MRI blind zone: A proposed novel index for spinal implants artifacts

Area of Science:

• Medical Imaging
• Biomedical Engineering
• Orthopedic Surgery

Background:

• Metallic implants in spinal surgery can cause significant artifacts on Magnetic Resonance Imaging (MRI).
• These artifacts obscure critical anatomical structures, complicating post-operative assessment.
• Predicting and quantifying these artifacts is essential for patient management.

Purpose of the Study:

• To introduce and advocate for a novel index, the MRI Blind Zone.
• This index aims to predict the dimensions of MRI artifacts caused by spinal implants.
• It also seeks to identify obscured organs of interest due to these artifacts.

Main Methods:

• Retrospective analysis of post-operative MRI scans from patients with various spinal implants.
• Detailed description and measurement of the MRI blind zone for different implant types.
• Development of a proposed 3D model for standardized industry reporting.

Main Results:

• Seven distinct implant types were analyzed, detailing their associated post-operative MRI artifacts.
• The study highlights the clinical implications of these artifacts.
• Implant material, processing, and patient anatomy significantly influence artifact size and obscured regions.

Conclusions:

• MRI artifact is a complex phenomenon influenced by implant characteristics (shape, size, material, processing) and patient anatomy.
• Different implants produce varying degrees of artifact, impacting clinical decisions, especially for post-operative imaging.
• A standardized MRI Blind Zone index is needed for efficient implant comparison and informed surgical decision-making.