Magnetic resonance imaging (MRI) has been used increasingly in recent years since introduction of titanium-based implants with reduced artifact compared to formerly used stainless-steel devices. These artifacts could be decreased even more by changing imaging parameters such as reducing echo time, increasing bandwidth and decreasing voxel size. Aligning the implant along the axis of the magnetic field also reduces artifact although it is often not completely achievable due to the multidirectional configuration of most hardware. Spin echo sequences are less vulnerable to magnetic susceptibility artifact and give better quality images compared with gradient echo sequences. MRI is useful in detecting infection (Figure 9) and assessing recurrent tumor. MRI is the modality of choice in assessing intraspinal contents. Myelography (Figure 6) is an alternative when MRI is contraindicated or is nondiagnostic because of artifact.