An Introduction to a New Family of Palladium Based Medical Alloys

Interest has been increasing in palladium based medical alloys, primarily because they offer cost savings over traditional platinum based medical alloys. This work presents an overview of the palladium based alloys, Paliney In Vivo 500, 1100, and 1200. The attributes discussed are biocompatibility, mechanical properties, electrochemical properties, radiopacity, and MRI compatibility. Understanding these properties is critical in helping the device developer choose appropriate materials for a given application. For instance, the importance of understanding the response of metallic implants during magnetic resonance imaging (MRI) has increased with its ubiquitous use in the clinical setting. As a base of comparison, the properties of the Paliney In Vivo alloys are contrasted to conventional medical alloys, such as, Pt – 10.5% Ni, Pt – 10% and 20% Ir, Pt – 8% W, MP35N, Elgiloy and Inconel 625. In most cases, the appropriate Paliney In Vivo alloy has equivalent or improved performance compared to the platinum based alloys. Additionally, both the platinum and palladium based alloys are shown to have improved radiopacity and MRI imaging characteristics in comparison to both the Fe and Co based alloys. Under typical clinical conditions, a reduced magnetic susceptibility of the base alloy produced a smaller MRI ghost image. The nickel and cobalt bearing alloys have higher magnetic susceptibility and dramatically larger phantom image size.