Does a knee MRI need to be performed with or without contrast?

Knee MRI Should Be Performed WITHOUT Contrast

For the vast majority of knee pathology, MRI without IV contrast is the standard and appropriate imaging approach, as recommended by the American College of Radiology. 1, 2, 3

Standard Protocol: Non-Contrast MRI

MRI without contrast effectively evaluates all common knee pathology including:

• Meniscal tears – Non-contrast sequences provide excellent visualization of meniscal morphology and signal abnormalities 1, 3
• Ligament injuries (ACL, PCL, MCL, LCL) – Ligament integrity and tears are accurately assessed without contrast enhancement 1, 3, 4
• Cartilage damage – Chondral lesions and cartilage thinning are adequately visualized on standard sequences 1, 3
• Bone marrow edema – Stress fractures, bone bruises, and subchondral insufficiency fractures are well-demonstrated without contrast 3, 5
• Osteochondritis dissecans and loose bodies – Osseous fragments have inherent signal characteristics that provide excellent contrast against surrounding tissues without IV gadolinium 2, 3
• Tendon pathology – Patellar and quadriceps tendinopathy or tears require no contrast 3
• Post-surgical evaluation – Assessment after meniscal repair, ligament reconstruction, or total knee arthroplasty is performed without contrast 1, 3

When Contrast IS Indicated (Rare Scenarios)

Contrast-enhanced MRI or MR arthrography should be reserved for specific situations:

• MR arthrography (intra-articular gadolinium) – Only for patients with prior meniscal surgery when re-tear is suspected, or for detailed chondral lesion mapping 3
• Synovial proliferative disorders – Pigmented villonodular synovitis (PVNS) requires contrast to assess extent and vascularity 3
• Neoplastic masses – Tumor characterization benefits from contrast enhancement 3
• Quantifying synovitis – When precise grading of inflammatory synovitis is needed for treatment decisions, though this correlates only moderately with histology 3

ACR Appropriateness Criteria Summary

The American College of Radiology explicitly states that MRI without and with IV contrast is NOT usually indicated for evaluating chronic knee pain or osseous knee injuries 1, 2. The ACR recommendations are based on 28 well-designed or good-quality studies published through 2018 1.

Clinical Algorithm

1. Start with plain radiographs – Initial imaging for all knee pain to identify fractures, degenerative changes, loose bodies, or effusions 1, 6
2. Order MRI WITHOUT contrast if radiographs show:
   • Joint effusion 1
   • Osteochondritis dissecans 1
   • Loose bodies 1
   • Signs of prior osseous injury (Segond fracture, tibial spine avulsion) 1
   • Normal findings but high clinical suspicion for internal derangement 1
3. Consider contrast only if specific indications listed above are present after reviewing the non-contrast study 3

Common Pitfall to Avoid

Do not routinely order contrast-enhanced knee MRI "just to be thorough." Contrast adds cost, time, and potential adverse effects without improving diagnostic accuracy for standard knee pathology 1, 2, 3. The inherent tissue contrast of bone, cartilage, menisci, and ligaments on standard sequences is sufficient for diagnosis 2, 5.