Shaping and navigating methods of microcatheters for endovascular treatment of paraclinoid aneurysms

To determine whether the use of a specific shape and a navigating method of microcatheters are suitable for placement at paraclinoid aneurysms.

The clinical data from 122 patients with 132 paraclinoid aneurysms that underwent endovascular treatments during a 2.5-year period were retrospectively reviewed. Microcatheter shapes were classified as "straight," "primary curves" (45, 90, and J), "preshaped-C," "pigtail" (simple, right, and left), and "S" (simple, right, left, and preshaped). The navigating methods were classified as antegrade/retrograde microcatheter shift, wire-steering, looping, and coil/wire guiding. The shapes and navigating methods were compared among 3 aneurysm groups, which were categorized as superior, medial, and other, based on direction.

Shapes were significantly different between the 3 groups; the most commonly engaged shape in the superior group, medial group, and other group was S (55%), pigtail (60%), and primary (56%), respectively. The straight and S shapes were used in 5 (83%) and 18 (86%) cases, respectively, in the superior group, whereas the pigtail shape was used in 50 (86%) cases in the medial group. Aside from pigtail-simple shape, the side of pigtail, right vs left, coincided with the side of the internal carotid artery involved in every case of the medial group. The navigating methods were not significantly different among the 3 groups.

A specific shape by paraclinoid aneurysm direction tends to be suitable for the first trial of microcatheter shapes. Operators may reduce unnecessary struggling time of intra-aneurysmal placement of microcatheters by practicing the use of that shape.