Optimal Virtual Monochromatic Images for Evaluation of Normal Tissues and Head and Neck Cancer Using Dual-Energy CT

Area of Science:

• Radiology
• Medical Imaging
• Oncology

Background:

• Dual-energy CT (DECT) is underutilized for head and neck imaging.
• Optimal virtual monochromatic imaging (VMI) energies for head and neck evaluation remain undefined.

Purpose of the Study:

• To quantitatively determine optimal VMI energies for visualizing normal head and neck tissues, squamous cell carcinoma (SCC), and lymphadenopathy.
• To assess image quality and lesion conspicuity using DECT.

Main Methods:

• DECT scans from 40 patients (10 healthy, 30 with SCC) were analyzed at 40–140 keV.
• Signal-to-noise ratios (SNR) of muscles, glands, tumors, and lymph nodes were measured.
• Lesion attenuation and contrast-to-noise ratios (CNR) were evaluated for conspicuity.

Main Results:

• Optimal SNR for all tissues was achieved at 65 keV.
• Tumor attenuation and CNR were highest at 40 keV.
• Tumor-to-muscle attenuation difference was greatest at 40 keV.

Conclusions:

• 65 keV VMIs offer the best overall image quality for head and neck structures.
• 40 keV VMIs provide superior tumor conspicuity, particularly against muscle.
• A multiparametric approach using both 65 keV and 40 keV VMIs is recommended for comprehensive head and neck evaluation.