Dual-Layer Spectral Detector Computed Tomography Quantitative Parameters: A Potential Tool for Lymph Node Activity...

Area of Science:

• Radiology and Imaging
• Oncology
• Medical Physics

Background:

• Dual-energy CT (DECT) offers quantitative spectral data for tumor assessment.
• Normalized iodine concentration (nIC), effective atomic number (nZeff), electron density (nED), and extracellular volume (ECV) are key DECT parameters.
• Assessing lymph node activity is crucial for lymphoma diagnosis and treatment monitoring.

Purpose of the Study:

• To evaluate the diagnostic value of quantitative parameters from contrast-enhanced dual-layer spectral detector CT (SDCT) for detecting lymph node activity in lymphoma patients.
• To compare SDCT quantitative parameters with 18FDG-PET/CT findings.

Main Methods:

• Retrospective analysis of 55 lymphoma patients with 289 lymph nodes.
• Lymph node activity assessed using 18FDG-PET/CT and the Deauville five-point scale.
• Quantitative parameters (nIC, nZeff, nED, ECV) derived from SDCT spectral data were analyzed.

Main Results:

• Active lymph nodes demonstrated significantly higher nIC, nZeff, nED, and ECV values compared to inactive nodes (p < 0.001).
• Generalized linear mixed models confirmed significant fixed-effect parameters for nIC, nZeff, and ECV (p < 0.05).
• Area under the receiver operating characteristic curve (AUROC) values for diagnosing lymph node activity were 0.822 (nIC), 0.845 (nZeff), and 0.811 (ECV).

Conclusions:

• Quantitative SDCT parameters (nIC, nZeff, ECV) show significant potential for identifying lymph node activity in lymphoma.
• These parameters may serve as alternative imaging biomarkers to PET/CT.
• SDCT quantitative analysis could aid in guiding lymphoma treatment decisions.