Articular cartilage defects: detectability in cadaver knees with MR

Area of Science:

• Orthopedic Imaging
• Magnetic Resonance Imaging (MRI)
• Biomedical Engineering

Background:

• Focal defects in articular cartilage are challenging to detect using standard MRI.
• Accurate detection is crucial for timely diagnosis and treatment of joint injuries.

Purpose of the Study:

• To evaluate the efficacy of 1.5-T MRI in detecting focal articular cartilage defects.
• To compare the performance of intraarticular saline and gadolinium-DTPA (Gd-DTPA) as contrast agents.
• To determine optimal MRI pulse sequences for cartilage defect visualization.

Main Methods:

• Cadaveric knees with surgically created femoral articular cartilage defects (1-5 mm) were imaged.
• Images were acquired using various pulse techniques, slice thicknesses, and signal excitations.
• Intraarticular saline and Gd-DTPA were injected, and their signal behavior was compared to hyaline cartilage.

Main Results:

• All defects were undetectable on T1-weighted and balanced images without Gd-DTPA.
• Intraarticular saline identified only 3 mm defects on T2-weighted images.
• Intraarticular Gd-DTPA enabled detection of defects as small as 2 mm, with high signal intensity differences across all sequences.

Conclusions:

• Intraarticular fluid and optimized MRI sequences are essential for detecting focal articular cartilage defects.
• Intraarticular Gd-DTPA is the superior contrast agent for visualizing these defects.
• 1.5-T MRI with Gd-DTPA enhances diagnostic accuracy for cartilage lesions.