Duplex Ultrasound Evaluation of Patients With Chronic Venous Disease of the Lower Extremities

Vascular and Interventional Radiology Review Khilnani Chronic Venous Disease of the Lower Extremities Vascular and Interventional Radiology Review Neil M. Khilnani 1 Khilnani NM Keywords: chronic venous disease, duplex ultrasound, endovenous thermal ablation, saphenous reflux, superficial venous insufficiency DOI:10.2214/AJR.13.11465 Received July 1, 2013; accepted without revision July 27, 2013. 1 Department of Radiology, Weill Medical College of Cornell University and The New York Presbyterian Hospital-Weill Cornell Medical Center, Weill Cornell Vascular, 2315 Broadway, 4th Fl, New York, NY 10024. Address correspondence to N. M. Khilnani (nmkhilna@med.cornell.edu). This article is available for credit. AJR 2014; 202:633 642 0361 803X/14/2023 633 American Roentgen Ray Society Duplex Ultrasound Evaluation of Patients With Chronic Venous Disease of the Lower Extremities OBJECTIVE. This article will describe the elements of performing a thorough venous ultrasound evaluation of the lower extremity in patients with manifestations of chronic venous disorder. The emphasis will be on the evaluation of superficial venous reflux. Only the specific aspects of the evaluation of the deep system pertaining to chronic venous disease will be discussed. CONCLUSION. Duplex ultrasound requires the examiner to solve a puzzle to explain the patient s clinical manifestations. Patients who have been treated with surgery, thermal ablation, or ultrasound-guided sclerotherapy will require duplex ultrasound after treatment to identify complications, gauge the extent of treatment success, and evaluate the cause for any recurrence. C hronic venous diseases, including varicose veins, are among the most common medical conditions. Chronic venous diseases are never cured, and patients with these disorders will occasionally require repeat evaluation and treatment. Because the incidence of these conditions increases with age, the number of patients who will seek medical attention and require imaging will increase. Chronic venous diseases are the result of lower extremity venous hypertension. Venous hypertension is usually caused by reflux in the superficial venous compartment. Less commonly, it is the result of deep venous compression, postthrombotic stenosis or occlusion, and deep venous reflux. Rarely, venous hypertension is caused by vascular malformations, arteriovenous fistula, and neuromuscular disorders. The overwhelming majority of lower extremity venous diagnostic ultrasound studies are performed to evaluate a patient for a possible acute deep venous thrombosis. The expertise to perform these types of studies is ubiquitous; however, the knowledge and skills required to perform an examination to evaluate patients with chronic venous disease is less widely available. This article will describe the elements of performing a thorough venous ultrasound evaluation of a lower limb in a patient with manifestations of chronic venous disorder. National Standards Standards for the performance of lower extremity venous duplex ultrasound for the evaluation of chronic venous disease have been published [1 4]. The American College of Radiology (ACR) and the Intersocietal Accreditation Commission are the two most widely recognized accrediting organizations for venous ultrasound. Each has used the consensus of experts to develop protocols, policies, and procedures that establish benchmarks for effective practice and for quality control [5, 6]. The process to obtain accreditation from these organizations enables physician practices to show the quality of their examinations and their commitment to quality patient care. We recommend that readers review these documents and consider the value of accreditation for their own practices. Increasingly, reimbursement is being tied to proof of quality, and these two methods of accreditation have been widely recognized by the insurance industry for showing quality. Indications for Lower Extremity Duplex Ultrasound All patients being considered for treatment of varicose veins or venous ulceration (clinical, etiologic, anatomic, pathophysiologic [CEAP] clinical stage, C2 C6) [7] should undergo ultrasound of the venous system to determine the location and patterns of superficial and deep venous incompetence and of AJR:202, March 2014 633

Khilnani any deep venous obstruction. Patients with an unclear source of venous edema or leg pain consistent with venous hypertension should also undergo venous ultrasound. Patients seeking treatment of spider veins (CEAP clinical stage, C1) in nonsaphenous distributions, such as on the lateral thigh area, do not require duplex ultrasound evaluation. However, if the spider veins are found in the distribution of the great saphenous vein (GSV), duplex ultrasound can identify those patients who might require treatment of GSV reflux to achieve durable and successful results with treatment. Superficial Venous Anatomy and Nomenclature The superficial venous anatomy is quite predicable, with certain parts more or less developed in a given patient. It is composed of the saphenous trunks and their tributaries and innumerable subcutaneous collecting veins. The most recognized components are the GSV and small saphenous vein. The use of the terms long, greater, short, and lesser have also been discouraged by international consensus to avoid the confusion often caused by the use of abbreviations [8, 9]. In addition, the consensus statement has attempted to standardize the names of the major tributaries of the saphenous veins as used in this article. The deep veins are found deep in relation to the fascial investiture of the muscular compartment. The superficial veins are outside of the muscular fascia. In the vicinity of the saphenous veins and some of their tributaries, the fascia splits into superficial and muscular fascia. The saphenous veins are deep in relation to the superficial fascia but superficial to the muscular fascia and are found in the saphenous compartment and are considered intrafascial. The GSV begins on the dorsum of the foot and ascends the medial calf and thigh to join the common femoral vein near the groin crease (Fig. 1). Three small tributaries typically drain into the GSV reflux near the saphenofemoral junction that are important in that they are often a source of recurrent varicose veins after surgical ligation along with removal of the GSV (high ligation and stripping). Veins parallel to the GSV are named on the basis of their position relative to the fascia [8 10]. A vein that runs parallel to the GSV but in the saphenous space in the anterior or medial thigh should be referred to as the anterior or posterior accessory GSV. The anterior accessory GSV is the more common parallel channel to the GSV and reflux in it is frequently responsible for anterior thigh varicose veins. The anterior accessory GSV most typically originates from the GSV just below the saphenofemoral junction and runs in the saphenous space anterior to the superficial femoral artery and the femoral vein. It may turn medially to join the GSV in the lower thigh or, occasionally, functionally exist as the GSV when the true GSV is segmentally hypoplastic or aplastic in the upper and midthigh. Another commonly found vein that runs parallel to the course of the GSV but is outside the fascia is known as the superficial accessory saphenous vein. This common extrafascial vein is often segmentally present in the mid to lower thigh and the upper to midcalf and often serves as the primary flow channel when the true GSV is either hypoplastic or aplastic in these areas. It is often misinterpreted as a GSV close to the skin when, in fact, it is outside the saphenous compartment. Of note, it has been observed that the saphenous compartment is often poorly developed at and just below the knee, and accurate classification of the position of a vein relative to the fascia is occasionally impossible in this location. The small saphenous vein begins on the lateral aspect of the foot, passes posterior to the lateral malleolus, and ascends the midline of the calf in a similar intrafascial space as the GSV (Fig. 2). The cephalad termination of the small saphenous vein is variable. The classically described anatomy is for the small saphenous vein to terminate into the popliteal vein at the saphenopopliteal junction just above the level at which the two heads of the gastrocnemius muscles diverge. This can be found to be the dominant drainage in up to two thirds of all limbs. However, the small saphenous vein usually also has a connection with a vein on the posterior thigh and in about one third of the time represents the dominant path for flow. The cephalad (or thigh) extension travels in an intrafascial space similar to the saphenous veins. The thigh terminations of this vein are variable and include termination in a more lengthy extension that communicates with a tributary of the GSV (the cephalad extension in this case is commonly known as the Giacomini vein, or the intersaphenous vein in the new nomenclature) into a perforating vein in the posterior thigh and into the gluteal vein (which passes under the gluteal fold to later drain into the internal iliac vein) in descending order of frequency (Fig. 2). Combinations of the described small saphenous vein termination patterns are common in many patients, with one pattern the dominant form of drainage or abnormality in each case. Innumerable perforating veins direct blood from the superficial to the deep veins in the lower extremity. These veins pass through the muscular fascia and have valves that direct blood from the superficial to the deep compartment. A new nomenclature to describe perforating veins has been advocated on the basis of their location; however, the traditional terms using the names of physicians who were responsible for understanding their significance is found in older literature and, as a result, is worth reviewing [8, 9]. Clinically important connections include the medial thigh perforating vein between the GSV and the femoral vein in the mid and low medial thigh (previously known as the Dodd and Hunter perforators ), the lateral thigh perforator, the popliteal fossa perforating vein, and the paratibial perforating veins connecting the GSV and the upper posterior tibial veins (previously known as the Boyd perforating veins ). The perforating veins that have been classically associated with advanced forms of venous disorders, including venous ulceration, are the posterior tibial perforating veins connecting the posterior circumflex vein of the calf and its branches and the posterior tibial veins (previously known as the Cockett perforators ). Superficial Veins of the Lower Extremity: Duplex Ultrasound Anatomy The GSV and small saphenous vein, found within the saphenous compartment, have characteristic ultrasound appearances. During axial or (transverse) imaging, both of these veins will have the appearance of Cleopatra s eye or of the Seattle Seahawks helmet logo (Fig. 3). The anterior accessory GSV, which courses anterior to the GSV, almost always drains into the GSV just inferior in relation to the saphenofemoral junction. It can be seen on axial images just below the saphenofemoral junction anterior to the femoral vein and superficial femoral artery in its own more anterior saphenous compartment (Fig. 4). Most tributaries of the GSV and small saphenous vein are unnamed and are found within the subcutaneous fat and traverse the superficial fascia before joining one of the saphenous trunks (Fig. 5A). Peripheral (caudal) to the takeoff, a large incompetent tributary vein, the GSV, or small 634 AJR:202, March 2014

Chronic Venous Disease of the Lower Extremities saphenous vein may dramatically decrease in caliber or may not be visible on duplex ultrasound (Fig. 5B). Duplex Ultrasound Examination Technique Duplex ultrasound examinations of patients with chronic venous disease are performed to identify the cause of the venous hypertension. In many patients, there may be several coexistent refluxing pathways and, less commonly, coexistent obstructions. Identifying all of them is the endpoint. When evaluating patients for deep and superficial reflux, the examination should ideally be performed with the patient standing or in a relatively steep reverse Trendelenburg position. The patient can be positioned on a step stand to elevate the legs, which facilitates the performance of the examination. The examination table should be elevated behind a standing patient so the patient can lean against it for balance. The patient is asked to turn the leg under examination outward for scanning of the inner thigh and calf (Fig. 6A). Generally, the superficial venous examination begins with the GSV at the saphenofemoral junction. The proximal axial diameters of the GSV and the anterior accessory GSV are measured. Each vein is followed from the saphenofemoral junction to the ankle (GSV) or to its thigh termination (anterior accessory GSV). The caliber of the GSV and anterior accessory GSV are continuously assessed because changes in caliber can provide important clues to physiologic disturbance. Peripheral to the connection to incompetent tributary veins, the caliber of the saphenous vein often decreases (Fig. 5B). Conversely, the caliber of the saphenous vein will generally increase at the level of inflow of reflux from a significant incompetent perforator vein or incompetent tributary. Although a competent vein has a small diameter and a refluxing vein a larger diameter, the reliability of size in discriminating between competent and incompetent saphenous veins is not sufficiently accurate. The competence of each vein and the saphenofemoral junction are assessed with Doppler ultrasound after augmenting flow through the examined segment by compressing the calf and then observing for retrograde flow with release of the calf pressure. This can be done with rapidly filling and releasing pneumatic cuffs. However, manual compression and release have been found to be as reliable [11]. Although competence is classically assessed in the longitudinal projection, a steeply upward-angled transverse view with color Doppler ultrasound is much easier and more efficient and accurately identifies reflux (Fig. 6). Each vein is evaluated with color Doppler ultrasound every few centimeters to identify reflux. In evaluating the anterior accessory GSV, compression of the lower thigh may also be useful. Any vein segment with color-documented reflux or those suspected of having reflux by vein dilation or by a relationship to varicose veins is evaluated with pulsed-wave Doppler imaging to quantify the duration of retrograde flow. On release of compression, little if any reflux should be noted in normal veins. Retrograde flow after release of calf compression lasting longer than 0.5 second is considered abnormal [12]. However, in most patients with clinically significant reflux, the retrograde flow after release of the calf compression often lasts for several seconds (Fig. 7). GSV reflux is caused by saphenofemoral junction incompetence in many patients. However, nonsaphenofemoral junction causes of the reflux are common. The most common is reflux beginning just inferior in relation to the inflow of incompetent inner thigh external pudendal varicose veins in multiparous women. Reflux can also begin below the inflow of an incompetent midthigh incompetent perforating vein. Sometimes reflux that initiates in the anterior accessory GSV at the saphenofemoral junction will be the cause of reflux in the GSV only below the inflow of some of the anterior accessory GSV refluxing tributaries in the mid to lower thigh. Similarly, peripatellar and paratibial incompetent perforating veins and refluxing tributaries from the small saphenous vein can cause GSV reflux in the lower leg. Next the patient is turned away from the examiner and the small saphenous vein is evaluated (Fig. 6B). The process of evaluation is similar to that of the GSV. This usually begins by finding the small saphenous vein in the saphenous space in the upper third of the calf. Then the course of the small saphenous vein is traced, assessing its diameter as well as its relationship to any varicose tributaries and the popliteal vein. As mentioned previously, in most patients, the small saphenous vein also connects with a thigh extension of variable length that runs in the saphenous space on the posterior aspect of the thigh. The small saphenous vein, any thigh extension, and the saphenopopliteal junction are each assessed with color Doppler ultrasound and pulsed-wave Doppler imaging. An evaluation of the femoral vein and the popliteal veins for reflux and obstruction should be included in the examination. Evaluation for reflux is done in the standing or in reverse Trendelenburg position using a similar technique to that used for evaluation of the superficial veins. Usually, the femoral and popliteal veins can be evaluated in one location each. Common femoral vein and popliteal vein reflux are defined as retrograde flow in these veins after the release of calf compression lasting longer than 1 second [12]. The ipsilateral and contralateral common femoral vein waveforms should be evaluated in each case to offer the best opportunity to identify an obstruction of the iliac vein outflow [13, 14]. Performing this evaluation bilaterally is important to identify asymmetric tracings that have a stronger prognostic significance. Acquiring the tracings can be done with the patient standing, but the flow through the common femoral vein in response to respirations will be more dramatic with the patient in the supine or mildly reverse Trendelenburg position. A normal common femoral vein waveform should show respiratory variability in flow. Observation during breathing at rest (and, if necessary, during deep inspiration and expiration) will usually show the variability. Right atrial pulsations are often seen as well. Either cardiac pulsations or respiratory variability are indicative of a patent path between the common femoral vein and the heart. If there is no variability in one common femoral vein with only continuous flow in the other, the possibility of an iliac vein outflow obstruction exists on the continuous flow side [13, 14] (Fig. 8). Direct duplex ultrasound imaging of the external and common iliac veins can be performed to evaluate suspected intrinsic or extrinsic venous abnormalities inferred by an abnormal common femoral vein waveform. The common and iliac veins can be directly imaged in many if not most patients, especially when using oblique positioning. A criterion based on a velocity ratio at the level of a narrowing and in an adjoining normal segment to distinguish significant and nonsignificant stenosis has been proposed [15]. However, this criterion has only been validated in a small heterogeneous population to date and is not widely accepted. In many cases, duplex ultrasound in patients with varicose veins will not identify saphenous vein incompetence, or the saphenous reflux found may not explain all of the AJR:202, March 2014 635

Khilnani varicose pathways. Nonsaphenous pathways, which are the only explanation for varicose veins in at least 10% of patients, are much more common in multiparous women [16]. These nonsaphenous pathways are also frequently found in addition to saphenous reflux in a given limb. The most common of these pathways are pudendal and gluteal vein incompetence. Varicose veins that travel along the sciatic nerve are responsible for lateral calf varicose veins in about 1% of patients, almost exclusively multiparous women [16, 17)]. Incompetent perforating veins in the medial and lateral thigh and the popliteal fossa are another important source of nonsaphenous reflux. An exhaustive search and evaluation of perforating veins and evaluation of the calf veins for patency and reflux need not be part of routine examination in most cases of chronic venous disease. In patients with venous ulcers, the identification of an incomplete perforating vein in proximity to the ulcer may have clinical relevance. Therefore a more thorough search in these patients is required. Pathological perforators is a recently popularized term to represent the characteristics of perforating veins that require treatment in patients with CEAP clinical stage C5 and C6. These are incompetent perforators in the vicinity of and directing venous pressure to the region of a venous ulcer that does not heal despite elimination of other pathways of superficial reflux and the use of compression [18]. The commonly accepted criterion for significant reflux in perforating veins is 0.3 second of retrograde flow after release of compression of a vein segment below the perforator [12]. Most perforating veins in the lower calf that are larger than 3.5 mm in diameter reflux [18]. When describing perforating veins, they should be named on the basis of their location using the new nomenclature. For posterior tibial perforating veins, the distance from the floor is a valuable supplemental way to document the location. The complete examination of the deep venous system is beyond the scope of this article, in which the focus is to describe the examination of the superficial venous system of the leg. However, a careful evaluation of the deep system is an important component. In patients with isolated unexplained pain or swelling, the analysis of the deep veins, including the common femoral veins, may be the most important part of the evaluation. Briefly, the examiner should evaluate the deep veins to look for incompetence, areas of vein narrowing, occlusion, or collaterals that are the result of prior thrombosis. A careful search for more subtle evidence of prior thrombosis, such as webs, wall thickening, and calcification, is also important. In this case, the goal is to identify those patients who have had a deep venous thrombosis (DVT) in the past and to determine whether any hemodynamically important persistent venous obstructions persist to contribute to venous hypertension. Duplex Ultrasound After Treatment The goals of duplex ultrasound evaluation after treatment vary with the different treatments used and for the time after treatment at which they occur. Early after all treatment, duplex ultrasound is used to check for satisfactory closure of the targeted segments as well as to identify a thrombotic complication. Deep venous thrombosis after ablative GSV procedures occurs about 1% of the time at the connections between the deep and superficial veins and less likely in places in which spontaneous deep venous thrombosis occurs [19]. To identify these asymptomatic junctional thrombus extensions into the deep vein, duplex ultrasound needs to be performed early after ablation. A growing body of evidence shows that most of these junctional thromboses are self-limited and do not require treatment. However, consensus for management of these abnormalities is still evolving. A system to categorize the extent of thrombus extension into the femoral and popliteal veins after thermal ablation is a useful tool to communicate such findings. In this categorization, a thrombus up to the deep junction is called an endovenous heat induced thrombosis or EHIT 1 ; those into the femoral or popliteal vein but occluding less than or more than 50% of the cross-sectional diameter are EHIT 2 and EHIT 3, respectively; and the thrombus is EHIT 4 when it results in complete occlusion [20] (Fig. 9). In asymptomatic patients, an evaluation of the deep system is generally included when duplex ultrasound is performed, although the incidence of such deep venous thrombosis in this population is quite small. In symptomatic patients (those with swelling or pain away from the sites being treated or with significant superficial phlebitis), the entire deep system should be carefully evaluated. Another possible complication after thermal ablation is an arteriovenous fistula (AVF) [21]. These can occur when the lumens of the target vein and an adjacent artery communicate and may be caused by a needle stick or thermally induced lesion. AVFs can lead to partially patent vein segments that have pulsatility on duplex ultrasound after treatment. This has been described between the proximal small saphenous vein and the sural artery branch of the popliteal artery and between the superficial external epigastric artery and proximal GSV [22]. An AVF between the GSV and a small unnamed artery in the upper thigh has been reported [23]. After thermal ablation, the treated vein segments will have no flow early after treatment and ideally show thick vein walls and a small noncompressible lumen (Fig. 10). There should be no flow in the entire treated vein segment. This should be distinguished from the appearance of a thrombosed vein that, in the first few weeks, should appear as a central hypoechoic to moderately hyperechoic filling defect. Partially thrombosed veins may have some flow (Fig. 11). Thrombosed veins are more likely to recanalize than thickwalled veins over the ensuing few months. The size of the vein early after thermal ablation will often be the same or modestly smaller than before treatment and can transiently become larger. Over the course of the next few months, a successfully treated vein will shrink in diameter. By 12 months after treatment, adequately treated veins will cicatrize to the point that the vein will be difficult to identify on duplex ultrasound and have no flow [19] (Fig. 12). After ultrasoundguided sclerotherapy (chemical ablation), postprocedure ultrasound is also used to ascertain the outcome. Early after sclerotherapy, veins appear thrombosed. Successfully sclerosed veins will shrink, similar to a thermally ablated vein. Recanalization of previously closed vein segments can occur and may be evident on duplex ultrasound before the effects on tributary veins downstream are noticed. Most treatment failures after both thermal and chemical ablation will be evident in the first few weeks as either thrombosed vein segments that subsequently recanalize or as veins that appear unchanged from before treatment. Most GSV thermal and chemical ablation treatment failures are segmental, beginning at the saphenofemoral junction and extending downward a variable length to the takeoff of an incompetent tributary. Below this level, the vein is often successfully treated. Occasionally on long-term evaluation, the targeted vein may be segmentally patent but will no longer have reflux [19]. 636 AJR:202, March 2014

Chronic Venous Disease of the Lower Extremities Reporting A report of the findings of the duplex ultrasound examination should be created and archived in the medical record. Although reporting formats are variable, they should clearly communicate the leg examined; describe the criteria, technique, and positions used; and delineate pertinent positive and negative findings. High-quality reports should conform to the standards published by the ACR and other accrediting bodies for duplex ultrasound practice. In addition, the images created during the examination must be archived in either hardcopy or PACS [5]. Conclusion The ultrasound examination of patients with chronic venous disease requires a thorough evaluation of the superficial veins to identify all of the patterns of incompetence. It also requires a detailed examination of the deep venous system to identify any evidence of prior DVT or extrinsic compressions. Duplex ultrasound requires the examiner to solve a puzzle to explain the patient s clinical manifestations. Patients treated with surgery, thermal ablation, or ultrasound-guided sclerotherapy will require duplex ultrasound after treatment to identify complications, gauge the extent of success, and evaluate the cause for any recurrence. References 1. Coleridge-Smith P, Labropoulos N, Partsch H, Myer K, Nicolaides A, Cavezzi A. Duplex ultrasound investigation of the veins in chronic venous disease of the lower limbs: UIP consensus document. Part 1. Basic principles. Eur J Vasc Endovasc Surg 2006; 31:83 92 2. Min RJ, Khilnani NM, Golia P. Duplex ultrasound evaluation of lower extremity venous insufficiency. J Vasc Interv Radiol 2003; 14:1233 1241 3. American College of Radiology website. ACR- AIUM-SRU practice guideline for the performance of peripheral venous ultrasound examinations. www.acr.org/~/media/acr/documents/pgts/ guidelines/us_peripheral_venous.pdf. Revised 2010. Accessed November 1, 2013 4. Intersocietal Accreditation Commission website. IAC standards and guidelines for vascular testing accreditation. intersocietal.org/vascular/standards/ IACVascularTestingStandards2013.pdf. Updated June 13, 2013. Accessed November 1, 2013 5. American College of Radiology website. Accreditation. www.acr.org/quality-safety/accreditation. Accessed November 1, 2013 6. Intersocietal Accreditation Commission website. Accreditation evolved. www.intersocietal.org/iac/ accreditation/whatisaccreditation.htm. Accessed November 1, 2013 7. Eklöf B, Rutherford RB, Bergan JJ, et al. Revision of the CEAP classification for chronic venous disorders: consensus statement. J Vasc Surg 2004; 40:1248 1252 8. Caggiati A, Bergan JJ, Gloviczki P, et al. Nomenclature of the veins of the lower limbs: an international interdisciplinary consensus statement. J Vasc Surg 2002; 36:416 422 9. Caggiati A, Bergan JJ, Gloviczki P, et al. Nomenclature of the veins of the lower limb: extensions, refinements, and clinical application. J Vasc Surg 2005; 41:719 724 10. Coleridge-Smith P, Labropoulos N, Partsch H, et al. Duplex ultrasound investigation of the veins in chronic venous disease of the lower limbs: UIP consensus document. Part 2. Anatomy. Eur J Vasc Endovasc Surg 2006; 31:83 92 11. Yamaki T, Nozaki M, Sakurai H, et al. Comparison of manual compression release with distal pneumatic cuff maneuver in the ultrasonic evaluation of superficial venous insufficiency. Eur J Vasc Endovasc Surg 2006; 32:462 467 12. Labropoulos N, Tiogson J, Pryor L, et al. Definition of venous reflux in lower-extremity veins. J Vasc Surg 2003; 38:793 798 13. Bach AM, Hann LE. When the common femoral vein is revealed as flattened on spectral Doppler sonography: is it a reliable sign for diagnosis of proximal venous obstruction? AJR 1997; 168:733 736 14. Lin EP, Bhatt S, Rubens D, Dogra VS. The importance of monophasic Doppler waveforms in the common femoral vein: a retrospective study. J Ultrasound Med 2007; 26:885 891 15. Labropoulos N, Borge M, Peirce K, Pappas PJ. Criteria for defining significant central venous stenosis with duplex ultrasound. J Vasc Surg 2007; 46:101 107 16. Malgor RD, Labropoluos N. Pattern and types of non-saphenous vein reflux. Phlebology 2013; 28(suppl 1):51 54 17. Gianesini S, Menegatti E, Tacconi G, et al. Echoguided foam sclerotherapy of venous malformation involving the sciatic nerve. Phlebology 2009; 24:46 47 18. Gloviczki P, Comerota AJ, Dalsing MC, et al. The care of patients with varicose veins and associated chronic venous diseases: clinical practice guidelines of the Society for Vascular Surgery and the American Venous Forum. J Vasc Surg 2011; 53(5 suppl):2s 48S 19. Khilnani NM, Grassi CJ, Kundu S, et al. Multi-society consensus quality improvement guidelines for the treatment of lower-extremity superficial venous insufficiency with endovenous thermal ablation from the Society of Interventional Radiology, Cardiovascular Interventional Radiological Society of Europe, American College of Phlebology, and Canadian Interventional Radiology Association. J Vasc Interv Radiol 2010; 21:14 31 20. Dexter D, Kabnick L, Berland T, et al. Complications of endovenous lasers. Phlebology 2102; 27(suppl 1):40 45 21. Timperman PE. Arteriovenous fistula after endovenous laser treatment of the short saphenous vein. J Vasc Interv Radiol 2004; 15:625 627 22. Rudarakanchana N, Berland T. Chasin Cara, et al. Arteriovenous fistula after endovenous ablation for varicose veins. J Vasc Surg 2012; 55:1492 1494 23. Martin EC, Todd GJ. Embolization of an arteriovenous fistula after radiofrequency ablation (RFA) of the saphenous vein. 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Khilnani Fig. 1 Diagram shows great saphenous vein and its important tributaries. A Fig. 2 Diagram shows small saphenous vein and its important tributaries. Fig. 3 Axial ultrasound images of great saphenous vein (A) and small saphenous vein (B) in saphenous compartment superficial to deep and deep to superficial fascia. Asterisk shows vein, and black and white arrows superficial and deep fascia, respectively. B 638 AJR:202, March 2014

Chronic Venous Disease of the Lower Extremities Fig. 5 Axial ultrasound image of great saphenous vein (asterisk, A) in saphenous compartment and adjacent tributary (arrowhead) superficial to saphenous compartment. Coronal drawing (B) shows enlarged refluxing saphenous vein within oval saphenous compartment and refluxing tributary (dark gray shading) after it passes through superficial fascia. Two adjacent axial depictions show enlarged saphenous vein in saphenous compartment (top) and more normal-caliber saphenous vein in saphenous compartment and enlarged refluxing tributary (dark gray shading) just outside (bottom). Fig. 4 Anterior accessory great saphenous vein (GSV). Axial ultrasound image about 2 cm below saphenofemoral junction shows positions of GSV (0.68 cm, measured with +) and anterior accessory GSV (0.55 cm, measured with x). The anterior accessory GSV travels roughly parallel to GSV but more anteriorly, superficial to femoral vein and superficial femoral artery. A B AJR:202, March 2014 639

Khilnani Fig. 6 Photograph (A) shows patient position for examination of great saphenous vein. Ultrasound probe is steeply angled to allow use of Doppler analysis to determine direction of blood flow during and after manual compression of calf. Photograph (B) shows patient position for examination of small saphenous vein with probe steeply angled for Doppler analysis of blood flow direction after squeezing calf and then after releasing squeeze. A B Fig. 7 Pulsed-wave Doppler image of great saphenous vein in axial projection shows significant retrograde blood flow after release of manual calf compression. Reflux duration can be easily quantified with ultrasound probe angled steeply upward while imaging in axial projection. 640 AJR:202, March 2014

Chronic Venous Disease of the Lower Extremities A B A Fig. 8 Pulsed-wave Doppler tracing. A, Pulsed-wave Doppler tracing of common femoral vein shows normal respiratory variability. B and C, Pulsed-wave Doppler tracings in prior left iliofemoral deep venous thrombosis show left common femoral vein (B) has continuous flow waveform, with no respiratory variability. Right common femoral vein waveform (C) shows respiratory and cardiac variability. Contrast-enhanced pelvic MR venogram (not shown) showed webs and vein narrowing in left common and external iliac veins and normal right iliac venous system. Fig. 9 Thrombus extension from left great saphenous vein (GSV) into common femoral vein on ultrasound 8 weeks after endovenous thermal ablation (endovenous heat induced thrombosis ([EHIT 3]). A, Longitudinal ultrasound image shows thrombus beginning in GSV and extending more than 2.5 cm into deep vein (asterisks). B, Axial ultrasound image shows that thrombus occupies more than 50% of cross-sectional area of common femoral vein. Thrombus is outlined by asterisks. B C AJR:202, March 2014 641

Khilnani Fig. 10 Axial ultrasound image of upper thigh great saphenous vein 1 month after endovenous thermal ablation shows slightly echogenic thick-walled vein and very small hypoechoic lumen that is not compressible and has no demonstrable Doppler flow. This is optimal appearance of thermally ablated vein 4 12 weeks after treatment. Fig. 11 Axial ultrasound image of great saphenous vein thrombosis shows echogenic nonocclusive thrombus and thin-walled vein. On duplex analysis (not shown), there was flow in compressible lumen surrounding thrombus. FOR YOUR INFORMATION Fig. 12 Longitudinal color Doppler image of saphenofemoral junction in 1 year after great saphenous vein (GSV) endovenous thermal ablation. Saphenofemoral junction remains patent and conducts antegrade flow from its junctional branches toward common femoral vein. GSV in treated segment below this level is thin cord, measured in this image, and has no demonstrable flow. This article is available for CME and Self-Assessment (SA-CME) credit that satisfies Part II requirements for maintenance of certification (MOC). To access the examination for this article, follow the prompts associated with the online version of the article. 642 AJR:202, March 2014