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Background: During computed tomography (CT) examinations, the presence of radiation material undoubtedly has a certain impact on patients, particularly children, who are more susceptible to radiation. Consequently, finding ways to minimize radiation dosage and mitigate radiation-related risks while enhancing the quality and accuracy of CT scans has become a crucial concern for medical professionals in CT equipment manufacturing companies and radiology departments to contemplate. Objectives: This study aimed to explore the feasibility of low dose and low contrast medium combined with low flow rate scanning in CT angiography (CTA) of children's liver. Patients and Methods: A total of 59 children who visited our department for liver vascular CT scans between April 2021 and December 2022 were prospectively selected and randomly divided into 2 groups: the experimental group and the control group. The experimental group consisted of 28 children who received an injection of 80 kV, automatic tube current, low contrast dose (1.5 mL/kg), and low flow rate of 20 s. The control group included 31 children who were injected with 100 kV, automatic tube current, contrast agent dose (2 mL/kg), and flow rate of 16 s. The objective and subjective image quality, radiation dose, and iodine intake in the arterial, portal, and venous phases were compared between the 2 groups. Results: During the arterial, portal, and venous phases, the experimental group exhibited lower signal-to-noise ratio (SNR) and contrast-to-noise ratio (CNR) compared to the control group (P < 0.05). However, there was no significant difference in subjective quality scores between the 2 groups (P> 0.05). The effective dose (ED), volume CT dose index (CTDIvol), and dose-length product (DLP) of the experimental group were lower than those of the control group (P< 0.05). Additionally, the iodine intake in the experimental group was lower than that in the control group (P < 0.05). Conclusion: In the examination of hepatic vascular CTA in children, the use of a 3-low scanning technique can effectively decrease radiation and contrast agents while ensuring sufficient image quality for accurate clinical diagnosis. [ABSTRACT FROM AUTHOR]

Abstract: Zinc smelting and chlor-alkali production are major sources of Hg contamination to the environment, potentially leading to serious impacts on the health of the local population. Huludao, NE China has been heavily contaminated by Hg due to long-term Zn smelting and chlor-alkali production. The aim of this work was to determine Hg accumulation in the aquatic and terrestrial environment, as well as in the human population of Huludao. The investigation included: (a) Hg accumulation in sediments, Spirogyra algae, crucian carp and shrimp, (b) Hg distribution in soil, vegetables and corn, and (c) assessment of potential health effects of Hg exposure associated with total Hg (T-Hg) concentrations in human hair. Measured T-Hg concentrations in sediments of Wuli River ranged from 0.15 to 15.4mgkg−1, with the maximum Hg concentration in sediment exceeding the background levels in Liaoning Province by 438 times. The maximum T-Hg levels in Spirogyra, crucian carp and shrimp were 13.6, 0.36, and 0.44mgkg−1, respectively. Total-Hg concentrations in hair of the human population varied from 0.05 to 3.25mgkg−1 (average 0.43mgkg−1). However, the frequency of paraesthesia to most inhabitants in Huludao was estimated to be lower than 5%, with only one person rated at 50%. The results indicated minimal adverse health effects of Hg exposure to the inhabitants of Huludao, despite the serious Hg contamination of the environment. [ABSTRACT FROM AUTHOR]