Image quality and radiation dose optimization in CT pulmonary angiography using 120, 100, and 80 kV protocols for pulmonary thromboembolism diagnosis
Year: 2026
Type: article
Study design: Observational Study
Abstract: Background: Computed tomography pulmonary angiography (CTPA) is the standard imaging modality for diagnosing pulmonary thromboembolism (PTE). Lowering tube potential enhances iodine attenuation but may affect image noise. This retrospective study evaluated quantitative image quality, subjective ratings, and radiation dose across 120, 100, and 80 kV CTPA protocols on a dual-source CT scanner. Methods: Ninety adult patients (n=30 per protocol) undergoing clinically indicated CTPA were evaluated across three tube potential settings (120, 100, and 80 kV). Quantitative parameters pulmonary artery attenuation [Hounsfield unit (HU)], image noise [standard deviation (SD)], signal-to-noise ratio (SNR), contrast-to-noise ratio (CNR), and size-specific dose estimates (SSDE)-were evaluated. Three cardiothoracic radiologists performed blinded qualitative assessments using a 5-point Likert scale. Radiation dose metrics [volumetric computed tomography dose index (CTDIvol), dose-length product (DLP), and estimated effective dose] were recorded. Results: 20.23±4.1 HU, P=0.26). SNR and CNR were significantly higher at 80 kV (25.93±2.6 and 25.20±3.4) compared with 120 kV (18.19±4.8 and 9.31±2.1, P<0.001). Effective dose decreased significantly by 46.4% from 3.34±0.67 mSv (120 kV) to 1.79±0.35 mSv (80 kV) (P<0.001). Qualitative scores for overall image quality, vascular enhancement, and motion artifacts showed no significant differences across protocols (P>0.05). Conclusions: Lowering tube potential to 80 kV in CTPA significantly increases vascular attenuation, SNR, and CNR while offering substantial radiation dose savings and maintaining subjective image quality scores. These findings support the feasibility of an 80-kV protocol for radiation dose optimization in CTPA.
Language: English
Topic: Radiation Dose and Imaging
Subfield: Radiology, Nuclear Medicine and Imaging
Field: Medicine
Domain: Health Sciences
Open Access status: diamond
OpenAlex ID: W7223219927