Chronic cerebrospinal venous insufficiency in multiple sclerosis: A sonographer-blinded case-control study

Association between chronic cerebrospinal venous insufficiency and multiple sclerosis: a systematic review and meta-analysis

OBJECTIVES

Numerous studies have indicated that chronic cerebrospinal venous insufficiency is a potential factor in causing multiple sclerosis in recent years, but this conclusion remains unconfirmed. This meta-analysis examined the correlation between multiple sclerosis and chronic cerebrospinal venous insufficiency.

METHODS

We searched Embase and Medline (Ovid) for publications published from 1 January 2006 to 1 May 2022. The meta-analysis was performed following Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines.

RESULTS

Eligible studies (n=20) included 3069 participants from seven countries. Pooled analysis indicated that chronic cerebrospinal venous insufficiency was more frequent in patients with multiple sclerosis than in healthy controls (OR 3.36; 95% CI 1.92 to 5.85; p<0.001) with remarkable heterogeneity among studies (I2=79%). Results were more strongly correlated in subsequent sensitivity analyses, but heterogeneity was also more substantial. We removed studies that initially proposed a chronic cerebrospinal venous insufficiency team as well as studies by authors involved in or advocating endovascular therapies.

CONCLUSIONS

Chronic cerebrospinal venous insufficiency is significantly associated with multiple sclerosis and it is more prevalent in patients with multiple sclerosis than in healthy individuals, but considerable heterogeneity of results is still observed.

Evaluation of hemodynamic properties of cerebral venous drainage in patients with multiple sclerosis: a case-control study

Background

The purpose of this study was to compare patients with multiple sclerosis and healthy control subjects as regards hemodynamics of cerebral venous drainage.

Material/Methods

Between December 2012 and May 2013, 44 consecutive patients with multiple sclerosis and 44 age- and sex-matched healthy subjects underwent the B-mode, color Doppler, and duplex Doppler evaluations of the internal jugular vein (IJV) and vertebral vein. The following four parameters were investigated: IJV stenosis, reversal of postural control of the cerebral venous outflow pathways, absence of detectable blood flow in the IJVs and/or vertebral veins, and reflux in the IJVs and/or vertebral veins in the sitting or supine position.

Results

In the study group, IJV stenosis, postural control reversal of the cerebral venous outflow pathways, and absence of flow in the IJVs and/or vertebral veins were found in 3 (6.8%), 2 (4.5%), and 3 (6.8%) patients, respectively. In the control group, IJV stenosis (P=0.12), postural control reversal of the cerebral venous outflow pathways (P=0.50), and absence of flow (P=0.12) were not detected. Abnormal reflux was found neither in multiple sclerosis patients nor in healthy subjects.

Conclusions

No significant difference in the cerebral venous drainage through the IJV or vertebral vein was found between patients with multiple sclerosis and healthy subjects within any of the investigated ultrasonographic parameters.

Chronic cerebrospinal venous insufficiency is not associated with chronic venous disorders: A case-control study

OBJECTIVES

To evaluate the relationship between chronic cerebrospinal venous insufficiency (CCSVI) and the presence of a Chronic Venous Disorder (CVD).

METHOD

We included 55 subjects with CCSVI aged >18 years, and 186 controls without CCSVI. Each subject was evaluated with color Doppler sonography in accordance with Zamboni's five criteria, examined by two neurologists and interviewed with an ad-hoc designed form. The neurologists and the sonographers were mutually blinded. CVD were classified according to CEAP.

RESULTS

Mean age was 42 years (SD = 9) in cases and 43 years (10) in controls (p = ns). The odds ratios in subjects CCSVI were 0.6 (0.2-2.2) for CEAP 1, 0.9 (0.2-4.5) for CEAP 2, and 1.0 (0.6-1.9) for family history of varicose veins. The prevalence of CVD and, family history of varicose veins, was similar between cases and controls for each Zamboni criterion.

CONCLUSIONS

We found no association of CCSVI with the presence of CVD or family history of varicose veins.

Is there any relation between chronic cerebrospinal venous insufficiency and multiple sclerosis? - a critical review

Summary Though the etiology of multiple sclerosis remains unknown, the widely accepted explanation is that it has an autoimmune inflammatory background. In 2006 Paolo Zamboni renewed the somewhat forgotten vascular theory of the pathogenesis of multiple sclerosis, proposing the new entity of 'chronic cerebrospinal venous insufficiency'. As a result of this hypothesis, Zamboni suggested an endovascular treatment for multiple sclerosis involving venoplasty of the internal jugular vein and the azygos vein. Unfortunately, several teams have tried to replicate Zamboni's results without success. In this review, we present a chronological description of the results of the studies conducted by Zamboni and the later attempts to replicate his work. The main conclusion is that, taking into account results that are currently available, we should remain cautious and routine use of this treatment in patients should not be advisable.

A reliability study of colour-Doppler sonography for the diagnosis of chronic cerebrospinal venous insufficiency shows low inter-rater agreement

OBJECTIVE

Chronic cerebrospinal venous insufficiency (CCSVI) has been extremely variable, associated with multiple sclerosis in colour-Doppler sonographic studies. We aimed to evaluate inter-rater agreement in a colour-Doppler sonography venous examination.

DESIGN

Inter-rater agreement study.

SETTING

First-referral multiple sclerosis centre.

PARTICIPANTS

38 patients with multiple sclerosis and 55 age-matched (±5 years) controls.

INTERVENTION

Sonography was carried out in accordance with Zamboni's five criteria by eight sonographers with different expertise, blinded to the status of cases and controls. Each participant was evaluated by two operators.

PRIMARY AND SECONDARY OUTCOME MEASURES

Inter-rater agreement was measured through the κ statistics and the intraclass correlation coefficient.

RESULTS

The agreement was no higher than chance for criterion 2-reflux in the deep cerebral veins (κ=-0.02) and criterion 4-flow not Doppler detectable in one or both the internal jugular veins (IJVs) or vertebral veins (VVs; -0.09). It was substantially low for criterion 1-reflux in the IJVs and/or VVs (0.29), criterion 3-IJV stenosis or malformations (0.23) and criterion 5-absence of IJV diameter increase when passing from the sitting to the supine position (0.22). The κ value for CCSVI as a whole was 0.20 (95% confidence limit -0.01 to 0.42). Intraclass correlation coefficients for the measure of cross-sectional area ranged from 0.05 to 0.25. Inter-rater agreement was low for CCSVI experts (κ=0.24; -0.11 to 0.59) and non-experts (0.20; -0.33 to 0.73); neurologists (0.21; -0.06 to 0.47) and non-neurologists (0.18; -0.20 to 0.56); cases (0.19; -0.14 to 0.52) and controls (0.21; -0.08 to 0.49). Zamboni-trained neurosonographers ascertained CCSVI more frequently than the non-trained neurosonographers.

CONCLUSIONS

Agreement was unsatisfactory for the diagnosis of CCSVI as a whole, for each of its five criteria and according to the different subgroups. Standardisation of the method is urgently needed prior to its further application in studies of patients with multiple sclerosis or other neurological diseases.

Observational case-control study of the prevalence of chronic cerebrospinal venous insufficiency in multiple sclerosis: results from the CoSMo study

BACKGROUND

Chronic cerebrospinal venous insufficiency (CCSVI) has been proposed as a possible cause of multiple sclerosis (MS).

OBJECTIVES

The CoSMo study evaluated the association between CCSVI and MS.

METHODS

The primary end-point of this multicentric, case-control study was to compare the prevalence of CCSVI between patients with MS, patients with other neurodegenerative diseases (ONDs) and healthy controls (HCs). Color-coded duplex sonography was performed by a sonologist and the images were sent to one of three central sonologists for a second reading. Agreement between local and central sonologists or, in case of disagreement, the predominant judgment among the three central readers, was required for a diagnosis of CCSVI. All readings, data collection and analysis were blinded.

RESULTS

The study involved 35 MS centers across Italy and included 1874 subjects aged 18-55. 1767 (94%) were evaluable: 1165 MS patients, 226 patients with ONDs and 376 HCs. CCSVI prevalence was 3.26%, 3.10% and 2.13% for the MS, OND and HC groups, respectively. No significant difference in CCSVI prevalence was found amongst the three cohorts (MS versus HC, OR = 1.55, 95%CI = 0.72-3.36, p = 0.30; OND versus HC, OR = 1.47, 95%CI = 0.53-4.11, p = 0.46; MS versus OND, OR = 1.05, 95%CI = 0.47-2.39, p = 0.99). High negative and low positive agreement was found between the local and centralized readers.

CONCLUSIONS

CCSVI is not associated with MS.

Meta-Analysis of the Correlation Between Chronic Cerebrospinal Venous Insufficiency and Multiple Sclerosis

Purpose:

To determine whether a correlation exists between chronic cerebrospinal venous insufficiency (CCSVI) and multiple sclerosis (MS).

Materials and Methods:

A meta-analysis of the current literature was performed to evaluate the frequency of CCSVI, diagnosed by echo color Doppler criteria, in patients with MS and in normal controls.

Results:

In all, 19 studies were identified from January 2005 through February 2013; however, 3 studies were excluded due to duplicate data and 3 additional studies because 0 patients fulfilled CCSVI criteria in both MS and control groups. In order to improve homogeneity, 4 outlier studies were also removed from the analysis. Analysis of the remaining 9 studies demonstrated a significant correlation between CCSVI and MS (odds ratio 1.885, P < .0001) with no significant heterogeneity of the studies ( I2 = 18, P = .279).

Conclusions:

The meta-analysis demonstrated a correlation between CCSVI and MS. However, there was no evidence that CCSVI has a causative role in MS.

Evidence against the involvement of chronic cerebrospinal venous abnormalities in multiple sclerosis. A case-control study

Objective

Multiple sclerosis (MS) is a chronic neurodegenerative disease of the CNS. Recently a controversial vascular hypothesis for MS, termed chronic cerebrospinal venous insufficiency (CCSVI), has been advanced. The objective of this study was to evaluate the relative prevalence of the venous abnormalities that define CCSVI.

Methods

A case-control study was conducted in which 100 MS patients aged between 18–65 y meeting the revised McDonald criteria were randomly selected and stratified into one of four MS subtypes: relapsing/remitting, secondary progressive, primary progressive and benign. Control subjects (16–70 y) with no known history of MS or other neurological condition were matched with the MS cases. All cases and controls underwent ultrasound imaging of the veins of the neck plus the deep cerebral veins, and magnetic resonance imaging of the neck veins and brain. These procedures were performed on each participant on the same day.

Results

On ultrasound we found no evidence of reflux, stenosis or blockage in the internal jugular veins (IJV) or vertebral veins (VV) in any study participant. Similarly, there was no evidence of either reflux or cessation of flow in the deep cerebral veins in any subject. Flow was detected in the IJV and VV in all study participants. Amongst 199 participants there was one MS subject who fulfilled the minimum two ultrasound criteria for CCSVI. Using MRI we found no significant differences in either the intra- or extra-cranial venous flow velocity or venous architecture between cases and controls.

Conclusion

This case-control study provides compelling evidence against the involvement of CCSVI in multiple sclerosis.