High-Resolution Qualitative and Quantitative Magnetic Resonance Evaluation of the Glenoid Labrum.

Kenyu Iwasaki,Christine B Chung,Reni Biswas,Sheronda Statum,Eric Y Chang,Won C Bae,Graeme M Bydder,Jiang Du,Betty Tran,Monica Tafur

doi:10.1097/rct.0000000000000307

Abstract

This study aimed to implement qualitative and quantitative magnetic resonance sequences for the evaluation of labral pathology. Six glenoid labra were dissected, and the anterior and posterior portions were divided into normal, mildly degenerated, or severely degenerated groups using gross and magnetic resonance findings. Qualitative evaluation was performed using T1-weighted, proton density-weighted, spoiled gradient echo and ultrashort echo time (UTE) sequences. Quantitative evaluation included T2 and T1rho measurements as well as T1, T2*, and T1rho measurements acquired with UTE techniques. Spoiled gradient echo and UTE sequences best demonstrated labral fiber structure. Degenerated labra had a tendency toward decreased T1 values, increased T2/T2* values, and increased T1rho values. T2* values obtained with the UTE sequence allowed for delineation among normal, mildly degenerated, and severely degenerated groups (P < 0.001). Quantitative T2* measurements acquired with the UTE technique are useful for distinguishing among normal, mildly degenerated, and severely degenerated labra.

Highlights

The glenoid labrum is a vascularized rim of fibrous tissue that outlines the bony glenoid[1]
Quantitative T2* measurements acquired with the ultra-short echo time (UTE) technique are useful for distinguishing between normal, mildly degenerated and severely degenerated labra
Three ROIs were classified as normal, four ROIs were classified as degeneration of labrum and 5 ROIs were classified as osteoarthritis (Table 2)

Summary

Introduction

The glenoid labrum is a vascularized rim of fibrous tissue that outlines the bony glenoid[1]. It plays an important role in deepening the glenoid fossa and increases the articulating surface area of the glenoid to help prevent glenohumeral instability. The core structure of the labrum is composed of collagen fiber bundles that run in a circumferential orientation around the glenoid rim. These circumferential collagen fibers intermingle with radially orientated fibers at the biceps tendon insertion[2, 4]. The majority of collagen fibrils are composed of type I collagen, but type II collagen is present in a smaller amount[5]

Methods

Results

Conclusion