Comparing the image quality of a mobile flat-panel computed tomography and a multidetector computed tomography: a...

Area of Science:

• Medical Imaging
• Radiology
• Computed Tomography

Background:

• Advancements in medical imaging technology are crucial for accurate diagnosis.
• Comparing novel imaging modalities with established ones is essential for understanding their clinical utility.
• Flat-panel computed tomography (FPCT) offers potential for mobile and extremity imaging applications.

Purpose of the Study:

• To compare the image quality of a compact mobile FPCT with a 320-row multidetector computed tomography (MDCT) system.
• To evaluate performance at equivalent radiation doses for both imaging modalities.
• To assess parameters including homogeneity, geometric distortion, artifacts, Hounsfield value accuracy, contrast, and spatial resolution.

Main Methods:

• FPCT imaging was performed using default settings.
• Equivalent radiation doses for MDCT were calculated using Monte Carlo simulations, validated by dose measurements.
• Image quality was assessed using various phantoms, evaluating homogeneity, geometric distortion, artifacts, Hounsfield values, contrast, and spatial resolution.
• Statistical analysis was conducted using Whitney-Mann U Test and Spearman ρ.

Main Results:

• MDCT demonstrated superior homogeneity (0.5% vs. 2.5% for FPCT) and more accurate Hounsfield values.
• Contrast-to-noise ratios were significantly higher in MDCT (P ≤ 0.001).
• FPCT exhibited higher spatial resolution (1.7 lp/mm in z-axis) compared to MDCT (less than 1 lp/mm in z-axis).
• Artifacts differed: FPCT was more prone to artifacts around thick Kirschner wires (2 mm), while MDCT showed more artifacts around thin wires (0.8 mm).

Conclusions:

• MDCT provides better accuracy, homogeneity, and contrast resolution for extremity imaging compared to FPCT at equivalent radiation doses.
• FPCT offers superior spatial resolution, particularly in the z-axis.
• Both modalities have distinct artifact profiles depending on the size of metallic implants like Kirschner wires.