ISSN 1004-4140
CN 11-3017/P

2021 Vol. 30, No. 1

Display Method:
An Enhancement Algorithm for Concrete Imaging Based on WDCT Network
SHI Changrong, XIAO Yongshun, LI Junjiang, HOU Qinhan, PENG Wenju
2021, 30(1): 1-8. doi: 10.15953/j.1004-4140.2021.30.01.01
Abstract(409) PDF(23)
Abstract:
Field loading tests with CT can research the damage evolution process of concrete under different experimental conditions, which is of great significance for the research of concrete materials. In the process of field loading tests, the occlusion of field loading equipment and the limitation of sampling time lead to the limited-angle problem and the few-view problem. Traditional algorithms can cause serious image artifacts with incomplete data. We propose to use WDCT network to enhance ART-TV reconstruction images and build a concrete simulation data set to compare the difference between our method and the classic method enhancing FBP reconstructed images with U-Net on the subjective effect and objective indicators. The experiment results show that our method can accurately reconstruct stones and cracks inside the concrete and effectively reduce image artifacts. The objective indicators of images are greatly improved.
Wave Field Simulation and Analysis of Fracture Reservoir in Xinchang, Western Sichuan
LIU Junzhou, HAO Hongjian, HAN Lei, LIANG Kai, WANG Zhenyu, CHEN Siyu
2021, 30(1): 9-22. doi: 10.15953/j.1004-4140.2021.30.01.02
Abstract:
Although the tight clastic rock reservoir in Western Sichuan depression is rich in geological reserves, the characteristics of poor physical properties, wide distribution, many strata, fracture development, strong heterogeneity and complex fluid relationship caused by complex geological conditions aggravate the difficulty of exploration and development. In view of the complexity and particularity of Xinchang exploration area in Western Sichuan, the fracture reservoir is equivalent to anisotropic reservoir, the wave equation forward modeling of VTI and HTI media is carried out, and the seismic response characteristics of fracture media in this area are analyzed. The analysis of wave field simulation results shows that the existence of fracture medium will cause the amplitude and travel time changes of reflected wave field;on the other hand, according to the travel time changes, the fracture development angle range can also be estimated.
The Combined Use of Surface Nuclear Magnetic Resonance and Self-potential in the Research of Groundwater State in the Landslide
PAN Jianwei, ZHANG Chengli, LU Kai, HONG Tao, TANG Huiming, ZHANG Bing, LI Zhenyu
2021, 30(1): 23-34. doi: 10.15953/j.1004-4140.2021.30.01.03
Abstract(312) PDF(10)
Abstract:
The spatial distribution and migration pattern of groundwater are important factors to establish groundwater flow system and analyze the seepage field. The SNMR method which is the only geophysical method that can detect groundwater directly can be used to determine the spatial distribution of groundwater, while the SP method is a geophysical method that can detect the flow direction of groundwater. The combined use of these two methods provides a better working pattern for the detection of groundwater. In this research, the detection of landslide groundwater was taken as an example. According to the water content and T1 time distribution obtained by SNMR method, using the semi-empirical method we proposed, the probability value of the slip surface in the underground space could be calculated, and then got the distribution of the slip surface. The flow direction of groundwater in landslide could be measured by the circular observation method of SP method. The combined results of the two methods provided more comprehensive hydrogeological information for the establishment of landslide groundwater model and also certified the effectiveness of the comprehensive application of the two methods.
Fault Detection and Evaluation Based on Fusion of Multiple Seismic Attributes——An Example of Fractured and Vuggy Carbonate Formation in SHB Area,Tarimu Basin
WANG Chenguang, LIN Xuemin, ZHOU Xianhua, WANG Lei, SHEN Jinsong, SU Chaoyang
2021, 30(1): 35-48. doi: 10.15953/j.1004-4140.2021.30.01.04
Abstract(294) PDF(11)
Abstract:
The fractured and vuggy reservoirs in deeply buried carbonate formation at SHB area Tarim basin are mainly deposited in fault systems ruptured by regional structural stress, the storage space consists of fractures caused by fissured faults and Karst vugs because of subsurface dissolution. Therefore, identification and evaluation of faults becomes the key step of the reservoir assessment. Considering the weakness of the seismic energy reflected from the deeply buried formation and the strong attenuation of the unconsolidated sand over the surface in the center of the deserts, the identification of faults confronts challenges with any one kind of seismic attribute. In this study, we developed a processing procedure for identification and characterization of faults with fusion of optimal seismic attributes' data set through understanding of the geological and geophysical characteristics in the target area. First, the fault caused diffusions in the seismic profiles have been identified as the suspected proofs of the existence of the faults or fractures. Secondly, methods of spectral whitening and dip angle directed filtering have been implemented for noise attenuation and frequency band extension. Next, the seismic data set after noise attenuation and frequency extension has been input into processing procedures of multiple seismic attributes calculation, such as coherence, ant tracking, and curvature. Moreover, identification and evaluation of faults in subsurface formation have been fulfilled with the fusion of multiple seismic attributes, and also the probable time window of the formation of the faults has been analyzed with the combination of the seismic profiles and attributes' slices. Finally, the sparse pulse inversion results constrained with the optimal seismic attributes and structural vectors have been applied to prediction of spatial distribution of fractures and vugs, and well consistency with the drilled results has been achieved.
Study on the Joint Application of Electrical and Seismic Exploration in the Investigation of Fissure and Karst Cave in Fuling Area
GUO Shujun, ZHU Jiliang, WANG Chunhui, REN Zhengwei, MING Yuanyuan, LI Meng
2021, 30(1): 49-59. doi: 10.15953/j.1004-4140.2021.30.01.05
Abstract(242) PDF(14)
Abstract:
Carbonate rock is the main stratum in Fuling Area shale gas exploration and development area, and the underground fissures, karst caves and underground rivers are the important geological hidden dangers to be identified and prevented. In this paper, the characteristics of audio frequency magnetotelluric method(AMT) and shallow p-wave reflection seismic method are analyzed, it is considered that the method of electric shock combined with Fissure Cave survey is an effective way to obtain the corresponding relation between abnormal structure and resistivity and wave impedance. Through two application examples, this paper analyzes the occurrence law of strata, geological structure and fissure karst water in 500 m depth underground, the exploration result is reliable, and shows the research ability of integrated geophysical exploration on carbonate karst strata, it has promoted the development of geophysical prospecting for water in Karst water-scarce areas in southwest China, and made the basic geological survey widely used in shale gas exploration and development and long-term planning in Fuling Area.
Dual-energy CT Imaging Method Based on Reference Components
WANG Wenjie, CHEN Ping, PAN Jinxiao, LI Yihong
2021, 30(1): 61-69. doi: 10.15953/j.1004-4140.2021.30.01.06
Abstract(304) PDF(13)
Abstract:

The material decomposition of dual-energy CT plays an important role in understanding the material distribution inside the substance. The X-ray energy spectrum distribution used in conventional CT is unknown, and the material attenuation coefficient cannot be obtained from the energy information, and the continuous energy spectrum projection does not match the single-energy reconstruction algorithm. There is an error between the attenuation coefficient of the reconstructed image and the theoretical attenuation coefficient of the material, and the decomposition result is not accurate. To solve the above problems, this paper introduces reference components to obtain equivalent energy information, and then obtains the single energy attenuation coefficient of the material, and introduces the Euclidean distance in the neighborhood space the tolerance restricts the material composition in the material decomposition model, and the Euclidean distance tolerance is obtained from the reconstructed image of the reference component. The experimental results show that the method in this paper can accurately decompose the materials in the detected object on the basis of the conventional CT projection system.

Calculation of Aluminum Foam Porosity Based on Multi-spectrum CT and NC-POCS Reconstruction Algorithm
QIAO Penggang, WEI Jiaotong, PAN Jinxiao
2021, 30(1): 71-80. doi: 10.15953/j.1004-4140.2021.30.01.07
Abstract:
Porosity is one of the important factors to evaluate the related properties of porous materials and an important index for material quality inspection. To solve the problem that the porosity value is greatly affected by the resolution, under the condition that the spectrum and material information are unknown, this paper, based on the multi-spectrum CT and NC-POCS(non-convex projection onto convex sets) algorithm and combined with the non-negative matrix factorization method, realizes decomposition image reconstruction. Taking the porous material aluminum foam as an example, we analyze the porosity change of the porous material under different resolutions. The experimental results show that the proposed algorithm can suppress the hardening artifacts, and the measured porosity is less affected by the resolution.
Establishment of a Diagnostic Model for Lung Adenocarcinoma with Invasive Tendency by CT and Laboratory Indexes
HUANG Guo, JIANG Beibei, JIE Xueqian, LU Huiliang, GAO Xiaolong
2021, 30(1): 81-90. doi: 10.15953/j.1004-4140.2021.30.01.08
Abstract:
Objective: To establish a multi-parameter diagnostic model to determine lung adenocarcinoma with an invasive tendency, based on 3D CT quantitative parameters of subsolid nodules(SSNs), blood tumor markers and blood routine parameters. Materials and methods: One hundred and seven patients were retrospectively included, who had thin-slice CT scan, postsurgery histological examination, and blood tumor markers, and routine blood tests. The evaluated parameters included age and gender of patients, the maximum diameter, total volume, proportion of solid components, and average CT value of SSN in CT 3D-reconstruction, as well as blood laboratory indicators: CEA, CYFRA21-1, NSE, CA125, CA153, CA242, CA199, CA724, SCC, CRP, WBC, NEUT, and NEUT%. A multiple logistic regression model was established, and the area under the receiver operating characteristic curve(AUC) was used to evaluate the diagnostic capability of the model for SSN with an invasive tendency. Results: There were significant differences in age, maximum SSN diameter, total volume, the proportion of solid components, and mean CT values between the benign and preinvasive lesion groups(51 cases) and minimally invasive and invasive adenocarcinoma groups(56 cases)(P<0.05). In the multiple regression model established by the above parameters, the maximum diameter of SSN(P=0.007) and the proportion of solid components(P=0.004) were significant. The AUCs of maximum diameter, the proportion of solid components and the regression model to determine SSNs with an invasive tendency were 0.764, 0.749, and 0.801, respectively. Conclusion: In terms of CT quantification and some blood tumor markers and blood routine parameters that can be obtained in health check examination, the establishment of a comprehensive diagnostic model using SSN maximum diameter and proportion of solid components can effectively predict the invasiveness of SSN, which is helpful for the detection of patients requiring surgery in lung cancer screening.
Applicative Study of Double Low Dose Combined with Retrospective ECG Gating in Bronchial Artery CT Angiography
LIN Guansheng, DONG Xishan, MA Zhoupeng, WANG Longting
2021, 30(1): 91-98. doi: 10.15953/j.1004-4140.2021.30.01.09
Abstract(261) PDF(13)
Abstract:
Objective: To explore the applicative value of low tube voltage and low concentration contrast agent bronchial artery(BA) CTA under retrospective ECG gating. Methods: 120 patients with hemoptysis were randomly divided into conventional dose group(group A) and double low dose group(group B), 60 cases in each group. Both groups underwent enhanced arterial phase scanning. The tube voltage was 120 kV and the concentration of contrast medium was 350 mgI/mL in group A, while the tube voltage was 80 k V and the concentration of contrast medium was 270 mgI/mL in group B. The CTA images were reconstructed after scanning, and the differences of BA display rate, image quality, and radiation dose and iodine intake between the 2 groups were analyzed respectively. Results: 115 cases completed scan successfully in the 2 groups(57 cases in group A and 58 cases in group B). The display rate of BA in group B was higher than that of group A(P<0.05); The excellent rate and qualified rate of image, noise, CT value, SNR and CNR of BA in group B were higher than those of group A(P<0.05); CTDIvol, DLP, ED and iodine intake in group B were lower than those of group A(P<0.05). Conclusion: Low tube voltage and low concentration contrast agent combined with retrospective ECG gating show important value in BA-CTA, image quality can be improved, the radiation dose and iodine intake can be reduced obviously.
Correlation Analysis of Anterior Cerebral Circulation Artery Morphology and Anterior Communicating Artery Aneurysm Based on CTA
ZHU Lin, ZHANG Min, XU Xiaowu, LU Zhiqian, WANG Suhong
2021, 30(1): 99-105. doi: 10.15953/j.1004-4140.2021.30.01.10
Abstract(138) PDF(10)
Abstract:
Objective: To investigate the correlation between the morphological parameters of anterior cerebral circulation artery and anterior communicating artery aneurysm(AcomAA). Methods: 73 patients with Acom AA were collected as the AcomAA patient group and 85 patients with normal craniocerebral CTA as the control group. Independent sample T-test was used to compare the morphological parameters of anterior cerebral circulation arteries(vessel diameter, vessel diameter ratio and vessel biforking Angle) of the ipsilateral and contralateral AcomAA patients and the control group. Results: ICA diameter on the ipsilateral side of AcomAA patients was greater than that on the contralateral side and average ICA diameter on the control group(P=0.005, P<0.001). There was no statistical significance between the contralateral ICA diameter of AcomAA patients and the mean ICA diameter of the control group(P=0.084). The ipadal A1 diameter of AcomAA patients was larger than the contralateral A1 diameter and the average A1 diameter of the control group(P<0.001, P=0.002). The contralateral A1 diameter of Acom AA patients was smaller than the average A1 diameter of the control group(P<0.001). There was no statistically significant difference between the ipsilateral and contralateral M1 diameers of AcomAA patients and the average M1 diameers of the control group(P=0.657, P=0.567). ICA/A1 ratio on the contralateral side of AcomAA patients was higher than the average ICA/A1 ratio on the ipsilateral side and control group(P<0.001, P<0.001). There was no statistically significant difference in ICA/A1 ratio between the ipilateral AcomAA patients and the mean ICA/A1 ratio in the control group(P=0.958). The ipilateral A1/A2 ratio of AcomAA patients was higher than the contralateral A1/A2 ratio and the average A1/A2 ratio of the control group(P<0.001, P<0.001). The contralateral A1/A2 ratio of AcomAA patients was lower than the average A1/A2 ratio of the control group(P<0.001). The ipsilateral A1-A2 bifurcation Angle of the Acom AA patient group was the smallest(90.80 ±19.98), and the average Angle of the control group was the largest(115.58 ±17.41),and pairwise comparison showed statistical differences(P<0.001, P<0.001, P=0.042). Conclusion: The morphology of anterior cerebral circulation artery may be correlated with AcomAA.
Accuracy Evaluation of Coronary Artery Calcification Score by Non Gated Chest CT Scan Based on Artificial Intelligence Technology
SUN Huili, CHEN Jie, ZHANG Huan, CUI Bin, GUO Chao, WU Xiaoyin, GUO Ning, WANG Zhiqun
2021, 30(1): 106-113. doi: 10.15953/j.1004-4140.2021.30.01.11
Abstract(458) PDF(23)
Abstract:
Objective: To evaluate the accuracy of coronary artery calcification score(CACS) by non-gated low-dose chest CT plain scan using artificial intelligence. Methods: A total of 100 cases of patients with coronary CTA scanning were retrospectively analyzed. All patients were selected for ECG gated CT scan and routine non-gated chest CT plain scan. The calcification score of non-gated chest CT plain scan was recorded by Agatston calcification integral software in Siemens post-processing workstation, and the calcification score of non-gated chest CT plain scan was recorded by artificial intelligence analysis software. Two scanning methods were used to obtain Agatston score, including total coronary artery(TOTAL) score, left main artery(LM) score, left Left anterior descending artery(LAD) score, circumflexcoronaryartery(CX) score, and right coronary artery(RCA) score. Paired T-test was used to compare the statistical differences between the two groups. Pearson correlation coefficient was used to analyze the correlation of the two groups' calcification scores, and intra-group correlation coefficient(ICC) was used to test the consistency of risk stratification of the two groups' calcification scores. P<0.05 was considered statistically significant. Results: there was no statistically significant difference in the Agatston score of LM, CX and RCA between the two groups(P<0.05), while there was a statistically significant difference in the calcification score of LAD between the two groups(P<0.05). Pearson analysis found the significant correlation between the two groups in the Agatston score of TOTAL, LM, CX, RCA and LAD. ICC analysis found that the Agatston calcification scores of the two groups showed good consistency in risk stratification, with an intra-group correlation coefficient of 0.938, P<0.001. Conclusion: The artificial intelligence-based non-gated chest CT plain scan has a high accuracy in the evaluation of coronary artery calcification score, which is in good agreement with the traditional gated examination in terms of risk stratification, and can be used for the screening and assessment of coronary heart disease risk.
Imaging Findings of Undifferentiated Embryonal Sarcoma of the Liver in Adults
QIU Ganbin, LIAO Weixiong, WEN Zhongyan, CHEN Jincan
2021, 30(1): 114-123. doi: 10.15953/j.1004-4140.2021.30.01.12
Abstract:
Objective: To investigate the CT and MRI features of undifferentiated embryosarcoma(UESL) of the liver in adults. Materials and methods: the clinical and imaging data of 5 patients with ueslwere analyzed retrospectively. Results: the lesions were single in 5 cases, 4 in the right lobe of the liver and 1 in the left and right lobe of the liver. CT/MRI showed a solid mass with fuzzy boundary, nodular and irregular soft tissue density/signal shadow on the wall of the cyst, uneven separation of thick wall, low density on CT plain scan, large liquefaction and necrosis on MRI plain scan, long T1 and long T2 signal changes on MRI plain scan, and slightly progressive enhancement on CT/MRI enhanced scan of wall nodule, soft tissue composition and separation in the cyst. Conclusion: the imaging findings of adult UESL have certain diagnostic value, which is helpful for preoperative diagnosis.
The Diagnostic Value of Multislice Spiral CT in Lymph Node Metastasis of Colon Cancer
FENG Li, CHEN Weibin, LI Gai, ZHOU Wei
2021, 30(1): 124-130. doi: 10.15953/j.1004-4140.2021.30.01.13
Abstract:
Objective: To evaluate the value of short-to-long-diameter ratio(SLR) combined with relative enhancement in the diagnosis of lymph node metastasis of colon cancer. Methods: 47 cases of colon cancer diagnosed by surgery in our hospital were analyzed retrospectively. All patients underwent plain abdominal CT scan and enhanced CT scan. The parameters of short diameter, ratio of short to long diameter, CT value and relative enhancement value of abdominal suspicious lymph nodes were recorded. The results were compared with each other. ROC curve was drawn to analyze the diagnostic value of each parameter. Results: compared with non-metastatic lymph nodes, the value of short diameter, short-to-long diameter ratio, CT value of plain scan, arterial and venous phase and relative enhancement value of metastatic lymph nodes were significantly increased(P<0.01). The ROC curves were 0.649, 0.725, 0.713, 0.723, 0.696, 0.793 for short diameter, ratio of short to long diameter, CT value of plain scan, arterial and venous phase and relative enhanced value, respectively, the sensitivity was 63.30%, 76.70%, 73.30%, 60.00%, 76.72%, 73.30%, and the specificity was 75.00%, 70.00%, 60.00%, 65.00%, 90.00% respectively, the sensitivity and specificity were 86.70% and 85.00%, respectively. The Kappa Coefficient was 0.787. Conclusion: The short-to-long-diameter ratio(SLR) combined with the relative enhanced value of MSCT has high sensitivity to lymph node metastasis of colon cancer, which can provide important evidence for clinical diagnosis of lymph node metastasis.
Study on the Correlation between the Volume of Epicardial Adipose Tissue and Lumbar Bone Mineral Density
CHENG Haiping, PENG Zhoufeng, LI Liang, CENG Feifei, CHA Yunfei
2021, 30(1): 131-138. doi: 10.15953/j.1004-4140.2021.30.01.14
Abstract:
Objective: To investigate the relationship between epicardial adipose tissue(EAT) volume and Lumbar bone mineral density(BMD). Methods: In this study, we retrospectively analyzed non-contrast CT images and QCT images from 600 patients. Subjects were grouped according to BMD. The EAT was extracted from the chest CT images of the admitted patient and the volume was calculated. The difference of EAT volume was detected by one-way analysis of variance. The correlation between BMD and EAT was tested by Pearson Correlation Coefficient. A two-sided P<0.05 was considered significant. Results: There was a significant difference in the volume of EAT among the normal group, osteopenia group and osteoporosis group(F=65.80, P<0.001), and there was a negative correlation between the volume of epicardial fat and BMD(r=-0.805 [95% CI:-0.858,-0.745]). The area under the curve of BMD, the volume of epicardial fat and the clinical mixed model were 0.80(95% CI:0.75 ~ 0.83), 0.75(95% CI:0.72 ~ 0.81) and 0.88(95% CI:0.81 ~ 0.94), respectively. The clinical benefit thresholds of lumbar BMD, epicardial fat volume and clinical mixed model were 0.02 ~ 0.89, 0.05 ~ 0.82 and 0.01 ~ 0.98, respectively. Conclusion: The volume of EAT is closely related to the BMD of lumbar spine. The volume of EAT might be used as a potential biomarker to evaluate the BMD of lumbar spine. The diagnosis model based on clinical factors has a good prediction effect on low back pain in physical examination population.