Comparison of FRACTURE MRI, Conventional Radiography, and CT in the Evaluation of Bone Tumors

Abstract

Purpose: To evaluate the intermodality and interobserver agreement of fast field echo resembling a CT using restricted echo-spacing (FRACTURE) MRI with conventional radiography and CT in assessing bone tumors. Materials and Methods: This retrospective study included patients with histopathologically confirmed bone tumors who underwent FRACTURE MRI and radiography over a 10-month period; a subset also underwent CT. Two independent readers assessed lesion features across modalities, with agreement calculated using Cohen κ. Results: Among 161 patients (median age, 18 years [IQR, 13.5–31]; 95 male), FRACTURE showed near-perfect/perfect agreement with conventional radiography for lesion type (κ = 0.96 and 0.86, for reader 1 and reader 2, respectively) and treatment response (κ = 1.00, 1.00), near-perfect/substantial agreement for both fractures (κ = 0.95, 0.76) and lesion location (κ = 0.95, 0.79), and near-perfect/moderate agreement for matrix content (κ = 0.89, 0.56). Agreement was substantial for extraosseous soft tissue (κ = 0.74, 0.65) and osteochondral defects (κ = 0.75, 0.75) and moderate for lesion margins (κ = 0.42, 0.59). Cortical integrity showed moderate to near-perfect agreement (range, κ = 0.46–0.85) and periosteal reactions fair to near-perfect agreement (range, κ = 0.34–0.91), depending on subtype and reader. In the CT subset (n = 69), FRACTURE maintained near-perfect/perfect agreement for lesion type (κ = 0.90, 0.84), location (κ = 1.00, 0.94), extraosseous soft tissue (κ = 0.96, 0.85), fractures (κ = 0.95, 0.96), treatment response (κ = 1.00, 1.00), and osteochondral defects (κ = 1.00, 1.00). Near-perfect/substantial agreement was present for matrix content (κ = 0.81, 0.61). Cortical integrity and periosteal reaction showed fair to near-perfect agreement (range, κ = 0.25–0.81, 0.33–0.91). Conclusion: FRACTURE MRI demonstrated high agreement with radiography and CT in evaluating most bone tumor features.