2228. Qualitative and Quantitative Differentiation of Benign and Malignant Vertebral Compression Fractures Using a Single FSE T2-w Dixon Sequence
Authors * Denotes Presenting Author
  1. Sébastien Bacher; Lausanne University Hospital
  2. Steven Hajdu; Lausanne University Hospital
  3. Yael Maeder; Lausanne University Hospital
  4. Vincent Dunet; Lausanne University Hospital
  5. Patrick Omoumi *; Lausanne University Hospital
The differentiation of benign and malignant vertebral compression fractures (VCF) is a common clinical problem and relies on qualitative and quantitative assessment of different MRI sequences. The objective of this study was to determine and compare the qualitative and quantitative diagnostic performance of a single sagittal fast spin echo (FSE) T2-weighted Dixon sequence in differentiating benign and malignant VCF, with multiple readers and different quantitative methods.

Materials and Methods:
From July 2014 to October 2019, 90 consecutive patients with spine MRI performed prior to cementoplasty for acute VCF were retrospectively included. VCFs were categorized as benign (n=61, mean age=75.5±11.7years) or malignant (n=29, mean age=63.7±12.4years) based on the reference standard (biopsy and/or =9months clinical/imaging follow-up). Qualitative analysis was independently performed by four radiologists by categorizing each VCF as either benign or malignant using only the image sets provided by FSE T2-weighted Dixon sequences. Quantitative analysis was performed using two different regions of interest (ROI1-2), and three methods (signal drop, fat fraction (FF) from ROIs, FF from maps). Diagnostic performance was compared using ROC curves analyses. Interobserver agreement was assessed using kappa statistics and intraclass correlation coefficients (ICC).

The qualitative diagnostic performance ranged from AUC=0.97 (95%CI:0.92-1.00) to AUC=0.99 (95%CI:0.98-1.0). The quantitative diagnostic performance ranged from AUC=0.82 (95%CI:0.72-0.92) to AUC=0.96 (95%CI:0.92-0.99). Pairwise comparisons showed no statistically significant difference in diagnostic performance (all p=0.002, Bonferroni corrected p<0.0011). Five out of five cases for which readers disagreed were correctly diagnosed at quantitative analysis using ROI2. Interobserver agreement was excellent for both qualitative and quantitative analysis.

A single FSE T2-weighted Dixon sequence can be used to differentiate benign and malignant VCFs with high diagnostic performance, and high interobserver agreement, both at qualitative and quantitative analysis. The quantitative analysis measuring signal drop and fat fraction provides complementary information to the qualitative analysis (correctly diagnosing up to 5 cases of disagreement at qualitative analysis).