From the CCSVI Alliance:

The current issue of the Italian Journal of Cardiology has a paper on CCSVI, noting that the collateral venous circulation found in pwMS increases venous return time, and the hemodynamic changes of CCSVI appear to be significantly correlated in people with MS. In 200 pwMS, 92% were found to have CCSVI. Please see page 77 for the English translation of the abstract. Thanks to Sandro for the link to this research! 
http://www.sicex.it/wp-content/uploads/2013/04/Giornale-italiano-di-cardiologia-pratica-on-line-A2-N02.pdf

Page 77:

RESULTS AND CONCLUSION
Of 200 patients with MS, 184 (92%) were diagnosed with CCSVI while 16 patients (8%) did
not respond to at least 2 Zamboni criteria, resulting in a negative diagnosis of CCSVI.
Among 38 patients studied with selective preoperative venography and positive to CCSVI, all
had venous anomalies of the internal jugular veins and 19 patients (50%) had venous anomalies of the azygos vein.
After our research we can outline the following conclusions:
1) the ECD-TCCS examination is an indispensable tool for the diagnosis of CCSVI for patients
with S.M.
However, the ECD-TCCS examination needs a new type of cultural approach and requires
an extended period for learning. Therefore it is of no surprise how the results of similar studies can present significant differences.
2) the ECD-TCCS examination is similar to selective phlebography (100% of patients) in
terms of diagnosis of CCSVI, while presenting significant margins of error when detecting
concerned vessels.
ECD-TCCS examination should therefore be entrusted with the diagnosis of CCSVI without
further specifying the nature of venous anomalies and the vessels concerned.
On the other hand, a 100% sensitivity of the ECD-TCCS examination with respect to selective phlebography in the diagnosis of CCSVI indicates how the ultrasound examination
is extremely reliable when diagnosing CCSVI.
3) In addition, a proportion of about 92% of positively diagnosed CCSVI patients with SM
shows that CCSVI is the most important risk factor or contributor of SM.