The relationship between pelvic vein incompetence and chronic pelvic pain in women: systematic reviews of diagnosis and treatment effectiveness

BACKGROUND: Pelvic congestion syndrome (PCS) is described as chronic pelvic pain (CPP) arising from dilated and refluxing pelvic veins, although the causal relationship between pelvic vein incompetence (PVI) and CPP is not established. Non-invasive screening methods such as Doppler ultrasound and magnetic resonance venography are used before confirmation by venography. Percutaneous embolisation has become the principal treatment for PCS, with high success rates often cited.

OBJECTIVES: Our proposal aimed to systematically and critically review the definitions and diagnostic criteria of PCS, the association between PVI and CPP, the accuracy of various non-invasive imaging techniques and the effectiveness of embolisation for PVI; and to identify factors associated with successful outcome. We also wished to survey clinicians and patients to assess awareness and management of PCS and gauge the enthusiasm for further research.

DATA SOURCES: A comprehensive search strategy encompassing various terms for pelvic congestion, pain, imaging techniques and embolisation was deployed in 17 bibliographic databases, including MEDLINE, EMBASE and Web of Science. There was no restriction on study design.

METHODS: Methodological quality was assessed using appropriate tools. Online surveys were sent to clinicians and patients. The quality and heterogeneity generally precluded meta-analysis and so results were tabulated and described narratively.

RESULTS: We identified six association studies, 10 studies involving ultrasound, two studies involving magnetic resonance venography, 21 case series and one poor-quality randomised trial of embolisation. There were no consistent diagnostic criteria for PCS. We found that the associations between CPP and PVI were generally fairly similar, with three of five studies with sufficient data showing statistically significant associations (odds ratios of between 31 and 117). The prevalence of PVI ranged widely, although the majority of women with PVI had CPP. Transvaginal ultrasound with Doppler and magnetic resonance venography are both useful screening methods, although the data on accuracy are limited. Early substantial relief from pain symptoms was observed in approximately 75% of women undergoing embolisation, a figure which generally increased over time and was sustained. Reintervention rates were generally low. Transient pain was a common occurrence following foam embolisation, while there was a < 2% risk of coil migration. Confidence in the embolisation technique is reasonably high, although there is a desire to strengthen the evidence base. Even among women with CPP, fewer than half had any knowledge about PCS.

CONCLUSIONS: The data supporting the diagnosis and treatment of PCS are limited and of variable methodological quality. There is some evidence to tentatively support a causative association, but it cannot be categorically stated that PVI is the cause of CPP in women with no other pathology, as the six most pertinent drew on clinically disparate populations and defined PVI inconsistently. Embolisation appears to provide symptomatic relief in the majority of women and is safe. However, the majority of included studies of embolism were relatively small case series and only the randomised controlled trial was considered at risk of potential biases. There is scope and demand for considerable further research. The question of the association of PVI and CPP requires a well-designed and well-powered case-control study, which will also provide data to derive a diagnostic standard. An adequately powered randomised trial is essential to provide evidence on the effectiveness of embolisation, but this faces methodological challenges.

STUDY REGISTRATION: This study is registered as PROSPERO CRD42012002237 and CRD42012002238.

FUNDING: The National Institute for Health Research Health Technology Assessment programme.