A New MRI Grading System for Cervical Foraminal Stenosis Based on Axial T2-Weighted Images.
10.3348/kjr.2015.16.6.1294
- Author:
Sujin KIM
1
;
Joon Woo LEE
;
Jee Won CHAI
;
Hye Jin YOO
;
Yusuhn KANG
;
Jiwoon SEO
;
Joong Mo AHN
;
Heung Sik KANG
Author Information
1. Department of Radiology, Seoul National University Bundang Hospital, Seoul National University College of Medicine, Institute of Radiation Medicine, Seoul National University Medical Research Center, Seongnam 13620, Korea. joonwoo2@gmail.com
- Publication Type:Original Article
- Keywords:
Cervical spine;
Neural foraminal stenosis;
Severity grading system;
Classification
- MeSH:
Aged;
Aged, 80 and over;
Female;
Humans;
*Magnetic Resonance Imaging;
Male;
Middle Aged;
Reproducibility of Results;
Severity of Illness Index;
Spinal Stenosis/pathology/*radiography
- From:Korean Journal of Radiology
2015;16(6):1294-1302
- CountryRepublic of Korea
- Language:English
-
Abstract:
OBJECTIVE: The purpose of this study was to evaluate the reliability of a new magnetic resonance imaging (MRI) grading system for cervical neural foraminal stenosis (NFS). MATERIALS AND METHODS: Cervical NFS at bilateral C4/5, C5/6, and C6/7 was classified into the following three grades based on the T2-weighted axial images: Grade 0 = absence of NFS, with the narrowest width of the neural foramen greater than the width of the extraforaminal nerve root (EFNR); Grade 1 = the narrowest width of the neural foramen the same or less than (but more than 50% of) the width of the EFNR; Grade 2 = the width of the neural foramen the same or less than 50% of the width of the EFNR. The MRIs of 96 patients who were over 60 years old (M:F = 50:46; mean age 68.4 years; range 61-86 years) were independently analyzed by seven radiologists. Interobserver and intraobserver agreements were analyzed using the percentage agreement, kappa statistics, and intraclass correlation coefficient (ICC). RESULTS: For the distinction among the three individual grades at all six neural foramina, the ICC ranged from 0.68 to 0.73, indicating fair to good reproducibility. The percentage agreement ranged from 60.2% to 70.6%, and the kappa values (κ = 0.50-0.58) indicated fair to moderate agreement. The percentages of intraobserver agreement ranged from 85.4% to 93.8% (κ = 0.80-0.92), indicating near perfect agreement. CONCLUSION: The new MRI grading system shows sufficient interobserver and intraobserver agreement to reliably assess cervical NFS.
