Wednesday, 4 January 2012

Research: Imaging CCSVI?

Dolic K et al. Intra- and Extraluminal Structural and Functional Venous Anomalies in Multiple Sclerosis, as Evidenced by 2 Noninvasive Imaging Techniques.AJNR Am J Neuroradiol. 2011 Dec [Epub]

Chronic cerebrospinal venous insufficiency (CCSVI) is a vascular condition characterized by anomalies of the main extracranial cerebrospinal venous routes that interfere with normal venous outflow. Research into CCSVI will determine its sensitivity and specificity for a diagnosis of MS, its prevalence in MS patients, and its clinical, MRI, and genetic correlates. Our aim was to investigate the prevalence and number of intra- and extraluminal structural and functional extracranial venous abnormalities by usin Doppler sonography and magnetic resonance venography (MRV) in patients with MS and Healthy controls (HC)

MATERIALS AND METHODS: One hundred fifty patients with MS, 104 (69.3%) with RR and 46 (30.7%) with a progressive MS course, and 63 age- and sex-matched controls (HC) were scanned with 3T Magnetic resonance imaging. All subjects underwent Doppler sonography examination for intra- and extraluminal (inside and outside the lumen/space) structural and functional abnormalities of the Internal JugularVeins. Absent/pinpoint IJV flow morphology on magnetic resonance venography was considered an abnormal finding. Prominence of collateral extracranial veins was assessed with MRV.

RESULTS: Patients with MS had a significantly higher number of functional (P < .0001), total (P = .001), and intraluminal (P = .005) structural internal JugularVein Doppler sonography abnormalities than healthy controls. There was a trend for more patients with MS with extraluminal vein DS abnormalities (P = .023). No significant differences were found on the magnetic resonance venography, IJV flow morphology scale between patients with MS and halthy controls. Patients with progressive MS showed more extraluminal IJV DS abnormalities (P = .01) and more magnetic resonance venography flow abnormalities (P = 0.01) than patients with nonprogressive MS. There was a trend (p=0.016) for a higher number of collateral veins in patients with MS than in healty controls.

CONCLUSIONS: Doppler sonography is more sensitive than MRV in detecting intraluminal structural and functional venous abnormalities in patients with MS compared with HCs, whereas MRV is more sensitive in showing collaterals.

Ertl-Wagner B et al. Non-specific alterations of craniocervical venous drainage in multiple sclerosis revealed by cardiac-gated phase-contrast MRI.Mult Scler. 2011. Dec [Epub]

Objective: There is an on-going controversy about venous drainage abnormalities in multiple sclerosis (MS). We applied cardiac-gated phase-contrast and venographic magnetic resonance (MR) techniques to compare venous drainage patterns in patients with MS, healthy controls, and subjects with migraine.

Methods: A total of 27 patients with MS (21 female, age 12-59 years, mean disease duration 8.4 ± 8.5 years) and 27 age- and gender-matched healthy controls (21 female, age 12-60 years) were investigated with velocity-encoded cine-phase contrast MR sequences and a 2D time-of-flight MRV of the cervicocranial region on a 3-T MRI. The data were compared with 26 patients with chronic migraine headaches (19 female, age 17-62 years), previously investigated with the same protocol. The degree of primary and secondary venous outflow in relation to the total cerebral blood flow (tCBF) was compared both quantitatively and qualitatively.

Results: Secondary venous outflow was significantly increased in patients with MS compared with healthy controls, both qualitatively (p < 0.001) and quantitatively (p < 0.013). The observed changes were independent of age and disease duration. Very similar alterations of venous drainage were detectable with the same approach in patients with migraine, without significant differences between MS and migraine patients (p = 0.65).

Conclusion: Our MRI-based study suggests that patients with MS have alterations of cerebral venous drainage similar to subjects with chronic migraine. These non-disease-specific changes seem to a secondary phenomenon rather than being of primary pathogenic importance.

So we can expect to see alot of publications around CCSVI as responses to the desire for research on this subject, but rather than clarity there is increasing ambiguity. One thing is clear is that whilst there may be vascular abnormalities in MSers as assessed by ultra sonic analysis, this does not occur in all MSers and also occurrs in healthy controls. Addition of magnetic resonance venoscopy does not really add to the CCSVI validity and serves to confuse the matter further, where again changes can be seen but again are not specific to MS. So what is the ultrasound really detecting?