Objective This study aimed to explore the feasibility of enhancing image quality in computed tomography(CT) pulmonary angiography (CTPA) and reducing radiation dose using the nonlinear blending (NLB)technique of dual-...Objective This study aimed to explore the feasibility of enhancing image quality in computed tomography(CT) pulmonary angiography (CTPA) and reducing radiation dose using the nonlinear blending (NLB)technique of dual-energy CT.Methods A total of 61 patients scheduled for CTPA were enrolled, and 30 patients underwent dual-energyscanning. Nonlinear blending images (NLB group) and three groups of linear blending images (LB group,80 kV group, and 140 kV group) were reconstructed after scanning;31 patients underwent single-energyscanning (120 kV group). The CT values and standard deviations of the pulmonary trunk, left and rightpulmonary arteries, and ipsilateral back muscle at the bifurcation level of the left and right pulmonaryarteries were measured. The signal-to-noise ratio (SNR) and contrast-to-noise ratio (CNR) of the fivegroups were calculated. The subjective image quality of the five groups was assessed. The radiation dosesof the dual- and single-energy groups were recorded and calculated.Results The CNR and SNR values of blood vessels in the NLB group were significantly higher than thosein the LB, 140 kV, and 80 kV groups (CNR of pulmonary artery trunk: t = 3.50, 4.06, 7.17, all P < 0.05;SNRof pulmonary trunk: t = 3.76, 4.71, 6.92, all P < 0.05). There were no statistical differences in the CNR andSNR values between the NLB group and 120 kV group (P > 0.05). The effective radiation dose of the dualenergygroup was lower than that of the single-energy group (t = –4.52, P < 0.05). The subjective scores ofimages in the NLB group were the highest (4.28 ± 0.74).Conclusion The NLB technique of dual-energy CT can improve the image quality of CTPA and reducethe radiation dose, providing more reliable imaging data for the clinical diagnosis of pulmonary embolism.展开更多
<strong>Objectives:</strong> To evaluate the diagnostic performance of the quantitative iodine parameters, including Iodine Concentration (IC), Normalized Iodine Concentration (NIC), and λ<sub>HU<...<strong>Objectives:</strong> To evaluate the diagnostic performance of the quantitative iodine parameters, including Iodine Concentration (IC), Normalized Iodine Concentration (NIC), and λ<sub>HU</sub>, in distinguishing malignant and benign thyroid nodules. <strong>Methods:</strong> Relevant studies were searched from Web of Science, PubMed, Embase, Cochrane Library, China National Knowledge Infrastructure database and other complementary sources from inception to May 20, 2020. Study selection, data extraction, quality assessment, and data analyses were performed following the Cochrane standards and the PRISMA-DTA guideline. <strong>Results: </strong>Eight studies were included (595 patients with 737 thyroid nodules). The pooled sensitivity, specificity and summary diagnostic odds ratio of IC were 79% (95% CI: 69% - 86%), 76% (95% CI: 65% - 84%) and 11 (95% CI: 5 - 27) respectively;those of NIC were 78% (95% CI: 70% - 85%), 80% (95% CI: 74% - 85%) and 15 (95% CI: 9 - 24) respectively;those of λ<sub>HU</sub> were 80% (95% CI: 71% - 87%), 77% (95% CI: 70% - 83%) and 14 (95% CI: 8 - 24) respectively. <strong>Conclusion: </strong>DECT can be a potential evaluation tool for thyroid nodules. The NIC may be the most sensitive iodine parameter and could be comparable between different DECT machines in thyroid nodule assessment.展开更多
Objective:To explore the clinical value of dual energy CT(DECT)virtual noncalcium(VNCa)in the diagnosis of sacroiliac joint bone marrow edema(BME).Methods:A collection of 45 patients(21 males,24 females,and an average...Objective:To explore the clinical value of dual energy CT(DECT)virtual noncalcium(VNCa)in the diagnosis of sacroiliac joint bone marrow edema(BME).Methods:A collection of 45 patients(21 males,24 females,and an average age of 34 years)who underwent MRI and DECT(Siemens Somatom definition force)examinations for the sacroiliac joints in our hospital from January 2019 to August 2020.After the DECT scan,the bone marrow pseudo-color map was obtained after VNCa processing.The bone marrow pseudo-color map was evaluated by two physicians.Take MRI test results as the gold standard,the application value of DECT VNCa technology in the diagnosis of sacroiliac joint BME was analyzed.Results:The positive predictive value(PPV),negative predictive value(NPV),sensitivity(Sen),specificity(Spe)and accuracy(Acc)of the qualitative diagnosis of iliac bone and sacral BME with DECT VNCa technology was:80.6%,85.2%,78.4%,86.8%,83.3%and 100%,64.9%,32.5%,100%,70.0%,respectively.The area of edema displayed by quantitative measurement of DECT VNCa image is smaller than the area measured by MRI image.The VNCa CT value(-71.66±72.97Hu)of the iliac edema area was higher than that of the non-edema area(-90.27±65.85Hu),and the VNCa CT value of the sacral edema area(-62.90±46.87Hu)was higher than that of the non-edema area(-101.08±134.02Hu),the best cut-off values(Cut-off values)for the quantitative diagnosis of iliac bone and sacral BME by VNCa are-66.40Hu and-50.60Hu,respectively.The curve of the receiver operating characteristic(ROC)of the iliac bone and sacrum area under the cure(AUC)is 0.720 and 0.706 respectively.There is a moderate negative correlation between the VNCa CT values of the ilium and sacrum in the edema area and the conventional CT values.Conclusion:The DECT VNCa technique has certain effectiveness in the diagnosis of sacroiliac joint BME,and its effectiveness in the diagnosis of ilium BME is better than sacrum.展开更多
Purpose A major challenge for the material decomposition task of the dual-energy computed tomography(DECT)is the algorithm often suffers from heavy noise in the results.The purpose of this study is to propose a scheme...Purpose A major challenge for the material decomposition task of the dual-energy computed tomography(DECT)is the algorithm often suffers from heavy noise in the results.The purpose of this study is to propose a scheme to increase the noise performance of material decomposition.Methods The scheme we propose in this paper is to apply an autoencoder-based denoising procedure to the photon-counting DECT images before they are fed into the material decomposition algorithm.We implement the autoencoder(AE)by stacking a series of convolutional and deconvolutional layers.The decomposition technique adopted in our work is an iterative method using least squares estimation with the Huber loss function.The noises of the input and the output of material decomposition are analyzed with both simulated data and real data.Phantom and chicken wing experiments are conducted with a photoncounting-based spectral CT scanner to evaluate the proposed material decomposition scheme.Results The noise analysis of the input and the output of material decomposition demonstrates a positive correlation between them.Comparative experiment indicates a noise reduction in the output density maps for 26.07%to 35.65%after the autoencoder pre-processing is applied.The resultant contrast-to-noise ratio is largely increased,correspondingly.Conclusions By utilizing the additional autoencoder denoising step,the material decomposition algorithm achieves an improvement in the noise performance of the resultant density maps.展开更多
The present study aimed to investigate the possibility of using dual-energy computed tomography (CT) before therapy to discriminate between normal breast tissue and tumor tissue in patients with breast cancer, without...The present study aimed to investigate the possibility of using dual-energy computed tomography (CT) before therapy to discriminate between normal breast tissue and tumor tissue in patients with breast cancer, without the need to use a contrast medium. The following patient data were extracted by interview and from the hospital’s radiology information system: height, weight, age, menstrual cycle, CT images of normal tissue and tumors with or without contrast medium, and the histopathological diagnosis of the aspiration biopsy. The median age of the 43 participants was 56 years (range, 30 - 80 years). The CT values were evaluated using a clinical analytical program based on the three-material decomposition technique. Breast cancer was classified into ductal carcinoma in situ, invasive ductal carcinoma, invasive lobular carcinoma, fibromatosis-like metaplastic carcinoma, and apocrine carcinoma. In all conditions, regardless of contrast medium, the CT values of tumor tissues were higher than those of normal breast tissue, indicating the effectiveness of dual-energy CT (DE-CT) in the diagnosis of breast cancer. By contrast, DE-CT showed limited potential for distinguishing ductal carcinoma in situ from invasive ductal carcinoma. There have only been a few reports regarding CT examination of breast cancer, and it is expected this study encourage the development of DE-CT imaging to improve tumor detection in patients with breast cancer.展开更多
Foreign body insertion in the urethra and bladder is not uncommon and has been reported in many studies to date. However, since foreign bodies are often accidentally introduced into the urethra and bladder during mast...Foreign body insertion in the urethra and bladder is not uncommon and has been reported in many studies to date. However, since foreign bodies are often accidentally introduced into the urethra and bladder during masturbation, they take a variety of shapes and sizes. Furthermore, patient self-reports are typically unreliable as many patients feel ashamed;thus, appropriate preoperative diagnosis is critical. Diagnosis of foreign body insertion in the urethra and bladder is performed using imaging modalities such as abdominal X-ray and computed tomography (CT). However, single-energy CT (SECT) is not sufficient in detecting foreign bodies in some cases. In the present study, we report a successful preoperative identification of urethral foreign body in a patient using dual-energy CT (DECT).展开更多
Purpose: Dual-energy CT (DECT) can be used for quantification of lung perfusion blood volume (PBV), allowing objective evaluation. However, no reports have investigated pulmonary perfusion correlating with pulmonary a...Purpose: Dual-energy CT (DECT) can be used for quantification of lung perfusion blood volume (PBV), allowing objective evaluation. However, no reports have investigated pulmonary perfusion correlating with pulmonary artery pressure (PAP) in patients with chronic pulmonary diseases. The purpose was to evaluate automated quantification of the lung PBV using dual-energy CT, and its correlation with PAP. Methods: 274 patients who underwent echocardiography within two weeks also underwent CT. The population was divided into high (≥40 mmHg) and low (<40 mmHg) estimated systolic PAP (sPAP) groups (n = 63 and n = 211, respectively). We retrospectively eva-luated the lung PBV using Syngo software, and correlations between the lung PBV and estimated sPAP. Results: Lung PBV values were 25.0 ± 9.6 and 29.0 ± 9.3 Hounsfield units (HU) in high and low sPAP groups, respectively, with a significant difference between them (p = 0.003). In the high sPAP group with underlying lung diseases (n = 15), chronic thromboembolism (n = 25), pulmonary artery stenosis (n = 12), and left heart failure (n = 11), using the Dana Point classification system, lung PBV values were 18.6 ± 1.6, 25.1 ± 4.5, 25.8 ± 4.5, and 32.7 ± 9.4 HU, respectively. There were significant differences in quantification of the lung PBV among them. The mean sPAP of subjects with left heart failure was significantly higher than in the others. In subjects with left heart failure, a positive correlation between the lung PBV value and sPAP was noted (R = 0.721, p < 0.0001). Conclusions: Automated quantification of the lung PBV may estimate the high sPAP. The lung PBV may contribute to clarifying the etiology of a high PAP due to left heart failure.展开更多
基金Supported by a grant from the Science and Technology Plan of Sichuan Province(No.2021YFS0225)the Science and Technology Plan of Chengdu(No.2021-YF05-01507-SN).
文摘Objective This study aimed to explore the feasibility of enhancing image quality in computed tomography(CT) pulmonary angiography (CTPA) and reducing radiation dose using the nonlinear blending (NLB)technique of dual-energy CT.Methods A total of 61 patients scheduled for CTPA were enrolled, and 30 patients underwent dual-energyscanning. Nonlinear blending images (NLB group) and three groups of linear blending images (LB group,80 kV group, and 140 kV group) were reconstructed after scanning;31 patients underwent single-energyscanning (120 kV group). The CT values and standard deviations of the pulmonary trunk, left and rightpulmonary arteries, and ipsilateral back muscle at the bifurcation level of the left and right pulmonaryarteries were measured. The signal-to-noise ratio (SNR) and contrast-to-noise ratio (CNR) of the fivegroups were calculated. The subjective image quality of the five groups was assessed. The radiation dosesof the dual- and single-energy groups were recorded and calculated.Results The CNR and SNR values of blood vessels in the NLB group were significantly higher than thosein the LB, 140 kV, and 80 kV groups (CNR of pulmonary artery trunk: t = 3.50, 4.06, 7.17, all P < 0.05;SNRof pulmonary trunk: t = 3.76, 4.71, 6.92, all P < 0.05). There were no statistical differences in the CNR andSNR values between the NLB group and 120 kV group (P > 0.05). The effective radiation dose of the dualenergygroup was lower than that of the single-energy group (t = –4.52, P < 0.05). The subjective scores ofimages in the NLB group were the highest (4.28 ± 0.74).Conclusion The NLB technique of dual-energy CT can improve the image quality of CTPA and reducethe radiation dose, providing more reliable imaging data for the clinical diagnosis of pulmonary embolism.
文摘<strong>Objectives:</strong> To evaluate the diagnostic performance of the quantitative iodine parameters, including Iodine Concentration (IC), Normalized Iodine Concentration (NIC), and λ<sub>HU</sub>, in distinguishing malignant and benign thyroid nodules. <strong>Methods:</strong> Relevant studies were searched from Web of Science, PubMed, Embase, Cochrane Library, China National Knowledge Infrastructure database and other complementary sources from inception to May 20, 2020. Study selection, data extraction, quality assessment, and data analyses were performed following the Cochrane standards and the PRISMA-DTA guideline. <strong>Results: </strong>Eight studies were included (595 patients with 737 thyroid nodules). The pooled sensitivity, specificity and summary diagnostic odds ratio of IC were 79% (95% CI: 69% - 86%), 76% (95% CI: 65% - 84%) and 11 (95% CI: 5 - 27) respectively;those of NIC were 78% (95% CI: 70% - 85%), 80% (95% CI: 74% - 85%) and 15 (95% CI: 9 - 24) respectively;those of λ<sub>HU</sub> were 80% (95% CI: 71% - 87%), 77% (95% CI: 70% - 83%) and 14 (95% CI: 8 - 24) respectively. <strong>Conclusion: </strong>DECT can be a potential evaluation tool for thyroid nodules. The NIC may be the most sensitive iodine parameter and could be comparable between different DECT machines in thyroid nodule assessment.
基金Project:Outstanding Youth Startup Foundation of Shanxi Province(No.2019YJ08)。
文摘Objective:To explore the clinical value of dual energy CT(DECT)virtual noncalcium(VNCa)in the diagnosis of sacroiliac joint bone marrow edema(BME).Methods:A collection of 45 patients(21 males,24 females,and an average age of 34 years)who underwent MRI and DECT(Siemens Somatom definition force)examinations for the sacroiliac joints in our hospital from January 2019 to August 2020.After the DECT scan,the bone marrow pseudo-color map was obtained after VNCa processing.The bone marrow pseudo-color map was evaluated by two physicians.Take MRI test results as the gold standard,the application value of DECT VNCa technology in the diagnosis of sacroiliac joint BME was analyzed.Results:The positive predictive value(PPV),negative predictive value(NPV),sensitivity(Sen),specificity(Spe)and accuracy(Acc)of the qualitative diagnosis of iliac bone and sacral BME with DECT VNCa technology was:80.6%,85.2%,78.4%,86.8%,83.3%and 100%,64.9%,32.5%,100%,70.0%,respectively.The area of edema displayed by quantitative measurement of DECT VNCa image is smaller than the area measured by MRI image.The VNCa CT value(-71.66±72.97Hu)of the iliac edema area was higher than that of the non-edema area(-90.27±65.85Hu),and the VNCa CT value of the sacral edema area(-62.90±46.87Hu)was higher than that of the non-edema area(-101.08±134.02Hu),the best cut-off values(Cut-off values)for the quantitative diagnosis of iliac bone and sacral BME by VNCa are-66.40Hu and-50.60Hu,respectively.The curve of the receiver operating characteristic(ROC)of the iliac bone and sacrum area under the cure(AUC)is 0.720 and 0.706 respectively.There is a moderate negative correlation between the VNCa CT values of the ilium and sacrum in the edema area and the conventional CT values.Conclusion:The DECT VNCa technique has certain effectiveness in the diagnosis of sacroiliac joint BME,and its effectiveness in the diagnosis of ilium BME is better than sacrum.
基金the National Key R&D Program of China(Grant No.2016YFC0100400)the Instrument Developing Project of the Chinese Academy of Sciences(Grant No.YZ201511)the Key Technology Research and Development Team Project of Chinese Academy of Sciences(Grant No.GJJSTD2017005).
文摘Purpose A major challenge for the material decomposition task of the dual-energy computed tomography(DECT)is the algorithm often suffers from heavy noise in the results.The purpose of this study is to propose a scheme to increase the noise performance of material decomposition.Methods The scheme we propose in this paper is to apply an autoencoder-based denoising procedure to the photon-counting DECT images before they are fed into the material decomposition algorithm.We implement the autoencoder(AE)by stacking a series of convolutional and deconvolutional layers.The decomposition technique adopted in our work is an iterative method using least squares estimation with the Huber loss function.The noises of the input and the output of material decomposition are analyzed with both simulated data and real data.Phantom and chicken wing experiments are conducted with a photoncounting-based spectral CT scanner to evaluate the proposed material decomposition scheme.Results The noise analysis of the input and the output of material decomposition demonstrates a positive correlation between them.Comparative experiment indicates a noise reduction in the output density maps for 26.07%to 35.65%after the autoencoder pre-processing is applied.The resultant contrast-to-noise ratio is largely increased,correspondingly.Conclusions By utilizing the additional autoencoder denoising step,the material decomposition algorithm achieves an improvement in the noise performance of the resultant density maps.
文摘The present study aimed to investigate the possibility of using dual-energy computed tomography (CT) before therapy to discriminate between normal breast tissue and tumor tissue in patients with breast cancer, without the need to use a contrast medium. The following patient data were extracted by interview and from the hospital’s radiology information system: height, weight, age, menstrual cycle, CT images of normal tissue and tumors with or without contrast medium, and the histopathological diagnosis of the aspiration biopsy. The median age of the 43 participants was 56 years (range, 30 - 80 years). The CT values were evaluated using a clinical analytical program based on the three-material decomposition technique. Breast cancer was classified into ductal carcinoma in situ, invasive ductal carcinoma, invasive lobular carcinoma, fibromatosis-like metaplastic carcinoma, and apocrine carcinoma. In all conditions, regardless of contrast medium, the CT values of tumor tissues were higher than those of normal breast tissue, indicating the effectiveness of dual-energy CT (DE-CT) in the diagnosis of breast cancer. By contrast, DE-CT showed limited potential for distinguishing ductal carcinoma in situ from invasive ductal carcinoma. There have only been a few reports regarding CT examination of breast cancer, and it is expected this study encourage the development of DE-CT imaging to improve tumor detection in patients with breast cancer.
文摘Foreign body insertion in the urethra and bladder is not uncommon and has been reported in many studies to date. However, since foreign bodies are often accidentally introduced into the urethra and bladder during masturbation, they take a variety of shapes and sizes. Furthermore, patient self-reports are typically unreliable as many patients feel ashamed;thus, appropriate preoperative diagnosis is critical. Diagnosis of foreign body insertion in the urethra and bladder is performed using imaging modalities such as abdominal X-ray and computed tomography (CT). However, single-energy CT (SECT) is not sufficient in detecting foreign bodies in some cases. In the present study, we report a successful preoperative identification of urethral foreign body in a patient using dual-energy CT (DECT).
文摘Purpose: Dual-energy CT (DECT) can be used for quantification of lung perfusion blood volume (PBV), allowing objective evaluation. However, no reports have investigated pulmonary perfusion correlating with pulmonary artery pressure (PAP) in patients with chronic pulmonary diseases. The purpose was to evaluate automated quantification of the lung PBV using dual-energy CT, and its correlation with PAP. Methods: 274 patients who underwent echocardiography within two weeks also underwent CT. The population was divided into high (≥40 mmHg) and low (<40 mmHg) estimated systolic PAP (sPAP) groups (n = 63 and n = 211, respectively). We retrospectively eva-luated the lung PBV using Syngo software, and correlations between the lung PBV and estimated sPAP. Results: Lung PBV values were 25.0 ± 9.6 and 29.0 ± 9.3 Hounsfield units (HU) in high and low sPAP groups, respectively, with a significant difference between them (p = 0.003). In the high sPAP group with underlying lung diseases (n = 15), chronic thromboembolism (n = 25), pulmonary artery stenosis (n = 12), and left heart failure (n = 11), using the Dana Point classification system, lung PBV values were 18.6 ± 1.6, 25.1 ± 4.5, 25.8 ± 4.5, and 32.7 ± 9.4 HU, respectively. There were significant differences in quantification of the lung PBV among them. The mean sPAP of subjects with left heart failure was significantly higher than in the others. In subjects with left heart failure, a positive correlation between the lung PBV value and sPAP was noted (R = 0.721, p < 0.0001). Conclusions: Automated quantification of the lung PBV may estimate the high sPAP. The lung PBV may contribute to clarifying the etiology of a high PAP due to left heart failure.
