Pelvic Veins and the Lower Extremity

For the treating physician, there is nothing more satisfying than transforming a patient with severe symptomatic superficial venous disease into an asymptomatic vein-free individual. Conversely, there is nothing more frustrating than the patient who has no symptomatic improvement after treatment or has persistence or early recurrence of varicosities. This latter group of patients, which can be found in most phlebology practices, often has complex venous disease that does not arise from the saphenous system. The origin of the disease is typically overlooked, particularly when its derivation is in the pelvis. Refluxing pelvic vessels can join saphenous veins causing segmental reflux that is confused for primary saphenous disease. This erroneous diagnosis can lead to ineffective and potentially unneeded therapies. Additionally, even when the pelvic source is recognized, the diagnostic workup and best method of treatment may be unknown to many clinicians. For these reasons, it is imperative that the practicing phlebologist be able to recognize this disorder and be acquainted with the appropriate work-up algorithm.

Prevalence

Pelvic-derived lower extremity varicosities are more common than most clinicians appreciate. In general, nonsaphenous venous reflux occurs in about 10% of patients.
More than one third of this group has varicosities that arise from the pelvis1. In a recent study, 1350 patients with lower extremity varicosities were evaluated with both duplex ultrasound and CT venography to ascertain the source of reflux. A pelvic reflux source was noted in 8.6% of patients2. In another study, 741 female patients with varicose veins from two separate clinics were evaluated with duplex and transvaginal ultrasound. These studies found a pelvic reflux source in 19.5% of patients in one group and 21.5% in the other. Approximately 80% of the pelvic reflux patients were noted to have reflux in the gonadal vein3. Multiple additional studies show similar results leading to the conclusion that approximately one in every five female patients will have lower extremity varicosities as a result of pelvic venous disease.

Etiology

Pelvic-derived lower extremity varicosities have many different etiologies. These etiologies can be split into two broad categories—venous reflux and venous obstruction. Pelvic venous reflux, which is the more common cause of lower extremity varicosities, can result from venous insufficiency in gonadal veins or the internal iliac veins. In addition, pelvic or vaginal venous malformations can cause sufficient reflux to generate lower extremity varicosities4. Obstructive processes, such as May-Thurner syndrome, Nutcracker syndrome, and IVC obstruction, cause mechanical venous hypertension and the formation of varicose collaterals5-8.The value of knowing the etiology is important for determining the treatment strategy. Patients who have an obstructive process will require a procedure to revascularize the obstructed vessel. In the case of May- Thurner syndrome, this may necessitate the placement of an iliac stent9. This is a very different strategy than that needed for the treatment of venous insufficiency. Typically, pelvic venous insufficiency is treated with occlusion of the abnormal refluxing vessels.

Clinical presentation

Pelvic venous disease classically presents with a constellation of symptoms that have been described as pelvic congestion syndrome. These symptoms include abdominal fullness, postural pelvic pain and heaviness, dyspareunia, post-coital pain, dysmenorrhea, bladder irritation and urgency10-12. However, patients who present to the phlebologist rarely complain of these symptoms. More commonly, patients present with symptoms typical of superficial venous disease which include lower extremity achiness, fatigue and varicosities (Fig 1). A complaint of vaginal varicosities may be the only tip-off that the patient’s problem originates in the pelvis. However, many patients are sometimes unaware that they have vaginal varicosities and may not provide this history. It is, therefore, very important that an assessment of
the vaginal region be performed during the lower extremity ultrasound examination.

Imaging

For patients who present with significantlower extremity venous insufficiency, a duplex ultrasound examination is mandatory. Duplex ultrasound is excellent at imaging the saphenous and deep venous system. When upper thigh varicosities are noted, it is essential that this reflux be traced to its point of origin. Often these vessels can be
tracked into the vaginal or perineal regions indicating the presence of pelvic venous disease. Once pelvic venous disease is detected, transabdominal ultrasound imaging
can be performed looking for pathology in the iliac or gonadal veins which may be all that is needed to make the correct diagnosis. If the patient’s size limits the ability to visualize these structures with ultrasound, then other imaging modalities can be considered. Transvaginal ultrasound, magnetic resonance imaging and CT imaging all have the ability to better visualize structures within the pelvis. Each of these modalities has advantages and disadvantages. Magnetic resonance venography can produce spectacular images of the pelvic vasculature if it is done properly (Fig 2)13-16. Unfortunately, this expensive and lengthy exam is very technique dependent, and obtaining quality studies can be inconsistent. Contrast enhanced CT imaging is readily available, but up until recently, was not as good as MR at visualizing venous structures in the pelvis17. With the new advanced multislice scanners, image quality and speed of examination has dramatically improved. Using appropriate contrast bolus timing diagnostic CT images of the pelvic venous anatomy can be consistently obtained18-21. Transvaginal ultrasound is another excellent pelvic imaging tool22. Although it does not use contrast or ionizing radiation, it is unable to image the iliac or renal vessels as well as the other modalities and is slightly more invasive.

Treatment Strategies

The classical approach to lower extremity venous reflux is to start therapy from the point of origin downward. Applying this topdown concept to pelvic vein reflux leads to an algorithm where secondary imaging is needed to find the reflux origin and, once found, treated. In the case of gonadal vein reflux this may involve obtaining an MR or CT venogram and then embolization of a refluxing gonadal vessel. In my experience, this therapeutic approach is effective in remedying an individual with pelvic symptoms, but frequently ineffective in patients whose symptoms are confined to the lower extremities. Offering a therapy that presumably improves venous physiology but has no perceivable benefit leads to patient frustration and dissatisfaction. To avoid this problem, we have adopted a bottom-up approach where the varicosities exiting the pelvis are treated first. With this method, the perineal and vulvar varicosities are occluded with a sclerosant that can be delivered with standard injections or with fluoroscopic guidance. To better understand this idea, a conceptualization of pathologic pelvic venous anatomy is helpful (Fig 3). In this image, reflux beginning in the gonadal vein extends in to the peri-uterine varicose plexus where it collateralizes with the internal iliac veins. From this complex network, vessels extend down into the lower extremities causing varicosities and symptoms. If an imaginary line is drawn through the middle of the peri-uterine varicose plexus, it is the varicosities above this line (upper component) that
are responsible for pelvic symptoms while lower extremity symptoms are caused by the varicosities below (lower component). Occlusion of the upper component vessels will not improve symptoms of venous incompetence in the leg, as the countless number of valveless internal iliac vein collateral connections will continue to supply an abundance of bloodflow. It is for this reason that many published series do not demonstrate significant clinical improvement in lower extremities symptoms after gonadal vein embolization alone 23, 24.

With the algorithm previously described, the choice of treatment depends initially on the patient’s clinical symptoms. If symptoms are confined to the extremities, then treatment of the lower component is offered. This treatment can be in the form of ultrasound-guided injections. However, the lower component varicosities can sometimes be so extensive that this approach fails. In this situation, fluoroscopically guided embolization permits the safe administration of large volumes ofsclerosants and increases success rate dramatically. This technique is not only an effective treatment method but is also an excellent diagnostic tool. The preliminary varicography can often distinguish between different etiologies obviating the need and cost of secondary imaging (Fig 3, 4, 5). Once the lower component is successfully treated, any additional therapy will depend on the patient’s clinical follow-up. If after several weeks they still have persistent symptoms or if they develop recurrent varicosities, then it may be necessary to treat the upper component. At this point secondary imaging, if needed, can be obtained followed by gonadal vein embolization. In my experience, with this approach, less than 20% of patients will return for any secondary imaging or procedures even when followed for several years.

Treatment Technique

Upper Component

Transcatheter embolization of the gonadal vein has been extensively described and an overly detailed description is beyond the scope of this article.25-31. In my practice a transjugular route is used, as this provides easier access to the gonadal veins. After placing a 45 cm 6Fr vascular sheath, the left renal vein is catheterized and a contrast injection is performed. If gonadal vein reflux is noted, the vein is selected and the catheter is advanced to the level of the peri-uterine varicose plexus (Fig. 6). The 6Fr vascular sheath is then advanced over the catheter into the gonadal vein. A 5.5Fr balloon occlusion catheter is then advanced through the sheath and positioned in the distal gonadal vein. The occlusion balloon is gently inflated and a contrast venogram is performed to assess the volume needed to fill the peri-uterine venous plexus (Fig. 7). Once the anatomy is identified, sodium tetradecyl sulfate is mixed with contrast to make a 1.5% solution. This solution is then injected through the balloon occlusion catheter to fill as much of the plexus as possible. This is performed under fluoroscopic guidance and the injection is immediately halted when leakage into normal deep veins is noted. The volume of sclerosant needed to fill the plexus is often greater than 20 ml. After the plexus is filled, a series of coils are deposited to occlude the distal gonadal vein and trap the sclerosant mixture in place. The occlusion balloon is deflated and retracted with the sheath to the origin of the gonadal vein. The balloon is then reinflated and the sclerosant contrastmixture is injected to fill the entire gonadal vein after which additional coils are deposited, trapping the sclerosant in place and completing the embolization (Fig. 8). Any additional abnormal refluxing vessels, such as the right gonadal vein, are sought out and embolized in a similar fashion.

Lower component

Embolization of the lower component has not been extensively described. This technique involves ultrasound identification of the deeper vaginal varicosities and then the insertion of a needle directly into these vessels. With the needle in position, contrast is injected and a venogram is performed. Once the full extent of the abnormality is
identified, a 1.5% sodium tetradecyl sulfate and contrast solution is injected under fluoroscopic guidance. Care is taken to avoid inadvertent leakage of the sclerosant mixture into normal deep venous structures. In cases of gonadal vein reflux it is not unusual for this mixture to fill the peri-uterine venous plexus and on occasion, the lower portions of the gonadal veins. The mixture is allowed to remain within the varicosities for 15-20 minutes until fluoroscopic evidence of venous occlusion is noted (Fig. 9).

Conclusion

The treatment and workup of pelvic derived lower extremity varicosities should be completely
dependent on the patient’s clinical presentation. If pelvic symptoms predominate, then the upper component of the pathologic venous plexus should be treated initially. If extremity symptoms predominate, then the lower component should be treated first. This may be as simple as injection sclerotherapy alone. If injections are not effective, then lower component embolization would be the next best step. If this treatment solves the patient’s problems, then no additional treatment or workup is required. If however, the patient has persistent symptoms or early recurrence of varicosities, then treatment of the upper component should be considered. With this approach, secondary imaging is not needed until the decision to treat is made. Overall, this algorithm is both cost and clinically effective and has resulted in great patient satisfaction.