To investigate the prognostic value of right ventricular quantitative analysis system (RVQAS) combined with myocardial injury markers in patients with septic shock.

A total of 100 patients with septic shock admitted to the Department of Critical Care Medicine of the First Affiliated Hospital of Bengbu Medical University from May 2018 to May 2023 were selected and divided into survival group (n=76) and death group (n=24) according to the prognosis after 28 days, Quantitative medical parameters of the right ventricle of patients were recorded by RVQAS using bedside ultrasound. At the same time, the serum concentrations of myocardial injury markers on the day of admission were collected, and the above results were included in the statistical analysis.

Right ventricular end-diastolic volume (RVEDV), Right ventricular end-diastolic volume index (RVEDVI), Right ventricular end-systolic volume (RVESV) and Right ventricular end-systolic volume index (RVESVI) in the death group were higher than those in the survival group (P < 0.05). right ventricular ejection fraction (RVEF), right ventricular cardiac output, right ventricular cardiac index, right ventricular stroke volume and right ventricular stroke volume index were lower in the death group than in the survival group (P < 0.05). The serum concentrations of creatine kinase (CK), creatine kinase isoenzyme and cardiac troponin Ⅰ (cTnⅠ) in the death group were higher than those in the survival group (P < 0.05). Spearman correlation analysis showed that the death of patients was positively correlated with RVEDV, RVEDVI, RVESV, RVESVI, CK and cTnI, and negatively correlated with RVEF (P < 0.05). The ROC curve showed that the area under the curve of RVESVI alone was 0.948, and the area under the curve of RVESVI combined with CK was 0.999 in the diagnosis of septic shock, and the predictive value of RVESVI for death was the highest.

RVQAS measurement of right ventricular function can provide more reference information for the timely and effective treatment of patients with septic shock. RVESVI combined with CK has the highest predictive value for the death of patients, and should be used in clinical practice earlier to bring greater benefits for the early diagnosis and treatment of patients.

To assess the feasibility and imaging characteristics of clinical 1.5T MRI in visualizing cerebral lesions at different time points (6 h, 3 d, 5 d, 7 d, 14 d) in an acute ischemic stroke rat model.

Ten healthy male Sprague-Dawley rats, aged 10-12 weeks, were randomly selected and subjected to permanent middle cerebral artery occlusion via the filament method to induce ischemic stroke. MRI scans, including T1WI, T2WI, T2 FLAIR, and DWI, were conducted using a 1.5T clinical MRI scanner at the specified time intervals (6 h, 3 d, 5 d, 7 d, 14 d), capturing morphological and signal intensity changes across infarction stages in the rats.

The DWI sequence obtained from the 1.5T MRI scanner facilitated diagnosis of ultra-acute cerebral infarction in rats, effectively delineating infarction extent and scope. Infarct lesions in the model rats exhibited distinct imaging changes across stages, with signal intensity and morphology alterations becoming apparent in conventional MRI sequences as the infarction progressed.

The clinical 1.5T MRI technique proves effective in monitoring time-dependent dynamic changes in cerebral lesions in the ischemic stroke rat model. DWI, in particular, exhibits outstanding diagnostic capacity in ultra-acute infarction, thus providing valuable imaging support for advanced clinical research and therapeutic planning.

To explore the effectiveness and feasibility of the deep convolutional neural network model, based on V-Net, for automatic recognition and segmentation of the pancreas and its tumors.

A retrospective analysis was conducted on the enhanced CT imaging data of 186 patients with pathologically confirmed pancreatic cancer who visited First People's Hospital Affiliated to Shanghai Jiaotong University Medical College from May 2012 to November 2019. After screening, a total of 108 cases of pancreatic cancer were included, and 37 cases of normal pancreas during the same period were randomly collected for comparison, resulting in a final dataset of 145 cases for this study. This paper employed a five-fold cross-validation method and manually annotated regions of interest on arterial phase CT images, including the pancreatic head and neck, body and tail, and tumors. The model's ability to identify pancreatic tumors was evaluated by calculating metrics such as sensitivity, specificity, F1 score, and Kappa consistency verification was performed. Dice coefficient was used to quantitatively assess the model's segmentation capability, and visual results were obtained for further evaluation.

The V-Net based model for identifying pancreatic tumors has a sensitivity of 0.852, a specificity of 1.000, a positive predictive value of 1.000, a negative predictive value of 0.698, and an F1 score as high as 0.920. The consistency verification shows that the Kappa coefficient is 0.746 (P < 0.05). In the segmentation task, the mean Dice for pancreatic tumors, pancreatic body and tail, pancreatic head and neck were 0.722±0.290, 0.602±0.175, 0.567±0.200, respectively.

We constructed a deep convolutional network model based on V-Net, which successfully achieved automatic identification and segmentation of the pancreas and tumors. Our findings demonstrated the effectiveness and feasibility of this approach, offering robust support for the exploration of artificial intelligence applications in the field of pancreatic tumor research.

To explore the relationship between enlarged perivascular spaces in the basal ganglia (BG-EPVS) and sleep structure in patients with cerebral small-vessel disease (CSVD) by polysomnography.

Ninety-five CSVD patients who were hospitalized in the Department of Neurology of the Third Affiliated Hospital of Southern Medical University from February 2023 to June 2024 completed 3.0T magnetic resonance imaging were included. The perivascular spaces in the basal ganglia were evaluated and graded by visual quantitative assessment method, and the patients were divided into none to mild BG-EPVS group (n=45) and moderate to severe BG-EPVS group (n=50) according to the grading. All patients underwent overnight polysomnography monitoring and relevant data were recorded. The general clinical data and polysomnography parameters of the two groups were compared.

There was no statistically significant difference in gender, BMI, smoking and drinking history between the two groups (P>0.05). Compared with the none to mild BG-EPVS group, patients in the moderate to severe BG-EPVS group were older, and the proportion of lacunar infarction and renal insufficiency was higher (P < 0.05). Comparison of sleep parameters between the two groups showed that compared with the none to mild BG-EPVS group, the duration of REM sleep and the percentage of REM sleep in total sleep time were decreased in the moderate to severe BG-EPVS group (P < 0.05). There was no statistically significant difference in sleep process parameters, sleep quality parameters and other sleep structure parameters between the two groups (P>0.05). Spearman correlation analysis showed that the duration of REM sleep and the percentage of REM sleep in total sleep time were negatively correlated with the BG-EPVS grade (P < 0.05), and there was no significant correlation between the duration and percentage of sleep in NREM sleep stages and the BG-EPVS grade (P>0.05). Multivariate logistic regression analysis found that increased age, lacunar infarction, and decreased percentage of REM sleep in total sleep time were independent risk factors for moderate to severe enlargement of perivascular spaces in the basal ganglia (P < 0.05).

Patients with higher age, lacunar infarction, and decreased percentage of REM sleep in total sleep time are more likely to develop BG-EPVS, suggesting that adjusting sleep structure, especially improving the quality of REM sleep, may play an important role in preventing BG-EPVS.

To observe the performance of sleep disorders in insomnia patients of different ages, and to compare the volume differences of thalamic subregions in insomnia patients of all ages based on MRI acquisition of nuclear magnetic dataof the brain, and to explore the correlation between sleep disorders and the volume of thalamic subregions.

Sixty patients with primary insomnia who attended the Rehabilitation Hospital of Fujian University of Traditional Chinese Medicine from July 2023 to June 2024 were categorized by age into young group (18-44 years old), middle-aged group (45-59 years old), and old-aged group (60-75 years old), 20 cases per group. The Pittsburgh sleep quality index was used to assess the sleep quality and degree of insomnia of the patients in each group, and the Siemens 3.0T Prisma magnetic imaging system was used to collect 3D T1 structural image data of the patients, to automatically segment and measure the volumes of the thalamus and six subregions, and to analyze and compare the thalamic subregions of the patients in each group. We analyzed and compared the volume differences of the thalamic subregions in each group of patients, and explored the correlation between the patients' sleep disorders and the volume of the thalamic subregions using partial correlation analysis.

The Pittsburgh sleep quality index total score, sleep latency, habitual sleep efficiency and insomnia degree grading differed among patients with primary insomnia of different ages (P < 0.05), and significant intergroup differences existed among the medial thalamus, lateral thalamus, posterior thalamus and thalamus total volume (P < 0.05). Moreover, the results of the partial correlation analysis showed that the sleep efficiency was negatively correlated to the volume of posterior thalamus (r=-0.274, P=0.038).

Primary insomnia patients of different age groups have different manifestations of sleep disorders. MRI was used to collect brain nuclear magnetic data from insomnia patients, and the analysis of the MRI data revealed that it might be related to the atrophy of grey matter structures in some brain regions of the thalamic system, which provides an important reference for individualized treatment of the patients and improvement of clinical prognosis.

To evaluate the feasibility of using deep learning reconstruction (DLIR) for pulmonary nodule assessment under ultra-low dose CT (ULDCT) scanning.

A total of 142 patients who underwent CT scans for pulmonary nodules re-examination included. All patients were examined by both standard-dose CT (SDCT) and ULDCT. SDCT images were reconstructed with adaptive statistical iterative reconstruction-V 40% (ASIR-V40%), ULDCT images were reconstructed with ASIR-V40% and DLIR-H, respectively. A total of three sets of images were obtained (Group A, group B, group C). The radiation dose of both scanning modes and the number of lung nodules were recorded manually. The CT values and noise values (SD) of lung tissue, aorta and muscle were measured in 3 groups images, and the signal-to-noise ratio (SNR) was calculated for each tissue.The malignant signs of lung nodules in the three groups were scored by double-blind method. Using the pathological diagnosis as the gold standard, the diagnostic efficacy of ULDCT and SDCT examination on the malignant signs (burr, lobular, pleural traction sign, vacuole or void, vascular perforation) of pulmonary nodules was analyzed by comparison. Statistical analysis was performed on the quantitative indicators and subjective scores of these three sets of images.

The radiation dose of ULDCT was reduced by about 92.7% compared with SDCT, and the difference was statistically significant (P < 0.05).The SD values of lung tissue, aorta and muscle in group C were lower than those in group B, and the SNR was higher than that in group B (P < 0.05), and the ability to display malignant signs of nodules were better than those in group B, and there was no statistical difference between group C and group A (P>0.05). The number of pulmonary nodules detected in the three groups was 187, 179 and 187, respectively. Compared with the pathological results, the efficacy of group A and group C in diagnosing malignant pulmonary nodules was higher than that of group B, and the difference was statistically significant (P < 0.05).

Ultra-low-dose chest CT combined with deep learning reconstruction can obtain image quality comparable to ASIR-V40% of SDCT, and show good detection and signs of nodules, which can be used for clinical evaluation of pulmonary nodules.

To preliminarily investigate the application value of multi-modal MRI high-resolution scanning with rectal water instillation in the diagnosis of anal fistula.

Patients who were diagnosed with anal fistula in our hospital from October 2022 to January 2024 were selected for MR examinations. More specifically, following routine MRI sequence scanning, these patients received the same sequence scanning and dynamic contrast-enhanced MRI (DCE-MRI) examinations after rectal water instillation. In this foundation, this research further compares the clarity of fistulas as well as the relationship between fistulas and adjacent sphincters in each conventional sequence, thereby identifying the optimal sequence. Furthermore, this research compares the changes in fistula length, the maximum diameter of fistulas, the internal orifice diameter of fistulas and the detection rate of fistula before and after rectal water instillation in the optimal sequence.

A total of 67 fistulas were observed in 41 patients with anal fistula confirmed by surgery and pathology. Specifically, T1WI, T2WI, three-dimensional spin echo with short time inversion recovery (3D-STIR-TSE) sequences before rectal water instillation as well as DCE-MRI sequence after rectal water instillation exhibited significant differences in the clarity of fistulas and the relationship between fistulas and adjacent sphincters (P < 0.05), among which 3D-STIR-TSE sequence performed best. Further analysis of 3D-STIR-TSE sequence demonstrated that there were statistical differences in the length, maximum diameter, and internal orifice diameter of fistulas before and after rectal water instillation (P < 0.05). Moreover, regarding the contrast of the clarity of fistulas before and after rectal water instillation, the detection rate of fistulas before rectal water instillation was 89.55%, whereas that after rectal water instillation increased to 98.51%. The difference between them was statistically significant (P=0.04).

3D-STIR-TSE sequence achieves the optimal performance in the diagnosis and examination of anal fistula by multi-modal MRI. The easy-operated multi-modal MRI examination with rectal water instillation, being a pivotal supplement to routine MRI examinations, is capable of improving the diagnostic ability for fistulas.

To investigate the diagnostic effectiveness of digital breast tomosynthesis (DBT), full-field digital mammography (FFDM), ultrasound and MRI in the diagnosis of dense breast lesions.

A retrospective analysis was conducted by two experienced and inexperienced radiologists on 223 dense breast lesions that underwent both FFDM and DBT examinations, as well as a retrospective analysis on 97 dense breast lesions that underwent both FFDM, DBT, ultrasound, and MRI examinations. The dense breast lesions were diagnosed as benign (BI-RADS grade 4a and below) or malignant (BIRADS grade 4b and above), based on the images of FFDM, DBT, ultrasound and MRI, respectively. All patients underwent surgery to get a pathological diagnosis. Kappa consistency tests and ROC curve were used to compare the efficacy of high- and low-experience radiologists, as well as FFDM, DBT, FFDM+DBT, ultrasound, and MRI in the diagnosis of dense breast lesions.

In the comparison between senior and junior radiologists using FFDM and DBT, the senior radiologist use DBT to diagnose dense breast lesions had a high degree of consistency with the pathological results (Kappa=0.712), while the junior radiologist use FFDM diagnosis efficiency was lower than that of the junior radiologist use DBT and the senior radiologist use FFDM and DBT (AUC=0.610, 0.808, 0.652, 0.855). In the comparisons between FFDM, DBT, FFDM+DBT, ultrasound and MRI, the diagnostic results of DBT, FFDM+DBT and MR examinations had high consistency with the pathological gold standard, and the consistency increased (Kappa=0.688, 0.707, 0.792). In all dense breast lesions, the diagnostic efficacy of FFDM, FFDM+ DBT and MRI increased gradually (AUC=0.690, 0.815, 0.888).

Both junior and senior radiologists can improve their diagnostic efficiency by using the DBT examination method, and the improvement in diagnostic efficiency for junior radiologists is more significant. Radiologists can significantly improve the diagnostic efficiency of mammography by using the DBT technology, and the diagnostic efficiency is equivalent to that of MR. The pathological consistency of DBT is slightly lower than that of FFDM+DBT, but the diagnostic efficiency is equivalent.

To explore the characteristics of CT enterography (CTE) and their evaluation value for disease severity in patients with Crohn's disease (CD).

A total of 82 patients with CD admitted to the hospital were retrospectively enrolled from January 2020 to April 2024. According to CD activity index (CDAI), they were divided into remission group (n= 34, CDAI < 150 points) and active group (n=48, CDAI≥150 points). All patients underwent CTE. CTE characteristics were compared between the two groups. The evaluation value of CTE characteristics for disease severity in CD patients was analyzed by ROC curves.

There were differences in enhancement mode, enlargement of mesenteric lymph nodes, increase of mesenteric fat density, tooth comb sign and cellulitis between the two groups (P < 0.05). The thickness of intestinal walls, CT values in arterial and venous phases in remission group were lower than those in active group (P < 0.05). The results of ROC curves analysis showed that area under the curve values of intestinal wall thickness, arterial CT value, venous CT value and combined detection (parallel mode) for evaluating disease severity in CD patients were 0.857, 0.775, 0.808 and 0.920, respectively (P < 0.05).

CTE can fully and clearly display intestinal wall and parenteral manifestations in CD patients. CTE quantitative parameters (thickness of intestinal walls, CT values in arterial and venous phases) are beneficial to evaluate disease severity in CD patients.

To explore the clinical value of ^99mTcO₄^- ectopic gastric mucosa imaging in the diagnosis of Meckel's diverticulum in children.

A retrospective analysis was conducted on thirty-nine children with clinical suspicion of Meckel's diverticulum who were admitted to the Second Hospital of Lanzhou University from January 2017 to January 2022 due to symptoms such as hematochezia and intestinal obstruction. Basic information, blood routine, ^99mTcO₄^- ectopic gastric mucosa imaging, abdominal ultrasound and surgical pathological results were included.

Among the thirty-nine children, twenty-five were confirmed to have Meckel's diverticulum through surgery. The diagnostic sensitivity of ^99mTcO₄^- ectopic gastric mucosa imaging was 64.00%, the specificity was 92.31%, the positive predictive value was 94.12%, and the diagnostic accuracy was 71.79%. The hemoglobin and red blood cell in the Meckel's diverticulum group were significantly lower than those in the non-Meckel's diverticulum group(P < 0.05). The Meckel's diverticulum group was divided into the true positive group (n=16) and the false negative group (n=9) based on the results of ^99mTcO₄^- ectopic gastric mucosa imaging before surgery. The hemoglobin, red blood cell and white blood cell counts in the true positive group were significantly lower than those in the false negative group; the maximum diameter of the lesion in the true positive group was significantly larger than that in the false negative group; pathologically confirmed that all patients in the true positive group had ectopic gastric mucosa, and 6 patients in the false negative group had ectopic gastric mucosa. There was a statistically significant difference in the presence of ectopic gastric mucosa tissue between the two groups (P < 0.05).

^99mTcO₄^- ectopic gastric mucosal imaging holds significant diagnostic value for Meckel's diverticulum in children, although its accuracy is influenced by various factors.

To investigate the effect of low contrast agent dosage and low flow rate combined with the new virtual single energy imaging (Mono+) technology on the degree of vascular enhancement and image quality in aortic CT images.

A total of 120 patients with suspected aortic dissection who underwent CTA examination in our hospital from December 2023 to April 2024 were prospectively collected, and were randomly divided into routine group and experimental group, with 60 cases each group. The conventional group used conventional scanning; The experimental group used dualenergy scanning. The CT value and noise value (SD) of the aorta and its branches were measured, and the signal-to-noise ratio and contrast-to-noise ratio of the aorta and its branches were calculated using the SD value of the posterior muscle group of the T12 layer as the reference noise. Mono+ technique was used to obtain seven sets of single energy images of 40, 45, 50, 55, 60, 65 and 70 keV, respectively. The objective and subjective evaluation criteria of these single energy images were analyzed, and the dose of contrast agent, injection rate, radiation dose and image quality were compared and evaluated.

In the 7 groups of single energy, CT values, signal-to-noise ratio and contrast-to-noise ratio of aorta and its branches gradually decreased with the increase of voltage (P < 0.05). The subjective score of 60 keV group was the highest (P < 0.05). Compared with the conventional group, the dosage of contrast agent in the experimental group was reduced by 18%. The rate was reduced to 2.54± 0.09 mL/s (P < 0.05). In addition, CT volume dose index, dose-length product and effective dose in the experimental group were reduced by about 50% compared with the control group, and the difference was statistically significant (P < 0.05).

In aortic CTA imaging, the combination of low contrast agent dosage and low flow rate with Mono+ technology is feasible. Compared with traditional imaging methods, this method can not only meet the needs of clinical image quality, but also significantly reduce the use of contrast agent, injection rate and radiation dose.

To evaluate the utility of a combined model integrating clinical characteristics and plain CT imaging features in predicting the invasiveness of primary lung adenocarcinoma with diameters less than 30 mm.

A retrospective analysis was conducted on 107 patients with pulmonary nodules who underwent preoperative chest CT scans at our hospital from January 2020 to December 2023. Patients were categorized into four groups based on pathological diagnosis: atypical adenomatous hyperplasia, adenocarcinoma in situ, minimally invasive adenocarcinoma, and invasive adenocarcinoma. Among them, 73 patients with atypical adenomatous hyperplasia, adenocarcinoma in situ, and minimally invasive adenocarcinoma formed the non-invasive group (including 22 males, mean age 49.73±13.92), while 34 patients with invasive adenocarcinoma constituted the invasive group (including 14 males, mean age 57.53±12.00). Clinical data including age, gender, and imaging details were collected and compared between the two groups. Univariate and multivariate analyses were performed to identify independent predictors of lung adenocarcinoma invasiveness, leading to the development of a predictive model. Model performance was assessed using ROC curve analysis.

Significant differences were observed between the two groups in terms of gender and age (P < 0.05). Various CT imaging features such as nodule type, location, average diameter, shape, margin, spiculation, pleural indentation, presence of emphysema, air bronchogram, vacuole sign, and vascular type exhibited statistically significant differences between the groups (P < 0.05). Average nodule diameter and vascular type were identified as independent predictors of lung adenocarcinoma invasiveness (P < 0.05). The ROC curve analysis showed an AUC of 0.891 (95%CI: 0.816-0.956) for the combined model in diagnosing lung adenocarcinoma invasiveness. Using the optimal Youden index of 0.514, the cutoff value for average nodule diameter was determined to be 9.75 mm, with a sensitivity of 0.706 and specificity of 0.808.

Plain CT imaging features of pulmonary nodules play a crucial role in preoperatively assessing the invasiveness of lung adenocarcinoma. Average nodule diameter and vascular type independently predict lung adenocarcinoma invasiveness.

To explore the application of optimal monochromatic images using dual-energy spectral CT in low-dose renal venography.

Forty patients for renal CT venography in Affiliated Hospital of Shaanxi University of Chinese Medicine from May 2022 to October 2023 were recruited and randomly divided into group A and group B, with twenty patients each. Group A was scanned with conventional 120 kVp with contrast agent dose of 600 mgI/kg and reconstructed with 40% ASIR. Group B was scanned with dual-energy spectral CT mode with contrast agent dose of 450 mgI/kg and reconstructed with 40% ASIR and the optimal monochromatic images. The CT values and standard deviation of the left renal vein, right renal vein and erector muscle at the same level were measured to calculate the signal-to-noise-ratio and contrast-to-noise ratio values for the renal veins. The image quality was subjectively scored by two experienced radiologists blindly using a 5-point system. The CT volumetric dose index and dose length product were recorded for both groups and the effective radiation dose was calculated.

There were no significant difference in general data between the two groups (P>0.05). The contrast agent dose and effective radiation dose in group B were decreased by 26.2% and 23.5% respectively compared with group A (P<0.05). The CT values, signal-to-noise-ratio values and contrast-to-noise ratio values of group B were significantly higher than those of group A (P<0.05), and the standard deviation values was significantly lower than that of group A (P<0.05). The subjective score of group B was significantly higher than that of group A and the differences showed significant differences (P<0.05).

Spectral CT imaging with optimal monochromatic images can significantly reduce contrast agent dose and radiation dose in renal venography, and provide better image quality than the conventional 120 kVp protocol.

To investigate the correlation between ¹⁸F-FDG PET/CT metabolic parameters, serum tumor markers and clinicopathological characteristics of patients with gastric cancer.

The ¹⁸F-FDG PET/CT imaging data and clinical data of 41 patients with pathologically confirmed gastric cancer who underwent ¹⁸F-FDG PET/CT in the Department of Nuclear Medicine of our hospital from January 2019 to September 2023 were retrospectively analyzed. Standardized uptake value (SUV)_max, SUV_peak, SUV_mean, maximum standard intake value for fat removal (SUL), tumor metabolic volume (MTV) and total glycolysis (TLG) of primary gastric cancer were measured, and the expression levels of serum tumor markers were recorded. The differences of metabolic parameters and tumor markers among different clinical stages, tumor tissue differentiation and Lauren classification groups were compared, and the correlation between metabolic parameters, tumor markers and clinicopathological characteristics was analyzed.

There were significant differences in SUV_max, SUV_peak, SUV_mean, SUL, TLG, MTV, and the positive detection values of carcinoembryonic antigen (CEA), carbohydrate antigen (CA)19-9 and CA72-4 in different clinical stages (P<0.05). There was a significant difference in MTV among different tumor differentiation (P<0.05), while there was no significant difference in SUV_max, SUV_peak, SUV_mean, SUL, TLG and the positive detection values of CEA, CA19-9 and CA72-4 (P>0.05). There was no significant difference in each index between different Lauren types (P>0.05). The accuracy of SUV_max, SUV_peak, SUV_mean, SUL, TLG, MTV combined with CEA, CA19-9, CA72-4 in predicting clinical stage reached 92.7%.

¹⁸F-FDG PET/CT metabolic parameters combined with serum tumor markers can help to reflect some of the clinicopathological characteristics of tumors, which is of great significance for the development of clinical individualized treatment plan.

To explore the application effect of low dosage and low concentration of contrast agent combined with different weights of ASIR-Ⅴ in portal vein spectroscopy CT examination.

We collected 84 patients who underwent portal vein CT enhancement examination at the First Affiliated Hospital of Bengbu Medical University from November 2023 to April 2024 and then randomly divided into A and B group, with 42 cases in each. In group A, the patients underwent energy spectrum CT combined with 60% adaptive statistical iterative reconstruction-Ⅴ (ASIR-Ⅴ) scanning. The iodine contrast concentration used was 320 mgI/mL, and the contrast agent dosage was calculated as 1.2 mL/kg. Additionally, single energy images ranging from 40 to 80 keV were extracted from the original data at 10 keV intervals. The portal vein images of 20 subgroups were reconstructed using ASIR-Ⅴ with increments of 20% (ranging from 20%-80%). Group B underwent a CT scan with conventional CT combined with a 0% ASIR-Ⅴ preposition, iodine contrast concentration of 350 mgI/mL, and a contrast agent dosage calculated at 1.5 mL/kg. Images with 120 kV were automatically output with a 0% ASIR-Ⅴ preposition. The CT values, noise (SD), signal-to-noise ratio (SNR), and contrast-to-noise ratio (CNR) of the largest portal vein main layer, as well as the liver parenchyma and erector spinal muscle of the same layer, were measured and calculated in both groups. Subsequently, the imaging diagnostic physician conducted a subjective assessment of the image quality. Objective image quality indicators and the amount of contrast agent were analyzed using independent sample t-test and Kruskal-Wallis H test, while subjective image indicators were assessed using the Kappa consistency test.

The increase in post-ASIR-Ⅴ weight resulted in a significant decrease in image noise (P<0.001) and an increase in both SNR and CNR. In group A, the background SD of 60keV, with 60% ASIR-Ⅴ preposition and 60% ASIR-Ⅴ postposition, was 26.06±3.95 HU, significantly higher than that of the control group (18.80±2.39 HU) (P<0.001). Additionally, SNR and CNR were significantly higher than those in group B (P<0.001). The iodine intake and the effective radiation dose in group A were significantly lower than those in group B (P<0.001). Although the subjective score of group B was slightly higher than that of group A, the difference was not found to be statistically significant.

The quality of portal vein images obtained through energy spectrum CT using low-dose and lowconcentration contrast agents, combined with anterior and posterior ASIR-Ⅴ, is comparable to those obtained through conventional CT enhancement. This approach has the potential to significantly reduce radiation dose and iodine intake, making it suitable for clinical application.