Ceramic aneurysm clips

Abstract

Objective: To design and manufacture an aneurysm clip that incorporates ceramic jaws and a titanium spring, thereby decreasing susceptibility artifact at the aneurysm neck and allowing intra- and/or postoperative magnetic resonance (MR) evaluation.

Methods: A series of aneurysm clips were developed using ceramic jaws and a titanium spring. A corresponding clip applicator with a novel clip-applicator interface was developed to improve ergonomics and visibility during clip placement or removal. Ceramic clips were imaged at 3.0 T in a kiwi fruit phantom model and compared with MR-compatible Yaşargil aneurysm clips (Aesculap, AG & Co., Tuttlingen, Germany). Ceramic clips were subsequently evaluated in a human cadaveric model at 1.5 T.

Results: Ceramic clips were developed initially using silicon nitride ceramic and subsequently with yttria-stabilized zirconia ceramic. The ceramic clip jaws showed reduced susceptibility artifact compared with MR-compatible Yaşargil clips. Closing pressure was maintained over the course of 50 cycles of clip opening and closing. Aneurysm clip jaw crossing was not observed. The novel clip applicator and enhanced applicator-clip interface improved visibility during clip application and reduced the potential for torque during clip removal.

Conclusion: The use of ceramic material limited MR imaging susceptibility artifact and image distortion in the area immediately surrounding the ceramic jaws. As expected, image distortion occurred around the titanium spring and pivot. However, in the unique design of this new aneurysm clip, the spring is located far enough from the distal end of the jaws to provide an undistorted image of the clipped area.