Pelvic congestion syndrome

Authors

  • Mohamed Waseem Osman MBChB,

    Specialty Registrar, Corresponding author
    • Obstetrics and Gynaecology, Queen's Medical Centre Campus, Nottingham University Hospital, Nottingham NG7 2UH, UK
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  • Ilias Nikolopoulos MBBS MRCOG,

    Specialty Registrar
    1. Obstetrics and Gynaecology, Queen's Medical Centre Campus, Nottingham University Hospital, Nottingham NG7 2UH, UK
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  • Kannamannadiar Jayaprakasan MD MRCOG MBChB PhD,

    Consultant Gynaecologist, Subspecialist and Honorary Associate Professor in Reproductive Medicine and Surgery
    1. University of Nottingham, Nottingham, UK
    2. Royal Derby Hospital, Derby, UK
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  • Nicholas Raine-Fenning MBChB, PhD

    Reader, Director of Research / Senior Consultant
    1. Reproductive Medicine and Surgery, Division of Obstetrics and Gynaecology, School of Clinical Sciences, University of Nottingham, Nottingham NG7 2UH, UK
    2. Nottingham University Research and Treatment Unit in Reproduction (NURTURE), Nottingham NG7 2UH, UK
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Correspondence: Mohamed Waseem Osman. Email: drmwosman@yahoo.com

Abstract

Key content

  • Pelvic congestion syndrome is a poorly understood condition that forms part of chronic pelvic pain syndrome – this makes up 10–40% of gynaecological outpatient department referrals.
  • Pelvic congestion syndrome is thought to affect 3.8% of women of childbearing age yet the clinicians evaluating these patients are usually unaware of the condition and a significant number of trainees are not up to date with the current diagnostic and management options.

Learning objectives

  • To learn about the pathophysiology and the risk factors.
  • To learn to recognise the condition.
  • To be able to discuss various management options and choose a definitive mode of treatment tailored to individual need.

Ethical issues

  • Are we doing justice to patients if we as clinicians are not actually aware of this common and significant condition?
  • Due to current gynaecological investigations not being able to diagnose this condition and general unawareness of the current available diagnostic tests, should we not be more aware of all the investigative modalities and the most appropriate ones for our patients so that a more definitive diagnosis can be made?

Introduction

Chronic pelvic pain is a common gynaecological complaint and may account for as many as 10–40% of all gynaecology visits.[1] There are many potential causes of chronic pelvic pain but in a significant proportion of cases there is no identifiable pathology or finding that may or may not account for the discomfort described. Pelvic congestion syndrome (PCS) is a condition of pelvic varicosities in women with unexplained pelvic pain where it has been suggested as a cause of the chronic pelvic pain. However, there is a great deal of debate as to its definition and associated clinical features.

Background

PCS was first described by Richet in 1857 and shortly afterwards by Aran in 1858.[1] It was not until the mid-1930s, however, that an association between congestion and pelvic pain was suggested by Cotte[1, 2] in women with ovarian varicosities. This relationship was subsequently confirmed by Taylor et al.[3] in 1949 and then Allen et al.[4] in 1955. Although PCS is well described in the literature, its existence as a clinical entity remains controversial as there is no reference standard and therefore valid diagnostic tests.[5] In addition, many women found to have dilated pelvic veins at laparoscopy or during ultrasound examination are asymptomatic and most women with chronic pelvic pain do not have prominent venous vasculature.[5] The prevalence is difficult to define given this confusion but PCS is thought to affect 3.8% of women of childbearing age.[6] PCS is less common than a varicocele, which is the corresponding entity in men, although this obviously reflects the ease of diagnosis rather than the clinical sequelae. Modern imaging techniques are more sensitive and more readily available and so prevalence may increase. Less radical management options are also available and appear to be promising in terms of symptom control.

Aetiology

The aetiology of PCS is poorly understood but is thought to be multifactorial. Three promising theories for the pathophysiology of PCS have been accepted by the authors and are elaborated on further.

Ovarian varicoceles

The cause of ovarian varicoceles involves both mechanical and hormonal factors.[7] Absence of ovarian vein valves is an important factor in PCS development.[8] Venous valves may be absent in the cranial portion of the ovarian vein in up to 15% of the cases on the left side and in up to 6% on the right side.[9] While the combination of ovarian vein reflux and PCS is diagnosed most frequently in multiparous women,[10] congenital absence of venous valves, leading to retrograde ovarian vein flow and primary venous reflux may explain the development of PCS in nulliparous women. It has been shown that ovarian varices are symptomatic in only 59% of patients.[11] This supports earlier suggestions that pelvic congestion syndrome is due to a combination of factors.[3] The presence of ovarian vein reflux alone does not lead to the diagnosis of PCS,[10] however, venous reflux in the ovarian veins of patients with chronic pelvic pain with no other identifiable cause of organic disease makes the diagnosis of PCS more likely.

Pregnancy and hormonal factors

Pregnancy is believed to be one of the major risk factors for PCS. During pregnancy, ovarian vein flow may increase up to 60 times.[12] This increase in blood flow causes ovarian vein dilatation[11] and may result in venous valve incompetence.[11, 13] The relaxant effect of progesterone on the pelvic veins and the pressure effect of the gravid uterus may further increase the engorgement. The retrograde flow from the ovarian vein into the internal iliac vein is more common on the left than the right because the left ovarian vein drains directly into the left renal vein whereas the right ovarian vein drains at a sharp angle into the inferior vena cava. The fact that PCS only affects premenopausal women suggests a strong correlation between PCS and ovarian activity.[6]

Nutcracker syndrome

Nutcracker syndrome occurs when the left renal vein is compressed between the superior mesenteric artery and the aorta. A depiction was given by Chait et al.[14] describing the aorta as two arms of a ‘nutcracker’ that can compress the left renal vein. This dramatic description prompted a Belgian physician to name this phenomenon the nutcracker syndrome.[15] The syndrome, more frequently associated with a varicocele in men, may manifest as a dragging sensation in the scrotum with a dull aching pain and abnormalities in semen parameters and haematuria, abnormal menstruation and left flank pain in women. The testicles and ovaries share a very similar venous drainage pattern by means of the left gonadal vein in the male and the left ovarian vein in the female draining into the left renal vein and the right gonadal vein and right ovarian vein draining directly into the inferior vena cava. This similarity in these venous drainage systems would explain the presentation of ovarian varicoceles in women and a corresponding entity in males, testicular varicoceles.[3]

Prevalence

The only reported study in the English literature evaluating the incidence of PCS reported a prevalence of 9.9% in women in the age range of 18–76 years where the median age of the study group was 43 years.[16] The majority of these women (59%) were symptomatic.[16] This may reflect the true prevalence of PCS, however, one has to bear in mind that there is controversy with regard to the diagnosis of PCS as some clinicians are unwilling to acknowledge the existence of PCS as a clinical entity.

The pain pathway

In PCS the venous engorgement results in stretching of the intima of the ovarian vein. This leads to distortion of the endothelial and smooth muscle cells within the vessel with the resultant release of vasoactive substances, including substance P which is a neuropeptide and also neurokinins A and B which are involved in inflammatory processes and pain.[17]

Clinical features and presentation

There are a wide variety of symptoms that PCS may present with and this may be a reason why PCS is not considered often enough as a differential diagnosis of chronic pelvic pain (CPP). PCS commonly presents in premenopausal multiparous women.[7, 17] The most common feature is pain, which may be unilateral or bilateral, can be acute and severe or chronic and dull.[17] Patients present with pelvic pain without evidence of inflammatory disease.[7] The pain is worse during the premenstrual period and pregnancy, and is exacerbated by fatigue and standing.[7] Pain can also increase after intercourse and may lead to patient anxiety and relationship difficulties.[7] The dyspareunia due to endometriosis is usually with deep penetration during intercourse, whereas the dyspareunia due to PCS is usually worsened by intercourse resulting in a throbbing ache afterwards.

Symptoms mimicking urinary tract infection are not unusual; this is due to varicosities in the bladder trigone region.

This organic disease can further manifest with psychological symptoms such as depression and anxiety. This is partly because of the protracted time taken in making a diagnosis as PCS is often at the latter end of the differential diagnoses. PCS remains an under-diagnosed cause of chronic pelvic pain.[7] It is thought that psychological stress could be worsened by the release of substances such as substance P and neurokinins A and B as part of the pathophysiology of PCS.[17]

Two studies have shown a 41–56% association of PCS with polycystic changes in the ovaries, however, the significance of these changes remains unclear.[18, 19]

Investigations

Radiological imaging is essential in the assessment of PCS and is frequently used to confirm the clinical suspicion of this condition. Non-invasive modalities are recommended as a first-line investigation, however, the gold standard remains selective venography.[7]

Non-invasive imaging

Pelvic ultrasound

Pelvic ultrasound has been found to be a simple yet valuable first-line investigating tool for PCS as it can easily eliminate the possibility of any other major abdomino-pelvic masses that may present with PCS-like symptoms.[7] To date there have been no randomised controlled trials of distinguishing the efficacy of transvaginal or transabdominal ultrasound versus that of ovarian vein venography.[7] It has been suggested that assessing the patient in the standing position may reproduce the venous dilation but as this is not the easiest technique it is often preferable to ask the patient to perform the Valsalva manoeuvre.[20] The ultrasound images in Figures 1 and 2 demonstrate a normal uterus, myometrium and subendometrium, whereas Figures 3, 4 and 5 reveal distended and dilated venous plexuses, iliac vessels and arcuate veins.

Figure 1.

Sagittal section: anteverted uterus with normal power Doppler of the myometrium and subendometrium

Figure 2.

Sagittal section: normal anteverted uterus

Figure 3.

Power Doppler showing distended iliac vessels

Figure 4.

Transverse view: demonstrating dilated and distended parametrial plexus – note the distention is more pronounced on the left side

Figure 5.

Longitudinal view: Power Doppler of the uterus and the pronounced distension of the arcuate veins posteriorly

[Source: All images are sourced from Mr Raine-Fenning's archives with his permission.]

The most common ultrasound criteria used for evaluating PCS in the literature are:[18, 21, 22]

  • Tortuous pelvic veins with a diameter of greater than 6 mm. Mean diameter in PCS ˜8 mm.
  • Slow blood flow < 3 cm/second or reversed caudal flow in the left ovarian vein demonstrated by Doppler waveforms.
  • Dilated arcuate veins in the myometrium that communicate between the bilateral pelvic varicose veins.
  • Polycystic changes within the ovaries. Features ranged from the typical polycystic ovaries appearance to the presence of clusters of four to six cysts of 5–15 mm in diameter in bilaterally enlarged ovaries. Women with polycystic changes of their ovaries secondary to PCS were not hirsute or amenorrheic.

Despite these suggestions, there is no consensus on the diagnostic criteria for PCS. Different authors use one or more of the criteria outlined above. Furthermore, the variability in these measures has not been tested between users or across one or more menstrual cycles. One has to question their reproducibility and therefore further studies are required.

Computed tomography and magnetic resonance imaging

Both computed tomography and magnetic resonance imaging demonstrate tortuous, dilated and enhancing tubular structures near the ovaries and uterus due to the PCS varices.[7] These imaging modalities have their limitation due to the need for the patient to be imaged in the supine position. This may result in less severe cases being missed as the venous distension may reduce and not be demonstrated.[17]

Magnetic resonance phase-contrast velocity mapping was demonstrated to be a useful tool in diagnosing pelvic congestion syndrome compared with venography.[23] A prospective study from 2011 showed that phase-contrast velocity mapping diagnosed eight cases of PCS correctly, compared with venography which correctly diagnosed seven and missed one case where the patient was actually symptomatic and had an abnormal magnetic resonance phase contrast velocity mapping study.[23] If the facilities and expertise are available, magnetic resonance phase-contrast velocity mapping may be preferred to venography as the former is non-invasive.[23]

Invasive imaging

Venography

Venography remains the definitive imaging modality used to evaluate patients with PCS.[7] The presence of one or more of the following venographic appearances is said to be suggestive of PCS:[22]

  • ovarian vein diameter >10 mm
  • uterine venous engorgement
  • congestion of the ovarian plexus
  • filling of the pelvic veins across the midline and/or filling of the vulvovaginal thigh varicosities.

While venography can be performed through the jugular or femoral vein, the former approach is suggested as the preferred option if embolisation is to be performed at the same time.[17] The reproducibility of venography has also not been adequately tested. These procedures are invasive, and may, however, albeit infrequently, result in complications such as contrast extravasation, venepuncture site haematoma and vessel injury.

A retrospective study evaluating time resolved imaging of contrast kinetics (TRICKS) magnetic resonance venography (MRV) revealed promising results in diagnosing ovarian vein reflux, vein dilation with obvious advantages over transfemoral venography, ultrasonography, computed tomography and magnetic resonance imaging, such as the lack of ionising radiation or intervention and improved 3D volume images dynamically over multiple phases.[24] The study had limitations and inherent weaknesses that were recognised by the authors but they concluded that TRICKS MRV accurately and dynamically demonstrated ovarian vein reflux in patients with PCS but requires quiet respiration.

Laparoscopy

Diagnostic laparoscopy may enable the surgeon to visualise the engorgement directly, but may provide false negative results due to the supine positioning and insufflation of pressurised carbon dioxide into the peritoneum, resulting in possible venous decompression.[21] The data are limited on diagnostic laparoscopy and evaluating PCS.

Management

A multidisciplinary team approach should be implemented. The disciplines involved should include: gynaecology, gastroenterology, the pain team, psychology, interventional radiology and physiotherapy. The treatment options can be categorised into medical, surgical and endovascular interventions.

Medical treatment

Non-steroidal anti-inflammatory drugs are an acceptable first-line management. They offer a short-term solution and may provide some relief while the patient awaits further investigations or a more permanent treatment.

Ovarian suppression has been postulated to be beneficial for the treatment of women suffering from PCS. It has been suggested that estrogen may have some venodilatory effects and therefore hypo-estrogenic states can result in symptom resolution.[17] However, the studies are of small sizes therefore firm conclusions cannot be drawn from just these studies in isolation.

Medroxyprogesterone acetate (MPA) has been shown to be beneficial both subjectively in terms of pain perception and objectively by assessing pelvic congestion using venography. In a study, 30 mg MPA for 6 months was used in 22 women to suppress the ovarian function.[21] In 17 out of 22 women a reduction in pelvic congestion was demonstrated by venography and in 16 women this was associated with induction of amenorrhoea, which suggests that effective ovarian suppression is an important component of successful treatment. In the 17 women who showed a reduction in venogram score, the median change in pain score was 75% compared with only 29% in the five women with no change in venogram score (P < 0.01).[21] In a randomised controlled trial,[25] treatment with MPA was associated with a statistically significant improvement of visual analogue pain scores compared with placebo, with the pain score reducing by 58% in the MPA group compared with 28% in the placebo group (P < 0.01).

Gonadotrophin-releasing hormone (GnRH) agonists have also been suggested for the treatment of PCS. In a prospective randomised controlled trial,[26] 47 patients diagnosed with PCS were treated with either goserelin (GnRH agonist) without add-back hormone replacement therapy (HRT) or MPA for 6 months. Both treatments showed subjective and objective improvement of PCS as well as reduction in anxiety levels and improvement in sexual satisfaction. However, at a 12-month follow-up after completion of the treatment, a statistical comparison of these agents confirmed a better outcome for goserelin.[26] The main side effects of progestins were weight gain and bloating, whereas the use of GnRH analogues was associated with menopausal symptoms.

Recently, venoactive drugs like micronised purified flavonoid fraction (Daflon 500 mg) have been investigated for the treatment of PCS.[27] They provide a protective and tonic effect on the venous and capillary wall, resulting in an increase in venous tone, improvement in lymphatic drainage and a reduction in capillary hyperpermeability and therefore ameliorate venous stasis.[27] Simsek et al.[27] performed a cross-design study where 10 women with PCS received Daflon 500 mg twice daily for 6 months and another 10 received a vitamin placebo first, and then crossover of treatment occurred for another 6 months. This study showed a statistically significant improvement in pelvic pain scores in both groups without any side effects.[27]

The above studies have shown that medical management of PCS can prove to be beneficial for women, however, there is insufficient evidence regarding their long-term effectiveness in controlling their debilitating symptoms. Specifically, GnRH agonist may be used for 6 months (without add-back hormone replacement therapy [HRT]) or up to 2 years with add-back HRT to reduce the risk of osteoporosis. Therefore, the use of progestins should be further evaluated as a long-term treatment option for PCS, taking into account that bone density is slightly reduced during its usage. The reduction in bone density appears to be reversible and is probably of minor clinical significance in women in their second and third decade, however, there are some concerns about the reversibility of bone mineral density reduction in women in their early and later reproductive years.

Surgical management

Historically, gynaecological treatment for PCS focused on uterine malposition (retroversion or retroflexion), as it was thought that it caused venous kinking, obstruction and stasis. Therefore, surgical ventrosuspension was the treatment of choice for women with retroverted uterus. Nowadays this procedure has been abandoned as it has been shown to have little benefit in managing the symptoms of women suffering with PCS.[28]

In 1984, Rundqvist et al.[29] proposed extraperitoneal resection of the left ovarian vein as an effective treatment for PCS achieving a 73% cure rate and a 78% overall symptomatic improvement. Out of 15 patients, 8 were completely cured and 3 were significantly improved whereas 4 women showed no improvement with a mean period of follow-up of 5.6 years.[29] More recently, laparoscopic bilateral transperitoneal ligation of ovarian veins has been proposed with reports of complete remission of pain and absence of pelvic varicosities for 12 months after this treatment modality.[30] However, as both studies referred to above had a very small sample size, no firm conclusions can be drawn regarding the effectiveness of these surgical techniques.

A non-randomised single-centre study demonstrated that hysterectomy and bilateral oophorectomy with hormone replacement therapy was an effective treatment for PCS chronic pelvic pain as 35 of 36 women had complete resolution of their pelvic pain post-surgery.[31] In a randomised controlled trial by Chung et al. in 2003,[31] 106 women with pelvic congestion syndrome who failed to show any improvement with MPA for 4–6 months were randomly assigned into three treatment groups: ovarian vein embolisation; hysterectomy and bilateral salpingo-oophorectomy and HRT; and hysterectomy and unilateral salpingo-oophrectomy of the ovary with evidence of varices. The study showed statistically significant reduction in pain scores after embolotherapy and hysterectomy with bilateral salpingo-oophorectomy but not after unilateral oophorectomy. Unfortunately, there are no studies that compare the effectiveness of surgical management in women with pelvic congestion syndrome against medical management with GNRH agonist.

Endovascular treatment

Transcatheter embolotherapy as a treatment for PCS was initially described in 1993.[31] Ovarian and pelvic veins can be approached from a jugular or femoral vein and the embolisation can be performed with different agents such as steel coils, sclerosants (purified pork skin gelatine, sodium morrhuate) or glue. There are no published randomised controlled trials comparing the different embolisation techniques, however, a few prospective studies have been identified that demonstrate the various embolisation techniques and assess their effectiveness on pelvic pain.[32-35] The results of these studies show significant improvement in pain ranging from 58% to 83%. The method of assessment of post-procedure symptoms was different in each study, varying from clinical assessments to questionnaires and pain-score scales. Therefore, no firm conclusions could be drawn from them.

Overall endovascular management has been demonstrated to be superior to the surgical option of hysterectomy and bilateral oophorectomy.[36] For symptom amelioration, it is unclear whether embolisation should be performed only on the refluxing veins, on both ovarian veins, or on both the ovarian and internal iliac veins. It is therefore apparent that there is a need for well-designed randomised controlled trials to consistently assess the effectiveness of each technique.

The main complications that have been reported with transcatheter embolisation include coil migration that can be retrieved without any sequelae, ovarian vein perforation and venupucture-site haematomas that can cause pain, and both may be treated symptomatically.[37] No significant changes were noted in hormone levels or menstrual cycle after embolotherapy and successful pregnancies following treatment have also been reported.[34, 37]

Psychotherapy

Psychotherapy in the form of cognitive behavioural therapy (CBT) has also been demonstrated to be beneficial when combined with medical or surgical management in all forms of chronic pain including PCS. CBT can ameliorate negative psychological propensities, such as fear, and enable patients to develop coping strategies. A randomised controlled trial comparing MPA alone, MPA and psychotherapy, placebo alone and placebo and psychotherapy for 4 months showed that the combined effect of MPA and psychotherapy for the treatment of PCS was superior, achieving a greater than 50% reduction in pain score that lasted for 9 months after the completion of treatment.[25]

Conclusion

PCS remains a controversial clinical entity. It is an unfamiliar condition to many clinicians and is seldom considered in the differential diagnosis of the causes of chronic pelvic pain in women. This probably reflects the lack of consistent diagnostic criteria and acceptable, non-invasive tests. There are several hypotheses regarding the aetiology of PCS, which include ovarian varicoceles, hormonal factors and structural factors including pregnancy and the nutcracker syndrome. The presence of the above mentioned factors does not infer that a woman will have dilated pelvic vessels or the associated symptoms of PCS. New diagnostic criteria need to be established and their reproducibility and validity tested in accordance with guidelines for any test accuracy study.

The management of PCS is also uncertain. Various medical and surgical options are available but a biopsychosocial approach is paramount. A medical approach should be offered initially, reserving surgery for resistant cases and those intolerant of side effects. Endovascular management with percutaneous embolisation of the ovarian/internal iliac vein varicosities may prove to be the preferred treatment option as it is minimally invasive and is associated with fewer complications than surgical management. The evidence base for the treatment of PCS is poor, however, and well-designed randomised controlled trials are required. These require a revision of the diagnostic criteria as outlined above but also an awareness of the condition. Without these developments PCS is likely to remain an enigma and women may be denied optimal diagnosis and treatment.

Disclosure of interests

None declared.

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