During the procedure, the patients are mildly sedated and closely monitored. After local anesthesia at the level of the groin, an introducer sheath is placed in the femoral artery. A catheter with a balloon tip is advanced through the sheath and navigated to the affected carotid artery. A metallic mesh (stent) is advanced through the catheter and then deployed at the level of the stenotic vessel segment. During the procedure, parts of the vessel wall plaques can break loose and can be washed upstream into the brain where they may cause a stroke. To minimize this risk, safety systems are used (1) proximal protection with a balloon tip catheter and (2) distal protection with a "filter".
Demonstration of endovascular treatment of narrowed neck vessels by stent implantation
(A) Plaques which have formed within the vessel wall are clogging the internal carotid artery (yellow). During the procedure, a balloon tip catheter is placed below the stenosis and a filter is placed above the clogged segment. The balloon can temporarily be inflated during the procedure and prevent plaque debris from being washed into the brain
(B) The stent is deployed at the level of the stenosis and if necessary expanded with a balloon to improve stent opening and wall apposition. If parts of the plaque break loose during the procedure, they get caught in the filter, which can then be removed together with the debris.
(C) In this illustration, the blood flow to the brain is completely blocked for a short period of time by means of two balloons, which reduces the risk of plaque debris being washed into the brain.
