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Objective:To investigate the application value of dual-energy CT in the differential diagnosis of lung metastases and benign nodules in breast cancer.Methods:The data of 96 patients with pathology-confirmed breast cancer at the Fifth Affiliated Hospital of Wenzhou Medical University from March 2017 to June 2021 were analyzed retrospectively. All patients received dual-energy chest CT scans within 2 weeks before surgery. All 96 patients were female, aged 31-84 (56±12) years. A total of 207 pulmonary nodules from 96 patients were classified into 81 lung metastases and 126 benign nodules according to pathological findings. Conventional CT features [longest diameter, boundary, location and CT value difference between arterial and venous phases (ΔCT) of nodules] and dual-energy CT parameters [standardized iodine concentration (NIC), slope of energy spectrum (λ HU) and normalized effective atomic number (nZ eff) in arterial and venous phases] were analyzed and measured. The χ 2 test, independent samples t test and Kruskal-Wallis rank-sum test were used to analyze the differences of conventional CT features and dual-energy CT parameters between lung metastases and benign nodules. First, the least shrinkage and selection operator (LASSO) regression method was used to screen conventional CT features and dual-energy CT parameters, and then logistic regression analysis was performed to screen out independent risk factors for lung metastases. Receiver operating characteristic (ROC) curves were used to evaluate the efficacy of CT parameters alone and logistic model in differentiating lung metastases from benign lung nodules. Results:There were statistically significant differences between lung metastases and benign nodules in longest diameter, ?CT, NIC, λ HU and nZ eff in arterial and venous phases (all P<0.05). LASSO regression and binary logistic regression analysis showed that the venous phase λ HU (OR=59.413, 95%CI 14.233-248.002, P<0.001) and the venous phase nZ eff (OR=4.508, 95%CI 2.787-7.290, P<0.001) were independent risk factors for predicting lung metastases. Among them, the venous phase λ HU had the highest diagnostic efficiency, with an area under curve (AUC) of 0.794 and an accuracy of 74.88%. The AUC of the logistic model constructed by combining the venous phase λ HU and the venous phase nZ eff could reach 0.958, and the accuracy was improved to 92.27%, which was significantly higher than the efficacy of the two alone ( Z=6.02, 9.54, all P<0.001). Conclusion:Dual-energy CT has great application value in the identification of lung metastases and benign nodules in patients with breast cancer, especially when combined with venous phase λ HU and venous phase nZ eff, the diagnostic efficiency is further improved.
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Objective@#To explore and clarify the correlation between short-term aggressive intrasegmental recurrence (AIR) and functional magnetic resonance imaging after radiofrequency ablation of hepatocellular carcinoma (HCC).@*Methods@#A retrospective analysis of 1 262 patients with HCC who underwent radiofrequency ablation (RFA) in our hospital from January 2012 to June 2018, all patients were confirmed by pathology as HCC, of which 30 patients were found to have AIR during radiographic follow-up within 3 months after surgery, another 35 patients with disease progression who were controlled in a short period of time were randomly selected as the control group. All the enrolled patients underwent dynamic enhanced magnetic resonance imaging (DCE-MRI) and diffusion weighted imaging (DWI) scanning before surgery, and the differences in clinical data, lesion location, and functional magnetic resonance parameters between the two groups were compared, and their correlation with AIR after RFA was analyzed. Chi-square test, t test and Pearson test were used.@*Results@#The lesions in the AIR group were significantly more in the Ⅰand Ⅳsegments than that in the control group (P<0.05), and there was no significant difference in other liver segments (P>0.05). There was no significant difference in the lesion morphology between the two groups (P>0.05), and there was a significant difference in the early enhancement pattern of the lesions (P<0.05), and the early arterial enhancement rate and apparent diffusion coefficient (ADC) value of the AIR group were significantly lower than the control group (P<0.05). Further correlation analysis found that early enhancement of the arterial artery, early arterial enhancement rate, ADC value and lesion location were associated with AIR and were positively correlated, r values were 0.455, 0.633, 0.518, 0.375 and 0.287 (P<0.05).@*Conclusion@#The short-term AIR and functional imaging parameters (arterial early enhancement, early arterial enhancement rate, ADC value) and the liver segment (Ⅰ and Ⅳ) were highly correlated with radiofrequency ablation.
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Objective:To explore and clarify the correlation between short-term aggressive intrasegmental recurrence (AIR) and functional magnetic resonance imaging after radiofrequency ablation of hepatocellular carcinoma (HCC).Methods:A retrospective analysis of 1 262 patients with HCC who underwent radiofrequency ablation (RFA) in our hospital from January 2012 to June 2018, all patients were confirmed by pathology as HCC, of which 30 patients were found to have AIR during radiographic follow-up within 3 months after surgery, another 35 patients with disease progression who were controlled in a short period of time were randomly selected as the control group. All the enrolled patients underwent dynamic enhanced magnetic resonance imaging (DCE-MRI) and diffusion weighted imaging (DWI) scanning before surgery, and the differences in clinical data, lesion location, and functional magnetic resonance parameters between the two groups were compared, and their correlation with AIR after RFA was analyzed. Chi-square test, t test and Pearson test were used. Results:The lesions in the AIR group were significantly more in the Ⅰand Ⅳsegments than that in the control group ( P<0.05), and there was no significant difference in other liver segments ( P>0.05). There was no significant difference in the lesion morphology between the two groups ( P>0.05), and there was a significant difference in the early enhancement pattern of the lesions ( P<0.05), and the early arterial enhancement rate and apparent diffusion coefficient (ADC) value of the AIR group were significantly lower than the control group ( P<0.05). Further correlation analysis found that early enhancement of the arterial artery, early arterial enhancement rate, ADC value and lesion location were associated with AIR and were positively correlated, r values were 0.455, 0.633, 0.518, 0.375 and 0.287 ( P<0.05). Conclusion:The short-term AIR and functional imaging parameters (arterial early enhancement, early arterial enhancement rate, ADC value) and the liver segment (Ⅰ and Ⅳ) were highly correlated with radiofrequency ablation.
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Objective To explore the clinical value of the dual-low-dose with low tube voltage for head and neck CTA. Methods One hundred and sixty patients who were clinically suspected head and neck vascular disease underwent CTA procedure were propective selected, and whose body mass index (BMI) was also lower than 25 kg/m2. Forty cases were randomly selected as conventional group(120 kV,150 mAs, iodine 320 mg/ml), the other 120 cases were as the low dose group. The low dose group divided into three subgroups according to the random number table method, which were low iodine group (37 cases;120 kV,150 mAs, iodine 270 mg/ml), low tube voltage group (42 cases;100 kV,150 mAs, iodine 320 mg/ml) and low iodine and tube voltage group (41 cases;100 kV,150 mAs, iodine 270 mg/ml). The carotid bifurcated CT value, standard deviation (SD), signal-to-noise ratio (SNR), iodine intake and effective radiation dose (ED) of the four groups were recorded,all data undertook statistical analysis useing one-way ANOVA. Meanwhile, the subjective image quality score was applied to evaluate the image quality, and the differences among groups were compared by Wilcoxon signed ranks test. Results The image quality score were (2.85±0.19),(2.33 ± 0.34),(2.26 ± 0.32),(2.87 ± 0.22) in the four groups, and there was no statistical difference between groups(P>0.05).The carotid bifurcated CT value were respectively (380±30),(314±27),(514±52) and (425±28) HU in conventional, low iodine, low tube voltage and dual-low-dose groups, and the iodine intake were (18.85±2.10), (15.75±1.78), (18.53±1.98), (15.62±1.92) g, the ED of the four groups were (1.74±0.14), (1.73± 0.11), (1.32 ± 0.08) and (1.35 ± 0.09) mSv, the difference were all statistically significant (P<0.01). Furthermore, the iodine intake and the effective radiation dose in dual-low-dose group were significantly lower than the conventational group. Conclusions Head-and-neck CTA with dual-low-dose scan can provide same quality images as using 100 kV and high dose iodine contrast agent, and which also significantly reduced the ED and iodine intake greatly. Thus, this scanning program has great clinical value.
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Objective To explore the effect of chest circumference index adjusting tube voltage techniquey on image quality and radiation dose at coronary CTA. Methods One hundred and twenty consecutive patients [body mass index(BMI)90 cm, n=20). All patients were examined by coronary CTA. The patients in conventional group were performed using retrospective ECG-gating technology and reconstructed by filtered back projection algorithm. The tube voltage/tube current was 120 kV/1 000 mAs. Prospective ECG?gating technology and iterative algorithm reconstruction were used in low dose group. The tube voltages/currents were 80 kV/150 mAs, 100 kV/150 mAs, 120 kV/150 mAs in A, B, C group, respectively. Image quality was assessed by subjective evaluation (image quality score) and objective evaluation (signal?to?noise ratio).The effective radiation dose was calculated. Analyses of the differences between groups were compared with image quality, radiation dose by single factor variance and Wilcoxon signed ranks test.Results The image quality scores and signal?to?noise ratio of aorta were respectively (3.47 ± 0.38), (3.48 ± 0.27), (3.45 ± 0.32), (3.46±0.29) and (15.5±3.6), (15.8±3.6), (15.8±4.1), (16.2±3.9) in conventional, A, B and C groups, there was no statistical difference between the four groups (P=0.24, 0.43). The effective radiation dose of four groups were respectively (17.15 ± 3.25), (0.88 ± 0.02), (1.38 ± 0.05), (2.32 ± 0.04) mSv, the difference was statistically significant (P=0.02). The effective radiation dose of A, B, C group was significantly lower than that in the conventional group. Conclusion Chest circumference index adjusting tube voltages technology at coronary CT angiography can effectively reduce the effective radiation without compromise of image quality.
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Objective To explore the impact and value of 11C-MET PET/CT for high-grade glioma in making conformal radiotherapeutic planning compared with MRI.Methods From October 2011 to September 2013,11C-MET PET/CT and MRI were performed in 25 initial glioma cases and 9 recurrent cases.All 34 cases (19 males,15 females) were classified into initial group (n=17),initial surgery group (n=8) and recurrent group (n=9).GTV was outlined using PET/CT images combined with T1 weighted MRI images.Results 11 C-MET PET/CT optimized radiotherapy targets in 22 cases,including 7 initial cases,8 initial surgery cases and 7 recurrent cases.GTV was consistent with the volume of abnormally enhanced region on T1 weighted MRI (VMRI) in 10 initial cases,GTV＞VMRI in 5 cases,and GTV＜VMRI in 2 cases.GTV＜VMR1 in the initial surgery group.GTV was consistent with VMRI in 2 recurrent cases,GTV＞VMRI in 2 cases and GTV＜VMRI in 4 cases; 1 recurrent case's GTV located largely outside the VMRI.Conclusions There are some differences on locating the lesions of high-grade gliomas between 11C-MET PET/CT and MRI.Using 11CMET PET/CT in sketching radiotherapy target could significantly optimize the high grade glioma's radiotherapeutic planning,which may be more valuable in recurrent or operative cases.
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OBJECTIVE: To assess the effect of chest circumference-adapted scanning protocol on radiation exposure and image quality in patients undergoing prospective electrocardiogram (ECG)-triggered coronary CT angiography (CCTA). MATERIALS AND METHODS: One hundred-eighty-five consecutive patients, who had undergone prospective ECG triggering CCTA with a 128-slice CT, were included in the present study. Nipple-level chest circumference, body weight and height were measured before CT examinations. Patients were divided into four groups based on kV/ref.mAs = 100/200, 100/250, 120/200, and 120/250, when patient's chest circumference was 95.0 (n = 32), respectively. Image quality per-segment was independently assessed by two experienced observers. Image noise and attenuation were also measured. Signal-to-noise ratio (SNR) and contrast-to-noise ratio (CNR) were calculated. The effective radiation dose was calculated using CT dose volume index and the dose-length product. RESULTS: A significant correlation was observed between patients' chest circumference and body mass index (r = 0.762, p < 0.001). Chest circumference ranged from 74 to 105 cm, and the mean effective radiation dose was 1.9-3.8 mSv. Diagnostic image quality was obtained in 98.5% (2440/2478) of all evaluated coronary segments without any significant differences among the four groups (p = 0.650). No significant difference in image noise was observed among the four groups (p = 0.439), thus supporting the validity of the chest circumference-adapted scanning protocol. However, vessel attenuation, SNR and CNR were significantly higher in the 100 kV groups than in the 120 kV groups (p < 0.05). CONCLUSION: A measure of chest circumference can be used to adapt tube voltage and current for individualized radiation dose control, with resultant similar image noise and sustained diagnostic image quality.
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Adult , Aged , Female , Humans , Male , Middle Aged , Body Mass Index , Contrast Media , Electrocardiography , Heart/diagnostic imaging , Heart Rate , Prospective Studies , Radiation Dosage , Signal-To-Noise Ratio , Tomography, X-Ray Computed/methods , Waist CircumferenceABSTRACT
Membrane separation technology is a major branch in modern separation technology, which is widely applied in chemical, pharmaceutical and other industries. The purpose of this paper is to introduce principle and the application example of the membrane separation technology in medical devices, to analyse the problems existing in the current application, and to discuss the future development direction.