New concept in neurovascular navigation: technical description and preclinical experience with the Bendit 17 and Bendit 21 microcatheters in a rabbit aneurysm model

Abstract

Background: Endovascular treatment of intracranial vascular diseases, such as aneurysms, is often challenged by unfavorable vascular anatomy. The Bendit Steerable Microcatheter (Bendit Technologies, Tel Aviv, Israel) has bending and torqueing capabilities designed to improve navigation and stability during device delivery, with or without a guidewire. We describe our preclinical experience with the Bendit 17 and Bendit 21 microcatheters in a rabbit aneurysm model.

Methods: Bifurcation and side wall aneurysms were created surgically in six New Zealand rabbits. We attempted to navigate Bendit devices through the vasculature and enter the aneurysms without a guidewire. Various positions within the aneurysm were selectively explored. Angiographic imaging was used to visualize catheterization, navigation, vascular manipulations, and placement of coils, stents, and intrasaccular devices.

Results: We successfully navigated the Bendit microcatheters to all aneurysms without a guidewire. We successfully recanalized a nearly occluded carotid artery and navigated the Bendit through a braided stent. In contrast, we were unable to navigate a comparator device with a guidewire as effectively as the Bendit. Coils were introduced at different locations within the aneurysm and could be pushed, pulled, and repositioned with the Bendit tip. Finally, we used the Bendit to deliver intrasaccular devices designed for terminal aneurysms to treat side wall aneurysms.

Conclusions: Bendit's bending and torqueing abilities, combined with its stability in the bent position, enable quick navigation and optimal deployment of devices. Clinical studies are necessary to determine whether these navigation advantages lead to more efficient treatment of intracranial and peripheral aneurysms.

Keywords: aneurysm; catheter; coil; guidewire; stent.

Figure 1

General dimensions of the (A) Bendit 17 and (B) Bendit 21 microcatheters. (C) The manual control for the Bendit. Moving the sliding button up and down bends the tip 180° in either direction. The rotating knob allows the device to be torqued.

Figure 2

(A) The Bendit 17 used to catheterize the left carotid artery in a rabbit bifurcation aneurysm without a guidewire. (B) The Bendit 17 tip pointed precisely at the 2:00 position without a guidewire. (C) The Bendit 17 is rotated around the entire circumference of the vessel above a side wall aneurysm without any vessel spasms.

Figure 3

(A) The Bendit 17 can be navigated through a braided LVIS stent to reach the aneurysm, without a guidewire. (B) The Bendit 17 can be maneuvered through a braided LVIS Jr stent to enter the left carotid artery without a guidewire. (C, D) The Bendit 17 was twice able to access a nearly occluded right carotid artery and gain access to the lumen without a guidewire. The Headway 21, a comparator device with a guidewire, could not be used to cross the area of stenosis. (E) The Bendit 17 used to deploy the LVIS 4.5 stent along the right carotid artery in a steady manner.

Figure 4

(A) The Bendit 17 can be used to position coils precisely in the dome of the aneurysm. (B) The Bendit 17 was used to reposition the coils within the aneurysm from (A) by pulling them toward the base. (C) The Bendit was used to reposition the coils from (B) back toward the dome of the aneurysm.