Wheelchair Kamikaze offers his analysis on what the Cleveland Clinic autopsy study findings might mean ...http://www.wheelchairkamikaze.com/2011/ ... s-and.html
The unique aspect of this study is that investigators were actually able to hold and examine the veins in question, the only imaging technology utilized being the ever trusty human eye (presumably aided by some type of optical magnification).
Although quite small, limited to only 13 subjects, the study hints at some rather dramatic trends (click here). The researchers looked at the veins of 7 MS and 6 non-MS subjects, and found a variety of structural abnormalities and anatomic variations. Interestingly, vein wall stenosis (narrowing) occurred in equal numbers among the MS and non-MS samples. More prevalent in the MS veins, though, were abnormalities involving malformed valves and anomalous membranes (structures such as webs and septums that shouldn't be there) which could lead to disrupted blood flow. These types of abnormalities would be difficult to spot using noninvasive imaging methods, casting further doubt on studies reliant strictly on traditional MRV in particular, and also Doppler sonography unless the operators were well-versed in protocols specifically designed reveal such anatomic irregularities.
The findings of this study, if borne out by future, larger investigations, could shed light on the wide disparity in benefit (or, often, lack of benefit) experienced by those who have undergone CCSVI venoplasty (click here for a terrific discussion of this, written by Julie Stachowiak of about.com). Many CCSVI treatment procedures, especially those done within the first year or so after knowledge of CCSVI hit the mainstream MS population, concentrated primarily on areas of venous narrowing, which the Cleveland Clinic findings suggest are not as abnormal as first thought. Since these narrowings were seen in equal numbers among MS and non-MS subjects, they may fall within the parameters of normal anatomic variation, and have little actual significance.
The high prevalence of malformed or misplaced valves and other anatomic structures within the veins of MS patients, on the other hand, could very well prove to have considerable import. Although the goal of CCSVI treatment has in large part shifted away from simply expanding narrowed veins and moved more towards clearing malformed or otherwise broken valves, aberrant membranes would in many cases be difficult to treat using the balloon venoplasty techniques currently employed to address CCSVI. In theory, some of these treatments may have coincidentally alleviated the effects of such abnormal membranes by disrupting them and compressing them against the vein walls of treated patients. If this were the case, and these membranes eventually returned to their original form, this might explain the far too common phenomenon of restenosis experienced by patients treated for CCSVI. The failure to properly treat malformed valves and abnormal and misplaced membranes within the veins might also explain the failure of CCSVI treatment to significantly benefit many of those who have undergone treatment. This of course assumes that the MS-CCSVI link exists, which despite a growing body of anecdotal evidence, still needs to be confirmed by scientifically robust studies.
Did I over-quote? There's more where that came from.
Even before the CCSVI investigators knew they were treating the valves, they were treating the area of the valves, since that is where the narrowing was. This was true of Dr. Zamboni and Dr. Sclafani, certainly.
That these types of abnormalities would be difficult to spot with the imaging methods (doppler ultrasound, MRV, and sometimes even phlebography fails when not coupled with IVUS) is a significant point, after all the disparity seen in imaging studies.
I would definitely like to see larger future studies of this nature.
Consider this a plug too for Wheelchair Kamikaze's blog. Well worth the read.