CT理论与应用研究

Research on the Application Value of ¹⁸F-FDG PET/CT Comwith Neuronal Antibody Detection in the Diagnosis and Treatment of PNS Patients

YUAN Leilei, CHEN Qian, QIAO Zhen, LI Xiaotong, FAN Di, ZHANG Wei, AI Lin

, Available online , doi: 10.15953/j.ctta.2022.070

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Objective: To explore the whole body ¹⁸F-FDGClinical value of PET/CT combined neuroantibody detection in the diagnosis and treatment of paraneoplastic neurological syndromes (PNS). Methods: Clinical, laboratory and imaging data of 56 hospitalized patients with suspected PNS who underwent systemic ¹⁸F-FDG PET/CT and neuropathic tumor antibody detection were retrospectively collected and followed up. ROC curve was performed to compare the diagnostic efficacy of PET/CT, neuronal antibody and the combined detection results of them. Results: Among the 56 patients with suspected PNS, there were 20 patients with malignant tumor, including 19 cases complicated with PNS and 1 patient with spinal cord metastasis which also lead to neurological symptoms. ¹⁸F-FDG PET/CT imaging indicated tumor or possible tumor in 23 cases, of which 20 cases were true positive, 3 cases were false positive (the follow-up results were reflux esophagitis, reactive bone changes, inflammatory lesions in neck), and the remaining 33 cases were true negative. The sensitivity, specificity and accuracy of PET/CT were 100%, 91.7% and 94.6%, respectively. There were 33 cases with positive neuroantibody, including 8 cases of tumor with PNS (3 cases with anti-Amphiphysin antibody encephalitis, 2 cases with anti-GABAb antibody encephalitis, 1 case with anti-Yo antibody encephalitis, and 2 cases with anti-Hu antibody encephalitis). There were 25 cases without tumor (10 cases with LGI1 antibody encephalitis, 3 cases with anti-amphiphysin antibody encephalitis, 1 case with anti-Hu antibody encephalitis, 3 cases with anti-GABAb antibody encephalitis, 3 cases with anti-Yo antibody encephalitis and 1 case with Anti-caspr2, 1 case with GAD65, 1 case with NMDA, 1case with PNMA and 1 case with SOX1 antibody (1 case each) 23 cases were negative (12 cases with tumor). The sensitivity, specificity and accuracy of neuronal antibody test were 40.0%, 30.6% and 33.9%, respectively. The sensitivity, specificity and accuracy of the combined detection were 100.0%, 33.3%, 57.1%, 50%, 94.4%, 78.6%, respectively. ROC analysis showed that AUC were 0.958 (P=0.000<0.05; 95% CI 0.904~1.000), 0.353 (P=0.070>0.05; 95% CI 0.199~0.506), 0.667 (P=0.040<0.05; 95% CI 0.528~0.806) and 0.672 (P=0.034<0.05; 95% CI 0.514~0.830). Conclusion: Whole body ¹⁸F-FDG PET/CT can be the first choice for noninvasive tumor screening in patients with suspected PNS.

Evaluation of Invasion of Pulmonary Subsolid Nodules by Artificial Intelligence Volumetric Density Method

WANG Jingchen, CHAI Jun

, Available online , doi: 10.15953/j.ctta.2022.099

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Objective: To explore the value of artificial intelligence (AI) volumetric density method in determining the invasion of pulmonary hyposolid nodules (SSNs). Methods: 108 SSNs and pathological results of 106 patients were reviewed, divided into glandular prodromal lesions group and adenocarcinoma group. Pulmonary nodule AI software was used to measure and compare the CT quantitative parameters of the two groups, including maximum CT value, minimum CT value, average CT value, kurtosis, skewness, Perc.25%, Perc.50%, Perc.75%, Perc.90%, nodule volume and mean nodule diameter. Receiver operating characteristic curve (ROC) was obtained by Medcalc software to evaluate the sensitivity, specificity, positive predictive value and negative predictive value for the diagnosis of SSNs infiltration, and their diagnostic performance was evaluated by logistic regression analysis. Results: There were significant differences in most CT quantitative parameters of SSNs. The highest diagnostic efficiency was Perc.25% and AUC was 0.797. Perc.50% and CT mean, AUC were 0.787. Logistic regression analysis showed that Perc.25% with the highest diagnostic efficiency was combined with Perc.50% and CT mean value, respectively. The model with Perc.25% and CT mean value had the highest diagnostic efficiency, and the combined diagnostic model had higher diagnostic efficiency than Perc.25% and CT mean value alone. According to Medcalc software, SSNs with Perc.25% ≥−578 HU and mean CT value ≥ −468 HU are more likely to be adenocarcinoma group. In this study, Perc.25% was combined with the mean diameter of nodules, and a very valuable combined diagnostic model II was obtained to judge the infiltration of SSNs. Conclusion: AI volume density method has a high diagnostic value for SSNs invasion. The combination of Perc.25% and mean CT value can accurately judge the invasion than the use of average CT value alone, thus providing a quantitative basis for the clinical management of SSNs.

Evaluation of Diagnostic Value of Pulmonary Nodules Based on Two AI Softwares

CHEN Xinhua, HUANG Xiaoqi, LI Jianlong, GUO Youmin

, Available online , doi: 10.15953/j.ctta.2022.087

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Objective: To explore the clinical value of two kinds of AI detection software in ≥ 5 mm pulmonary nodules. Methods: A total of 92 patients with pulmonary nodules (483 nodules) were selected from June 2021 to October 2021 in the affiliated Hospital of Yan'an University. The nodules detected by AI software were evaluated and the number and type of nodules were recorded by two senior radiologists. Manual film reading was evaluated by two senior imaging doctors, which was used as the gold standard for nodule recognition. The detection rate, false positive rate and false negative rate of the two software’s were calculated, and the nodule detection value of the two AI software was evaluated. Chi-square test and Fisher precision test are used to compare the differences between different software and gold standard. Finally, the diagnostic value of the combination of two kinds of AI software for pulmonary nodules was calculated. Results: The detection rates of software A and software B nodules were 92.1% and 87.0% respectively. The coincidence degree between software A and manual reading was general (Kappa=0.213), while that between software B and manual reading was weak (Kappa=0.150). There was significant difference in the detection of solid nodules and calcified nodules between software A and manual reading, and between software B and pure ground glass nodules. The detection rate of nodules combined with two kinds of AI software was 97.1%. Compared with manual reading, there was no significant difference in the detection of nodule types. The combination of the two AI software’s had a good agreement with manual reading (Kappa=0.439). Conclusion: Two kinds of AI software association improve the ability of nodule detection and classification analysis. The method of joint diagnosis is recommended for clinical use, and it also provides evidence for further improving the homogenization management of AI data sets.

Application of Comprehensive Geophysical Prospecting Method in Goaf Detection

TANG Su, WU Yinting, XING Hao, WEI Yongshan, WANG Xuan

, Available online , doi: 10.15953/j.ctta.2022.176

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To accurately explore distribution of a historical small coal mine goaf in Hami, Xinjiang, integrated application of microtremor and transient electromagnetic is used for goaf exploration researching. This work use different physical properties data into lithology, use microtremor exploration to determine the goaf position and use transient electromagnetic exploration identify goaf water. Two methods can complement each other, verify each other, and effectively reduce the wrong results of single geophysical method. Which also provides a reference for the selection and application of geophysical exploration means in small mine goaf exploration.

Research Progress of Scattering Artifact Correction in Medical Cone-beam Computed Tomography Imaging Based on Deep Learning

ZHANG Wenjun, HUANG Gang, DING Haining, XU Hongchun

, Available online , doi: 10.15953/j.ctta.2022.131

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In the medical computed tomography imaging system, Compton scattered photons and Rayleigh scattered photons generated by the interaction between X-ray and objects have serious impact on image quality, especially in cone beam computed tomography and multi-layer detector system compared to fan beam computed tomography system. At present, there have been many scattering artifacts correction methods, which are summarized into three categories: hardware correction methods, software correction methods and hybrid software and hardware correction methods. However, with the advances in computing power of computers and the development of deep learning in medical image processing, some new methods of scattering artifacts correction have appeared in recent years. This paper first introduces the traditional correction methods. Then, the method of scattering artifacts correction based on deep learning is introduced in detail, which is divided into image domain learning method and projection domain learning method. Different deep-learning neural networks in this method are introduced in detail too. Finally, the application prospects of the deep learning method in multi-source computed tomography imaging scattering artifacts are prospected.

CT and MRI Findings of Multiple Infarcted Regenerative Nodules in Liver Cirrhosis after Variceal Hemorrhage

XU Xiaoli, ZHANG Tao, ZHANG Xueqin

, Available online , doi: 10.15953/j.ctta.2022.063

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Objective: To investigate the CT and MRI features of multiple infarcted regenerative nodules in cirrhosis after variceal hemorrhage. Methods: A total of 21 patients, including 13 males and 8 females, who were diagnosed with multiple infarction regenerating nodules in cirrhosis after variceal hemorrhage, were included in this study. All patients were examined by 3.0TMR scanner or 256 slice spiral CT, the enhancement pattern, signal intensity, shape, number, size, edge, location and distribution of lesions were analyzed. Results: In CT or MRI imaging, 3 patients had 10 or less lesions, and 19 patients had more than 10 lesions. The diameter of liver lesions was 3～26mm.Most lesions are round nodules, most of the lesions were clustered and distributed. The lesions were mainly distributed in the subcapsular region of liver. After dynamic enhancement of CT and MRI, most nodules have no obvious enhancement, and a few can have marginal enhancement. On T1WI images, all lesions showed equal signal or slightly low signal. On T2WI images, most lesions are high signals with clear boundary. During CT and MRI follow-up, the lesions disappeared in 13 patients and shrank or significantly reduced in 8 patients. Conclusions: CT and MRI can show the imaging features of multiple infarcted regenerative nodules in liver cirrhosis after variceal hemorrhage, which can be differentiated from liver malignancy by image follow-up, clinical history, and tumor indicators.

Research and Application of Adaptive Multi-channel Matching Pursuit Method to Remove Strong Shielding

WANG Xi'an, ZHANG Junhua, XIA Lianjun, LUO Zhen, HU Yifu, BAO Wei

, Available online , doi: 10.15953/j.ctta.2022.120

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The strata with large impedance differences are presented as strong amplitude seismic events on the seismic profile, which will obscure the useful information of the nearby reservoir and need to do the interpretive target processing to remove the strong shielding. To address the problem of poor matching accuracy and spatial continuity of normal multi-channel matching pursuit in the place of strong tectonic changes, this paper proposes a multi-channel matching pursuit de-strong shielding method based on adaptive weights. Firstly, we use the layer structure information to flatten the strong reflection layer locally to weaken the influence of the stratigraphic structure changes on the extraction of the strong reflection layer, and then introduce the correlation coefficient between adjacent seismic traces and the central trace as the weight of multi trace averaging, which improves the stability and lateral continuity of the matching results. Meanwhile, using the interpreted layer time as the initial central time delay of the wavelet can effectively improve the compute efficiency. The analysis of model processing tests and practical seismic data application shows that the new method can effectively strip the strong reflections and highlight the effective reservoir information, and the well seismic match degree is significantly improved, with higher matching accuracy and better spatial continuity and better striping effect than the conventional matching pursuit algorithm.

Imaging Features and Clinical Significance of Segond Fracture

HE Weihong, FU Xi, FANG Tingsong, WANG Guining, WANG Juan

, Available online , doi: 10.15953/j.ctta.2022.112

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Objective: To evaluate the imaging features of Segond fracture and explore its clinical value in lateral instability of the knee joint. Methods: Retrospectively analyze 45 cases of Segond fracture. Analyze the characteristics of the fracture, included the relationship between the fracture and the ligaments around the knee joint, meniscus injury, the size and location of the fracture block. The significance of Segond fracture in clinical treatment was discussed. Results: Among 45 cases of Segond fracture, 41 cases (91.11%) had anterior cruciate ligament (ACL) injury, 31 cases (68.89%) had anterolateral ligament (ALL) injury, and 12 cases (26.67%) had iliotibial bundle (ITB) injury. ALL were all attached to the fracture block, and 25 cases (55.55%) were attached to the ITB. The larger the size of the fracture block and the smaller the distance from the center of Gerdy's nodule, the more likely the fracture block will be attached to the ITB. Conclusion: Segond fracture is often associated with ACL injury, involving ALL and ITB. The larger the fracture block and the closer to the center of Gerdy's nodule, the greater the possibility of involving ITB. Patients with Segond fracture should be alert to lateral instability of the knee joint.

CT Spectral Imaging Study in Patients with Carotid Body Tumors at High Altitude

ZHOU Dongmei, YIN Guixiu

, Available online , doi: 10.15953/j.ctta.2022.059

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Objective: To investigate the value of CT spectral imaging in the study of carotid body tumor (CBT). Methods: 30 patients with CBT who underwent CT energy spectrum examination and were confirmed by operation were collected. 60 keV and 40 keV single energy images are reconstructed through the GSI viewer. The CT value, background noise (SD), contrast noise ratio (CNR), signal-to-noise ratio (SNR) and subjective score of CBT feeding arteries of 40 keV, 60 keV single energy images and 120 kVp like images were statistically analyzed. To analyze the relationship between CBT energy spectrum parameters and imaging features and surgical results. Results: There was no correlation between energy spectrum parameters in arterial phase and venous phase of CBT and surgical results. CBT transverse diameter, longitudinal diameter and Shamblin classification were strongly correlated with intraoperative bleeding, and the number of feeding arteries was moderately correlated with intraoperative bleeding. The transverse diameter, longitudinal diameter and Shamblin classification were moderately correlated with cranial nerve injury, and the number of feeding arteries was strongly correlated with cranial nerve injury. 40 keV was the best energy level for CBT feeding artery display. The CT value, SD, CNR and SNR of 60 keV group were significantly higher than those of 60 keV group and 120 kVp like group. The CT value and noise of 60 keV group were significantly higher than those of 120 kVp like group. There was no significant difference in CNR and SNR between the two groups. The subjective evaluation score of 40 keV group was the highest, and the subjective evaluation of the two radiologists had good consistency. Conclusion: (1) There is no correlation between the parameters of energy spectrum in arterial phase and venous phase of CBT and GAPP score. (2) The number of CBT feeding arteries is one of the important parameters for evaluating surgical complications. 40 keV single energy imaging can significantly optimize the display of CBT feeding arteries.

CT and MRI Features and Prognosis of Necrotic Accumulation in Patients with Acute Pancreatitis

YAN Wei, DONG Lining, ZHANG Binbin, YANG Dawei, YANG Zhenghan, WANG Zhenchang, JIN Erhu

, Available online , doi: 10.15953/j.ctta.2022.141

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Objective: To summarize the imaging features of acute necrotizing accumulation (ANC), a local complication of patients with acute necrotizing pancreatitis (ANP), and to explore the factors affecting the prognosis of ANC. Methods: The clinical and imaging data of 31 patients with ANP were retrospectively analyzed. The imaging characteristics of ANC were observed on CT or MRI. The follow-up outcomes were divided into absorption group and wrapping necrosis (WON) group. Chi square test was used to compare the statistical differences between the two groups. Results: Plain CT showed patchy uneven low-density shadows in 31 cases of ANC, accompanied by focal analogous circular iso-, low-density mixed shadows in 23 cases and fatty low-density shadows in 22 cases; Plain MRI showed mixed low signal intensity on T1 and mixed high signal intensity on T2 in 19 cases of ANC, within it low signal fragments were seen on FS T2WI. The ANC was complicated with local infection in 3 cases (9.7%) and hemorrhage in 12 cases (38.7%). The necrotic tissues did not show any enhancement, but their surrounding tissues could appear as patchy or linear enhancing changes in varying degrees on enhanced scans. The follow-up (median 137 days) of 31 patients found that ANC was completely absorbed in 12 cases (38.7%), and developed into WON in 19 cases (61.3%). There were significant differences in the necrosis involving the pancreas, affected locations of the pancreas, volume of the necrosis, and MCTSI scores between the absorption group and the WON group. Conclusion: ANC shows uneven liquid densities on CT and heterogeneous signal intensities on MRI. The necrotic tissue itself has no enhancement, but its surrounding tissue presents different degrees of enhancing changes on enhanced scan. Follow-up finds that the ANC can completely dissipate or form WON, which is related to many imaging factors.

Automatic Identification of Relationship Between Tooth Root and Mandibular Canal Based on One-step Deep Neural Network

ZHOU Yan-qi, DAI Xiu-bin, WANG Dong-miao, ZHU Shu-jin, MAO Tian-yi

, Available online , doi: 10.15953/j.ctta.2022.083

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To improve the accuracy and efficiency of identifying the relationship between the root of the impacted mandibular third molar (M3M) and the mandibular canal in panoramic radiographs, an automatic method based on a deep convolutional neural network was proposed in this paper. This method treats the automatic identification of the relationship between the root of the M3M and mandibular canal as a combination of regression task and classification task. It uses YOLOv5 (You Only Look Once) network as the framework to construct the deep convolutional neural network which can accomplish the detection task and classification task simultaneously. This network, which takes the spatial relationship information extracted from the corresponding cone-beam CT images as the ground-truth, was trained to learn the nonlinear relationship between image features and the root of the M3M contacting with the mandibular canal. When inputting a newly acquired panoramic radiograph into the trained network, the network will output the probability value for the root of the M3M contacting with the mandibular canal. In the meantime, the region which includes the root of the M3M contacting with the mandibular canal can be predicted. The experimental results show that the proposed method can give an accurate judgment of whether the roots of impacted mandibular wisdom teeth in the panoramic radiographs are in contact with the mandibular canal, as well as the location of regions in which there exist the roots of the M3M contacting with the mandibular canals; compared to manual diagnosis and the other methods, the proposed method can obtain more accurate results.

Natural Gas Hydrate CT Image Threshold Segmentation Based on Time Evolution

CHEN Liang, YE Wangquan, LI Chengfeng, SUN Jianye, ZHENG Ronger

, Available online , doi: 10.15953/j.ctta.2022.062

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Micro-scale X-ray computed tomography (CT) has been widely used to study the occurrence forms of gas hydrate-bearing sediments. However, the similarity on X-ray’s attenuation coefficient of hydrate and water leads to strong non-uniqueness in phase differentiation between them in CT images. In order to improve threshold segmentation accuracy between hydrate and water in CT images, this paper proposed a CT image and histogram normalized method by analyzing the histogram characteristics of CT images at different times in the growth process of natural gas hydrate. Firstly, choose peak gray value baseline of methane gas and quartz sand. Then, use Gaussian function to fit methane gas and quartz sand curves in the current CT image histogram to obtain the peak gray values. In addition, the peak gray values of methane gas and quartz sand in the current CT image histogram were normalized to the chosen peak gray baseline. After that, the normalized histogram is used to normalize corresponding CT images. Finally, according to the changing trend of normalized gray histogram curves, the gray ranges of hydrate increasing and gas-water decreasing in CT images can be obtained quantitatively, which can guide the CT images threshold segmentation. Experimental results show that the proposed threshold segmentation method can provide a basis for the phase differentiation of hydrate and water in CT image, improve the threshold segmentation accuracy.

Computed Tomography Reconstruction Algorithm Based on Relative Total Variation Minimum

ZHANG Fengjia, QIAO Zhiwei

, Available online , doi: 10.15953/j.ctta.2022.190

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The total variation (TV) minimization algorithm is an effective CT image reconstruction algorithm, which can reconstruct sparse or noisy projection data with high accuracy. However, in some cases, the TV algorithm will produce stepped artifacts. In the field of image denoising, the relative TV algorithm shows better performance than TV algorithm. In view of this, the relative TV model is introduced into image reconstruction, the relative TV minimum optimization model is proposed, and the corresponding solution algorithm is designed under the framework of adaptive gradient descent projection to convex set (ASD-POCS) to further improve the reconstruction accuracy. The reconstruction experiments are carried out with Shepp Logan, Forbild and real CT image simulation models to verify the anti crime ability of the algorithm and evaluate the sparse reconstruction ability and anti noise ability of the algorithm. The experimental results show that compared with TV algorithm, the algorithm can achieve anti crime and can reconstruct sparse or noisy projection data with high precision. Compared with TV algorithm, the algorithm can achieve higher reconstruction accuracy.

Application of Real Size Film Printing Technology in Costal Cartilage CT Image

CAO Jie, BI Zihan, LI Bo, WANG Yongzhen, XIN Gang, Mao Xiaoying, LIU Li

, Available online , doi: 10.15953/j.ctta.2022.135

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Objective: To explore the film printing technology for displaying the true size of costal cartilage on medical film. Methods: The CT images of costal cartilage of 31 patients were selected and processed 14×17 inches (35×43 cm), calculate the main image display area and 14×17 the scale between the actual image display areas on the film shall be made into physical scales of 10 cm and 5 cm in length. Print the film in 2×2. Four images are arranged in the grid, and the transverse or sagittal images of single rib cartilage are printed on a 5 cm physical scale; with 1×1 The grid is a single image layout, and the 3D images of all the front rib arches (including costal cartilage) are printed on a 10 cm physical scale. The film measurement values of six indicators, including the length of the ascending and transverse parts of the right sixth costal cartilage, the width and thickness of the transverse junction of the ascending part, the thickness of the sternal end of the costal cartilage and the rib end of the costal cartilage, were compared with the solid measurement values during the operation, and statistical analysis was made. Results: (1) The printed film was measured, and the 10 cm and 5 cm scales shown on the film were equal to the actual size of the ruler. (2) There was no significant difference between the measured values of six groups of costal cartilage images on film and the measured values of costal cartilage entities during surgery. Conclusion: The printing technology based on DICOM protocol can realize the real size printing of costal cartilage CT image on film. The morphological data of the target tissue obtained by the operator from the film are reliable.

The Value of Spectral CT in Differential Diagnosis and Radiotherapy Localiation of Central Lung Cancer with Obstructive Atelectasis

LIU Xiuli, ZHANG Jifeng, LIU Jingwang, LI Jian, XU Mei, CHEN Jing

, Available online , doi: 10.15953/j.ctta.2022.164

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Objective: To investigate the value of spectral CT in differential central lung cancer from obstructive atelectasis for achieving the accurate delineation and radiotherapy localiation. Methods: The CT radiotherapy localiation images of three phase contrast enchancement by spectral CT of 65 patients confirmed by pathology with central lung cancer and obstructive atelectasis with were collected and analyzed. The scores and detection rates of tumor-lung interface between the polychromatic image (PI), the best monochromatic image (BMI), the effective atomic number (Eff-Z) and the best monochromatic image combined with iodine concentration map (BMI-ICM) were compared. Results: Statistical differences in the scores of tumor-lung interface were observed between PI, BMI, Eff-Z and BMI-ICM; the pairwise comparison showed that the subjective score of BMI-ICM was the highest, and PI was the lowest. The pulmonaty artery phase detection rates of tumor-lung interface of three phase contrast enchancement were the highest. There was statistical difference of iodine concentration (IC) and CT score between lung cancer and obstructive atelectasis. The difference of IC was higher Zhan the CT score. Conclusion: Spectral CT is helpful to distinguish central lung cancer delineation from atelectasis. It provides a new method to delineate the radiotherapy localiation for radiotherapy plan of optimization.

In Vivo Study of the Influence of CT Acquisition and Reconstruction Parameters on Chest CT Number

LI Jingjing, ZHANG Li, LIU Mengwen, YANG Shouxin, LI Meng, JIANG Jiuming, YU Weijun

, Available online , doi: 10.15953/j.ctta.2022.109

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Objective: To explore the influence of different CT acquisition and reconstruction parameters on the CT number of the chest in vivo. Methods: The CT number of the trachea, blood vessels, lungs, vertebral bodies, and muscles of the human chest were measured under different CT scanning parameters. Six groups of different scanning parameters and reconstruction algorithms were set respectively: slice thickness 5 mm, 50% multi-model adaptive statistical iterative reconstruction Veo (ASIR-V) and low-dose for S1; slice thickness 5 mm, filtered back projection (FBP) and standard-dose for S2; slice thickness 1.25 mm, 50% ASIR-V and low-dose for S3; slice thickness 1.25 mm, 50% ASIR-V and standard-dose for S4; slice thickness 1.25 mm, FBP, low-dose for S5; slice thickness 1.25 mm, FBP, standard-dose for S6. The radiation dose of the scan was controlled using two noise indexes (NI), including low-dose (NI=40) and standard-dose (NI=10). Differences in CT number between two groups were compared using t-test or rank-sum test. Results: Significant differences of CT number of the trachea were detected between low-dose and standard-dose, but no significant differences of CT number of other tissues were detected between low-dose and standard-dose. No significant differences of CT number of chest tissues were detected between either 5 mm thickness and 1.25 mm thickness or 50% ASIR-V and FBP. Conclusion: The CT number of human chest tissues showed well stability which was scarcely influenced by slices thickness, reconstruction algorithm and scan dose.

Study of Correlations between CT and MRI Findings and Elevated Serum IgG4 Levels in Newly-diagnosed Patients with IgG4-related Sclerosing Cholangitis

DONG Lining, YAN Wei, ZHANG Jie, YANG Dawei, LIU Peng, XU Hui, YANG Zhenghan, Wang Zhenchang, JIN Erhu

, Available online , doi: 10.15953/j.ctta.2022.158

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Objective: To observe the CT and MRI findings in newly-diagnosed patients with IgG4-related sclerosing cholangitis (IgG4-SC), and to explore their correlations to the serum IgG4 and IgG levels. Methods: The clinical, laboratory and imaging data of 50 newly-diagnosed IgG4-SC patients were retrospectively summarized. The type of lesions, shape of lumen stenosis and degree of dilatation of the diseased bile ducts on MRCP, and the characteristics and enhancement patterns of the thickened bile duct walls, in addition to the number of coexisted other IgG4-RDs on enhanced MRI and CT were observed. Then the correlations of the patients' baseline serum IgG4 and IgG levels with the severity of bile duct lesions and the number of coexisted other IgG4-RDs were analyzed. Results: 41 patients underwent MRCP examinations, IgG4-SC type Ⅰ in 28 cases, type Ⅱa in 11, type Ⅲ in 1, and type Ⅳ in 1 were identified. Extrahepatic bile duct stenosis was funnel-shaped in 37 cases and truncated in 4 cases. All the stenotic segments were long (≥1.0cm) and 1 diverticulum-like outpouching was seen in the pancreatic segment stenosis. Upstream bile ducts of the stenosis showed dilatation in 37 cases, the other 4 cases did not. Contrast-enhanced MRI and CT examinations showed continuous thickening of the extrahepatic bile duct walls in 42 cases, and diffuse thickening of the intrahepatic bile duct walls simultaneously in 15 cases among them. The thickness of the bile duct walls was uniformly concentric. Meanwhile, accompanied other IgG4-RDs included AIP in 50 cases, kidney involvement in 19 cases, salivary gland involvement in 7 cases, retroperitoneal fibrosis in 5 cases, and liver involvement in 4 cases, lung involvement in 4 cases, prostate involvement in 2 cases, sclerosing mediastinitis in 2 cases, thickened gallbladder wall (without stones) in 20 cases, enlarged upper abdominal lymph nodes in 15 cases. Higher baseline serum IgG4 and IgG levels were positively correlated with the number of coexisted other IgG4-RDs, but not with the bile duct wall thickness and stenotic segment length. Conclusions: Localized stenosis of the bile ducts with dilatation or non-dilation of the upstream bile ducts, as well as diffuse thickening of the bile duct walls are the MRI and CT features of newly-diagnosed patients with IgG4-SC. Higher baseline serum IgG4 and IgG levels are not related to the severity of the diseased bile ducts, but related to the number of coexisted other IgG4-RDs.

Shallow Profile Data Denoising Method Based on Improved Cycle-consistent Generative Adversarial Network

ZHANG Yi, DING Renwei, ZHAO Shuo, SUN Shimin, HAN Tianjiao

, Available online , doi: 10.15953/j.ctta.2022.053

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In order to solve the problem of more noise and low resolution of shallow profile data, this paper applies the method of cycle generative adversarial network to the denoising of shallow profile data to realize intelligent denoising. Firstly, the cycle generative adversarial network with special symmetric generation countermeasure network cycle mechanism and "cycle consistency loss" is selected. We improve the performance of e-learning and training by changing the network structure. Then, based on the optimized shallow profile sample set training network, the random noise of shallow profile data is removed and the signal-to-noise ratio of data is improved. Through the trial calculation of experimental and actual data and the comparison with the traditional band-pass filtering method, the effectiveness and adaptability of this method for denoising shallow profile data are verified.

Progress in Clinical Application of Fractional Flow Reserve Based on Coronary CT Angiography

LI Shihang, ZHANG Xiaoqin

, Available online , doi: 10.15953/j.ctta.2022.037

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Noninvasive coronary fractional flow reserve derived from CT angiography (FFR_CT) is a major advance in cardiovascular imaging in recent years. It can identify pathology-specific ischemia and provide information for clinical decisions on revascularization, serving as a gatekeeper for invasive coronary angiography.This paper reviews the research progress of FFR_CT and briefly discusses its limitations.

Research Progress of Radiomics in the Diagnosis of Pulmonary Nodules

LIU Yuting, LIU Aishi

, Available online , doi: 10.15953/j.ctta.2022.056

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In recent years, with the continuous improvement of medical level, people pay more attention to their own health, pulmonary nodules and other space-occupying lesions can be detected earlier, but on a global scale, the number of deaths caused by malignant lung lesions Still rising and remaining high. Radiomics is an emerging field that aims to derive automated quantitative imaging features from medical images to noninvasively predict nodular and tumor behavior. Compared with traditional visual image features, radiomics can extract more nodular features with better reproducibility. The scientific and systematic use of radiomics can not only prevent excessive medical behaviors and reduce the economic burden of patients, but also enable patients with lung lesions to receive early treatment for the best prognosis.

Correlation between CT Arterial Enhancement Fraction and TACE Efficacy of Hepatocellular Carcinoma

GONG Na, ZHU Bingjie, YU Peijun, ZHAO Lin, SHI Ke, LI Huian

, Available online , doi: 10.15953/j.ctta.2021.022

Abstract(26) HTML PDF(3)

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Objective: To explore the correlation between CT arterial enhancement fraction (AEF) and the curative effect of transcatheter arterial chemoembolization (TACE) for hepatocellular carcinoma (HCC). Methods: The clinical data of 43 patients with HCC in the hospital from January 2019 to January 2020 were enrolled in this study. Three-phases CT enhancement scans were performed before and 1 month later after TACE treatment, they were divided into effective group and ineffective group according to different efficacy. The level of alpha-fetoprotein (AFP) was detected by electrochemical luminescence method in each group. The changes of AEF, AFP and tumor size before and after treatment were compared between the two groups. The correlation between AEF, AFP and changes of tumor size was explored by Pearson correlation coefficient. The evaluation value of dynamic enhancement scan combined with AEF for TACE efficacy was analyzed by receiver operating characteristic (ROC) curves and area under the curve (AUC). Results: After treatment, AEF, AFP and tumor size in effective group were decreased after TACE treatment, lower than those in ineffective group. The results of Pearson correlation analysis showed that AEF and AFP were positively correlated with tumor size after TACE. The results of ROC curve analysis showed that AUC of dynamic enhancement scan combined with AEF for evaluating TACE efficacy was 0.902, significantly greater than that of dynamic enhancement scan and AEF alone (0.793, 0.771). Conclusion: AEF is a reliable parameter for evaluating the therapeutic effect of TACE. The efficacy evaluation of TACE treatment will be further improved by AEF combined with dynamic enhanced scan, which should be applied as an auxiliary method for evaluating TACE efficacy on HCC.

Quantitative CT Analysis of Body Composition in Maintenance Hemodialysis Patients

LV Lei, ZHAI Jian, LI Yuncheng, ZHAO Yazi, LIU Yan

, Available online , doi: 10.15953/j.ctta.2022.050

Abstract(58) HTML PDF(6)

Abstract:
Objective: Analyze body composition information in patients on maintenance hemodialysis, to explore the application value of QCT technology. Methods: A total of 62 patients with maintenance hemodialysis were selected, divided into 3 groups according to different dialysis durations, and the bone density value, abdominal fat and muscle content of patients were determined by quantitative CT technology, and 62 cases of health examination population matching gender and age were selected for comparative analysis. Results: Osteoporosis accounted for 17.70% (11 cases) and bone loss in the dialysis group accounted for 30.60% (19 cases), while in the healthy control group, osteoporosis and bone loss accounted for 6.50% (4 cases) and 16.10% (10 cases), respectively, and the difference between the two groups was statistically significant; the intra-abdominal fat and subcutaneous fat content in the dialysis group were (113.70±63.29) cm², (80.65±59.67) cm², respectively. All were lower than the healthy control group (135.90±58.80) cm², (122.26±54.94) cm², the dialysis group L3-SMA< control group L3-SMA, (107.00±30.70) cm²< (121.37±32.87) cm², all with statistical differences, and the lumbar vertebral bone density value of male dialysis patients was (156.11±51.94) (mg/cm³) in different sex dialysis patients. Compared with women (124.29±50.89) (mg/cm³), the difference was statistically significant, and the subcutaneous fat content was higher than that in men while the difference in intraperitoneal fat content in men and women was not statistically significant; the difference between bone density values and L3-SMA changes in the dialysis group and the length of dialysis time was not statistically significant. Conclusion: The incidence of osteoporosis is higher in patients on maintenance hemodialysis than in healthy people, and the amount of abdominal fat and muscle content are lower than that in healthy people, Quantitative CT body composition monitoring have high accuracy and sensitivity.

The Lithospheric Structure of the Middle Solonker−Xar Moron Suture by Surface-wave Tomography

FENG Mei, AN Meijian, HOU Hesheng, FAN Taoyuan, ZANG Hulin

, Available online , doi: 10.15953/j.ctta.2022.061

Abstract(107) HTML PDF(11)

Abstract:
The middle section of the Solonker−Xar Moron suture and its surrounding areas have successively experienced the closure of the Paleo-Asian Ocean in Paleozoic, the closure of the Mongolian-Okhotsk Ocean in Mesozoic, and the Pacific Ocean subduction since Meso-Cenozoic, resulting in very complex deep structures in this area. We conducted a regional-scale three-dimensional S-wave velocity tomographic study for the area using surface waves from earthquake data and from ambient noise data recorded in recent years. The lithospheric tomographic model shows that the regional crustal thickness is weakly varied, but the crust in the Songliao Basin and the Lower Liaohe Basin is thinner than that of the Daxing'an Mountains. The consistency of the crustal thickness with topography indicates that these areas basically reach gravitational equilibrium status. However, the crustal thickness of the Liaodong uplift and the Bohai Bay Basin is inversely correlated with topography, indicating that these areas may still be in a tectonic active state. At depths of >80 km, the S-wave velocities spread in an east-west direction approximately parallel to the Solonker−Xar Moron suture. Separating by the Solonker−Xar Moron suture, the complexity of upper-mantle velocity distribution in the north is significantly different from that in the south; and in the south, the complexity of velocity distribution in the east is also quite different from the west, implying that the destruction resulted by the Pacific Ocean subduction system varies significantly within the study region, and the remanent of the paleo-Asian ocean slab may exist in the south.

Imaging Diagnosis of Nuchal-type Fibroma

LIANG Dezhi, JIN Cangzheng

, Available online , doi: 10.15953/j.ctta.2022.048

Abstract(44) HTML PDF(4)

Abstract:
Objective: To study the CT and MRI findings of nuchal-type fibroma. Methods: 8 cases of surgically resected and pathologically confirmed nuchal-type fibroma were retrospectively analyzed. Results: All lesions were firm and located in subcutaneous tissue of sacrococcygeal region. CT and MRI showed local skin thickening. The lesions were ill-defined and had irregular morphology. The lesions showed slightly high density on CT, low signal intensity on T1WI and T2WI, and isosignal on DWI. Enhancement scanning was performed in 2 patients, with 1 mild enhancement and 1 moderate enhancement. Conclusion: The CT and MRI findings of nuchal-type fibroma have some characteristic features. Combining with the medical history and clinical manifestations, the diagnosis could be made.

Correlation between Carotid Atherosclerotic Plaque and Acute Ischemic Stroke

ZAN Qin, CHEN Xiaorong, YANG Wenqiong

, Available online , doi: 10.15953/j.ctta.2022.039

Abstract(31) HTML PDF(3)

Abstract:
Objective : Carotid artery CTA was used to analyze carotid atherosclerotic plaque, and to explore the correlation between plaque properties and some factors and acute ischemic stroke, so as to provide reference and basis for the prevention and treatment of acute ischemic stroke. Methods: Patients who underwent carotid artery CTA and underwent magnetic resonance DWI within one week before or after carotid artery CTA were retrospectively analyzed. The patients were divided into acute ischemic stroke group (n=95) and non-acute ischemic stroke group (n=102) according to magnetic resonance DWI. The clinical data, laboratory data and the nature and surface morphology of carotid plaques displayed by CTA were analyzed to compare the statistical differences between the two groups. The indexes of P<0.05 were included in the multivariate logistic regression analysis of acute ischemic stroke. Results: There were significant differences in age, hypertension history, TC, TG, HDL, HCY, CysC and HbA1c between the two groups. Multivariate regression analysis showed that age ≥65 years, hypertension, high TC, high Hcy, high HbA1c and lipid plaque were independent risk factors for acute ischemic stroke. High level of HDL is protective factor for the development of acute ischemic stroke. Conclusion: Carotid atherosclerosis is related to the occurrence of acute ischemic stroke, and lipid plaque is a risk factor for acute ischemic stroke. Carotid artery CTA can judge the nature of plaque, combined with some laboratory indicators; it can provide reference and basis for the prevention and treatment of acute ischemic stroke.

Design and Implementation of 3D C-arm Control Service Protocol (RoboLINK) Based on DICOM

GAO Chen, CHENG Kun, CHANG Yunheng, ZHANG Fei, TANG Bing, HU Sheng, CHEN Yang, XI Yan

, Available online , doi: 10.15953/j.ctta.2022.015

Abstract(74) HTML PDF(14)

Abstract:
3D imaging technology that assists orthopaedic robot in preoperative planning can improve the accuracy and efficiency of surgery. However, at present, the traditional surgical navigation system based on 3D data requires preoperative drawing and image import manual registration, which makes the surgical procedure more cumbersome, and new errors may be introduced in the process of manual registration, resulting in the reduction of accuracy. To accomplish this demand, this paper proposes a remote device control service protocol (robolink) based on DICOM protocol, which can be used in operation and provides a new solution to the current problems. On the basis of supporting data transmission between two medical devices, motion control instructions can also be transmitted to achieve the effect of mutual cooperation between devices. According to the above design, the protocol is tested in the experimental environment of a shadow medical 3D C-arm and a simulated surgical robot. The results show that robolink protocol can effectively complete the tasks of data transmission and equipment control, and holds feasibility and security.

Research on Quadric Surface Fitting Algorithm Based on CT Data

FAN Zhixuan, QUE Jiemin, WEI Cunfeng, LIU Baodong, WEI Biao

, Available online , doi: 10.15953/j.ctta.2022.040

Abstract(76) HTML PDF(7)

Abstract:
Quadric surface is a kind of common workpiece shape in industry. It can be imaged by computed tomography (CT). In order to measure the internal quadric surface of an object, the object was scanned and its slices were reconstructed. We used U-net image segmentation network to obtain the interested region and then detected the edge of the segmentation results and got curve fitting results. The curves were stacked into a three-dimensional point set. The three-dimensional spatial coordinate information of internal quadric surface was computed through surface fitting. The results show that the proposed method can effectively extract the internal quadric surface parameters, and the fitting error can be controlled within 1%, which is superior to that of the traditional algorithm.

Clinicopathological and CT Findings of Cystic Lung Cancer

MENG Hongjia, CHEN Xiaojuan, HUANG Junjie, HE Xiaoxue, CHEN Huai

, Available online , doi: 10.15953/j.ctta.2022.014

Abstract(36) HTML PDF(1)

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Objective: Cystic lung cancer is a rare type of lung cancer with special morphological manifestations, which has not been fully recognized in imaging. This study aims to improve the understanding and diagnostic ability of this special type of lung cancer by analyzing its CT features and clinicopathology. Methods: The clinical information, pathological types and CT image characteristics of patients with cystic lung cancer diagnosed in our hospital from January 2015 to June 2021 were retrospectively summarized and analyzed. Results: There were 44 cases of adenocarcinoma (86.27％), including 7 cases of microinvasive adenocarcinoma (13.73%) and 35 cases of invasive adenocarcinoma (68.63%) (histological type: There were 11 cases (21.57%) of adjoint type, 8 cases (15.69%) of papillary type, and 15 cases (29.41%) of acinar type, among which 2 cases (3.92%) contained micropapillary components accounting for more than 20%, 1 case (1.96%) was not classified), and 1 case (1.96%) was pathologically suggested adenocarcinoma after chemotherapy. Lymph node biopsy in 1 case (1.96%) suggested metastatic lung adenocarcinoma. There were 5 cases of squamous cell carcinoma (9.80%), including 3 cases of keratinizing squamous cell carcinoma (5.89%) and 2 cases of non-keratinizing squamous cell carcinoma (3.92%). There was 1 case of large cell carcinoma (1.96%) and 1 case of high-grade mucoepidermoid carcinoma (1.96%). The peripheral distribution was mainly in 40 cases (80.30%). The mean diameter was (4.7± 2.7) cm. The main components were cystic cavity with ground glass in 20 cases (39.22%), cystic cavity with solid components in 22 cases (43.14%), cystic cavity with mixed components in 9 cases (17.65%). According to ario classification, 24 cases were type I (47.06%), 8 cases were type II (15.69%), type III 9 (17.65%), 10 cases were type IV (19.61%). The cyst wall was uneven in 42 cases (82.35%). There were 28 cases (54.90%) with lobular edge of the lesion and 14 cases (27.45%) with burr sign. There were 33 cases (64.71%) separated within the lesion and 36 cases (70.59%) with smooth inner wall. Relationship with the pleura: 24 cases (47.06%) of pleural traction, 11 cases (21.57%) of close pleura. Relationship with peripheral blood vessels: 8 cases (15.69%) of blood vessels passing through the lesion, 16 (31.37%) of blood vessels closely adhering to the edge of the lesion. The relationship with the surrounding bronchi: the bronchi passed through the lesion in 8 cases (15.69%), and moved towards the edge of the lesion in 21 cases (41.18%). Conclusion: The CT findings of cystic lung cancer have certain characteristics, and grasping its characteristics can make a suggestive diagnosis of lung cancer.

Combined Application of High Density Electrical Method and Transient Electromagnetic Method in Gobi Desert Area

TANG Su, WU Yinting, XING Hao, LOU Xuecong, SHI Haitao

, Available online , doi: 10.15953/j.ctta.2022.081

Abstract(87) HTML PDF(19)

Abstract:
This work is used for searching groundwater in a mineral concentration area by using geophysical exploration. Which includes high density electrical method and transient electromagnetic method. The purpose is to grasp the dynamic changes of groundwater resources accurately and support the sustainable development of ecological environment in desert Gobi area effectively. It is verified that the combination of high density electrical method and transient electromagnetic method guides the hydrological drilling construction in this area effectively. Which also provides a reference for the selection and application of geophysical exploration means under similar geological conditions.

Fast EPRI Imaging Based on 3MNet Denoising Network

QIAN Peizhang, QIAO Zhiwei, DU Congcong

, Available online , doi: 10.15953/j.ctta.2022.065

Abstract(140) HTML PDF(12)

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Electron Paramagnetic Resonance Imaging (EPRI) is an advanced technique for oxygen imaging. The current bottleneck in EPRI is the slow scanning speed, due to the fact that the projection signal at each angle needs to be repeated thousands of times to suppress random noise. One way to achieve fast scanning is to reduce the number of repeated acquisitions of the projection signal, however this in turn reduces the signal-to-noise ratio of the projection signal and results in a noisy reconstructed image. In order to effectively suppress the noise in the reconstructed image, this paper proposes a multi-channel, multi-scale, multi-concatenation, convolutional network (3MNet) based image denoising network to achieve high accuracy and fast EPRI imaging. The network consists of three sub-networks. The network consists of three sub-networks. The first sub-network is an attention-based convolutional network, whose output feature images are stitched with the input images to form the input of the back-end network; the second sub-network is a three-channel convolutional network; and the third sub-network is a multi-scale convolutional network. The experimental results show that the 3MNet network proposed in this paper can achieve high accuracy denoising of EPRI images and thus fast imaging.

Enhanced CT Texture Analysis and Machine Learning in the Differentiation between Adenolymphoma and Mixed Tumor of Parotid

MAO Xiaoxiao, MA Shusheng, LU Liang, SHI Jiugang, ZHANG Lei

, Available online , doi: 10.15953/j.ctta.2022.027

Abstract(62) HTML PDF(10)

Abstract:
Objective: To explore the application of enhanced CT texture analysis combined with machine learning in the differential diagnosis of parotid adenolymphoma and mixed tumor. Methods: 40 cases of parotid adenolymphoma and mixed tumor were retrospectively analyzed, including 21 cases of adenolymphoma and 19 cases of mixed tumor. The region of interest (ROI) chosen at axial enhanced-CT images of the tumor maximum cross section was performed using Mazda software. The optimal texture parameters were selected by four different methods : Fisher coefficient, probability of classification error and average correlation coefficients , mutual information and the combination of the above three methods. ROC curve analysis was used to evaluate diagnostic efficacy. Finally, the texture parameters were classified and analyzed in four machine learning ways: raw data analysis (RDA), principal component analysis (PCA), linear discriminant analysis (LDA) and nonlinear discriminant analysis (NDA), and analyzed the diagnostic efficiency of different classification algorithms. Results: In the texture feature parameters, WavEnHH_s-4, GrVariance, 45dgr_Fraction, WavEnLL_s-4, GrSkewness between adenolymphoma and mixed tumor were statistically significant. The ROC curve showed that WavEnLL_s-4 had a balance of sensitivity and specificity, the AUC value, sensitivity and specificity were 0.797, 84.2 and 62.5. The misclassification rate of NDA (5.0～12.5) was lower than that of any other kind of algorithms. The NDA of FPM had the lowest misclassification rate (5.0), Its Accuracy rate, sensitivity, specificity, prediction accuracy, positive predictive value, and negative prediction value are 95.0, 95.2, 94.7, 95.2, 94.7. Conclusion: The Optimum texture features based on enhanced CT were significantly different between parotid adenolymphoma and mixed tumor, FPM combined with NDA classification method has the lowest misclassification rate, which contributes to identify parotid adenolymphoma and mixed tumor.

Progress of Material Decomposition Algorithms in Image Domain of Dual-energy CT

GUO Qiao, YAO Xufeng

, Available online , doi: 10.15953/j.ctta.2021.067

Abstract(1201) HTML PDF(26)

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Spectral CT can produce basis materials with different X-ray energies, and the generated basis materials can be used for qualitative and quantitative evaluation of tissue components and contrast agent distribution, and its ability to separate and identify imaging materials is obviously superior to traditional single-energy CT. Dual-energy spectrum technology is one of the most commonly used modes in spectrum CT, which plays an important role in clinical application. In this paper, the decomposition methods of basis material in the image domain of dual-energy spectrum CT were classified into two categories: two-material decomposition and multi-material decomposition, and these methods were summarized. Finally, the trend of future development is also addressed.

Advances in Imaging Research on Prediction of Colorectal Cancer Gene Mutation Status

JIA Jianye, DING Cong, ZHOU Wei, BAI Genji

, Available online , doi: 10.15953/j.ctta.2022.028

Abstract(62) HTML PDF(5)

Abstract:
Clinicians are increasingly demanding personalized treatment strategies for patients with colorectal cancer (CRC), and it is particularly important to detect mutated gene profiles when CRC patients are diagnosed or metastatic. The effective prediction of genetic information of CRC patients by analyzing tumor biological characteristics through non-invasive imaging has become a research hotspot in this field. This review will focus on the application of different imaging methods to predict CRC gene mutation status.

Study on the Correlation Between CT Emphysema Volume and Small Shadow Intensity and Pneumoconiosis Lung Function

ZHAO Qiqi, FENG Li, LIU Yuquan, WANG Meifang

, Available online , doi: 10.15953/j.ctta.2021.049

Abstract(60) HTML PDF(4)

Abstract:
Objective: To compare the influence of emphysema and lung small shadow on lung function in patients with pneumoconiosis. Methods: 96 patients with pneumoconiosis complicated with emphysema admitted to Taihe Hospital of Shiyan city from 2015 to 2020 were selected. Chest CT examination and lung function measurement were performed. 64-slice spiral CT (GE Optima CT680) was used to quantitatively analyze the low attenuation volume (LAV%) of the whole lung, the left and right lungs, and the upper, middle and lower lobes of each lung, and according to LAV% of the whole lung, they were divided into group A: LAV%<15%, GROUP B: LAV% 15%～30%, group C: LAV%>30%, the small shadow density (SSD) of whole lung, left and right lung, upper, middle and lower lung field was obtained by applying the criteria for evaluating Small Shadow Density in chest radiographs to CT images, and the correlation between SSD and lung function was analyzed. Results: SSD of whole lung was negatively correlated with FEV1, TLC, PEF, MEF75%, MEF25%, and positively correlated with RV/TLC. LAV% was negatively correlated with FEV1, FEV1%, DLCO, PEF, MEF75%, MEF50%, MEF25% in whole lung, left lung, right lung, and upper, middle and lower lobe of each lung, but positively correlated with RV, RV/TLC%. When LAV%>30%, that is, the correlation between LAV% and lung function FEV1, FEV1%, DLCO, RV/TLC, PEF, MEF75%, MEF50%, MEF25% in group C was higher than that in group A and B. There is a certain correlation between the density of small shadows in lung and ventilation function and volume parameters, but a weak correlation between the density of small shadows and diffusion function. Conclusion: The degree of emphysema and small shadow intensity in patients with pneumoconiosis have a certain correlation with lung function, but the small shadow intensity of emphysema has a better correlation with lung function, and it can evaluate the degree of lung injury in patients with pneumoconiosis to a certain extent, which is worthy of clinical application.

The Value of CT in Predicting Central Lymph Node Metastasis of Papillary Thyroid Microcarcinoma

TIAN Jiangyu, TAN Zhiwei

, Available online , doi: 10.15953/j.1004-4140-2022.31.00.00

Abstract(98) HTML PDF(7)

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Objective: To determine the value of CT in predicting CLNM in PTMC. Methods: 157 patients with PTMC confirmed by pathology in our hospital were enrolled, and the CT and clinicopathological data of the patients were retrospectively analyzed. ROC curve is used to determine the optimal cutoff value of PTMC greatest diameter for CLNM. The binary logistic regression model of PTMC CLNM was established by CT and clinical pathological data, and the diagnostic value of the model was evaluated by ROC curve. Results: According to the ROC curve, the optimal cutoff value for predicting PTMC CLNM is 6mm. Univariate analysis: Cookie bite sign , microcalcification , multifocality , PTMC greastest diameter ≥6mm , male , Age<45 were risk factors for PTMC CLNM. Binary Logistic regression analysis: cookie bite sign with protruding (OR=5.159, 95%CI=1.137~23.400), multifocality (OR=2.734, 95%CI=1.215~6.154), PTMC greastest diameter ≥6mm (OR=3.259, 95%CI=1.326~8.008), male (OR=3.776, 95%CI=1.339~10.653), age <45 years (OR=3.222, 95%CI=1.419~7.777), were independent risk factors for PTMC CLNM. According to the ROC curve, when the Youden index=0.502, the sensitivity and specificity in predicting CLNM were 82.5% and 68.0%, respectively. Conclusion: The binary logistic regression model is helpful to predict PTMC CLNM. Cookie bite sign with protruding, PTMC greastest diameter≥6mm, male, and age<45 were independent risk factors for PTMC CLNM. For these patients, surgeons may consider central lymph node dissection.

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