Navigating a large-caliber catheter into the intracranial artery may generate a “ledge
effect,” which disturbs successful neurointervention. Particularly, navigation of
a large-lumen aspiration catheter is often required to achieve fast recanalization
in acute ischemic stroke cases. Occasionally, the aspirator cannot be passed through
the ophthalmic artery origin because of the ledge effect. Here, we report a new technique
for mitigation of the ledge effect that involves the use of double micro-guidewires
(MGWs). We refer to this technique as the “beanstalk method.” We evaluated the efficacy
of our idea using a silicon vascular model. Two 0.014” MGWs are used for navigation
of a 0.068” aspirator. After one guidewire is navigated to the distal portion, another
MGW is advanced along with the former guidewire, in a spiral fashion, similar to the
growth of a beanstalk. The aspirator can then pass with the coaxial double-guidewire,
although there is a severe gap in the vessel. We performed an in vitro study to demonstrate
the effectiveness of the beanstalk method. The beanstalk method was very useful, even
under challenging conditions that did not allow for passage of a conventional coaxial
catheter or buddy-wire. The beanstalk method effectively decreases the ledge effect
because of the shape of the two wires just ahead of the catheter, which contrasts
with the hardness of the spiral wires. In cases involving challenging vasculature,
the beanstalk method achieves smoother catheter navigation than the conventional coaxial
method or buddy-wire technique.
Key-words:
Beanstalk method - catheter - ledge effect - neurointervention
