CT理论与应用研究

Combined Boundary of CPML and Feature Analysis within Frequency-Space Domain

LI Guihua, WANG Shulin, ZHANG Wenbo, XU Ziyu

2022, 31(3): 269-279. doi: 10.15953/j.ctta.2021.075

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Abstract:
In the process of numerical simulation, boundary reflection is an important factor which affect the numerical simulation results. The actual underground medium holds anisotropic characteristics. The traditional perfectly matched layer boundary (PML) shows good effect on small incident angle seismic waves, yet it can not effectively absorb low-frequency waves and large angle incident waves. To solve the problem of boundary reflection, in this paper, we propose a combined boundary condition using convolution perfectly matched layer (CPML) and eigenvalue analysis method to be applied in the numerical simulation of finite difference method in frequency space domain. The numerical simulation experiment and boundary reflection absorption effect analysis of the combined boundary condition verify that the proposed method is a reliable artificial absorption boundary condition, which can effectively suppress the boundary reflection generated in the process of wave field simulation.

Application of Joint Inversion of Different Electrode Arrays in Ancient Mausoleum Detection

WEI Yunong, SHI Zhanjie, YU Tianxiang

2022, 31(3): 280-292. doi: 10.15953/j.ctta.2022.008

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Abstract:
Electrical resistivity tomography is a popular geophysical method and has been applied in shallow exploration, involving hydrology, archaeology, and geology, in recent years. To enhance the resolution of electrical resistivity tomography and deal with complex geological settings, we propose the weighted combined inversion of different electrode arrays based on the Jacobian matrix, and then, taking Wenner and dipole-dipole datasets as examples, test its effectiveness on synthetic models and a field case of detecting ancient mausoleum. The results show that the resolution of the weighted combined inversion results is superior to that of a single electrode array in transverse and longitudinal directions, and in the field case, it is demonstrated that the weighted combined inversion algorithm can alleviate the inherent defects of U-shaped electrode array, reduce the ambiguity of inversion, and better constrain the width of the mausoleum.

Application of Double Width Seismic Data to Channel Sand Body Prediction of X Gas Field in the East China Sea

HU Wei, QIN Dewen, LI Qin, YU Weizhe, HUANG Jun

2022, 31(3): 293-304. doi: 10.15953/j.ctta.2021.017

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Abstract:
Due to that the main reservoirs of the X gas field in the East China Sea were deeply buried and have large lateral changes, the conventional seismic data resulted in poor quality and low resolution, which couldn’t meet the increasingly refined geological requirements in exploration and development. Seismic data with wideband and wide azimuth was obtained by using the acquisition method of three ships and four sources with oblique cables, which held the characteristics of high resolution, high signal-to-noise ratio and high fidelity. By taking advantage of the superior information of wideband and wide azimuth seismic data which was high-resolutional and anisotropic, combined with the simultaneous prestack inversion, the inversion body of sensitive elastic parameters of channel sand bodies in different azimuths can be obtained, and superimpose multiple azimuth inversion bodies perpendicular to the direction of the river channel to carry out fine predictions of channel sand bodies. Compared the conventional seismic data, reservoir inversion based on wideband and wide azimuth seismic data improved the prediction accuracy of channel sand bodies, laying a foundation for the progressive exploration and development of the X gas field in the East China Sea.

Application of Lame Parameter Direct Inversion in Hydrocarbon Detection of Low-porosity and Low-permeability Reservoirs in N Structure in East China Sea Basin

ZHANG Yan, QIN Denwen, HUANG Jun

2022, 31(3): 305-316. doi: 10.15953/j.ctta.2021.088

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Abstract:
The main target layer of the N structure in the East China Sea is a delta subaqueous distributary channel sand body developed under a strong hydrodynamic environment. The distribution of planar sand layer is discontinuous and the lateral heterogeneity is very strong. Under the influence of deep burial compaction and diagenesis, the reservoir is characterized by low porosity and low permeability, and the properties of rock-physics are overlapped seriously. In addition, the lack of large angle information of deep seismic data is a common problem. It is of great importance to implement the fluid distribution range of tight reservoir in the study area for the design and deployment of exploration and development. In this paper, a new method of deep seismic fluid description is introduced based on direct inversion of lame parameters. Through qualitative and quantitative analysis of rock-physics of measured well data, optimal highly sensitive hydrocarbon detection factor is selected. Furthermore, the AVO properties of Lambda parameters are extracted from the pre-stack trace set by combining with the parametric equations of the two AVO models of Lambda parameters. Then, the AVO properties are directly transformed into the interlayer elastic information by using the colored inversion technique. Finally, the seismic fluid sensitive elastic data is obtained to guide the seismic fluid description. The practical application shows that the hydrocarbon detection results of this method are compatible with the logging interpretation achievement, and can effectively describe the low-porosity and low-permeability reservoirs fluid development law of the study area, and can provide important technical support for the discovery of oil and gas resources in new fields.

Coded Aperture Computed Tomography Via Generative Adversarial U-net

WANG Zhiteng, MAO Tianyi, ZHANG Xin, ZHU Shujin, ZHU Jianjian, DAI Xiubin

2022, 31(3): 317-327. doi: 10.15953/j.ctta.2021.070

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Abstract:
Generative adversarial U-net for coded aperture computed tomography (CT) is proposed in this paper to alleviate the tradeoff between the non-continuous sparse projections and the ill-posedness iterative reconstruction problem. A non-continuous sparse projection model is presented based on generative adversarial U-net and the corresponding joint penalty function is formulated. Simulations using real datasets show that CT images with 256×256 pixels can be reconstructed with peak signal-to-noise ration more than 30 dB at only 5% transmittance. Furthermore, the computational time in the reconstructions is reduced by two orders of magnitude when compared with the state-of-the-art iterative algorithms in coded aperture computed tomography.

Application of Deep Learning Reconstruction Algorithm in Upper Abdomen CT

WEN Deying, YANG Jieyin, WANG Qin, LI Zhen, WANG Hanxiao, WANG Aijie, DENG Qiao, TANG Lu, WU Xi, YAO Jin, LU Chunyan, SUN Jiayu

2022, 31(3): 329-336. doi: 10.15953/j.ctta.2021.005

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Abstract:
Objective: To explore the application of deep learning image reconstruction (DLIR) algorithm in upper abdominal CT imaging by analyzing the image quality of adaptive statistical iterative reconstruction (ASIR) algorithm and DLIR. Methods: Retrospectively included 75 patients’ upper abdominal CT plain scan images, using adaptive statistical iterative reconstruction algorithm ASIR (30%, 50%, 70%, 90%) and deep learning reconstruction algorithm (DL-L, DL-M, DL-H) to reconstruct images, a total of 7 groups. Measured the CT and SD values of the liver, pancreas, and erector spinae , and calculated the signal to noise ratio (SNR) and contrast to noise ratio (CNR). Objective indicators were evaluated by one-way ANOVA. Two radiologists scored the image quality and noise, and compared them with Friedman M test. Results: (1) The SD value, SNR, and liver CNR of the seven reconstructed images had statistically significant differences. (2) The difference in CT value, SD value, SNR value and CNR value at each ROI between DL-L and ASIR 50%, DL-M and ASIR 70%, DL-H and ASIR 90% was small. (3) The SNR value of the three DLIR algorithms increased as the level increased, and the difference was statistically significant; and the SNR value of the DL-H algorithm was higher than ASIR 30% and ASIR 50%, and the SD value was lower than the other five reconstruction algorithms except for the ASIR 90%. (4) The difference in the subjective scores of the seven groups of images was statistically significant. The algorithm DL-H had the best image quality and the lowest noise, DL-M, ASIR 90%, DL-L, ASIR 70%, ASIR 50%, ASIR 30% image noise in sequence increased. Conclusion: The DLIR algorithm can reduce the image noise of the upper abdomen and improve the image quality. As the level increased, the image noise decreased, the quality improved, and the signal-to-noise ratio increased.

Imaging Features and Etiology of Acute Cerebral Infarction in Bilateral PICA Territory

SUN Rujing, ZHANG Shiyu, CHENG Xu, QIAO Penggang

2022, 31(3): 337-344. doi: 10.15953/j.ctta.2022.060

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Abstract:
Objective: To investigate the MRI features and etiology of acute cerebral infarction in bilateral PICA territory. Methods: 38 patients with bilateral PICA and 40 patients with bilateral SCA diagnosed clinically and radiographically in Beijing Friendship Hospital of Capital Medical University from January 2019 to January 2022, were retrospectively analyzed. The difference of MRI features, were compared between the two groups, according to the size of the infarction, the distribution of infarcted lesions in posterior circulation or anterior circulation. The range of acute infarction in the bilateral PICA territory and the changes of vertebrobasilar artery were analyzed. Results: The proportion of the infarction model of one side regional infarction with the other side small infarct in bilateral PICA was significantly higher than that in bilateral SCA (39.5% vs. 15%), while the model of small infarction on both sides was lower than that in bilateral SCA (44.7% vs. 72.5%). The incidence of infarction in other blood supply areas of the combined posterior circulation was significantly lower than that in bilateral SCA (21% vs. 80%). The infarction models of bilateral PICA manifested as unilateral total infarct of PICA territory combined with the other unilateral infarct of mPICA territory (44.7%) or bilateral mPICA territory (39.5%). Unilateral vertebral artery V4 segment or PICA-localized severe stenosis/occlusion were more frequently detected in acute infarcts in bilateral PICA (54.2%). Conclusions: Bilateral PICA territory infarction mainly manifested as unilateral total infarct of PICA territory combined with the other unilateral or bilateral infarct of mPICA territory, and regional infarction was quite common, which was closely related to anatomical variation.

Phantom Study on the Influence of CT Model and Tube Voltage on Image Quality

FANG Shu, CHEN Linyu, CHEN Yong, DONG Haipeng, WANG Lan, MIN Jihua

2022, 31(3): 345-350. doi: 10.15953/j.ctta.2021.042

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Abstract:
Objective: To compare the image quality between two CT scanners under two different tube voltages using a dedicated phantom. Materials and Methods: Siemens SOMATOM Force CT and Phillips Spectral IQon CT were used for scanning and the dedicated Assurance Quality Phantom Catphan 500 was applied. Module CTP 528 and CTP 515 were performed for evaluation of high resolution and low-contrast sensitivity, respectively. Four sets of images of two scanners were acquired, including group A to D whic represented force 120 kVp, force 140 kVp, IQon 120 kVp and IQon 140 kVp. The dosage of all four set of images was 20mGy.Evaluation of high resolution was carried out by two radiologists via the smallest line pair one could distinguish and low-contrast sensitivity was measured by the smallest diameter under 1% contrast. Mean noise, signal-to -oise ratio (SNR) and contrast-to-noise ratio (CNR) were also evaluated for each group. Results: Group A and C had the highest high resolution with a line pair of 6 lp/cm; the same low-contrast sensitivity was observed by all the groups (diameter of 5 mm). Group A showed the smallest noise (2.500±0.000) and highest SNR (30.806±1.398). Noise and SNR were both significantly different among four groups. The highest CNR (3.325±0.300) was observed in Group D, but no statistical difference was found among the four groups. Conclusion: Image quality varied under different CT scanners and tube voltages. Images with 120 kVp showed better contrast compared with those with 140 kVp. 120 kVp with force CT showed improved image noise than that of 140 kVp images; while for IQon spectral CT, no obvious difference in noise parameters was found between the two tube voltages.

Image Quality Assessment for Deep Learning Image Reconstruction Algorithm: A Phantom Study

LIU Fangtao, LIU Heshi, CHEN Yong, JIANG Jiang, WANG Lingyun, DONG Haipeng, ZHANG Yong, ZHANG Xuan, KONG Deyan, CHANG Rui

2022, 31(3): 351-356. doi: 10.15953/j.ctta.2021.061

Abstract(257) HTML PDF(16)

Abstract:
Objective: To compare the image quality between the deep learning image reconstruction (DLIR) and iterative reconstruction (IR) algorithms via the dedicated phantom. Method: ACR quality assurance phantom (Gammex 464) was scanned by GE Revolution Apex. The CT value accuracy, low contrast resolution, image uniformity and high contrast resolution of five substances from module 1 to module 4 were measured respectively. Through the above indicators, the image quality of three levels (DL, DM and DH) of Truefedelitytm (TFI) and three levels (30%, 60% and 90%) of adaptive statistical iterative reconstruction-V (asir-V, hereinafter referred to as AV) under high dose (20 mgy) were compared. The comparison between the two algorithms for each parameter was tested by One-Way Anova. Results: The high/low-contrast resolution of the six image series were consistent (high-contrast resolution: 10 lp/cm; low-contrast resolution: 6 mm). The two algorithms both slightly overestimated the CT value of polyethylene, air and acrylic, and no statistically significant difference was found among the difference of CT values of the substances. Both algorithms underestimated the CT value of bone and the solid water; TFI showed better performance in evaluating the solid water which was closer to the real value, though statistical difference was not found between each group of images. Among the 6 groups of images, TFI DH showed the best image uniformity and at the same reconstruction level, TFI showed better uniformity than AV. Conclusion: DLIR can further reduced image noise while maintaining image spatial resolution and CT value accuracy at high dose level.

Application of IMR, iDose⁴ and FBP Reconstruction Algorithms in CT Scanning of Rhinoplasty

XU Tongjiang, WANG Xu, LI Yan, DENG Gang, LIU Jianxin, YIN Xiaoming, LIANG Weizhong, WU Ge

2022, 31(3): 357-364. doi: 10.15953/j.ctta.2021.072

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Abstract:
Objective: To investigate the effects of IMR, iDose⁴ and FBP reconstruction algorithms on the image quality of multi-row spiral CT in the chest before costal cartilage rhinoplasty. Methods: A total of 60 patients who met the inclusion criteria and planned to receive autogenous costal cartilage rhinoplasty were collected. All patients underwent chest CT examination before operation and completed relevant 3D reconstruction based on images generated by IMR, iDose⁴ and FBP reconstruction algorithms, and the image quality of the three reconstruction algorithms was analyzed. The subjective evaluation score and objective evaluation indexes of image quality in each group were recorded and compared including costal cartilage CT value, noise, signal-to-noise ratio and contrast noise ratio. Results: The CT reconstruction images obtained by the three algorithms could all accurately assess the degree of costal cartilage calcification. Subjective evaluation of image quality showed that the IMR group obtained higher score and held obvious advantages, mainly reflected in the IMR reconstruction algorithm compared with iDose⁴ and FBP two algorithms in the costal cartilage calcification spot edge display and inhibition of liver, gastrointestinal content and weakened heart beating artifacts. Objective evaluation of costal cartilage CT value, SNR, contrast noise ratio and statistical analysis, the final statistical results showed that IMR, iDose⁴ and FBP reconstruction algorithm group showed significant statistical differences, IMR group showed obviously the best image quality. Conclusion: All three reconstruction algorithms of IMR, idose⁴ and FBP can accurately evaluate the presence and degree of calcification of autologous costal cartilage. Under the same scanning conditions, compared with the reconstruction algorithms of FBP and iDose⁴, IMR reconstruction algorithms can reducecan significantly reduce image noise, improve CNR and SNR, and improve the subjective image quality of costal cartilage. It is more acceptable to clinical surgeons and can be used as the preferred algorithm reconstruction technique for costal cartilage CT examination, which is most worthy of promotion.

Spectral CT Multi-material Decomposition in Evaluation of Secondary Lower Extremity Lymphedema: A Prospective Study

GUO Jia, XIN Jianfeng, ZHANG Chunyan, GUO Lifang, WANG Mengjun, WANG Rengui, DONG Jian

2022, 31(3): 365-371. doi: 10.15953/j.ctta.2022.004

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Abstract:
Objective: To explore the application value of spectral CT multi-material decomposition (MMD) algorithm in the grading of secondary lower extremity Lymphedema. Materials and methods: Prospective collection of patients who underwent spectral CT admitted to our hospital from June 2019 to June 2020 were prospectively collected. The spectral CT images were analyzed by two radiologists with more than five years of experience in CT diagnosis. The volume of the both lower limbs were measured using the threshold value software. Based on the percentage increase in the volume of the affected side compared to the healthy side, the enrolled patients were divided into three grades: mild, moderate, and severe. Percentage fat volume fraction (FVF) images were generated by using the MMD algorithm on spectral CT to measure the fat content of the affected and healthy lower limbs respectively. Paired t test were used to analyze the difference of the percentage FVF between the affected and healthy side in mild, moderate, severe patients. Results: Forty patients (female/male, 36/4 cases, with age range of 32-71 years old, median age of (53±10) years) were finally enrolled, and the course of disease was (3±5) years. There were 8 cases in mild group, 14 cases in moderate group and 18 cases in severe group. There were statistical differences in the percentage FVF between the affected and healthy side in mild, moderate and severe patients. There was no statistical difference in the percentage FVF of the affected side among mild, moderate and severe patients.Conclusion: The spectral CT MMD algorithm can quantify the percentage FVF of Secondary Lower Extremity Lymphedema, but it cannot be used alone in the grading of secondary lower extremity lymphedema.

Predictive Value of Dual-energy CT Left Ventricular Iodinogram Combined with Plasma BNP in the Development of Heart Failure after AMI

ZHANG Huan, HAN Xu, CUI Bin, CHEN Jie, YU Haitao, WANG Zhiqun

2022, 31(3): 373-382. doi: 10.15953/j.ctta.2021.068

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Abstract:
Objective: To investigate the value of dual-energy CT left ventricular iodinogram imaging and plasma B-type natriuretic peptide level in the early diagnosis and prediction of heart failure and severity in patients with acute myocardial infarction. Methods: AMI patients admitted to our hospital from January 2018 to December 2019 were selected to complete dual-energy coronary artery CTA and plasma BNP examination, and cardiac function grading was assessed within 1 week after admission. Myocardial iodine content was measured to evaluate the myocardial perfusion on dual-energy CT. The correlation between myocardial iodine content, left ventricular ejection fraction and BNP level was analyzed, and the differences of myocardial perfusion, LVEF and BNP levels among different Killip cardiac function grading groups in HF patients were compared. Results: A total of 115 patients with AMI were enrolled, including 42 patients in HF group and 73 patients in non-HF group. There were significant differences in myocardial iodine concentration, LVEF and BNP between the two groups. Iodine concentration and LVEF were negatively correlated with BNP (r=−0.527, −0.674). The ROC curve showed that the AUC of myocardial iodine concentration combined with BNP in predicting HF after AMI was higher than that of iodine map and BNP alone. Among the 42 HF patients after AMI, with the increase of Killip grade, serum BNP level increased, LVEF and iodine content of infarct myocardial decreased, and there were statistically significant differences in BNP, LVEF and iodine content of infarct myocardial among different grade groups. Conclusion: Dual-energy CT left ventricular iodinogram combined with BNP level has predictive value on the occurrence of heart failure after acute myocardial infarction, and has a certain correlation with the clinical severity of heart failure.

A Preliminary Study on the Value of Texture Analysis in Predicting Bleeding Complications of CT-guided Percutaneous Lung Biopsy

XU Jingci, PAN Zilai, CHEN Kemin, CHEN Xiaoyong, LIU Xiao

2022, 31(3): 383-391. doi: 10.15953/j.ctta.2021.016

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Abstract:
Objective: In this paper we intends to explore the value of texture analysis based on CT image in predicting the complications of percutaneous pulmonary puncture hemorrhage under the guidance of CT. Methods: The preoperative plain scan images of 130 patients who underwent CT-guided percutaneous lung biopsy were analyzed retrospectively. The patients with pulmonary hemorrhage greater than or equal to grade 2 in the operative area were assined into the bleeding group while the patients with grade 0 or grade 1 pulmonary hemorrhage were assined into the no / small bleeding group. 100 cases were randomly selected as the training group, and the lung field around the pre-puncture path on the plain scan lung window image was manually drawn as the region of interest (ROI) by using MaZda software. The most valuable texture features were selected by methods of Fisher coefficient, classification error probability joint average correlation coefficient (POE+ACC) and interactive information (MI) to distinguish between bleeding group and no / small amount of bleeding group. Then, the four following feature classification statistical methods; raw data analysis (RDA), principal component analysis (PCA), linear classification analysis (LDA) and nonlinear classification analysis (NDA), were used for judgement, and the results were shown by way of error rate. Finally, the other 30 cases were verified according to the optimal texture parameters and feature classification method. Results: The lowest error rate was 11.00% (11/100) when the lung field around the puncture path was used as ROI. The error rates were respectively 13.33% (4/30) and 16.67% (5/30), when the feature selection method was POE+ACC or MI, and the feature classification statistical method was NDA, there was no significant difference between the two groups. Conclusion: The analysis of the texture characteristics of the lung field around the puncture path is helpful in predicting the risk of pulmonary puncture complicated with hemorrhage under the guidance of CT, and can provide certain basis for selecting a suitable puncture path to reduce the complications of pulmonary hemorrhage.

Analysis of the Manifestations of ENT in Low-dose Oral CBCT Examination

RAN Xueqi, LI Jianfeng, CAO Shaoai

2022, 31(3): 392-398. doi: 10.15953/j.ctta.2021.035

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Objective: To investigate the manifestations of ear, nose and throat (ENT) related tissues and imaging manifestations by cone beam computed tomography (CBCT) examination in oral diseases. Methods: The data of 300 patients who underwent oral CBCT examinations in our hospital from July 2019 to May 2020 were retrospectively analyzed, and the display of tissue structures outside their teeth was recorded. Anatomical structures mainly include sinuses, nasal cavity, pharyngeal recesses, mastoid and surrounding soft tissues. The anatomical display rate of the above tissues (maxillary sinus, sphenoid sinus, frontal sinus and ethmoid sinus) in the imaging image was independently evaluated by double-blind method, and the display of tissue structure and the imaging contrast between tissue structures were scored. All data were analyzed statistically, and the results were statistically significant. Results: In oral CBCT, under the low-dose X-ray, the maxillary and sphenoid sinuses in the paranasal sinuses can be well displayed on CBCT, but the frontal and ethmoid sinuses cannot be displayed; nasal cavity and ethmoid sinus pharyngeal crypts got excellent results, and bilateral mastoid got good results. The gas and bone quality between the tissues were displayed well, and the scores between the soft tissue, fat and fluid were significantly different, while the soft tissue, fat and fluid were not displayed well, and there was no significant difference in the scores among the three. Conclusion: Low-dose CBCT in oral examination can well show the relevant anatomy of the maxillary sinus, sphenoid sinus, nasal cavity, and pharyngeal recess. We shouldn’t ignore the disease detection of these tissue structures in the analysis of imaging results, but the contrast between soft tissue structures is poor, the qualitative diagnosis of these tissue structure diseases needs further examination.

The Predictive Value of CT Findings in Invasive Behavior of Pancreatic Neuroendocrine Tumors

CHEN Xiaoyong, XU Jingci, LI Qinqin, PAN Zilai

2022, 31(3): 399-407. doi: 10.15953/j.ctta.2021.082

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Abstract:
Objective: To explore the value of CT findings in predicting the invasive behaviors of pancreatic neuroendocrine tumor (pNET). Methods: The clinical data and CT data of 120 patients with pNET confirmed by surgical resection and pathology were retrospectively analyzed. Preoperative CT plain scan and enhanced examination of pancreas were performed. Image analysis included tumor location, shape, capsule, cystic change, calcification, pancreatic duct dilation and enhancement pattern. The maximum and minimum diameter of the tumor were measured. The CT value of the solid part of the tumor was measured in plain scan, arterial phase and portal vein phase. Enhancement difference in arterial phase and portal vein phase were calculated. The tumors were divided into invasive group and non-invasive group according to the pathological results. The difference of CT findings between the two groups was compared. Receivers operating characteristic (ROC) curves were drawn to evaluate the predictive value of tumor maximum diameter, minimum diameter, enhancement difference in arterial phase and portal vein phase on the invasive behavior of pNET. Results: There were no statistical differences in tumor location, pancreatic duct dilation, cystic change, calcification and enhancement pattern between the invasive and non-invasive groups. There were statistically significant differences between the two groups in the quantitative characteristics of the maximum diameter, the minimum diameter, enhancement difference in arterial phase and portal vein phase and the areas under ROC curve were 0.693, 0.69, 0.73 and 0.64, indicating discrimination efficiency. Multivariate Logistic regression analysis of 6 meaningful image features showed that arterial enhancement difference was an independent predictor of pNET invasive behavior, and the optimal critical point of arterial enhancement difference was 90.1HU (sensitivity 0.714, specificity 0.656, positive predictive value 64.5%, negative predictive value 72.4%, accuracy 68.3%). Conclusion : Large volume, irregular shape, incomplete or no capsule of pancreatic neuroendocrine tumor, and low enhancement difference of solid tumor components in arterial and portal phases suggested invasive behavior of tumor, and enhancement difference in arterial phase was an independent predictor of invasive behavior of pNET.

Clinical Imaging Characteristics and Pathological Features of Sarcomatoid Hepatocellular Carcinoma

ZHAI Xiali, WANG Lixia, LI Xue

2022, 31(3): 409-416. doi: 10.15953/j.ctta.2022.057

Abstract(144) HTML PDF(12)

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Objective: To explore the imaging manifestations and clinical-pathological features of sarcomatoid hepatocellular carcinoma (SHC). Methods: The clinical data, CT/MRI findings and pathological features of 7 patients with SHC were retrospectively analyzed and the consistency was evaluated. Results: SHC showed unclear boundary and low density by plain CT images, with the size ranging from 4.2 cm×4.7 cm–14.0 cm×11.0 cm. By enhanced CT images, SHC showed ring or early enhancement with large areas of necrosis. SHC showed heterogeneous signal intensity on T1WI and T2WI with visible cystic degeneration and necrotic area while DWI displayed obvious diffusion restricted changes. On enhanced MRI, the tumor showed progressive enhancement of peripheral and solid components with delayed enhanced pseudo-capsule. 6 cases had different degree of necrosis in the center of lesion, and lymph node metastasis in the livers hilar was found in 5 patients. Pathological features polygonal and fusiform tumor cells with extensive necrosis and hemorrhage were found on HE staining. Vimentin and CK were positive by immunohistochemical staining. Conclusions: The imaging findings of SHC were consistent with the pathological features, which was helpful to deep understanding of specific imaging manifeatations, and the diagnosis and differential diagnosis of liver tumors.

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2022 Vol. 31, No. 3