Visual MRI Grading System to Evaluate Atrophy of the Supraspinatus Muscle.
10.3348/kjr.2014.15.4.501
- Author:
Hyun Kyong LIM
1
;
Sung Hwan HONG
;
Hye Jin YOO
;
Ja Young CHOI
;
Sae Hoon KIM
;
Jung Ah CHOI
;
Heung Sik KANG
Author Information
1. Department of Radiology, Seoul National University College of Medicine, Seoul 110-744, Korea. drhong@snu.ac.kr
- Publication Type:Original Article
- Keywords:
Rotator cuff tear;
Supraspinatus muscle;
Muscular atrophy;
Magnetic resonance imaging;
Occupation ratio
- MeSH:
Adult;
Aged;
Feasibility Studies;
Female;
Humans;
Joint Diseases;
Magnetic Resonance Imaging;
Male;
Middle Aged;
Muscular Atrophy/diagnosis/*pathology;
Observer Variation;
Reference Standards;
Reproducibility of Results;
Retrospective Studies;
Rotator Cuff/*pathology;
Young Adult
- From:Korean Journal of Radiology
2014;15(4):501-507
- CountryRepublic of Korea
- Language:English
-
Abstract:
OBJECTIVE: To investigate the interobserver reproducibility and diagnostic feasibility of a visual grading system for assessing atrophy of the supraspinatus muscle on magnetic resonance imaging (MRI). MATERIALS AND METHODS: Three independent radiologists retrospectively evaluated the occupying ratio of the supraspinatus muscle in the supraspinatus fossa on 192 shoulder MRI examinations in 188 patients using a 3-point visual grading system (1, > or = 60%; 2, 30-59%; 3, < 30%) on oblique sagittal T1-weighted images. The inter-reader agreement and the agreement with the reference standard (3-point grades according to absolute occupying ratio values quantitatively measured by directly contouring the muscles on MRI) were analyzed using weighted kappa. The visual grading was applied by a single reader to a group of 100 consecutive patients who had undergone rotator cuff repair to retrospectively determine the association between the visual grades at preoperative state and postsurgical occurrences of retear. RESULTS: The inter-reader weighted kappa value for the visual grading was 0.74 when averaged across three reader pairs (0.70-0.77 for individual reader pairs). The weighted kappa value between the visual grading and the reference standard ranged from 0.75 to 0.83. There was a significant difference in retear rates of the rotator cuff between the 3 visual grades of supraspinatus muscle atrophy on MRI in univariable analysis (p < 0.001), but not in multivariable analysis (p = 0.026). CONCLUSION: The 3-point visual grading system may be a feasible method to assess the severity of supraspinatus muscle atrophy on MRI and assist in the clinical management of patients with rotator cuff tear.
