Dear Dr. Sclafani,
I would like to ask you the following questions:
1. I’m a little concerned about the radiation dose required for the venography. I guess the angioplasty procedure is also done under X-ray, is that correct?
Could you tell how high the overall radiation (diagnosis and treatment) might approximately be – could it be compared to n-number of “usual” X-ray images or do you know about the approx. overall radiation level in the physical unit [Coulomb]?
Is there reason to be concerned about the radiation dose in conjunction with the diagnostic- and surgical procedure?
We should all be concerned about radiation. But we should not panic because we fear cancer. We have to balance the effects of radiation against the benefit derived. Unnecessary irradiation is of no positive value and should be avoided.
Cancer can be caused by radiation by damaging chromosomes. that risk can be stochastic which means there is no threshhold and the risk is not dose dependent or deterministic which means that risk is dose related.
We receive about 2 mSy per year in radiation from our surroundings, more if we are an airline pilot, or live at high altitude. That annual ambient dose is affected by the type of house we live in, by the use of smoke detectors and any number of other reasons.
the dose of an angiogram of the neck and chest generates about 5 millisievert, (mSy) which is a definition of dose absorbed.
Lets put that in perspective. The dose is about the same as 170 chest xrays. A head CT scan is 2 mSy, a chest CT 8mSy. Annual allowable occupation dose limit is 50 mSy. the LD50 is 5000 Sy.
The risk of additional cancer developing in a 40 year old man who has jugular venogram is 0.033% compared to the 50% probability that that man would develop cancer over the rest of his life.
So if we improve quality of life, or longevity of an MSer who is liberated, then the risk of the xrays necessary to do that treatment is worth taking.
2. Would you think that 3 Tesla MRV does offer reasonable better diagnostic possibilities in CCSVI than 1.5 Tesla MRV?
It would show plaques better. But it would not show iron deposits better, or the veins better. To the best of my knowledge, which I admit is not that great in MRI.
3. I know the following question is a somewhat delicate – if you don’t want to comment on it (especially in an open forum) I do understand that, anyway:
In one of your answers you stated that currently there is a periodic exchange of information between a core group of CCSVI researchers including Dr. Vogl from Germany. As I am from Germany he would be my preferred CCSVI contact.
a) Do you know whether Dr. Vogl was trained by Dr. Zamboni – in a talk Dr. Sandy McDonalds from Canada indicated that a proper ultrasound diagnosis would only be possible after one has been shown the relevant techniques in practice.
b) Do you know about the percentage rate at which Dr. Vogl does find relevant venous issues (CCSVI) in people with MS. About how many cases has he evaluated?
c) Some member here on TIMS wrote that Dr. Vogl does not evaluate the azygos vein, do you know if this was true/is still the case. One user also reported that he was examined in the payed CCSVI-program at BNAC and also his azygos was not taken into consideration – how comes?
d) Does Dr. Vogl currently use venogram for diagnosis, does he use IVUS – as you indicated in this thread – IVUS is important to further identify the nature of a narrowing?
e) Does he share your view that the relevant stenosis is the one that is located down in the jugular and upper vein restrictions might just be a consequence rather than the underlying cause?
To be honest, with all these questions I try to figure out whether I would currently be in good hands in Frankfurt – especially in terms of a meticulous diagnosis of CCSVI.
My RRMS has not been that very bad (EDSS about 2.5, DX 2002) and active so I do not feel too hard pressure to find a “solution” right NOW!, which does not mean I feel anyway near comfortable. I try to make the “right” choice…
Tomas is diligently trying to answer these questions, as am I. We discuss methodology of trials, methods of diagnosis and treatment. I do not feel qualified to judge his work at this point.
4. To me it currently seems as though “everyone” diagnosing CCSVI does it in a somewhat different way.
a) Could you guess the time-frame when we are going to have a standardized and largely accepted way to diagnose CCSVI.
b) Though the gold standard in CCSVI diagnosis is said to be venography, it seems to me that most sites rely on Doppler and MRV – how comes?
I would guess 3-5 years of study, papers, experience, dialogue and results.
Most sites still rely upon doppler and mrv because they are not invasive. Much of the initial fervor was directed at evaluating dr Zamboni's ultrasound findings. I suspect that that will abate some over the next several years and will depend upon who is interested in discovery. At the moment, I believe it is the interventionalists who are developing interest in ccsvi.
Thank you so much for your time and efforts. This discussion has helped me a lot with my understanding of CCSVI diagnosis and treatment.
it is my pleasure