Treatment of aneurysms and other neurological conditions would benefit from improved guidance of wires in arteries and the resulting reduction in time required to insert catheters and other imaging or treatment devices. By making a small opening in a blood vessel in the groin/upper thigh, arm, or neck, a catheter can be inserted with a guide wire to maneuver the catheter to the desired site. The ability to navigate arteries more accurately and thus insert a catheter more quickly would reduce the probability of aneurysm rupture and thus has the potential to reduce the rate of fatality or neurological deficit. This technology can also be used to treat complex aneurysms such as wide neck bifurcation aneurysms by angulating the neck of aneurysm temporarily. Nitinol is a shape memory alloy of nickel and titanium, with a long record of biocompatibility, particularly when an oxide and/or another passivating layer is applied. Nitinol coils have been used widely as stents because the alloy can be programmed to expand at human body temperatures and solidly fix to blood vessel walls. In this work, Nitinol wire is used with a programmed heat activation above body temperature, and thus guidance can be externally controlled using resistive heating. We present results of current-controlled steering of Nitinol wire, including the programming, control, and material response to varying current levels and pulse durations. We also demonstrate the viability of a light emitting diode attached to the guidewire with additional potential for image guidance, catheter navigation, and other treatment techniques.
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