are capable of performing a complete examination for venous insufficiency. INDICATIONS FOR DUPLEX US Duplex US is indicated for evaluating patients with symptomatic or asymptomatic visible varicose veins who are contemplating therapy. This examination is also useful for patients without significant visible varicose veins who have symptoms suggestive of venous hypertension. Duplex US is necessary in evaluating patients with recurrent varicose veins after surgery (21,22). In most cases, duplex US is not useful for the evaluation of patients with spider telangiectasias or venulectasias. TECHNIQUE FOR EVALUATING SUPERFICIAL VENOUS INSUFFICIENCY Unlike evaluation for DVT, duplex US examination for superficialvenous insufficiency is performed in a standing position with the patient s weight supported on the contralateral limb. This position relaxes the muscles of the examined limb and ensures maximum venous distention, allowing simple maneuvers to be performed to identify refluxing venous segments. Great Saphenous Vein The affected leg is flexed and turned slightly outward with the patient s heelagainst the ground as seen in Figure 4. A platform or stool elevates the patient to eye level and can provide support for the patient during the examination. Evaluation should be performed in a systematic manner, most commonly beginning at the groin and proceeding peripherally. The entire length of the GSV from the SFJ to the lowest varicosities is examined in an axialprojection with grayscale technique. Figure 5 demonstrates the appearance of the GSV within the saphenous sheath of the proximal thigh, looking like Cleopatra s eye when seen on a cross section and found in its characteristic location between the saphenous and deep fascia (23). Vein diameter should be measured and the major tributaries should be followed and examined. The takeoff of varicose tributaries is noted, and these are followed down to any visible varicosities to confirm their etiology. The SFJ is then assessed for reflux in longitudinal and short-axis views. Color or power Doppler imaging can rapidly facilitate the identification of reflux by moving the probe along the vein while manually compressing and releasing lower venous segments (Fig 6). A Valsalva maneuver with use of standardized technique can identify reflux down to the first competent valve and may be useful when evaluating the SFJ (24). It has been shown that color Doppler imaging can underestimate the degree of reflux (25). Reflux is best identified, quantified, and documented with pulsed-wave doppler imaging immediately after an abrupt compression and release of a peripheral venous segment. Manualcompression of peripheralvein segments in the standing position with use of pulsed-wave Doppler imaging provides the greatest sensitivity and specificity in discriminating between normaland abnormal vein segments (25). Pneumatic compression does not offer any advantages. Centralvein compression or imaging in the supine position can provide misleading results (25). Compression maneuvers and duplex US imaging of the common femoralvein should be performed to assess for evidence of DVT or reflux. The course of the GSV and its major tributaries are followed with color or pulsed-wave evaluation, noting whether there is reflux and at what point it begins and ends; incompetent segments are traced directly to the varicosities. Perforating Veins Significant perforators associated with the GSV in the thigh and the

6 1238 Duplex US Evaluation of Lower Extremity Venous Insufficiency October 2003 JVIR Figure 7. Duplex US images of Hunterian perforator. (a) Transverse view of the enlarged perforator connecting the GSV with the deep venous system; (b) corresponding color Doppler interrogation demonstrating incompetence. Figure 8. Duplex US examination of the SSV with the US probe placed over the SPJ and the subject s knee slightly flexed to relax the popliteal fossa. posterior arch vein in the lower leg are sought and similarly examined. Transverse and oblique scanning planes are used when evaluating perforating veins to best image the long axis of these perforating vessels, as seen in Figure 7. Augmentation of blood flow Figure 9. Color Doppler and pulsed-wave Doppler examinations demonstrating GSV reflux on distal compression and release. by compression of the limb below the perforator is used to assess valvular integrity. Small Saphenous Vein The patient is then turned around and the SSV is examined. Again, the knee is slightly flexed and the muscles are relaxed to prevent venous compression by the muscles or popliteal artery (Fig 8). The SSV is identified and examined in cross section from the calf upward, and the location of the termination of the SSV is established. The SSV may drain well above

7 Volume 14 Number 10 Minetal 1239 Figure 10. (a) Transverse view of an enlarged GSV before treatment; (b) duplex US examination 1 week after endovenous laser ablation demonstrating vein wall thickening in an occluded GSV. the popliteal vein in as many as one third of limbs, but there may be an interconnecting vein in some cases. The size and competency of the SSV and its junctions and the relationship of the SSV to posterior calf varicosities are assessed, as was done with the GSV. This includes an examination for reflux in the vein of Giacomini. Perforating veins connecting the SSV with the venous sinusoids are noted, including the level of inflow and competence of the gastrocnemialveins. The popliteal vein is examined for reflux or evidence of previous DVT. In patients who have had surgicaltreatment for SSV incompetence, duplex US may revealvariant termination of the SSV above the popliteal fossa, with persistent reflux contributing to reconstitution of incompetent segments below. DUPLEX US IMAGING FINDINGS Figure 11. Duplex US examination of a markedly shrunken, fibrosed GSV 6 months after endovenous laser treatment. In the upright position, the GSV is generally 4 mm or smaller in diameter and the SSV is usually less than 3 mm in diameter. When insufficient, these veins are usually dilated, at times to enormous proportions, with incompetent GSVs reaching sizes of larger than 15 mm in diameter. As the gray-scale examination proceeds down the thigh, the caliber of the GSV may change depending on the outflow or inflow of incompetent segments. The diameter usually increases below a high-pressure leak such as at the SFJ or at an incompetent perforator, and will decrease after the takeoff of a refluxing tributary or a competent perforator draining into the deep system. As mentioned earlier, the regurgitant flow can usually be followed down to related varicosities, and this is often evident just by noting the caliber of the vessels. The reflux in the GSV may terminate after the takeoff of an enlarged and refluxing tributary. Alternatively, it may enlarge as it takes on refluxing inflow from sources such as an incompetent perforator or pudendalvein. Specific veins to examine include the anterior-lateral tributary and the posterior-medialtributary, which can reflux and have varicose tributaries with or without GSV reflux. In women who develop varicose veins during pregnancy, it is important to look for refluxing pudendal veins and to determine whether they contrib-

8 1240 Duplex US Evaluation of Lower Extremity Venous Insufficiency October 2003 JVIR ute to GSV reflux. In patients who have had SFJ ligation with or without stripping of the GSV, one should look for remnants of the GSV, duplicated veins, and enlarged, refluxing truncaltributaries, which can lead to recurrences. Normal valvular function allows a small amount of retrograde flow before complete closure. Some investigators rely on criteria for duration and velocity of reverse flow to define reflux. The most commonly used criteria is reverse flow lasting for more than 0.5 seconds (26). In our experience, use of this single criterion is limited in clinical practice, but it serves as a reasonable standard in research works. The presence of subtle reflux in excess of this criterion is rarely responsible for clinically important lower-extremity venous insufficiency. As it turns out, reflux for more than 0.5 seconds in the superficial veins almost always lasts more than 1 second, so this criterion has been successfully used (2,17). However, in the deep veins, reflux is frequently greater than 0.5 seconds but not greater than 1.0 seconds and its significance is controversial(2). In addition to the duration of reflux, its magnitude must be taken into account. Generally, significant reflux is obvious and characterized by retrograde flow evident after releasing compression placed on a venous segment below the region being examined. This can be demonstrated with use of color or pulsed-wave Doppler interrogation (Fig 9). Color for prograde flow and retrograde flow are arbitrary. This should be distinguished from a small blip of color immediately after release of the venous segment below, which is likely normal but should be confirmed with pulsedwave Doppler imaging. Similarly, some investigators define reflux in perforating veins as outward flow for more than 0.5 seconds (27). However, outward flow cannot by itself be taken as pathologic because outward flow is demonstrated in 21% of perforators in normallimbs (28). Perforating veins with diameters greater than 3.5 mm have been shown to be associated with reflux in at least 90% of cases (29). Much like the presence of reflux, size cannot be the sole determinant of clinically important perforators. These duplex US criteria must be used in combination with Figure 12. Common patterns of superficialvenous insufficiency: (a) SFJ incompetence with GSV reflux; (b) GSV reflux resulting from incompetent superficial external pudendal varices; (c) normal SFJ with incompetent Hunterian perforator leading to GSV reflux; (d) GSV reflux associated with an incompetent vein of Giacomini and SSV reflux. physical findings, particularly the clinicalpattern of venous insufficiency. Clinically significant perforators are usually those located centrally to incompetent venous pathways. It is important to understand that much of the blood refluxing down incompetent segments, such as an incompetent GSV, reenters the deep system through perforating veins. Those perforators peripheralto incompetent pathways may reflux only because they are overwhelmed by the addition of regurgitant flow to their normal workload. According to the standard reflux and size criteria described, these perforators will be classified as abnormal. However, many of these so-called abnormalperforators willregain their competence with treatment of the reflux in the incompetent GSV. In patients with varicose veins who have had previous treatment, a careful evaluation is essential in determining the etiology. Duplex US after high saphenous vein ligation will often reveal collateral reconstitution of the refluxing saphenous vein left behind at the original operation. Duplex US after ligation and stripping may revealextensive collateral formation or neovascularization from a saphenous stump, or tributaries filling incompetent vein segments or a functionally duplicated saphenous vein segment, as the underlying cause for recurrent varicosities. Normalappearance 1 2 weeks after endovenous laser ablation of the saphenous vein is that of a slightly smaller vein demonstrating wall thickening with absence of flow within the treated vein segment. The vein lumen is completely obliterated by the thickened wall, which has low-level echoes and is incompressible. Duplex US images of the GSV are shown before treatment (Fig 10a) and 1 week after endovenous laser treatment (Fig 10b). This thickening should be differentiated from acute saphenous vein thrombosis, in which the vein is also incompressible but the lumen is filled centrally with thrombus. After several weeks, resolution of the acute inflammation in the vein wall results in shrinking of the vein. After severalmonths, most of the treated vein segments fibrose and are difficult to identify. The typical appearance of a successfully treated GSV on color Doppler examination 6 months after endovenous laser ablation is seen in Figure 11. COMMONPATTERNS OF VARICOSE VEINS With use of duplex US, a map of incompetence can be constructed to

9 Volume 14 Number 10 Minetal 1241 understand the pathophysiology in a given patient. These maps should be constructed, used as the basis of a formalduplex US report, and kept as documentation of the venous examination. An example of maps produced for patients with some of the typical patterns of reflux is presented in Figure 12. CONCLUSION During the past decade, we have witnessed an increased understanding and interest in venous disorders, with advancement in noninvasive testing and development of new minimally invasive treatment options. Although these new techniques have had outstanding early and midterm results, more physicians are now attempting to treat the whole spectrum of venous disease. The most important factor in determining a good treatment outcome is making an accurate diagnosis. 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