Investigating the effect of positron emitter of 18F-FDG dose and the body mass index on the detectability of liver cancer using PET-CT scanner

Mizar, Mahmoud; Abd Elqawy, Yasser; Ferreira, Goncalo; Ebaid, Yasser Y; Mohamed, Tarek Ahmed

doi:10.21608/ajnsa.2025.410135.1895

Investigating the effect of positron emitter of 18F-FDG dose and the body mass index on the detectability of liver cancer using PET-CT scanner

Document Type : Original Article

Authors

¹ Department of Physics, Faculty of Science, Fayoum University, Fayoum, Egypt. Department of Nuclear Medicine, Masria Scan Centers, Beni Suef &amp; Cairo, Egypt. Department of Nuclear Medicine, Burjeel Medical City, Abu-Dhabi, UAE.

² Department of Physics, Faculty of Science, Fayoum University, Fayoum, Egypt

³ Department of Nuclear Medicine, Burjeel Medical City, Abu-Dhabi, UAE

⁴ Physics Department, Faculty of Science, Fayoum University, Fayoum, EGYPT

⁵ Faculty of Science , Physics Department, Fayoum University, Fayoum, Egypt.

10.21608/ajnsa.2025.410135.1895

Abstract

Accurate image quality is critical for the effective detection of hepatic malignancies using PET/CT imaging. This study investigates the impact of body mass index (BMI) and fluorine-18 fluorodeoxyglucose (¹⁸F-FDG) dose on image quality, quantified through the signal-to-noise ratio (SNR), in liver cancer patients undergoing PET/CT scans. Seventy-five patients (32 males, 43 females) were categorized into normal weight, overweight, and obese groups based on BMI. PET/CT imaging was performed using a Discovery IQ scanner following intravenous administration of ¹⁸F-FDG, with two dosing protocols: 0.1 mCi/kg and a reduced dose of 0.05 mCi/kg. Acquisition times varied between 1 to 3 minutes per bed position, adjusted according to body habitus and dose.
The study demonstrated a clear inverse correlation between BMI and SNR, with obese patients showing the lowest SNR values. Patients receiving the lower 0.05 mCi/kg dose exhibited significantly reduced SNRs when imaged for only 1.5 minutes per bed. However, extending acquisition time to 3 minutes per bed restored image quality to levels comparable to those receiving 0.1 mCi/kg for 1.5 minutes. These findings highlight the effectiveness of dose-time compensation strategies in preserving image quality while minimizing radiation exposure.
In conclusion, PET/CT image quality is significantly influenced by BMI and injected dose. Optimization of scan duration based on patient-specific parameters can mitigate degradation in image clarity, supporting the feasibility of personalized imaging protocols to improve diagnostic outcomes and reduce radiation burden.

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