The Use of Video Imaging Techniques to Study Ultrafiltration and Blood Flow in the Normal and Diseased Kidney

Many non-invasive imaging techniques are available for the evaluation of patients with known or suspected coronary heart disease. Among these, computed-tomography-based techniques allow the quantification of coronary atherosclerotic calcium and non-invasive imaging of coronary arteries, whereas nuclear cardiology is the most widely used non-invasive approach for the assessment of myocardial perfusion. The available single-photon-emission computed tomography flow agents are characterised by a cardiac uptake proportional to myocardial blood flow. In addition, different positron emission tomography tracers may be used for the quantitative measurement of myocardial blood flow and coronary flow reserve. Extensive research is being performed in the development of non-invasive coronary angiography and myocardial perfusion imaging using cardiac magnetic resonance. Finally, new multimodality imaging systems have recently been developed bringing together anatomical and functional information. This article provides a description of the available non-invasive imaging techniques in the assessment of coronary anatomy and myocardial perfusion in patients with known or suspected coronary heart disease.

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Study on three-dimensional characteristics of natural ventilation in half-enclosed buildings using video imaging techniques

Journal of Wind Engineering and Industrial Aerodynamics ◽

10.1016/0167-6105(93)90359-v ◽

1993 ◽

Vol 46-47 ◽

pp. 831-836 ◽

Cited By ~ 1

Author(s):

M Ohba

Keyword(s):

Natural Ventilation ◽

Imaging Techniques ◽

Three Dimensional ◽

Video Imaging

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Video Imaging—a Computer Facilitated Approach to Communication and Planning in Orthognathic Surgery

British Journal of Orthodontics ◽

10.1179/bjo.20.3.187 ◽

1993 ◽

Vol 20 (3) ◽

pp. 187-191 ◽

Cited By ~ 8

Author(s):

David M. Sarver

Keyword(s):

Case Report ◽

Treatment Planning ◽

Orthognathic Surgery ◽

Imaging Techniques ◽

Video Image ◽

Video Imaging ◽

The Aesthetic

A case report is presented in order to illustrate the benefits of computerized video imaging in orthognathic surgery. It is suggested that superimposition of the cephalogram on the video image is helpful in treatment planning and in communication with the patient. Computerized video imaging techniques help clinicians and patients discuss the aesthetic impact of orthognathic surgery. The superimposition of the cephalogram and profile image, coupled with algorithmic predictions, allow the clinician to plan the surgery to closely match the desired result. This paper presents the planning and counselling of a patient using contemporary computerized video imaging techniques.

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Measurement of cerebrovascular reserve by multimodal imaging for cerebral arterial occlusion or stenosis patients: protocol of a prospective, randomized, controlled clinical study

Trials ◽

10.1186/s13063-019-3967-2 ◽

2020 ◽

Vol 21 (1) ◽

Author(s):

Zhi-peng Xiao ◽

ke Jin ◽

Jie-qing Wan ◽

Yong Lin ◽

Yao-hua Pan ◽

...

Keyword(s):

Clinical Trial ◽

Blood Flow ◽

Cerebral Blood Flow ◽

Ischemic Stroke ◽

Multimodal Imaging ◽

Imaging Techniques ◽

Trial Registry ◽

Clinical Trial Registry ◽

Cerebrovascular Reserve ◽

Randomized Controlled

Abstract Background Cerebrovascular reactivity (CVR) is the change in cerebral blood flow in response to a vaso-active stimulus, and may assist the treatment strategy of ischemic stroke. However, previous studies reported that a therapeutic strategy for stroke mainly depends on the degree of vascular stenosis with steady-state vascular parameters (e.g., cerebral blood flow and CVR). Hence, measurement of CVR by multimodal imaging techniques may improve the treatment of ischemic stroke. Methods/design This is a prospective, randomized, controlled clinical trial that aimed to examine the capability of multimodal imaging techniques for the evaluation of CVR to improve treatment of patients with ischemic stroke. A total of 66 eligible patients will be recruited from Renji Hospital, Shanghai Jiaotong University School of Medicine. The patients will be categorized based on CVR into two subgroups as follows: CVR > 10% group and CVR < 10% group. The patients will be randomly assigned to medical management, percutaneous transluminal angioplasty and stenting, and intracranial and extra-cranial bypass groups in a 1:1:1 ratio. The primary endpoint is all adverse events and ipsilateral stroke recurrence at 6, 12, and 24 months after management. The secondary outcomes include the CVR, the National Institute of Health stroke scale and the Modified Rankin Scale at 6, 12, and 24 months. Discussion Measurement of cerebrovascular reserve by multimodal image is recommended by most recent studies to guide the treatment of ischemic stroke, and thus its efficacy and evaluation accuracy need to be established in randomized controlled settings. This prospective, parallel, randomized, controlled registry study, together with other ongoing studies, should present more evidence for optimal individualized accurate treatment of ischemic stroke. Trial registration Chinese Clinical Trial Registry, ID: ChiCTR-IOR-16009635; Registered on 16 October 2016. All items are from the World Health Organization Trial Registration Data Set and registration in the Chinese Clinical Trial Registry: ChiCTR-IOR-16009635.

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4D flow MRI for non-invasive measurement of blood flow in the brain: A systematic review

Journal of Cerebral Blood Flow & Metabolism ◽

10.1177/0271678x20952014 ◽

2020 ◽

pp. 0271678X2095201

Author(s):

Alasdair G Morgan ◽

Michael J Thrippleton ◽

Joanna M Wardlaw ◽

Ian Marshall

Keyword(s):

Blood Flow ◽

Imaging Techniques ◽

Acquisition Time ◽

4D Flow ◽

Non Invasive ◽

Major Vessel ◽

Dynamic Velocity ◽

Blood Flow Dynamics ◽

Cerebrovascular Imaging

The brain’s vasculature is essential for brain health and its dysfunction contributes to the onset and development of many dementias and neurological disorders. While numerous in vivo imaging techniques exist to investigate cerebral haemodynamics in humans, phase-contrast magnetic resonance imaging (MRI) has emerged as a reliable, non-invasive method of quantifying blood flow within intracranial vessels. In recent years, an advanced form of this method, known as 4D flow, has been developed and utilised in patient studies, where its ability to capture complex blood flow dynamics within any major vessel across the acquired volume has proved effective in collecting large amounts of information in a single scan. While extremely promising as a method of examining the vascular system’s role in brain-related diseases, the collection of 4D data can be time-consuming, meaning data quality has to be traded off against the acquisition time. Here, we review the available literature to examine 4D flow’s capabilities in assessing physiological and pathological features of the cerebrovascular system. Emerging techniques such as dynamic velocity-encoding and advanced undersampling methods, combined with increasingly high-field MRI scanners, are likely to bring 4D flow to the forefront of cerebrovascular imaging studies in the years to come.

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A Systematic Review for the Design of In Vitro Flow Studies of the Carotid Artery Bifurcation

Cardiovascular Engineering and Technology ◽

10.1007/s13239-019-00448-9 ◽

2019 ◽

Vol 11 (2) ◽

pp. 111-127 ◽

Cited By ~ 1

Author(s):

A. M. Hoving ◽

E. E. de Vries ◽

J. Mikhal ◽

G. J. de Borst ◽

C. H. Slump

Keyword(s):

Blood Flow ◽

Carotid Artery ◽

Flow Visualization ◽

Design Process ◽

Imaging Technique ◽

Carotid Artery Disease ◽

Imaging Techniques ◽

Carotid Artery Bifurcation ◽

Flow Parameters

Abstract Purpose In vitro blood flow studies in carotid artery bifurcation models may contribute to understanding the influence of hemodynamics on carotid artery disease. However, the design of in vitro blood flow studies involves many steps and selection of imaging techniques, model materials, model design, and flow visualization parameters. Therefore, an overview of the possibilities and guidance for the design process is beneficial for researchers with less experience in flow studies. Methods A systematic search to in vitro flow studies in carotid artery bifurcation models aiming at quantification and detailed flow visualization of blood flow dynamics results in inclusion of 42 articles. Results Four categories of imaging techniques are distinguished: MRI, optical particle image velocimetry (PIV), ultrasound and miscellaneous techniques. Parameters for flow visualization are categorized into velocity, flow, shear-related, turbulent/disordered flow and other parameters. Model materials and design characteristics vary between study type. Conclusions A simplified three-step design process is proposed for better fitting and adequate match with the pertinent research question at hand and as guidance for less experienced flow study researchers. The three consecutive selection steps are: flow parameters, image modality, and model materials and designs. Model materials depend on the chosen imaging technique, whereas choice of flow parameters is independent from imaging technique and is therefore only determined by the goal of the study.

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Microcirculatory model predicts blood flow and autoregulation range in the human retina: in vivo investigation with laser speckle flowgraphy

AJP Heart and Circulatory Physiology ◽

10.1152/ajpheart.00404.2020 ◽

2020 ◽

Vol 319 (6) ◽

pp. H1253-H1273

Author(s):

Konstantinos Pappelis ◽

Lars Choritz ◽

Nomdo M. Jansonius

Keyword(s):

Blood Flow ◽

Healthy Subjects ◽

Imaging Techniques ◽

Physiological Model ◽

Laser Speckle ◽

Retinal Blood Flow ◽

Laser Speckle Flowgraphy ◽

New Approach ◽

Pressure Drops

We describe and test a new approach to quantify retinal blood flow, based on standard clinical examinations and imaging techniques, linked together with a physiological model. We use these findings to generate individualized estimates of the autoregulation range. We provide evidence that healthy subjects are closer to the lower autoregulation limit than thought before. This suggests that some retinas are less prepared to withstand hypoperfusion, even after small intraocular pressure rises or blood pressure drops.

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A method for creating precise low-cost landscape architecture simulations — combining computer-aided design with computer video-imaging techniques

Landscape and Urban Planning ◽

10.1016/0169-2046(92)90003-i ◽

1992 ◽

Vol 22 (1) ◽

pp. 11-16 ◽

Cited By ~ 9

Author(s):

Hai-Dong Shang

Keyword(s):

Computer Aided Design ◽

Landscape Architecture ◽

Imaging Techniques ◽

Low Cost ◽

Video Imaging ◽

Computer Aided ◽

Aided Design

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Acute Stroke Imaging Part I: Fundamentals

Canadian Journal of Neurological Sciences / Journal Canadien des Sciences Neurologiques ◽

10.1017/s0317167100009598 ◽

2010 ◽

Vol 37 (1) ◽

pp. 4-16 ◽

Cited By ~ 5

Author(s):

K. Butcher ◽

D. Emery

Keyword(s):

Blood Flow ◽

Acute Stroke ◽

Imaging Techniques ◽

Reperfusion Therapy ◽

Detection Sensitivity ◽

Prognostic Information ◽

Blood Flow Imaging ◽

Stroke Imaging ◽

Brain Parenchymal ◽

Contrast Ct

Neuroimaging is essential to stroke diagnosis and management. To date, the non-contrast CT has served as our main diagnostic tool. Although brain parenchymal changes visible on CT do provide valuable prognostic information, they provide limited insight into the potential for tissue salvage in response to reperfusion therapy, such as thrombolysis. Newer advanced CT and MRI based imaging techniques have increased the detection sensitivity for hyperacute and chronic parenchymal changes, including ischemia and hemorrhage, permit visualization of blood vessels and cerebral blood flow. This review outlines the basic principles underlying acquisition and interpretation of these newer imaging modalities in the setting of acute stroke. The utility of advanced brain parenchymal and blood flow imaging in the context of acute stroke patient management is also discussed. Part II in this series is a discussion of how these techniques can be used to rationally select appropriate patients for thrombolysis based on pathophysiological data.

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