Published in:
01-04-2018 | Magnetic Resonance
Sciatic neurosteatosis: Relationship with age, gender, obesity and height
Published in: European Radiology | Issue 4/2018
Login to get accessAbstract
Aim
To evaluate inter-reader performance for cross-sectional area and fat quantification of bilateral sciatic nerves on MRI and assess correlations with anthropometrics.
Methods
In this IRB-approved, HIPPA-compliant study, three readers performed a cross-sectional analysis of 3T lumbosacral plexus MRIs over an 18-month period. Image slices were evaluated at two levels (A and B). The sciatic nerve was outlined using a free hand region of interest tool on PACS. Proton-density fat fraction (FF) and cross-sectional areas were recorded. Inter-reader agreement was assessed using intra-class correlation coefficient (ICC). Spearman correlation coefficients were used for correlations with age, BMI and height and Wilcoxon rank sum test was used to assess gender differences.
Results
A total of 67 patients were included in this study with male to female ratio of 1:1. Inter-reader agreement was good to excellent for FF measurements at both levels (ICC=0.71–0.90) and poor for sciatic nerve areas (ICC=0.08–0.27). Positive correlations of sciatic FF and area were seen with age (p value<0.05). Males had significantly higher sciatic intraneural fat than females (p<0.05).
Conclusion
Fat quantification MRI is highly reproducible with significant positive correlations of sciatic FF and area with age, which may have implications for MRI diagnosis of sciatic neuropathy.
Key Points
• MR proton density fat fraction is highly reproducible at multiple levels.
• Sciatic intraneural fat is positively correlated with increasing age (p < 0.05).
• Positive correlations exist between bilateral sciatic nerve areas and age (p < 0.05).
• Males had significantly higher sciatic intraneural fat than females (p < 0.05).