Vascular access ports and catheters: ex vivo testing of ferromagnetism, heating, and artifacts associated with MR imaging.

Abstract

The purpose of this study was to evaluate ferromagnetic qualities, heating, and artifacts associated with MR imaging of implantable vascular access ports (IVAPs, N = 9) and catheters (N = 8). Ferromagnetism was determined using previously described techniques. Heating was assessed for the IVAPs by measuring temperature immediately before and after performing a 3D GRASS, MTC pulse sequence for 60 min at an SAR of 2.8 W/kg. Artifacts were evaluated in association with the use of a fast GRASS pulse sequence and graded according to the severity of image distortion. None of the IVAPs or catheters were attracted by the magnetic field of the MR system. The largest temperature change measured was -0.3 degree C. Artifacts varied, depending on the component materials used for the construction of the IVAPs and catheters. The lack of ferromagnetic qualities and negligible heating indicates that MR imaging performed at 1.5 T or less may be conducted safely in patients with each of the IVAPs and catheters tested. None of the artifacts produced by the presence of the IVAPs or catheters is considered to impair the diagnostic aspects of MR imaging, especially if the device is not positioned directly in the imaging area of interest.