Chronic cerebrospinal venous insufficiency is not more prevalent in patients with mild multiple sclerosis: a sonographer-blinded, case-control ultrasound study

A prolonged antibiotic protocol to treat persistent Chlamydophila pneumoniae infection improves the extracranial venous circulation in multiple sclerosis

Objective Chronic cerebrospinal venous insufficiency (CCSVI) is a condition associated with multiple sclerosis (MS). One mechanism that has been proposed is that the venous obstructions found in MS are due to a chronic persistent venulitis caused by the intra-cellular bacterial parasite, Chlamydophila pneumoniae (Cpn). The objective of the current study is to determine the effect of a combined antibiotic protocol (CAP) on the venous flow in MS patients as measured by a quantitative duplex ultrasound examination (QDUS). Method A non-randomised before-after cohort study was conducted to investigate differences in blood flow volumes pre and 6-months post antibiotic treatment for Cpn infection. Flow volume data were measured by QDUS across affected and unaffected sides from multiple veins segments, including internal jugular vein (IJV) segments J2 and J3, and vertebral vein (VV), as well as global arterial blood flow (GABF). Results 91 patients were included in the study. 64 (70%) were found to have positive Cpn serology. There was a statistically significant post-treatment difference seen for the affected side of Cpn infected patients (mean difference = 56 mL/min, p = 0.02). There was a non-significant increase seen for the affected side of uninfected patients (mean difference = 23 mL/min, p = 0.2). The difference in these effects (34 mL/min) was not statistically significant ( p = 0.3). The mean flow rate decreased in the unaffected side for both infected (-27 mL/min, p = 0.5) and uninfected patients (-69 mL/min, p = 0.01). There was a statistically significant post-treatment increase in GABF for the infected patients (mean difference = 90 mL/min, p = 0.02) and a difference of 76 mL/min for non-infected patients ( p = 0.01). Conclusion A CAP appears to improve the extra-cranial circulation in patients diagnosed with MS. This effect is statistically significant in patients with positive Cpn serology, although patients with negative Cpn serology also show some benefit, betraying a lack of specificity of this effect.

Original Research: Feasibility and safety of two surgical techniques for the development of an animal model of jugular vein occlusion

To date, no studies have explored the effect of abnormal cerebral venous circulation on brain disorders, whereas many studies have investigated neurodegenerative brain anomalies associated with arterial diseases. The aim of our study was to demonstrate the feasibility of different surgical techniques to induce venous obstruction of cerebral brain drainage. Six C57/black mice underwent bilateral occlusion of the external jugular vein (group EJV), six underwent bilateral occlusion of the internal jugular vein (group IJV), and six underwent bilateral occlusion of both the EJV and the IJV (group EJV/IJV). Within each group, the interruption of blood flow was obtained via monopolar electro-coagulation (ME) in three mice and via surgical ligation (SL) in the remaining three mice. A "sham group" of two mice was used as the control. High-frequency ultrasound (HFUS) was used to detect the absence of blood flow in the examined vessel. The ME procedure led to successful results in two of nine (22%) mice, one in the EJV group, one in the EJV/IJV group, and zero in the IJV group, and 4 of 18 (22%) mice when considering individual veins (i.e., total number of EJVs and IJVs occluded). The SL procedure was successful in two of three (67%) mice in the EJV group, in three of three (100%) mice in the IJV and in three of four (75%) mice in the EJV/IJV group. Therefore, the overall success rate was 8/10 (80%) when considering mice, and 20/26 (77%) when considering individual veins. The monopolar electro-coagulation method exhibited a high mortality due to cardiorespiratory arrest, while the results of the bilateral surgical ligation of EJVs and IJVs show that it is technically feasible and safe.

Lack of correlation between extracranial venous abnormalities and multiple sclerosis: a quantitative MRI study

OBJECTIVE:

We aimed to evaluate the presence of venous stenosis and blood flow abnormalities in the neck vessels of patients with multiple sclerosis (MS), in respect to a group of age- and sex-matched healthy controls (HC), and their possible relations with clinical variables using a semi-automated quantitative MRI method.

METHODS:

45 patients with relapsing remitting MS and 40 HC were enrolled in this study. Flow rates and cross-sectional areas of arterial and venous neck vessels were assessed by phase-contrast MRI at two different neck levels (C2-C3 and C6-C7), and differences between groups were evaluated with an unpaired t-test. Correlation between blood flow variables and clinical parameters was analyzed with Spearman's test.

RESULTS:

A significant internal jugular vein (IJV) stenosis was found in 23/45 (51.1%) patients with MS and 18/40 (45.0%) HC. No differences were observed between patients with MS and HC for any of the flow measures obtained. No correlations were found between MRI measures and any of the tested clinical variables.

CONCLUSION:

No differences in the IJV area emerged at quantitative MRI evaluation, suggesting that stenosis of the extracranial veins is unrelated to MS. Furthermore, no flow differences in the neck vessels were found between patients with MS and HC in any of the tested flow measures, with no correlation with clinical variables. Our results confirm that the hypothesis of the presence of extracranial venous abnormalities in MS, both in terms of stenosis or flow measures, is not suitable.

ADVANCES IN KNOWLEDGE:

Neck venous drainage abnormalities have been claimed to be associated with MS. Conversely, our quantitative MRI analysis seems to exclude that extracranial venous alterations are related to the disease.

Variability in the Cross-Sectional Area and Narrowing of the Internal Jugular Vein in Patients Without Multiple Sclerosis

OBJECTIVE

Chronic cerebrospinal vascular insufficiency is a proposed condition of intraluminal stenosis of the internal jugular vein (IJV) that impedes venous flow from the brain. Calculations of IJV stenosis are vague and described in veins with at least a 50% reduction in IJV caliber at a specific level. The purpose of this study was to assess normal changes in anatomic caliber of the course of the IJV in a generalized population.

MATERIALS AND METHODS

Images from 500 consecutive contrast-enhanced neck CT studies performed in January-July 2011 were reviewed. Cross-sectional areas of the IJV were calculated at the jugular foramen, C1-C7 levels, and jugular angles bilaterally. Patients were excluded if they had severely motion-limited studies; limited clinical data; a history of multiple sclerosis, neck mass, or neck dissection; or known IJV occlusion. Normalized IJV cross-sectional areas at each level were compared with an averaged normalized cross-sectional area from all patients at each level.

RESULTS

Greater than 50% narrowing compared with a normalized average was found in 133 of 363 patients (36.6%) and was seen at all IJV levels. In 36.1% of patients this narrowing occurred at the C1 level. Most of the areas of narrowing greater than 50% occurred above the C4 level.

CONCLUSION

The IJV has marked variability in its course in the neck. Areas of narrowing greater than 50% occur most commonly in the upper cervical and skull base regions. Given the normal anatomic variations in IJV caliber, caution should be used when making the diagnosis of and treating IJV stenosis.

Autonomic Dysregulation in Multiple Sclerosis

Multiple sclerosis (MS) is a chronic, progressive central neurological disease characterized by inflammation and demyelination. In patients with MS, dysregulation of the autonomic nervous system may present with various clinical symptoms including sweating abnormalities, urinary dysfunction, orthostatic dysregulation, gastrointestinal symptoms, and sexual dysfunction. These autonomic disturbances reduce the quality of life of affected patients and constitute a clinical challenge to the physician due to variability of clinical presentation and inconsistent data on diagnosis and treatment. Early diagnosis and initiation of individualized interdisciplinary and multimodal strategies is beneficial in the management of autonomic dysfunction in MS. This review summarizes the current literature on the most prevalent aspects of autonomic dysfunction in MS and provides reference to underlying pathophysiological mechanisms as well as means of diagnosis and treatment.

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.

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.

Potential involvement of the extracranial venous system in central nervous system disorders and aging

BACKGROUND

The role of the extracranial venous system in the pathology of central nervous system (CNS) disorders and aging is largely unknown. It is acknowledged that the development of the venous system is subject to many variations and that these variations do not necessarily represent pathological findings. The idea has been changing with regards to the extracranial venous system.

DISCUSSION

A range of extracranial venous abnormalities have recently been reported, which could be classified as structural/morphological, hemodynamic/functional and those determined only by the composite criteria and use of multimodal imaging. The presence of these abnormalities usually disrupts normal blood flow and is associated with the development of prominent collateral circulation. The etiology of these abnormalities may be related to embryologic developmental arrest, aging or other comorbidities. Several CNS disorders have been linked to the presence and severity of jugular venous reflux. Another composite criteria-based vascular condition named chronic cerebrospinal venous insufficiency (CCSVI) was recently introduced. CCSVI is characterized by abnormalities of the main extracranial cerebrospinal venous outflow routes that may interfere with normal venous outflow.

SUMMARY

Additional research is needed to better define the role of the extracranial venous system in relation to CNS disorders and aging. The use of endovascular treatment for the correction of these extracranial venous abnormalities should be discouraged, until potential benefit is demonstrated in properly-designed, blinded, randomized and controlled clinical trials.

Internal jugular and vertebral vein volume flow in patients with clinically isolated syndrome or mild multiple sclerosis and healthy controls: results from a prospective sonographer-blinded study

OBJECTIVES & METHODS

We evaluated internal jugular vein and vertebral vein volume flow using ultrasound, in patients with clinically isolated syndrome or mild multiple sclerosis and controls, to determine whether volume flow was different between the two groups.

RESULTS

In patients and controls, internal jugular vein volume flow increased from superior to inferior segments, consistent with recruitment from collateral veins. Internal jugular vein and vertebral vein volume flow were greater on the right in supine and sitting positions. Internal jugular vein volume flow was higher in the supine posture. Vertebral vein volume flow was higher in the sitting posture. Regression analyses of cube root transformed volume flow data, adjusted for supine/sitting, right/left and internal jugular vein/vertebral vein, revealed no significant difference in volume flow in patients compared to controls.

CONCLUSIONS

Our findings further refute the concept of venous obstruction as a causal factor in the pathogenesis of multiple sclerosis. Control volume flow data may provide useful normative reference values.

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.

Chronic cerebrospinal venous insufficiency: masked multimodal imaging assessment

BACKGROUND

Chronic cerebrospinal venous insufficiency (CCSVI) was implicated in the pathophysiology of multiple sclerosis (MS).

OBJECTIVE

We evaluated neurosonography (NS), magnetic resonance venography (MRV), and transluminal venography (TLV) in subsets of MS patients drawn from a single-center, prospective, case-control study of 206 MS and 70 non-MS volunteers.

METHODS

As previously reported, findings on high-resolution B-mode NS imaging with color and spectral Doppler of the extracranial and intracranial venous drainage consistent with CCSVI were similar among MS and non-MS volunteers (3.88% vs 7.14%; p = 0.266). Ninety-nine MS participants consented to intravascular contrast-enhanced 3D MRV to assess their major systemic and intracranial venous circulation, and 40 advanced to TLV that included pressure measurements of the superior vena cava, internal jugular, brachiocephalic, and azygous veins.

RESULTS

NS findings and MRV patterns were discrepant for 26/98 evaluable subjects, including four with abnormal findings on NS that had normal venous anatomy by MRV. In no instance were TLV pressure gradients indicative of clinically significant functional stenosis encountered. The three imaging approaches provided generally consistent data with discrepancies referable to inherent technique properties.

CONCLUSIONS

Our findings lend no support for altered venous outflow dynamics as common among MS patients, nor do they likely contribute to the disease process.

The role of noninvasive and invasive diagnostic imaging techniques for detection of extra-cranial venous system anomalies and developmental variants

The extra-cranial venous system is complex and not well studied in comparison to the peripheral venous system. A newly proposed vascular condition, named chronic cerebrospinal venous insufficiency (CCSVI), described initially in patients with multiple sclerosis (MS) has triggered intense interest in better understanding of the role of extra-cranial venous anomalies and developmental variants. So far, there is no established diagnostic imaging modality, non-invasive or invasive, that can serve as the "gold standard" for detection of these venous anomalies. However, consensus guidelines and standardized imaging protocols are emerging. Most likely, a multimodal imaging approach will ultimately be the most comprehensive means for screening, diagnostic and monitoring purposes. Further research is needed to determine the spectrum of extra-cranial venous pathology and to compare the imaging findings with pathological examinations. The ability to define and reliably detect noninvasively these anomalies is an essential step toward establishing their incidence and prevalence. The role for these anomalies in causing significant hemodynamic consequences for the intra-cranial venous drainage in MS patients and other neurologic disorders, and in aging, remains unproven.