Approach to pelvic venous disorders

Sources of information

This review is based on guidelines from the American Venous Forum (AVF),^6-9 the Society for Vascular Surgery,^7-9 the American Vein and Lymphatic Society,^7-9 the Society of Interventional Radiology,^8,9 and the European Society for Vascular Surgery.¹⁰ These sources provide comprehensive recommendations for the diagnosis, management, and referral of patients with PeVDs.

Main message

The 2024 AVF guidelines recommend that female patients with CPP of unknown origin be evaluated for PeVDs (grade 1B evidence).⁶ Table 1 presents a summary of the symptoms and pathophysiology of PeVDs as well as relevant imaging findings.⁸

Clinical presentation. PeVDs are linked to venous reflux or obstruction affecting interconnected venous plexuses, resulting in symptoms in the pelvis or lower limbs. Historically, conditions such as pelvic congestion syndrome, nutcracker syndrome, and May-Thurner syndrome were treated as distinct entities, but they are now recognized as part of the PeVDs spectrum.¹¹ PeVDs include the following 4 clinical presentations:

Renal symptoms of venous origin: Renal venous hypertension (formerly called nutcracker syndrome) occurs when the left renal vein is compressed between the aorta and superior mesenteric artery, causing back pain, hematuria, and varicosities in or around the kidney.¹² This pressure can also lead to orthostatic proteinuria. In patients with more advanced cases, blood flow may be rerouted through the lumbar or ovarian veins, which can contribute to CPP of venous origin.

CPP of venous origin: CPP due to venous insufficiency typically affects female patients between 20 to 45 years of age, particularly those who have had multiple pregnancies.^13,14 The outdated term for this phenomenon is pelvic congestion syndrome. The pain is usually dull, noncyclic (unrelated to the menstrual cycle), and worsens with standing, with walking, or during menstruation.¹¹ The presence of postcoital ache and tenderness over the ovarian point (the junction of the upper and middle thirds of a line drawn between the anterior superior iliac spine and umbilicus) has been reported to be 94% sensitive and 77% specific for distinguishing venous origin pelvic pain from other pelvic pathologies.³

Varicose veins in the perineal and lower limb areas: PeVDs can cause varicose veins in the perineum, vulva, and thighs due to venous reflux in the ovarian or internal iliac veins.¹¹ Symptoms of these varicosities include pain, feelings of heaviness, itchiness, or inflammation. In some patients varicosities in the legs originate from pelvic venous reflux rather than from the typical leg veins, such as the greater saphenous vein, which can lead to misdiagnosis if the pelvic source is overlooked.

Venous claudication: May-Thurner syndrome is the outdated term used to describe a situation where the left iliac vein is compressed by the overlying right iliac artery, leading to decreased outflow from the left leg.¹⁵ This results in symptoms such as leg swelling, pain with walking (venous claudication), and the development of varicosities or deep vein thrombosis. The increased venous pressure from this compression can also contribute to CPP of venous origin. Chronic iliac vein deep vein thrombosis without May-Thurner syndrome is also a cause of venous obstruction and can lead to a similar presentation.

Diagnostic approach. Diagnosis of PeVDs requires clinical suspicion, especially in patients with CPP and no clear gynecologic cause. Differential diagnoses for patients with CPP may include endometriosis, interstitial cystitis, irritable bowel syndrome, musculoskeletal pain, and psychological factors. Recognizing the hallmarks of PeVDs can help narrow the differential, particularly in multiparous patients with noncyclic pelvic pain and perineal varicosities. A combination of clinical examination and imaging tests is crucial.

Guidelines recommend Doppler ultrasound, both transabdominal and transvaginal, as the first imaging test to use to evaluate pelvic and lower extremity varicosities (grade 1 level B evidence).^6,7 These tests look for dilated veins (ovarian veins greater than 6 mm, extrapelvic veins greater than 3 mm) with slow or reversed blood flow, which can indicate venous insufficiency. Transvaginal ultrasound has a sensitivity of 92% to 100%.^1,16 When the patient has varicose veins around the perineum or vulva, guidelines recommend using ultrasound to map out the affected veins and determine the best treatment approach (grade 1 level C evidence).¹⁰ Specific veins (eg, pudendal, obturator, gluteal) may have abnormal blood flow, and imaging can help identify any points where blood reflux is occurring between the pelvis and lower limbs. In patients with renal venous hypertension, substantial compression of the renal vein is suspected if blood flow in the compressed area is much faster than in other parts of the vein.¹⁷ Iliac venous obstruction is defined as greater than 50% cross-sectional area reduction of the common or external iliac veins.¹⁸ However, this finding may be present in one-quarter to one-third of the general population.¹⁹ As a result, this must be interpreted in the context of the patient’s clinical presentation.

If ultrasound findings are inconclusive, computed tomography or magnetic resonance imaging can provide more detailed images of the pelvic veins to help identify varicosities and reflux. Magnetic resonance venography is particularly useful for evaluating ovarian, iliac, and pelvic floor veins. In a small prospective study conducted in Germany, magnetic resonance venography was found to detect PeVDs in ovarian veins, internal iliac veins, and pelvic floor veins with a sensitivity of 88%, 100%, and 91%, respectively.²⁰

Venography is the criterion standard for diagnosing PeVDs, but it is more invasive and typically reserved for patients for whom other imaging results are unclear or used prior to interventional procedures. It can directly demonstrate venous reflux and obstruction and thereby help guide treatment. In addition, venography allows for pressure measurement within veins, which may be necessary to confirm diagnoses.^21,22

Access to imaging tests may vary between centres. In some institutions pelvic vein assessment by ultrasound is not routinely available due to technological limitations. Primary care physicians should recognize that advanced imaging tests are often initiated by vascular specialists based on local expertise and practice patterns.

Treatment. The goal of therapy for patients with PeVDs is to reduce or eliminate the interconnected varicosities of the abdomen, pelvis, and lower extremities responsible for their symptoms. Treatment strategies should be tailored to the patient’s underlying subtype of PeVDs (eg, venous reflux, renal vein compression, iliac outflow obstruction). Each subtype may respond differently to interventions, and combined pathology may require a multimodal approach. Many treatments have been attempted, from pharmacologic approaches to open surgery.

Hormone therapies, such as goserelin (a gonadotropin-releasing hormone antagonist) or medroxyprogesterone acetate, have been used with limited success.²³ Goserelin was shown to be more effective than medroxyprogesterone acetate but neither was shown to eliminate pelvic pain. In addition, their benefits tend to disappear after discontinuation, and side effects such as hirsutism and reduced libido limit their use. A placebo-controlled study conducted in Russia found that micronized purified flavonoid fraction improved symptoms and quality of life in female patients with PeVDs by reducing pain and improving physical and psychological health.²⁴ However, long-term effectiveness of micronized purified flavonoid fraction is unclear.

For patients with substantial or refractory symptoms, interventional treatments are highly effective. Coil embolization is the most common treatment for patients with symptomatic PeVDs, and this approach is supported by the most recent guidelines from the AVF and the European Society for Vascular Surgery.^6,10 The procedure involves placing coils in the affected veins (often ovarian veins) to block reflux. It has shown high success rates, with 3 studies from various countries finding most patients reported complete or substantial symptom relief.^25-27 One long-term study conducted in Germany with 3 years of follow-up has shown patients’ pain scores drop significantly after coil embolization of ovarian veins.²⁸ Sclerotherapy, often used alongside embolization, involves injecting a sclerosant to collapse varicosities. One study conducted in Italy found sclerotherapy to be effective in providing significant symptom relief.²⁹

When varicose veins in the vulva and lower limbs are caused by venous reflux from the pelvis but the patient lacks typical symptoms of CPP, guidelines recommend local treatments such as ultrasound-guided foam sclerotherapy rather than pelvic vein embolization (grade 2a level C evidence).¹⁰ Pelvic vein embolization should be reserved for patients with pelvic symptoms. Foam sclerotherapy can also be used to treat any extrapelvic varicose veins that remain after the main pelvic veins have been embolized. In patients with combined saphenous reflux and pelvic origin varicosities, guidelines recommend treating the refluxing saphenous vein with ablation and using phlebectomy or ultrasound-guided foam sclerotherapy for the varicosities (grade 1 level C evidence).⁷

For patients with venous obstruction, guidelines recommend endovascular treatment as first-line therapy in cases of iliac vein outflow obstruction with severe symptoms.¹⁰ Iliac vein stenting can relieve the obstruction and improve both pelvic and lower extremity symptoms.^30-33 Treatment of left renal vein compression is more complex and typically requires a multidisciplinary approach.¹⁰ Historically, open and laparoscopic surgery have been used to relieve renal venous hypertension, but more recently endovascular stenting has been proposed.³⁴ This approach usually leads to quick recovery and symptom relief, although in 1 study conducted in China, stent migration occurred in 6.7% of cases over a follow-up period with a mean duration of 55 months.³⁵

Referral. Family physicians should refer patients with confirmed pelvic venous reflux or obstruction to a vascular specialist or interventional radiologist when conservative measures fail. It is important to identify vascular specialists with specific expertise in PeVDs, as not all centres are equipped to provide comprehensive care. Partnerships with gynecologists—especially those focused on CPP—can also enhance diagnosis and streamline care for these patients. Referral is particularly important for patients with disabling symptoms that affect their quality of life.