A new SPECT/CT reconstruction algorithm: reliability and accuracy in clinical routine for non-oncologic bone diseases

Area of Science:

• Nuclear Medicine
• Medical Imaging
• Radiology

Background:

• Introduction of xSPECT Bone® (xB), a novel Siemens® reconstruction algorithm for SPECT/CT bone hybrid imaging.
• xB incorporates CT-based tissue segmentation for enhanced SPECT image visualization of bone anatomy.
• Study aims to compare the diagnostic reliability and accuracy of xB/CT against Flash 3D® (F3D)/CT in routine clinical practice.

Purpose of the Study:

• Assess the diagnostic reliability and accuracy of xB/CT reconstruction.
• Compare xB/CT performance with F3D/CT in non-oncological bone diseases.
• Evaluate inter-observer agreement and diagnostic confidence between the two reconstruction methods.

Main Methods:

• Retrospective analysis of 207 SPECT/CT scans from 213 patients with non-oncological bone diseases.
• Independent interpretation of scans by two nuclear medicine physicians (junior and senior) using xB/CT and F3D/CT.
• Inter-observer agreement (IOA) and diagnostic confidence assessed using McNemar test and Kappa coefficient.
• Validation through clinical and paraclinical follow-up exceeding 18 months.

Main Results:

• No statistically significant difference in IOA between xB/CT and F3D/CT (p = 0.532).
• High agreement for xB/CT (κ=0.89) and F3D/CT (κ=0.90) after categorical diagnosis classification.
• 31 discrepancies (14.9%) observed between reconstructions, with 21 (10.1%) classified as major.
• Follow-up confirmed diagnoses in 10 F3D/CT cases, 6 xB/CT cases, and was non-contributory in 5.

Conclusions:

• The xSPECT Bone® (xB) reconstruction algorithm is reliable for clinical use in SPECT/CT bone imaging.
• xB/CT offers high inter-observer agreement, comparable to F3D/CT.
• Diagnostic confidence with xB/CT is similar to that of F3D/CT in routine clinical settings.