Repeatability of T1-quantification in dGEMRIC for three different acquisition techniques: two-dimensional inversion...

Area of Science:

• Orthopedics
• Radiology
• Biomedical Engineering

Background:

• Osteoarthritis (OA) is a degenerative joint disease.
• Accurate cartilage assessment is crucial for OA management.
• Delayed gadolinium enhanced MRI of cartilage (dGEMRIC) is a quantitative MRI technique for assessing cartilage matrix composition.

Purpose of the Study:

• To evaluate the repeatability of dGEMRIC in osteoarthritis-prone knee joints.
• To compare three T1 quantification techniques: 2D inversion recovery (2D-IR), 3D Look-Locker (3D-LL), and 3D variable flip angle (3D-VFA).

Main Methods:

• Nine subjects with osteoarthritis-prone knees underwent two dGEMRIC scans with a 2-week interval.
• T1 quantification was performed using 2D-IR, 3D-LL, and 3D-VFA techniques.
• Repeatability was assessed using root-mean-square coefficient of variation (CV(RMS)) and intraclass correlation coefficient (ICC) in defined cartilage regions.

Main Results:

• 2D-IR and 3D-LL showed comparable repeatability (CV(RMS) 5.4-8.4%) with moderate reliability (ICC).
• 3D-VFA exhibited higher CV(RMS) (9.3-15.2%) and low reliability (ICC).
• Inter-slice variation for 3D techniques was similar in magnitude to overall repeatability.

Conclusions:

• 2D-IR and 3D-LL are reliable techniques for repeatable dGEMRIC measurements in osteoarthritis-prone knees.
• 3D-VFA is less reliable for dGEMRIC quantification in this context.
• Precise image positioning is critical for achieving reliable dGEMRIC repeatability results.