Orthopedic Spinal and Hip Prostheses: Effects of Magnetic Susceptibility Artifacts during MR Arteriography and Venography of Abdomen and Pelvis

Abstract

To retrospectively determine if susceptibility artifacts from internal metallic spinal fixation devices and hip prostheses limit the depiction of vascular anatomy and pathologic abnormalities during magnetic resonance (MR) arteriography and venography. This study was approved by the Committee on Human Research of the Institutional Review Board, which waived the requirement for informed consent and deemed the study to be HIPAA compliant. Forty-two contrast material-enhanced MR angiographic examinations were performed by using a 1.5-T imager in 41 patients (16 men, 25 women; mean age, 57 years; range, 36-79 years); 33 of these examinations included both MR arteriographic and MR venographic components. On the basis of resolution, images for which more than 3 mm of vessels were affected by susceptibility artifacts were considered uninterpretable. The odds of obtaining an uninterpretable image due to metallic artifacts were calculated, and a chi(2) analysis was employed to determine significance. Total hip prostheses and spinal hardware that terminated above the L5 level did not generate any appreciable artifacts at MR arteriography (P < .001) or MR venography (P = .002). In patients with hardware that extended to the sacrum, 88% of MR arteriograms were of diagnostic quality (P = .001), but only 21% of MR venograms were interpretable (P = .004). Artifacts limited the evaluation of the inferior vena cava and common iliac veins near the confluence. Diagnostic-quality MR arteriograms and MR venograms can be obtained in patients with artificial hip prostheses and spinal hardware terminating above the L5 level, but there is 79% likelihood of obtaining a nondiagnostic MR venogram in patients with internal spinal fixation devices that extend to the sacrum.