Normal rotator cuff: MR imaging with conventional and fat-suppression techniques.

Area of Science:

• Radiology
• Musculoskeletal Imaging
• Orthopedics

Background:

• Magnetic resonance (MR) imaging is crucial for diagnosing rotator cuff disorders.
• Interpreting subtle signal intensities and morphologic characteristics is key to accurate diagnosis.
• Previous MR imaging findings sometimes led to misinterpretation as rotator cuff abnormalities.

Purpose of the Study:

• To investigate signal intensity and morphologic characteristics of the rotator cuff in asymptomatic subjects using MR imaging.
• To differentiate normal rotator cuff findings from potential abnormalities.
• To refine diagnostic criteria for rotator cuff disorders using MR imaging.

Main Methods:

• Fifteen asymptomatic subjects underwent MR imaging.
• Five different pulse sequences were utilized to assess the rotator cuff and surrounding structures.
• Analysis focused on signal intensity and morphologic features, particularly in the critical zone.

Main Results:

• A focal region of increased signal intensity was consistently observed in the supraspinatus tendon's critical zone.
• Specific soft-tissue signal intensities were identified between tendon layers and near the cuff insertion.
• Fat-suppression imaging enhanced the conspicuity and definition of these regions and small fluid collections.

Conclusions:

• The observed signal intensities and morphologic characteristics represent normal findings in asymptomatic rotator cuffs.
• Fat-suppression techniques are valuable for clearly visualizing these normal structures.
• These findings aid in refining MR imaging criteria to avoid misdiagnosis of rotator cuff abnormalities.