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1.
J Cell Sci ; 136(22)2023 11 15.
Artigo em Inglês | MEDLINE | ID: mdl-37902031

RESUMO

Head rotation in human spermatozoa is essential for different swimming modes and fertilisation, as it links the molecular workings of the flagellar beat with sperm motion in three-dimensional (3D) space over time. Determining the direction of head rotation has been hindered by the symmetry and translucent nature of the sperm head, and by the fast 3D motion driven by the helical flagellar beat. Analysis has been mostly restricted to two-dimensional (2D) single focal plane image analysis, which enables tracking of head centre position but not tracking of head rotation. Despite the conserved helical beating of the human sperm flagellum, human sperm head rotation has been reported to be uni- or bi-directional, and even to intermittently change direction in a given cell. Here, we directly measure the head rotation of freely swimming human sperm using multi-plane 4D (3D+t) microscopy and show that: (1) 2D microscopy is unable to distinguish head rotation direction in human spermatozoa; (2) head rotation direction in non-capacitating and capacitating solutions, for both aqueous and viscous media, is counterclockwise (CCW), as seen from head to tail, in all rotating spermatozoa, regardless of the experimental conditions; and (3) head rotation is suppressed in 36% of spermatozoa swimming in non-capacitating viscous medium, although CCW rotation is recovered after incubation in capacitating conditions within the same viscous medium, possibly unveiling an unexplored aspect of the essential need of capacitation for fertilisation. Our observations show that the CCW head rotation in human sperm is conserved. It constitutes a robust and persistent helical driving mechanism that influences sperm navigation in 3D space over time, and thus is of critical importance in cell motility, propulsion of flagellated microorganisms, sperm motility assessments, human reproduction research, and self-organisation of flagellar beating patterns and swimming in 3D space.


Assuntos
Motilidade dos Espermatozoides , Natação , Humanos , Masculino , Sêmen , Espermatozoides , Cauda do Espermatozoide
2.
Artigo em Chinês | MEDLINE | ID: mdl-38802310

RESUMO

Objective: To select chest CT image patterns for the diagnosis of pneumoconiosis and establish a method for determining the profusion of circular small shadows in chest CT. Methods: In April 2021, 66 cases of occupational pneumoconiosis patients with digital radiography (DR) chest radiographs and chest CT imaging data with circular small shadow as the main manifestations were selected as the study objects. 1.5 mm and 5 mm chest CT axial images, 1 mm and 5 mm chest CT coronal multi-plane recombination (MPR) images, and 5 mm chest CT coronal maximum intensity projection (MIP) images were used to observe the different characteristics of pneumoconiosis patients, and were compared and analyzed with DR chest radiographs to establish the experimental chest CT standards. The consistency of the profusion results between the experimental chest CT standards and GBZ 70-2015 Diagnosis of Occupational Pneumoconiosis was verified. Results: All the 66 objects were male, including 33 cases of stage Ⅰ pneumoconiosis, 17 cases of stage Ⅱ pneumoconiosis and 16 cases of stage Ⅲ pneumoconiosis. By observing five chest CT images of 66 objects, we found that chest CT images of different modes could clearly display and identify abnormal images such as small circular shadow, large shadow, small shadow aggregation, honeycomb glass shadow, flake glass shadow, uniform low-profusion glass shadow, mesh glass shadow, cable shadow, linear shadow, subpleural spinous shadow, subpleural nodules, various kinds of emphysema and lung texture distortion and fracture. Small shadow aggregation was usually accompanied by the appearance of large shadow. The vascular shadows in 5 mm CT images had good ductility, and small nodules were easy to distinguish. The coronal MIP image of 5 mm chest CT used edge enhancement technology, which was prone to small shadow fusion and fibrotic shadow fusion. The coronal MPR image of 5 mm chest CT was highly consistent with the DR chest radiographs in terms of the integrity of film reading. GBZ 70-2015 standard was used to compare the profusion of DR chest radiographs and 5 mm chest CT coronal MPR images of 66 objects, and the consistency test Kappa=0.64. GBZ 70-2015 standard and experimental chest CT standard were used to compare the profusion results of DR chest radiographs and 5 mm chest CT coronal MPR images of 66 objects, respectively, and the consistency test Kappa=0.80, with high consistency. Conclusion: 5 mm coronal MPR image is suitable for chest CT imaging in the diagnosis of pneumoconiosis. Following the selection path and method of GBZ 70-2015 profusion criterion, the established experimental chest CT standard in determining the profusion of small circular shadows in 5 mm coronal MPR images of chest CT with pneumoconiosis has a high consistency with GBZ 70-2015 standard.


Assuntos
Pneumoconiose , Radiografia Torácica , Tomografia Computadorizada por Raios X , Humanos , Pneumoconiose/diagnóstico por imagem , Masculino , Tomografia Computadorizada por Raios X/métodos , Radiografia Torácica/métodos , Pessoa de Meia-Idade , Processamento de Imagem Assistida por Computador/métodos , Pulmão/diagnóstico por imagem , Idoso
3.
Echocardiography ; 39(1): 7-19, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34877695

RESUMO

OBJECTIVES: Right ventricular (RV) failure post left ventricular assist device (LVAD) implantation is associated with increased morbidity and mortality. A novel RV multi-plane imaging method using two-dimensional echocardiography and electronic plane rotation (MPE) was used to quantify RV function prior to LVAD implantation and to identify potential added value in this patient population. METHODS: In twenty-five end-stage heart failure patients (age 58.9 ± 6.8 years, 76% male), systolic function of four different RV walls (lateral, anterior, inferior and inferior coronal) were evaluated from one focussed apical view using MPE. RESULTS: Feasibility of tricuspid annular plane systolic excursion (TAPSE) and tricuspid annular peak systolic velocity (RV-S') measurements were high (84-100%), with lower TAPSE values measured in the inferior (14.2 ± 4.6 mm) and inferior coronal (12.3 ± 5.0 mm) walls compared to the lateral (16.3 ± 4.5 mm) and anterior walls (16.0 ± 4.5 mm). RV wall longitudinal strain (RV-LS) measurement was most feasible in the lateral wall (80%; mean: -12.1 ± 4.2%). TAPSE and RV-LS values were significantly reduced in patients compared to matched healthy individuals (p = <0.001). Seven (28%) patients who developed moderate to severe RV failure (RVF) early post-implant (≤30 days) had lower pre-implant values across all multi-plane parameters compared to those without significant post-implant RVF, notably four-wall averaged TAPSE (11.1 ± 3.4 mm vs 15.9 ± 4.0 mm; p = 0.02). CONCLUSION: 2D MPE was highly feasible for RV wall quantification pre-LVAD surgery, detecting differences in regional wall function. This novel method comprehensively quantifies RV wall function and could complement current pre-LVAD screening protocols.


Assuntos
Coração Auxiliar , Disfunção Ventricular Direita , Idoso , Ecocardiografia/métodos , Feminino , Ventrículos do Coração/diagnóstico por imagem , Humanos , Masculino , Pessoa de Meia-Idade , Função Ventricular Direita
4.
Sensors (Basel) ; 21(23)2021 Nov 25.
Artigo em Inglês | MEDLINE | ID: mdl-34883847

RESUMO

Shape reconstruction is growing as an important real-time monitoring strategy for applications that require rigorous control. Polymer optical fiber sensors (POF) have mechanical properties that allow the measurement of large curvatures, making them appropriate for shape sensing. They are also lightweight, compact and chemically stable, meaning they are easy to install and safer in risky environments. This paper presents a sensor system to detect angles in multiple planes using a POF-intensity-variation-based sensor and a procedure to detect the angular position in different planes. Simulations are performed to demonstrate the correlation between the sensor's mechanical bending response and their optical response. Cyclic flexion experiments are performed at three test frequencies to obtain the sensitivities and the calibration curves of the sensor at different angular positions of the lateral section. A Fast Fourier Transform (FFT) analysis is tested as a method to estimate angular velocities using POF sensors. The experimental results show that the prototype had high repeatability since its sensitivity was similar using different test frequencies at the same lateral section position. The proposed approach proved itself feasible considering that all linear calibration curves presented a coefficient of determination (R2) higher than 0.9.


Assuntos
Fibras Ópticas , Polímeros , Calibragem
5.
J Ultrasound Med ; 35(3): 651-9, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26903662

RESUMO

Intraductal sonography generates high-resolution images of the entire length of the biliary tree and peribiliary tissues, including 3-dimensional dual- and muti-plane reconstructions to depict complex anatomy. Portal cavernoma cholangiopathy (previously called portal biliopathy) can have multiple etiologies of obstructive cholestasis in the same patient, which can be difficult to define even with advanced imaging techniques.We describe 2 difficult cases of portal cavernoma cholangiopathy in which intraductal sonography helped in clinical management decisions. We think that intraductal sonography should be part of the standard management algorithm for patients with portal cavernoma cholangiopathy and describe the intraductal sonographic correlates of the cholangiographic changes in this condition.


Assuntos
Doenças dos Ductos Biliares/diagnóstico por imagem , Colestase/diagnóstico por imagem , Endossonografia/métodos , Hemangioma Cavernoso/diagnóstico por imagem , Adulto , Ductos Biliares Intra-Hepáticos/diagnóstico por imagem , Diagnóstico Diferencial , Humanos , Masculino
6.
Heliyon ; 10(5): e26645, 2024 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-38444471

RESUMO

The flagellar movement of the mammalian sperm plays a crucial role in fertilization. In the female reproductive tract, human spermatozoa undergo a process called capacitation which promotes changes in their motility. Only capacitated spermatozoa may be hyperactivated and only those that transition to hyperactivated motility are capable of fertilizing the egg. Hyperactivated motility is characterized by asymmetric flagellar bends of greater amplitude and lower frequency. Historically, clinical fertilization studies have used two-dimensional analysis to classify sperm motility, despite the inherently three-dimensional (3D) nature of sperm motion. Recent research has described several 3D beating features of sperm flagella. However, the 3D motility pattern of hyperactivated spermatozoa has not yet been characterized. One of the main challenges in classifying these patterns in 3D is the lack of a ground-truth reference, as it can be difficult to visually assess differences in flagellar beat patterns. Additionally, it is worth noting that only a relatively small proportion, approximately 10-20% of sperm incubated under capacitating conditions exhibit hyperactivated motility. In this work, we used a multifocal image acquisition system that can acquire, segment, and track sperm flagella in 3D+t. We developed a feature-based vector that describes the spatio-temporal flagellar sperm motility patterns by an envelope of ellipses. The classification results obtained using our 3D feature-based descriptors can serve as potential label for future work involving deep neural networks. By using the classification results as labels, it will be possible to train a deep neural network to automatically classify spermatozoa based on their 3D flagellar beating patterns. We demonstrated the effectiveness of the descriptors by applying them to a dataset of human sperm cells and showing that they can accurately differentiate between non-hyperactivated and hyperactivated 3D motility patterns of the sperm cells. This work contributes to the understanding of 3D flagellar hyperactive motility patterns and provides a framework for research in the fields of human and animal fertility.

7.
Bioinspir Biomim ; 19(1)2023 11 13.
Artigo em Inglês | MEDLINE | ID: mdl-37913552

RESUMO

This article presents a multimodal steerable earthworm-inspired soft robot based on vacuum and positive pressure powered pneumatic actuators capable of crawling both inside pipelines and on planar surfaces. The optimized modular vacuum pressure-driven actuator can generate deformation and anchoring motion through a unified structure under low vacuum pressure, giving it significant speed advantages and multi-modal locomotion capabilities. Meanwhile, the positive pressure powered actuator (PPPA) enables the robot to achieve controlled multi-directional and multi-degrees-of-freedom steering, moreover, enhances the consistency of the driving mechanism. The incorporation of front-end pressure sensing enables the robot to autonomously detect and evaluate pressure, facilitating automatic obstacle avoidance through the activation of corresponding turning units of PPPA. In the process of optimizing motion parameters, the overall motion efficiency has been improved by 16.7% by improving the control law. Through adjustments and optimizations of the interval time (cycle time), the robot is able to achieve a speed of 7.16 mm s-1during planar locomotion and 1.94 mm s-1during in-pipe locomotion. Using the developed robot, we conducted a series of turning experiments, including surface obstacle avoidance and cross-plane crawling, which demonstrated its enhanced capability in cross-plane steering and locomotion. Its related speed indicators showcase superior overall performance compared to other developed robots of the same type.


Assuntos
Oligoquetos , Robótica , Animais , Oligoquetos/fisiologia , Vácuo , Desenho de Equipamento , Locomoção/fisiologia
8.
Eur Heart J Imaging Methods Pract ; 1(2): qyad033, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-39045081

RESUMO

Aims: Advanced transthoracic echocardiography (TTE) using volumetric and deformational indices provides detailed quantification of right ventricular (RV) function in adults with congenital heart disease (ACHD). Two-dimensional multi-plane echocardiography (2D-MPE) has demonstrated regional wall differences in RV longitudinal strain (LS). This study aims to evaluate the association of these parameters with cardiovascular magnetic resonance (CMR). Methods and results: One-hundred stable ACHD patients with primarily affected RVs were included (age 50 ± 5 years; 53% male). Conventional and advanced echocardiographic RV functional parameters were compared with CMR-derived RV function. Advanced echocardiographic RV functional parameters were measurable in approximately one-half of the study cohort, while multi-wall LS assessment feasibility was lower. CMR RV ejection fraction (CMR-RVEF) was moderately correlated with deformational, area, and volumetric parameters [RV global LS (lateral wall and septum), n = 55: r = -0.62, P < 0.001; RV wall average LS, n = 34: r = -0.49, P = 0.002; RV lateral wall LS, n = 56: r = -0.45, P < 0.001; fractional area change, n = 67: r = 0.48, P < 0.001; 3D-RVEF, n = 48: r = 0.40, P = 0.005]. Conventional measurements such as TAPSE and RV S' correlated poorly. RV global LS best identified CMR-RVEF < 45% (area under the curve: 0.84, P < 0.001: cut-off value -19%: sensitivity 100%, specificity 57%). RVEF and LS values were significantly higher when measured by CMR compared with TTE (mean difference RVEF: 5 [-9 to 18] %; lateral (free) wall LS: -7 [7 to -21] %; RV global LS: -6 [5 to -16] %) while there was no association between respective LS values. Conclusion: In ACHD patients, advanced echocardiographic RV functional parameters are moderately correlated with CMR-RVEF, although significant differences exist between indices measurable by both modalities.

9.
Front Pediatr ; 11: 1085730, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36911028

RESUMO

Background and purpose: Electromechanical dyssynchrony, manifested by right bundle branch block and regional wall mechanical dysfunction, contributes to inefficient RV function in repaired Tetralogy of Fallot (ToF). This study aims to evaluate the synchronicity of multiple RV walls using two-dimensional multi-plane echocardiography (2D-MPE) in order to augment current understanding of the mechanisms behind RV dyssynchrony. Methods: Sixty-nine adult ToF patients [aged 33 (23-45) years; 61% male] and twenty-five matched healthy controls underwent deformational analysis of the RV lateral, anterior, inferior and septal walls following 2D-MPE acquisitions. RV synchronicity was assessed by the intra-RV deformation delay between each basal RV wall and mid-septal segment in addition to mechanical dispersion calculated across four, six and eight segments (MD). Results: All RV wall-septum delays plus MD-4 and MD-6 indices were significantly greater in ToF patients compared to healthy controls (p < 0.001-0.03). In ToF patients, the lateral and anterior RV walls were last to reach peak deformation and anterior wall longitudinal strain was lower (p = 0.001). Post systolic shortening of at least one RV wall segment was identified in 19 (28%) ToF patients. Despite similar ECG characteristics, lateral and anterior wall-septum delays were significantly longer in patients with greater degrees of dyssynchrony (73 [37-108]ms vs. 37 [0-63]ms, p = 0.006; 91 [52-116]ms vs. 41 [1-69]ms, p = 0.013), although RV ejection fraction (RVEF) was not significantly lower. MD-4 and MD-8 indices displayed moderate negative associations with RVEF, strengthened by inclusion of lateral wall longitudinal strain (r = 0.64/0.65; p ≤0.01). Conclusion: RV dyssynchrony in ToF is characterised by electromechanical delays between the lateral, anterior and septal walls, with anterior wall dysfunction likely associated with surgical repair of the RV outflow tract. Prospectively, 2D-MPE may have an emerging role evaluating RV mechanical response to electrical resynchronisation therapy.

10.
Acta Otolaryngol ; 142(7-8): 638-645, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36131531

RESUMO

BACKGROUND: Facial nerve schwannomas tend to be overlooked due to their mild early clinical presentation and slow progression. AIMS/OBJECTIVES: To describe the role of facial nerve reconstruction in guiding the diagnosis and treatment strategy of facial nerve schwannoma. MATERIAL AND METHODS: Multi-plane reformation (MPR) of the facial nerve was conducted to evaluate the facial nerve lesion segments, radiological characteristics, and mastoid decompression in 13 patients. RESULTS: Bone canal loss could be seen in lesions involving the geniculate ganglion and tympanic segment and those protruding toward the tympanum in two patients. Expansive space occupying lesions could be seen in the facial nerve involving the tympanic segment to the parotid segment in five patients. A 'trumpet mouth' spherical expansive space-occupying lesion centered in the mastoid segment and enlarged stylomastoid foramen could be seen in lesions involving the mastoid segment to the parotid segment in six patients. Treatment methods suitable for the patient were performed based on the facial palsy, tumor size, hearing loss, and social requirements. CONCLUSIONS AND SIGNIFICANCE: Facial nerve MPR reconstruction can comprehensively and intuitively display the lesion segment and area of the facial nerve in the temporal bone, estimate the facial nerve length, bone encapsulation, and mastoid decompression, and has characteristic presentations that can aid preliminary diagnosis and identification.


Assuntos
Neoplasias dos Nervos Cranianos , Paralisia Facial , Neurilemoma , Neoplasias dos Nervos Cranianos/diagnóstico por imagem , Neoplasias dos Nervos Cranianos/cirurgia , Nervo Facial/diagnóstico por imagem , Nervo Facial/patologia , Nervo Facial/cirurgia , Paralisia Facial/cirurgia , Humanos , Processamento de Imagem Assistida por Computador , Neurilemoma/diagnóstico por imagem , Neurilemoma/cirurgia
11.
Front Oncol ; 12: 971871, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36387085

RESUMO

Objectives: To propose a deep learning-based classification framework, which can carry out patient-level benign and malignant tumors classification according to the patient's multi-plane images and clinical information. Methods: A total of 430 cases of spinal tumor, including axial and sagittal plane images by MRI, of which 297 cases for training (14072 images), and 133 cases for testing (6161 images) were included. Based on the bipartite graph and attention learning, this study proposed a multi-plane attention learning framework, BgNet, for benign and malignant tumor diagnosis. In a bipartite graph structure, the tumor area in each plane is used as the vertex of the graph, and the matching between different planes is used as the edge of the graph. The tumor areas from different plane images are spliced at the input layer. And based on the convolutional neural network ResNet and visual attention learning model Swin-Transformer, this study proposed a feature fusion model named ResNetST for combining both global and local information to extract the correlation features of multiple planes. The proposed BgNet consists of five modules including a multi-plane fusion module based on the bipartite graph, input layer fusion module, feature layer fusion module, decision layer fusion module, and output module. These modules are respectively used for multi-level fusion of patient multi-plane image data to realize the comprehensive diagnosis of benign and malignant tumors at the patient level. Results: The accuracy (ACC: 79.7%) of the proposed BgNet with multi-plane was higher than that with a single plane, and higher than or equal to the four doctors' ACC (D1: 70.7%, p=0.219; D2: 54.1%, p<0.005; D3: 79.7%, p=0.006; D4: 72.9%, p=0.178). Moreover, the diagnostic accuracy and speed of doctors can be further improved with the aid of BgNet, the ACC of D1, D2, D3, and D4 improved by 4.5%, 21.8%, 0.8%, and 3.8%, respectively. Conclusions: The proposed deep learning framework BgNet can classify benign and malignant tumors effectively, and can help doctors improve their diagnostic efficiency and accuracy. The code is available at https://github.com/research-med/BgNet.

12.
Int J Cardiovasc Imaging ; 37(10): 2905-2915, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34008074

RESUMO

In patients with repaired Tetralogy of Fallot (ToF), detailed assessment of right ventricular (RV) function is important for management and timing of possible pulmonary valve re-intervention. The aim of this study was to evaluate RV function using two-dimensional multi-plane echocardiography (2D MPE), a novel four-wall imaging method obtained from one apical acoustic window utilising electronic plane rotation. In sixty-two ToF patients (aged - 28 [22, 39] years, 65% male), systolic function of four different RV walls (lateral, anterior, inferior and inferior coronal) were evaluated using MPE. Tricuspid annular plane systolic excursion (TAPSE), tricuspid annular peak systolic velocity (RV-S') and RV wall longitudinal strain (RV-LS) measurements were compared with those of matched healthy individuals. 2D MPE measurements were highly feasible across the four RV walls (93.5-100% for TAPSE/S'; 66.1-95.1% for RVLS) and could be performed more reliably than 3D RV ejection fraction (RVEF - 56.5%). All functional values were significantly reduced when compared to the control group (p < 0.001). Higher RV-LS values were seen in the lateral (- 17.8 ± 4.5%) and inferior (- 17.8 ± 4.2%) walls compared to the anterior (- 15.9 ± 3.8%) and inferior coronal (- 15.1 ± 3.9%) walls. 3D RVEF correlated strongest with RV-LS values from the lateral (r - 0.50; p = 0.002) and anterior walls (r - 0.74; p < 0.001) and furthermore the four-wall average (r - 0.57; p = 0.001). 2D MPE evaluation of the RV is highly feasible in ToF patients. This novel method provides new insights into regional RV wall function, enabling a more comprehensive and quantitative approach to RV assessment in daily clinical practice.


Assuntos
Tetralogia de Fallot , Disfunção Ventricular Direita , Adulto , Idoso , Ecocardiografia , Feminino , Ventrículos do Coração/diagnóstico por imagem , Humanos , Masculino , Valor Preditivo dos Testes , Volume Sistólico , Tetralogia de Fallot/diagnóstico por imagem , Tetralogia de Fallot/cirurgia , Disfunção Ventricular Direita/diagnóstico por imagem , Disfunção Ventricular Direita/etiologia , Função Ventricular Direita
13.
J Biophotonics ; 14(6): e202000499, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-33638313

RESUMO

In whole slide imaging (WSI), normally only a one layer imaging of the slide is performed. Autofocus at multiple positions is usually required. But defocus blur still exists due to tissue folding or specimen thickness. Repeated Z-stack scan be applied here, which, however, is too time consuming. Here, a high throughput slanted scanning WSI system is reported. In this system, the slide surface was slanted 1° relative to the focal plane. Thus, the focal plane spanned multiple layers of the sample. By moving the slide, multi-layer image data of the sample can be acquired simultaneously at a time frame comparable to conventional 1-layer imaging. With image fusion, defocus blur can be avoided. High quality and fast imaging of both cytological and histological slide specimens was demonstrated without applying aberration correction. The system can be a highly efficient way for the application of WSI in digital pathology.


Assuntos
Processamento de Imagem Assistida por Computador , Microscopia
14.
Comput Assist Surg (Abingdon) ; 22(sup1): 326-338, 2017 12.
Artigo em Inglês | MEDLINE | ID: mdl-29037075

RESUMO

Electrical impedance tomography (EIT) is a visual imaging technique for obtaining the conductivity and permittivity distributions in the domain of interest. As an advanced technique, EIT has the potential to be a valuable tool for continuously bedside monitoring of pulmonary function. The EIT applications in any three-dimensional (3 D) field are very limited to the 3 D effects, i.e. the distribution of electric field spreads far beyond the electrode plane. The 3 D effects can result in measurement errors and image distortion. An important way to overcome the 3 D effect is to use the multiple groups of sensors. The aim of this paper is to find the best space resolution of EIT image over various electrode planes and select an optimal plane spacing in a 3 D EIT sensor, and provide guidance for 3 D EIT electrodes placement in monitoring lung function. In simulation and experiment, several typical conductivity distribution models, such as one rod (central, midway and edge), two rods and three rods, are set at different plane spacings between the two electrode planes. A Tikhonov regularization algorithm is utilized for reconstructing the images; the relative error and the correlation coefficient are utilized for evaluating the image quality. Based on numerical simulation and experimental results, the image performance at different spacing conditions is evaluated. The results demonstrate that there exists an optimal plane spacing between the two electrode planes for 3 D EIT sensor. And then the selection of the optimal plane spacing between the electrode planes is suggested for the electrodes placement of multi-plane EIT sensor.


Assuntos
Simulação por Computador , Impedância Elétrica , Imageamento Tridimensional/métodos , Pulmão/diagnóstico por imagem , Tomografia Computadorizada por Raios X/métodos , Algoritmos , Humanos , Modelos Teóricos , Imagens de Fantasmas
15.
Eur J Sport Sci ; 14(6): 563-8, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24313829

RESUMO

Recent literature has related differences in pelvis-trunk coordination to low back pain (LBP) status. In addition, repetitive motions involving bending and twisting have been linked to high incidence of LBP. The purpose of this study was to examine trunk sagittal motion - axial rotation ('bend and twist') coordination during locomotion in three groups of runners classified by LBP status (LBP: current low back pain; RES: resolved low back pain and CTR: control group with no history of LBP). Trunk kinematic data were collected as running speed was systematically increased on a treadmill. Within-segment coordination between trunk sagittal and transverse planes of motion (trunk lean and axial rotation, respectively) was calculated using continuous relative phase (CRP), and coordination variability was defined as the between stride cycle standard deviation of CRP (CRPvar). Bend-twist coordination was more in-phase for the LBP group than CTR (p = 0.010) regardless of running speed. No differences in CRPvar were found between the groups. The results from our coordination (CRP) analysis were sensitive to LBP status and suggest that multi-plane interactions of the trunk should be considered in the assessment of LBP. This analysis also has potential for athletically oriented tasks that involve multi-plane interactions of the trunk, particularly ones that contain asymmetric action, such as sweep rowing or a shot on goal in field hockey or ice hockey.


Assuntos
Dor Lombar , Postura , Corrida/fisiologia , Tronco/fisiologia , Adolescente , Adulto , Fenômenos Biomecânicos , Marcha , Humanos , Pelve , Amplitude de Movimento Articular , Adulto Jovem
16.
Ultrasound Med Biol ; 39(8): 1337-42, 2013 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-23711502

RESUMO

Transesophageal echocardiography (TEE) is widely used for the evaluation of aortic arch atherosclerosis which carries an increased risk of ischemic stroke. We investigated the feasibility of simultaneous multi-plane imaging by real-time 3-D TEE for the assessment of aortic arch plaques. In 152 patients, we assessed aortic arch plaques and measured their maximum thickness by both conventional TEE imaging and multi-plane TEE imaging. There was excellent correlation and good agreement between the two methods in the measurement of the maximum thickness of arch plaques (r = 0.95, mean difference, -0.1 ± 0.5 mm). The mean image acquisition time required for aortic arch assessment by multi-plane imaging was significantly shorter than that required for conventional imaging in all patients (p < 0.001), especially those with complex plaques. These findings suggest that simultaneous multi-plane TEE imaging enables rapid and accurate evaluation of arch plaques and is therefore a useful tool for the assessment of aortic arch plaques in the clinical setting.


Assuntos
Aorta Torácica/diagnóstico por imagem , Doenças da Aorta/diagnóstico por imagem , Doenças da Aorta/epidemiologia , Aterosclerose/diagnóstico por imagem , Aterosclerose/epidemiologia , Ecocardiografia Transesofagiana/estatística & dados numéricos , Aumento da Imagem/métodos , Algoritmos , Ecocardiografia Transesofagiana/métodos , Feminino , Humanos , Interpretação de Imagem Assistida por Computador/métodos , Imageamento Tridimensional/métodos , Japão/epidemiologia , Masculino , Pessoa de Meia-Idade , Prevalência , Reprodutibilidade dos Testes , Medição de Risco , Sensibilidade e Especificidade
17.
Journal of Practical Radiology ; (12): 699-702, 2016.
Artigo em Chinês | WPRIM | ID: wpr-672265

RESUMO

Objective To investigate the feasibility of qualitative diagnosis of small pulmonary nodules (≤1 cm) using multi‐plane reconstruction (MPR) and volume rendering (VR) techniques based on spiral CT scan .Methods The CT images of 190 patients with small pulmonary nodules (≤1 cm) were analyzed retrospectively ,and compared the detection rates of several imaging features among different pathological types of nodules .Results In these 190 patients who were diagnosed as malignance by CT ,168 were confirmed by pathology with an accuracy rate of 88 .4% .The imaging features such as ground glass nodule ,vascular convergence in the benign group were significantly lower than those in the malignant group ,however the solid nodule was observed more frequently in the malignant group (P0 .05) .Except air bronchogram and vascular convergence ,some imaging features (pure ground glass nodule ,part solid ground glass nodule ,solid nodule) showed a decreasing trend ,whereas some others (speculation ,lobulation ,vacuole sign and pleural tag ) were increased among different pathological types of malignant nodules .The linear trend passed the significant test at 0 .017 level .Conclusion CT multi‐plane reconstruction (MPR) and volume rendering (VR) techniques can sufficiently demonstrate the malignant signs in small pulmonary nodules (≤1 cm ) ,can improve to identify different pathological types of such small pulmonary lesions .

18.
Artigo em Chinês | WPRIM | ID: wpr-437958

RESUMO

Objective To discuss the treatment effect of doctor-nurse cooperation in multi-plane operation of obstructive sleep apnea hypopnea syndrome.Methods 73 patients with multi-planar surgery due to OSAHS were divided into the observation group (38 cases) and the control group(35 cases) in our department from January 2008 to December 2012.Health care was strengthened throughout the course of treatment in the observation group and traditional treatment and care were adopted in the control group.Short-term and long-term efficacy,intraoperative and postoperative complications were compared between two groups.Results The operation of short-term effective rate was 100%,and significant differences were found in the long-term efficacy between the two groups.There were significant differences in nasal bleeding during surgery,one-time intubation success rate and the significances were found in postoperative pain,extubation time,lung infection and soft palate regurgitation between two groups.Conclusions The implementation of the multi-plane surgery for patients with OSAHS can effectively improve the short-term efficacy of the patients throughout the course of treatment.Strengthening doctor-nurse cooperation effectively improve the patients' long-term efficacy,reducing the patients' intraoperative and postoperative complications.

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