Published clinical success and low morbidity with gonadal vein embolization

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By Sandeep Bagla

Pelvic congestion syndrome (PCS) is an often overlooked diagnosis of pelvic pain, representing 15% of all outpatient gynaecological visits and 30% of those for pelvic pain. Unfortunately, patients frequently undergo an exhaustive evaluation before being diagnosed with PCS or being referred to interventional radiology. Pelvic congestion with varices was first described more than 150 years ago, and became associated with a psychosocial condition more than 50 years ago. Thereafter, the pathophysiology of PCS was described, with further anatomical understanding in more recent decades. Negative psychosocial associations with the term pelvic congestion syndrome has led to pelvic venous insufficiency (PVI) as the preferred term for describing the underlying pathophysiology of the condition.

Typically multiparous women usually present between the ages of 20 and 45 with chronic pelvic pain of greater than six months duration, exacerbated by prolonged sitting or standing. Pain is described as dull, heavy and aching, worsened with menses or sexual activity (dyspareuenia). On exam, patients may present with visible labial, vulvar or pudendal varices often with extension of varices to the posterior medial thigh or gluteal regions. In addition, one in seven women with lower extremity varicose veins are found to have underlying PVI.

Although the aetiology of pelvic congestion syndrome is poorly understood, the primary abnormality is the absence of functioning valves in the ovarian or internal iliac vein branches. This likely congenital absence of valves or hereditary predisposition is the most common explanation. The condition is worsened with each successive pregnancy due to increase blood volume, hormonal fluxes and even possible subclinical thrombosis of these veins. Other less common aetiologies are secondary to uterine malposition and the nutcracker syndrome of left renal vein compression between the aorta and the superior mesenteric artery.

Imaging can play a key role in the diagnosis of PVI. While ultrasound evaluation may detect para-uterine varices or gonadal vein reflux, we have found that magnetic resonance imaging/venography provides superior ability to detect: retrograde gonadal vein flow, para-uterine and labial varicosities, and venous anomalies that may affect catheterisation and treatment planning. Specialised techniques such as time-of-flight imaging and multiphase post-contrast imaging are critical to the detection of retrograde gonadal flow or early and dense venous enhancement. Exact size criteria of the adnexal varicosities are controversial whether ultrasound, computed tomography or MRI is concerned due to the fact that these examinations are performed in the supine position. Laparoscopy is frequently performed on patients undergoing an evaluation for chronic pelvic pain and prominent varices may be seen without other pathology, raising the concern for pelvic congestion syndrome as a diagnosis.

Results

Various treatment options have shown promise in the treatment of symptoms of PVI, however these are limited by success rates, associated morbidity, or patient tolerance. A randomised controlled trial comparing medroxyprogresterone acetate vs. goserelin acetate demonstrated that the latter is more effective; however medications suppressing ovulation can often not be tolerated longer than six months and the authors concluded that this is unlikely to yield long-term effectiveness. Surgical hysterectomy with bilateral oophorectomy was reported in an observational study to improve symptoms, however surgery has been associated with recurrence and residual pain rates of 20 and 30%.

After Edwards, et al reported their initial success with transcatheter gondal vein embolization using metallic coils, multiple case series were published. These have demonstrated technical success rates of greater than 95% and significant relief of symptoms in 68–100% of patients with follow-up ranging from 1–48 months. Embolic materials have included coils, sclerosants, glue and vascular plugs. One randomised controlled trial compared embolization to hysterectomy with unilateral or bilateral oophorectomy and the results showed that embolization provided more durable symptom relief at 12 months.

Materials and techniques

Embolization may be performed from a transjugular or transfemoral approach depending on operator comfort. At our institution, selective gonadal venography is performed with the patient in 15° reverse trendelenburg position to emulate an upright position. After confirming venous incompetence, a balloon occlusion catheter is advanced into the gonadal vein. Venography is performed to identify the often multiple gonadal vein tributaries and pelvic collaterals. Lack of embolization of these tributaries can lead to clinical failure or recurrence. The volume of sclerosant for injection can be estimated from this venogram. We typically utilise foamed sodium tetradecyl sulphate 3% for embolization followed by metallic coils to within 3cm of the gonadal vein confluence with the renal vein/inferior vena cava. Various embolic agents have been described in the literature. However, the principle of venous tributary occlusion combined with main gonadal vein embolization is critical to the procedure’s success. We perform internal iliac venography to assess for pudendal venous incompetence, but often do not treat pelvic venous disease in the same session unless gross incompetence is seen. This is to avoid a difficult clinical post-embolization course.

Future direction

Despite the published clinical success and low morbidity of gonadal vein embolization in the treatment of PVI, there are numerous insurance coverage determination policies arguing against reimbursement for embolization. Future prospective clinical trials aimed at the comparative effectiveness of embolization with surgery are needed in the interventional community to demonstrate its advantages in terms of cost, morbidity, and clinical success.

 


Sandeep Bagla is an interventional radiologist with Association of Alexandria Radiologists, PC at Inova Alexandria Hospital Department of Cardiovascular and Interventional Radiology, Alexandria, USA. He has reported no disclo
sures pertaining to the article