scholarly journals Three-Dimensional Reconstruction Algorithm for CT Pulmonary Angiography in Patients with Pulmonary Embolism Combined with Syncope

2021 ◽  
Vol 2021 ◽  
pp. 1-8
Author(s):  
Zhongxing Zhang ◽  
Yan Zhang ◽  
Xiaohui Wang ◽  
Xiaoli Han ◽  
Xin Zhang ◽  
...  
Keyword(s):  
Pulmonary Embolism ◽  
3D Reconstruction ◽  
Clinical Characteristics ◽  
Three Dimensional ◽  
Reconstruction Algorithm ◽  
Pulmonary Angiography ◽  
Mesh Simplification ◽  
Ct Pulmonary Angiography ◽  
Dimensional Reconstruction ◽  
The Difference

This paper aimed to study the clinical characteristics of patients with pulmonary embolism (PE) with syncope (PE + S) based on the three-dimensional (3D) reconstruction algorithm in computed tomography (CT) pulmonary angiography (CTPA). In this study, 857 patients with acute PE (APE) who were treated in hospital were selected as the research objects and divided into syncope group (group S) and nonsyncope group (group NS). The 3D reconstruction marching cubes (3DR-MC) algorithm was compared with the traditional MC (T-MC) algorithm and the mesh simplification MC (MMS-MC) algorithm, and the results proved that the running time of the 3DR-MC algorithm on the platform was shorter than that of the other two algorithms. The incidence of syncope in group S in women was higher than that in group NS (51.7% vs. 38.2%). The incidence of syncope classified as high risk in group S was higher than that in group NS, and the mortality rate of pulmonary embolism patients with syncope was higher, and the difference was statistically significant (χ2 = 113.332, P < 0.05 ). The incidence of syncope in group S was higher than that in group NS (χ2 = 4.074, P < 0.05 ). In short, hypertension was an independent risk factor for syncope. PE + S patients could be diagnosed and treated as early as possible based on the clinical characteristics, so as to reduce the adverse consequences of misdiagnosis.

Pediatric Pulmonary Embolism: Diagnostic and Management Challenges

2016 ◽  
Vol 9 (1) ◽  
pp. 110-113 ◽  
Author(s):  
Christian Lilje ◽  
Aman Chauhan ◽  
Jason P. Turner ◽  
Thomas H. Carson ◽  
Maria C. Velez ◽  
...  
Keyword(s):  
Pulmonary Embolism ◽  
Functional Assessment ◽  
Rare Case ◽  
Three Dimensional ◽  
Massive Pulmonary Embolism ◽  
Pulmonary Angiography ◽  
Computed Tomography Pulmonary Angiography ◽  
Dimensional Reconstruction ◽  
Surgical Embolectomy ◽  
Prophylactic Anticoagulation

A rare case of massive pulmonary embolism is presented in an oligosymptomatic teenager with predisposing factors. Computed tomography pulmonary angiography supported by three-dimensional reconstruction was diagnostic. The embolus qualified as massive by conventional anatomical guidelines, but as low risk by more recent functional criteria. Functional assessment has complemented morphologic assessment for risk stratification in adult patients. Such evidence is scarce in pediatrics. The patient underwent surgical embolectomy, followed by prophylactic anticoagulation, without further events. Diagnostic and management challenges are discussed.

The Reconstruction for Han Dynasty Stone Images Based on Three-Dimensional Vision

2014 ◽  
Vol 556-562 ◽  
pp. 5009-5012
Author(s):  
Guang Dong Pan
Keyword(s):  
Mathematical Model ◽  
3D Reconstruction ◽  
Basic Principle ◽  
Projective Transformation ◽  
Three Dimensional ◽  
Reconstruction Algorithm ◽  
Han Dynasty ◽  
Dimensional Reconstruction ◽  
New Research ◽  
Three Dimensional Vision

Mainly studying the three-dimensional reconstruction for multiple Han Dynasty stone images, this paper proposes a 3D reconstruction algorithm based on two images. The author analyzes the basic principle of SIFT matching points detection according to Epipolar geometry constraints and projective transformation of images in 2D plane, and establishes mathematical model for the 3D reconstruction on foundation of sequence images. The feasibility of 3D reconstruction based on the sequence images is approved by simulation for three gray-scale Han Dynasty stone digital images which provides a new research way for identifying the feature of a target by the camera.

scholarly journals Computed Tomography Image under Three-Dimensional Reconstruction Algorithm Based in Diagnosis of Renal Tumors and Retroperitoneal Laparoscopic Partial Nephrectomy

2021 ◽  
Vol 2021 ◽  
pp. 1-9
Author(s):  
Haijie Zhang ◽  
Fu Yin ◽  
Liyang Yang ◽  
Anqi Qi ◽  
Weiwei Cui ◽  
...  
Keyword(s):  
Computed Tomography ◽  
3D Reconstruction ◽  
Partial Nephrectomy ◽  
Three Dimensional ◽  
Reconstruction Algorithm ◽  
Ct Images ◽  
Renal Tumors ◽  
Dimensional Reconstruction ◽  
Group A ◽  
Group B

This study was to explore the clinical application value of computed tomography (CT) images based on a three-dimensional (3D) reconstruction algorithm for laparoscopic partial nephrectomy (LPN) in patients with renal tumors. 30 cases of renal cell carcinoma (RCC) patients admitted to the hospital were selected as the research objects and were rolled into two groups using a random table method. The patients who received PLN under the three-dimensional reconstruction and laparoscopic technique were included in the experimental group (group A), and the patients who received LPN using CT images only were included in the control group (group B). In addition, the treatment results of the two groups of patients were compared and analyzed. Results. The effective rate of the established model was 93.3%; the total renal arteriovenous variability of group A (13.3%) was higher than that of group B (6.7%), and the operation time (131.5 ± 32.1 minutes) was much lower than that of group B (158.7 ± 36.2 minutes), showing statistical significance ( P  < 0.05). Conclusion. CT images based on 3D reconstruction algorithms had high clinical application value for LPN in patients with renal tumors, which could improve the efficiency and safety of LPN.

scholarly journals Study on 3D reconstruction techniques of rocket body model based on strain monitor

2021 ◽  
Vol 336 ◽  
pp. 02003
Author(s):  
Aihua Chen ◽  
Long Cao ◽  
Guowei Yan ◽  
Ze Xu
Keyword(s):  
3D Reconstruction ◽  
Three Dimensional ◽  
Reconstruction Algorithm ◽  
Maximum Error ◽  
Reconstruction Technique ◽  
Body Model ◽  
Strain Monitoring ◽  
Strain Data ◽  
Dimensional Reconstruction ◽  
Shape Characteristics

A three-dimensional reconstruction technique based on strain monitoring is proposed in this paper. According to the strain data of finite measuring points, the shape characteristics of the whole rocket structure are reconstructed, which provides the basis for the reliability judgment of the structure. Based on the theory of Ko, the 3D reconstruction algorithm for the rocket model of cylindrical structure is realized. The strain nephogram of plate model is simulated by ANASYS. And the strain nephogram is reconstructed by reconstruction algorithm, then compared with the simulation results. The results show that the maximum error between the results of reconstruction and simulation is 1.91%, which indicated that the agreement is great.

Three-dimensional Reconstruction of Microscopic Image Based on Multi-ST Algorithm

2020 ◽  
Vol 64 (2) ◽  
pp. 20506-1-20506-7
Author(s):  
Min Zhu ◽  
Rongfu Zhang ◽  
Pei Ma ◽  
Xuedian Zhang ◽  
Qi Guo
Keyword(s):  
3D Reconstruction ◽  
Three Dimensional ◽  
Scale Model ◽  
Microscopic Image ◽  
Multi Scale ◽  
Gaussian Pyramid ◽  
Cost Aggregation ◽  
Dimensional Reconstruction ◽  
Image Pairs ◽  
Accurate Matching

Abstract Three-dimensional (3D) reconstruction is extensively used in microscopic applications. Reducing excessive error points and achieving accurate matching of weak texture regions have been the classical challenges for 3D microscopic vision. A Multi-ST algorithm was proposed to improve matching accuracy. The process is performed in two main stages: scaled microscopic images and regularized cost aggregation. First, microscopic image pairs with different scales were extracted according to the Gaussian pyramid criterion. Second, a novel cost aggregation approach based on the regularized multi-scale model was implemented into all scales to obtain the final cost. To evaluate the performances of the proposed Multi-ST algorithm and compare different algorithms, seven groups of images from the Middlebury dataset and four groups of experimental images obtained by a binocular microscopic system were analyzed. Disparity maps and reconstruction maps generated by the proposed approach contained more information and fewer outliers or artifacts. Furthermore, 3D reconstruction of the plug gauges using the Multi-ST algorithm showed that the error was less than 0.025 mm.

A Systematic Review of Double Low-dose CT Pulmonary Angiography in Pulmonary Embolism

2019 ◽  
Vol 15 (5) ◽  
pp. 453-460 ◽  
Author(s):  
Sultan Aldosari ◽  
Zhonghua Sun
Keyword(s):  
Systematic Review ◽  
Pulmonary Embolism ◽  
Image Quality ◽  
Radiation Dose ◽  
Contrast Medium ◽  
Low Dose ◽  
Pulmonary Angiography ◽  
Ct Pulmonary Angiography ◽  
Low Contrast ◽  
Low Contrast Medium

Background: The aim of this study is to perform a systematic review of the feasibility and clinical application of double low-dose CT pulmonary angiography (CTPA) in the diagnosis of patients with suspected pulmonary embolism. Discussion: A total of 13 studies were found to meet selection criteria reporting both low radiation dose (70 or 80 kVp versus 100 or 120 kVp) and low contrast medium dose CTPA protocols. Lowdose CTPA resulted in radiation dose reduction from 29.6% to 87.5% in 12 studies (range: 0.4 to 23.5 mSv), while in one study, radiation dose was increased in the dual-energy CT group when compared to the standard 120 kVp group. CTPA with use of low contrast medium volume (range: 20 to 75 ml) was compared to standard CTPA (range: 50 to 101 ml) in 12 studies with reduction between 25 and 67%, while in the remaining study, low iodine concentration was used with 23% dose reduction achieved. Quantitative assessment of image quality (in terms of signal-to-noise ratio and contrast-to-noise ratio) showed that low-dose CTPA was associated with higher, lower and no change in image quality in 3, 3 and 6 studies, respectively when compared to the standard CTPA protocol. The subjective assessment indicated similar image quality in 11 studies between low-dose and standard CTPA groups, and improved image quality in 1 study with low-dose CTPA. Conclusion: This review shows that double low-dose CTPA is feasible in the diagnosis of pulmonary embolism with significant reductions in both radiation and contrast medium doses, without compromising diagnostic image quality.

scholarly journals COVID-19-induced vascular angiopathy: CTPA signs in critically ill patients other than acute pulmonary embolism and high-lung opacity scores

2021 ◽  
Vol 52 (1) ◽  
Author(s):  
Mohamed Hossameldin khalifa ◽  
Ahmed Samir ◽  
Ayman Ibrahim Baess ◽  
Sara Samy Hendawi
Keyword(s):  
Artificial Intelligence ◽  
Pulmonary Embolism ◽  
Lung Volume ◽  
Acute Pulmonary Embolism ◽  
Pulmonary Angiography ◽  
Vascular Tree ◽  
Ct Pulmonary Angiography ◽  
Artificial Intelligence System ◽  
Intelligence System ◽  
Severity Scores

Abstract Background Vascular angiopathy is suggested to be the major cause of silent hypoxia among COVID-19 patients without severe parenchymal involvement. However, pulmonologists and clinicians in intensive care units become confused when they encounter acute respiratory deterioration with neither severe parenchymal lung involvement nor acute pulmonary embolism. Other radiological vascular signs might solve this confusion. This study investigated other indirect vascular angiopathy signs on CT pulmonary angiography (CTPA) and involved a novel statistical analysis that was performed to determine the significance of associations between these signs and the CT opacity score of the pathological lung volume, which is calculated by an artificial intelligence system. Results The study was conducted retrospectively, during September and October 2020, on 73 patients with critical COVID-19 who were admitted to the ICU with progressive dyspnea and low O2 saturation on room air (PaO2 < 93%). They included 53 males and 20 females (73%:27%), and their age ranged from 18 to 88 years (mean ± SD=53.3 ± 13.5). CT-pulmonary angiography was performed for all patients, and an artificial intelligence system was utilized to quantitatively assess the diseased lung volume. The radiological data were analyzed by three expert consultant radiologists to reach consensus. A low CT opacity score (≤10) was found in 18 patients (24.7%), while a high CT opacity score (>10) was found in 55 patients (75.3%). Pulmonary embolism was found in 24 patients (32.9%); three of them had low CT opacity scores. Four other indirect vasculopathy CTPA signs were identified: (1) pulmonary vascular enlargement (57 patients—78.1%), (2) pulmonary hypertension (14 patients—19.2%), (3) vascular tree-in-bud pattern (10 patients—13.7%), and (4) pulmonary infarction (three patients—4.1%). There were no significant associations between these signs and the CT opacity score (0.3205–0.7551, all >0.05). Furthermore, both pulmonary vascular enlargement and the vascular tree-in-bud sign were found in patients without pulmonary embolism and low CT-severity scores (13/15–86.7% and 2/15–13.3%, respectively). Conclusion Pulmonary vascular enlargement or, less commonly, vascular tree-in-bud pattern are both indirect vascular angiopathy signs on CTPA that can explain the respiratory deterioration which complicates COVID-19 in the absence of severe parenchymal involvement or acute pulmonary embolism.

scholarly journals CT pulmonary angiography in COVID-19 pneumonia: relationship between pulmonary embolism and disease severity

2021 ◽  
Vol 52 (1) ◽  
Author(s):  
Aya Yassin ◽  
Maryam Ali Abdelkader ◽  
Rehab M. Mohammed ◽  
Ahmed M. Osman
Keyword(s):  
Pulmonary Embolism ◽  
Disease Severity ◽  
Laboratory Data ◽  
Pulmonary Angiography ◽  
Significant Relation ◽  
Ct Pulmonary Angiography ◽  
Laboratory Results ◽  
Severity Of The Disease ◽  
The Relationship ◽  
D Dimer

Abstract Background Pulmonary embolism (PE) is one of the known sequels of COVID-19 infection. We aimed to assess the incidence of PE in patients with COVID-19 infection and to evaluate the relationship between the CT severity of the disease and the laboratory indicators. This was a retrospective study conducted on 96 patients with COVID-19 infection proved by positive PCR who underwent CT pulmonary angiography (CTPA) with a calculation of the CT severity of COVID-19 infection. Available patients’ complaint and laboratory data at the time of CTPA were correlated with PE presence and disease severity. Results Forty patients (41.7%) showed positive PE with the median time for the incidence of PE which was 12 days after onset of the disease. No significant correlation was found between the incidence of PE and the patients’ age, sex, laboratory results, and the CT severity of COVID-19. A statistically significant relation was found between the incidence of PE and the patients’ desaturation, hemoptysis, and chest pain. A highly significant correlation was found between the incidence of PE and the rising in the D-dimer level as well as the progressive CT findings when compared to the previous one. Conclusion CT progression and the rising in D-dimer level are considered the most important parameters suggesting underlying PE in patients with positive COVID-19 infection which is commonly seen during the second week of infection and alert the use of CT pulmonary angiography to exclude or confirm PE. This is may help in improving the management of COVID-19 infection.

scholarly journals Online Measurement of Deposit Surface in Electron Beam Freeform Fabrication

Sensors ◽  
2019 ◽  
Vol 19 (18) ◽  
pp. 4001 ◽  
Author(s):  
Shuhe Chang ◽  
Haoyu Zhang ◽  
Haiying Xu ◽  
Xinghua Sang ◽  
Li Wang ◽  
...  
Keyword(s):  
Electron Beam ◽  
3D Reconstruction ◽  
Three Dimensional ◽  
Thermal Conditions ◽  
Online Measurement ◽  
Three Dimensional Reconstruction ◽  
Continuous Change ◽  
Position Information ◽  
Freeform Fabrication ◽  
Dimensional Reconstruction

In the process of electron beam freeform fabrication (EBF3), due to the continuous change of thermal conditions and variability in wire feeding in the deposition process, geometric deviations are generated in the deposition of each layer. In order to prevent the layer-by-layer accumulation of the deviation, it is necessary to perform online geometry measurement for each deposition layer, based on which the error compensation can be done for the previous deposition layer in the next deposition layer. However, the traditional three-dimensional reconstruction method that employs structured laser cannot meet the requirements of long-term stable operation in the manufacturing process of EBF3. Therefore, this paper proposes a method to measure the deposit surfaces based on the position information of electron beam speckle, in which an electron beam is used to bombard the surface of the deposit to generate the speckle. Based on the structured information of the electron beam in the vacuum chamber, the three-dimensional reconstruction of the surface of the deposited parts is realized without need of additional structured laser sensor. In order to improve the detection accuracy, the detection error is theoretically analyzed and compensated. The absolute error after compensation is smaller than 0.1 mm, and the precision can reach 0.1%, which satisfies the requirements of 3D reconstruction of the deposited parts. An online measurement system is built for the surface of deposited parts in the process of electron beam freeform fabrication, which realizes the online 3D reconstruction of the surface of the deposited layer. In addition, in order to improve the detection stability of the whole system, the image processing algorithm suitable for this scene is designed. The reliability and speed of the algorithm are improved by ROI extraction, threshold segmentation, and expansion corrosion. In addition, the speckle size information can also reflect the thermal conditions of the surface of the deposited parts. Hence, it can be used for online detection of defects such as infusion and voids.

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