Analysis of radiation dose reduction in oncological followup cases by using dual energy CT

Background: Concern about radiation effects is particularly significant for cancer patients who require frequent imaging for follow-up assessments. Computed tomography (CT) is a key tool in the diagnosis and monitoring of cancer. Purpose: To demonstrate radiation dose reduction using dual-energy CT (DECT) compared with single-energy CT (SECT) in the follow-up of cancer patients. Patients and methods: This retrospective cohort study, conducted at the Fondazione INT IRCCS G. Pascale in Naples, Italy, evaluated the effectiveness of spectral dual-energy CT in reducing radiation doses during follow-up compared with conventional CT. 80 patients undergoing oncology follow-up for different cancers underwent both DESCT and conventional CT scans. A quantitative approach focused on the analysis of radiation dose measurements (CTDI and DLP), while qualitative assessments evaluated improvements in image quality. Statistical analysis was performed using SPSS version 27.0, with paired t-tests comparing radiation doses between the two methods to determine significant differences. Results: DECT showed statistically significant reductions in radiation exposure: mean CTDI (SECT: 9.3 ± 1.1 mGy vs DECT: 5.7 ± 1.0 mGy, p < 0.001), DLP (SECT: 875.3 ± 112.5 mGy·cm vs DECT: 621.0 ± 95.7 mGy·cm, p < 0.001), ED (SECT: 12.3 ± 2.0 mSv vs DECT: 8.0 ± 1.5 mSv, p < 0.001). SNR and CNR were also improved. No statistically significant gender-based differences were found. Conclusion: Dual-energy spectral CT significantly reduces radiation dose compared to conventional CT, with substantial decreases in CT dose index (CTDI), dose-length product (DLP), and effective dose.