High-pressure balloons for CCSVI – a necessity for proper treatment
In CCSVI treatment, veins in the thorax and neck area are dilated with balloons.
The intention of course is to facilitate the drainage of blood.
This blood drainage is hindered by narrowing in the vessels (= veins) and by valves
that do not open sufficiently. This causes restriction in the drainage of blood,
which seeks a route via collaterals; these are side branches and connections to
veins that already exist, which become wider and larger to gain more capacity to
transport the blood away. The actual vein itself may finally collapse because it
is transporting away little or no blood. It seldom or never happens that this vein
blocks up completely, so that nothing can flow through it any more.
In the treatment of CCSVI, we track down the veins with a guide wire and catheter,
in order then to be able to inject contrast agent, which allows us to obtain an
image of the veins and any collaterals. The contrast agent behaves just like blood,
so we can see the speed with which it flows away, and the route it takes on its
way. We thus obtain a realtime functional image of the blood drainage. The next
thing is to analyse the images to determine the reason why the contrast agent chooses
another route, or does not flow away quickly enough, or even remains behind in the
vein.
Frequently there are constrictions or poorly-functioning valves low down in the
neck. The constriction is often very short and ring-shaped at the place where the
valves are attached to the vein wall. Poorly-operating valves are usually ones that
open insufficiently, perhaps due to deformation or scarring.
We know that restrictions in veins are hard to stretch open. It is essential to
use a balloon that is large enough compared to the patient’s veins. Also, the balloon
has to be inflated for long enough to give the tissue enough time to stretch open.
Moreover, you must be able to apply enough pressure to the balloon to allow sufficient
force to be developed to break the fibres that are causing the narrowing or deformation.
The average diameter of the jugular vein is 12 to 14 mm. The pressure needed to
force open a restriction in a vessel can easily reach 10 to 14 atmospheres. These
are very high pressures, for which it is essential to have a balloon that retains
its own diameter and does not burst at these pressures.
- Contrast injected into the vessel flows away via collaterals; limited narrowing
but probably the valve system is not opening completely
- Balloon with a dent where the restriction is
- Balloon completely opened out; here this was at 14 atmospheres
- Follow-up image after use of the balloon: good drainage of contrast back to the
heart; vessel is wide open.
In practice, during the inflation of a well-chosen balloon, you see that it inflates
first in front of and behind the deficit. By well-chosen, I mean its diameter compared
to the vessel. A dent remains in the balloon at the position of the narrowing or
stenosis. Then the pressure in the balloon is increased until this dent disappears
(usually 12 to 14 atmospheres, and sometimes more). Next you look at the pressure
meter you used to inflate the balloon, and you usually see some pressure drop happening
as a few more fibres part. Then you apply a little more pressure back to that where
the balloon became fully open. Finally you maintain this for a minute or two until
the situation is stable without pressure drop.
In my opinion this is the best way of working, in which you of course must have
balloons that are large enough and can withstand such pressures. These are known
in the profession as high-pressure balloons.
Many centres make use of smaller balloons as an alternative, and use two of them
next to each other. An extra guide wire may also be inserted alongside the balloons
to create extra force to break the fibres that are causing the restriction: the
extra wire has a kind of cutting effect. These are both recognised and practical
alternatives, but they remain alternatives that you should use if the first logical
step does not work, this being a balloon that is large and powerful enough.
The disadvantage of the high-pressure balloon is that it is much stiffer and more
awkward than the others, particularly in these large diameter sizes. There is simply
more material needed to create a large, strong balloon. The vessels, however, are
large flexible routes into which such balloons can be inserted without difficulty.
More information:
CCSVI Online – Privatescan B.V.
Telefoon: +31 - 74 - 255 26 80
Email: info@privatescan.nl
Website: www.ccsvi-online.com
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