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Article: Simultaneous Biplane High Speed 1000 fps X-ray Angiography (HSAngio).

Nagesh, S V Setlur / Shields, A / Wu, X / Ionita, C / Bednarek, D R / Rudin, S

Proceedings of SPIE--the International Society for Optical Engineering

2022 Volume 12031

Abstract: High-speed 1000-fps x-ray Angiography (HSAngio) images can be used to visualize blood-flow patterns and derive flow velocities during neurointerventional procedures. In this work, we present for the very first-time, orthogonal views of contrast injection ...

Abstract	High-speed 1000-fps x-ray Angiography (HSAngio) images can be used to visualize blood-flow patterns and derive flow velocities during neurointerventional procedures. In this work, we present for the very first-time, orthogonal views of contrast injection in an aneurysm model acquired simultaneously using biplane HSAngio imaging. 3-D printed in-vitro models A and B of two different internal carotid-artery aneurysms were connected to a flow loop (circulation fluid: 60% water, 40% glycerol solution, circulation flow rate: 8 L/s). An automatic programmable injector (KD Scientific Legato 110) injected iodine contrast agent at a rate of 88 mL/min for a duration of 3 sec. With an RQA5 spectrum, 1000 fps HSAngio sequences of the contrast injection were acquired simultaneously on the frontal plane using the Actaeon detector (Direct Conversion, Stockholm) and on the lateral plane using the Aries (Direct Conversion, Stockholm) detector. The start of contrast injection and simultaneous biplane x-ray exposures and detector image acquisitions were manually synchronized to capture the initial inflow of contrast into the aneurysm region. For model A the frontal plane images gave a better visualization of the flow streamlines in the parent artery in the inflow (average velocity 28 cm/s) and outflow (average velocity 24 cm/s) region of the aneurysm. The vortices within the aneurysm region especially within the aneurysm dome were better visualized in the lateral plane images (average velocity 27 cm/s). Biplane HSAngio imaging techniques can give more accurate representations of 3-D blood flow within the complex vascular pathology of the human brain, compared to single-plane imaging.
Language	English
Publishing date	2022-04-04
Publishing country	United States
Document type	Journal Article
ISSN	0277-786X
ISSN	0277-786X
DOI	10.1117/12.2611554
Database	MEDical Literature Analysis and Retrieval System OnLINE

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Article: Use of 1000fps High Speed X-ray Angiography (HSAngio) to quantify differences in flow diversion effects of three stents with different coverage densities in a cerebral aneurysm invitro model.

Nagesh, S V Setlur / Shields, A / Wu, X / Ionita, C / Bednarek, D R / Rudin, S

Proceedings of SPIE--the International Society for Optical Engineering

2022 Volume 12031

Abstract: High temporal resolution images acquired using 1000fps HSAngio can be used to visualize blood flow patterns and derive flow velocities during neurointerventional procedures. In this work we use this technology to quantify the changes in the blood flow ... ...

Abstract	High temporal resolution images acquired using 1000fps HSAngio can be used to visualize blood flow patterns and derive flow velocities during neurointerventional procedures. In this work we use this technology to quantify the changes in the blood flow velocities inside a cerebral aneurysm after treatment with three different stents with varying degrees of metal coverage density; stent A : <2%, stent B: 23% and stent C: 40%. A 3D printed in-vitro model of internal carotid artery aneurysm was connected to a flow loop (60% water, 40% glycerol solution used as circulation fluid, circulation flow rate 8 L/s). An automatic programmable injector (KD Scientific Legato 110) was used to inject iodine contrast agent at a rate of 88 mL/min in 3secs. 1000 fps HSAngio sequences of the contrast injection were acquired using an Aries single photon counting detector (Direct Conversion Inc., Stockholm). From these images blood flow velocities were calculated using an optical flow algorithm. As expected the biggest reduction in blood flow velocity inside the aneurysm was 32.4% after deployment of stent C. However, the velocity profile distribution indicated there was still a significant inflow jet into the aneurysm which could be caused by a endoluminal leak between the stent and the vessel wall. The average reduction was only 14% after placement of stent B and 3% after placement of stent A. Blood velocity distribution maps derived using 1000fps HSAngiography technology can be used to evaluate the quality of flow diversion within the aneurysm after placement of stent. Critical information such as endo luminal leakage which can cause treatment failure can also be detected.
Language	English
Publishing date	2022-04-04
Publishing country	United States
Document type	Journal Article
ISSN	0277-786X
ISSN	0277-786X
DOI	10.1117/12.2611754
Database	MEDical Literature Analysis and Retrieval System OnLINE

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Article: Derivation of vascular wall shear stress from 1000 fps high-speed angiography (HSA) velocity distributions.

Shields, A / Setlur Nagesh, S V / Chivukula, V / Ionita, C / Bednarek, D R / Rudin, S

Proceedings of SPIE--the International Society for Optical Engineering

2022 Volume 12036

Abstract: Pathological changes in blood flow lead to altered hemodynamic forces, which are responsible for a number of conditions related to the remodeling and regeneration of the vasculature. More specifically, wall shear stress (WSS) has been shown to be a ... ...

Abstract	Pathological changes in blood flow lead to altered hemodynamic forces, which are responsible for a number of conditions related to the remodeling and regeneration of the vasculature. More specifically, wall shear stress (WSS) has been shown to be a significant hemodynamic parameter with respect to aneurysm growth and rupture, as well as plaque activation leading to increased risk of stroke. In-vivo measurement of shear stress is difficult due to the stringent requirements on spatial resolution near the wall boundaries, as well as the deviation from the commonly assumed parabolic flow behavior at the wall. In this work, we propose an experimental method of in-vitro WSS calculations from high-temporal resolution velocity distributions, which are derived from 1000 fps high-speed angiography (HSA). The high-spatial and temporal resolution of our HSA detector makes such high-resolution velocity gradient measurements feasible. Presented here is the methodology for calculation of WSS in the imaging plane, as well as initial results for a variety of vascular geometries at physiologically realistic flow rates. Further, the effect of spatial resolution on the gradient calculation is explored using CFD-derived velocity data. Such angiographic-based analysis with HSA has the potential to provide critical hemodynamic feedback in an interventional setting, with the overarching objective of supporting clinical decision-making and improving patient outcomes.
Language	English
Publishing date	2022-04-04
Publishing country	United States
Document type	Journal Article
ISSN	0277-786X
ISSN	0277-786X
DOI	10.1117/12.2611175
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Article: Investigating Angiographic Injection Parameters for Cerebral Aneurysm Hemodynamic Characterization Using Patient-Specific Simulated Angiograms.

White, R / Shields, A / Nagesh, S V / Smith, E / Davies, J / Bednarek, D R / Rudin, S / Ionita, C / Chivukula, V

Proceedings of SPIE--the International Society for Optical Engineering

2023 Volume 12468

Abstract: Cerebral aneurysm (CA) rupture is one of the major causes of hemorrhagic stroke. During endovascular therapy (ET), neurointerventionalists rely on qualitative image sequences and do not have access to crucial quantitative hemodynamic information. ... ...

Abstract	Cerebral aneurysm (CA) rupture is one of the major causes of hemorrhagic stroke. During endovascular therapy (ET), neurointerventionalists rely on qualitative image sequences and do not have access to crucial quantitative hemodynamic information. Quantifying angiographic image sequences can provide vital information, but it is not possible to perform this in a controlled manner in vivo. Computational fluid dynamics (CFD) is a valuable tool capable of providing high fidelity quantitative data by replicating the blood flow physics within the cerebrovasculature. In this work, we use simulated angiograms (SA) to quantify the hemodynamic interaction with a clinically utilized contrast agent. SA enables extraction of time density curves (TDC) within the desired region of interest to analyze hemodynamic parameters such as time to peak (TTP) and mean transit time (MTT) within the aneurysm. We present on the quantification of several hemodynamic parameters of interest for multiple, clinically-relevant scenarios such as variable contrast injection duration and bolus volumes for 7 patient-specific CA geometries. Results indicate that utilizing these analyses provides valuable hemodynamic information relating vascular and aneurysm morphology, contrast flow conditions and injection variability. The injected contrast circulates for multiple cardiac cycles within the aneurysmal region, especially for larger aneurysms and tortuous vasculature. The SA approach enables determination of angiographic parameters for each scenario. Together, these have the potential to overcome the existing barriers in quantifying angiographic procedures in vitro or in vivo, and can provide clinically valuable hemodynamic insights for CA treatment.
Language	English
Publishing date	2023-04-10
Publishing country	United States
Document type	Journal Article
ISSN	0277-786X
ISSN	0277-786X
DOI	10.1117/12.2653871
Database	MEDical Literature Analysis and Retrieval System OnLINE

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Article: Multi-angled simultaneous biplane High-Speed Angiography (HSA) of patient-specific 3D-printed aneurysm phantoms using 1000 fps CdTe Photon-Counting Detectors (PCD's).

Vanderbilt, E / Wu, X / Shields, A / Setlur Nagesh, S V / Ionita, C / Bednarek, D R / Rudin, S

Proceedings of SPIE--the International Society for Optical Engineering

2023 Volume 12468

Abstract: 1000 fps HSA enables visualization of flow details, which may be important in accurately guiding interventional procedures; however, single-plane imaging may lack clear visualization of vessel geometry and flow detail. The previously presented high-speed ...

Abstract	1000 fps HSA enables visualization of flow details, which may be important in accurately guiding interventional procedures; however, single-plane imaging may lack clear visualization of vessel geometry and flow detail. The previously presented high-speed orthogonal biplane imaging may overcome these limitations but may still result in foreshortening of vessel morphology. In certain morphologies, acquiring two non-orthogonal biplane projections at multiple angles can provide better flow detail rather than a standard orthogonal biplane acquisition. Flow studies of aneurysm models were performed, where simultaneous biplane acquisitions at various angles separating the two detector views allowed for better evaluation of morphology and flow. 3D-printed, patient-specific internal carotid artery aneurysm models were imaged with various non-orthogonal angles between the two high-speed photon-counting detectors (7.5 cm x 5 cm FOV) to provide frame-correlated simultaneous 1000-fps image sequences. Fluid dynamics were visualized in multi-angled planes of each model using automated injections of iodine contrast media. The resulting dual simultaneous frame-correlated 1000-fps acquisitions from multiple planes of each aneurysm model provided improved visualization of complex aneurysm geometries and flow streamlines. Multi-angled biplane acquisitions with frame correlation allows for further understanding of aneurysm morphology and flow details: additionally, the ability to recover fluid dynamics at depth enables accurate analysis of 3D flow streamlines, and it is expected that multiple-planar views will enable better volumetric flow visualization and quantification. Such better visualization has the potential to improve interventional procedures.
Language	English
Publishing date	2023-04-10
Publishing country	United States
Document type	Journal Article
ISSN	0277-786X
ISSN	0277-786X
DOI	10.1117/12.2653136
Database	MEDical Literature Analysis and Retrieval System OnLINE

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Article: Determining 3D Distributions of Pulsatile Blood Flow Using Orthogonal Simultaneous Biplane High-Speed Angiography (SB-HSA) with 1000 fps CdTe Photon Counting Detectors for 3D X-ray Particle Image Velocimetry (3D-XPIV) compared to Results Using Computational Fluid Dynamics (CFD).

Simon Wu, X / Shields, A / Vanderbilt, E / Setlur Nagesh, S V / Ionita, C / Bednarek, D R / Rudin, S

Proceedings of SPIE--the International Society for Optical Engineering

2023 Volume 12468

Abstract: 3D hemodynamic distributions are useful for the diagnosis and treatment of aneurysms. Detailed blood-flow patterns and derived velocity maps can be obtained using 1000 fps High Speed Angiography (HSA). The novel orthogonal Simultaneous Biplane High-Speed ...

Abstract	3D hemodynamic distributions are useful for the diagnosis and treatment of aneurysms. Detailed blood-flow patterns and derived velocity maps can be obtained using 1000 fps High Speed Angiography (HSA). The novel orthogonal Simultaneous Biplane High-Speed Angiography (SB-HSA) system enables flow information to be quantified in multiple planes, and with additional components of flow at depth, accurate 3D flow distributions are available. Computational Fluid Dynamics (CFD) is the current standard for derivation of volumetric flow distributions, but obtaining solution convergence is computationally expensive and time intensive. More importantly, matching in-vivo boundary conditions is non-trivial. Therefore, an experimentally derived 3D flow distribution method could offer realistic results with less computation time. Using SB-HSA image sequences, 3D X-Ray Particle Image Velocimetry (3D-XPIV) was explored as a new method for assessing 3D flow. 3D-XPIV was demonstrated using an in-vitro setup, where a patient-specific internal carotid artery aneurysm model was attached to a flow loop, and an automated injection of iodinated microspheres was used as a flow tracer. Two 1000 fps photon-counting detectors were placed orthogonally with the aneurysm model in the FOV of both planes. Frame-synchronization of the two detectors made correlation of single-particle velocity components at a given timepoint possible. With frame-rates of 1000 fps, small particle displacements between frames resolved realistic time varying flow, where accurate velocity distributions depended on near-instantaneous velocities. 3D-XPIV velocity distributions were compared to CFD velocity distributions, where the simulation boundary conditions matched the in-vitro setup. Results showed similar velocity distributions between CFD and 3D-XPIV.
Language	English
Publishing date	2023-04-10
Publishing country	United States
Document type	Journal Article
ISSN	0277-786X
ISSN	0277-786X
DOI	10.1117/12.2653617
Database	MEDical Literature Analysis and Retrieval System OnLINE

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Article ; Online: Effects of DNA extraction methods on the real time PCR quantification of Campylobacter jejuni, Campylobacter coli, and Campylobacter lari in chicken feces and ceca contents.

Dawson, Paul / Buyukyavuz, Ahmet / Ionita, Claudia / Northcutt, Julie

Poultry science

2022 Volume 102, Issue 2, Page(s) 102369

Abstract: Polymerase chain reaction (PCR) method was coupled with a DNA extraction to enumerate Campylobacter spp. from poultry gastrointestinal tract samples. Three experiments were conducted that included: 1) Development of a DNA standard curve related to ... ...

Abstract	Polymerase chain reaction (PCR) method was coupled with a DNA extraction to enumerate Campylobacter spp. from poultry gastrointestinal tract samples. Three experiments were conducted that included: 1) Development of a DNA standard curve related to bacterial DNA primers; 2) Design of a cell/genomic DNA extraction protocol to isolate Campylobacter spp. DNA from complex samples such as poultry feces; and 3) Comparison of PCR quantification to standard plate count methodology. The standard curve using primers for Campylobacter spp. was created for DNA extracted from environmental isolates with a linear range (R
MeSH term(s)	Animals ; Swine ; Campylobacter jejuni/genetics ; Campylobacter coli/genetics ; Campylobacter lari/genetics ; Chickens/genetics ; Real-Time Polymerase Chain Reaction/veterinary ; DNA, Bacterial/genetics ; DNA, Bacterial/analysis ; Campylobacter ; Campylobacter Infections/veterinary ; Campylobacter Infections/microbiology ; Poultry/genetics ; DNA Primers/genetics ; Feces/chemistry ; Swine Diseases
Chemical Substances	DNA, Bacterial ; DNA Primers
Language	English
Publishing date	2022-12-06
Publishing country	England
Document type	Journal Article
ZDB-ID	242586-5
ISSN	1525-3171 ; 0032-5791
ISSN (online)	1525-3171
ISSN	0032-5791
DOI	10.1016/j.psj.2022.102369
Database	MEDical Literature Analysis and Retrieval System OnLINE

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Article: Evaluation of methods to derive blood flow velocity from 1000 fps high-speed angiographic sequences (HSA) using optical flow (OF) and computational fluid dynamics (CFD).

Shields, A / Nagesh, S V Setlur / Ionita, C / Bednarek, D R / Rudin, S

Proceedings of SPIE--the International Society for Optical Engineering

2021 Volume 11595

Abstract: Digital Subtraction Angiography (DSA) is considered the gold standard for imaging and guiding treatment of neurovascular lesions, such as cerebral aneurysms and carotid stenoses. Though DSA can show high-resolution morphology, it remains difficult to ... ...

Abstract	Digital Subtraction Angiography (DSA) is considered the gold standard for imaging and guiding treatment of neurovascular lesions, such as cerebral aneurysms and carotid stenoses. Though DSA can show high-resolution morphology, it remains difficult to extract temporal physiological information, because higher frame-rates are necessary to accurately quantify neurovascular flow details. Recent advances in photon-counting detector technology have led us to develop High-Speed Angiography (HSA), where X-ray images are acquired at 1000 fps for more accurate visualization and quantification of blood flow. Blood flow was imaged using HSA under constant flow conditions within various 3D printed patient-specific phantoms. Blood velocity was quantified using an open source Optical Flow algorithm, OpenOpticalFlow, to perform velocity estimation based on the spatio-temporal intensity changes of iodinated contrast wavefronts. The results of these algorithms are then compared with Computational Fluid Dynamics (CFD) simulations, using the same inlet boundary conditions and model geometries. The performance of these algorithms at lower temporal resolution was then also assessed by simulating lower frame rates from the acquired 1000 fps data. It is important to ascertain the hemodynamic effect of abnormal neurovascular conditions, as well as their effect on treatment of such conditions during the actual clinical interventional procedure. While theoretical CFD results requiring considerable computer capability are delayed for hours or more, it is expected that clinical results from multiple HSA sequences will be available almost immediately while the patient is still under treatment, and even right after flow conditions are changed beneficially by the intervention.
Language	English
Publishing date	2021-02-15
Publishing country	United States
Document type	Journal Article
ISSN	0277-786X
ISSN	0277-786X
DOI	10.1117/12.2580881
Database	MEDical Literature Analysis and Retrieval System OnLINE

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Article: Characterization of velocity patterns produced by pulsatile and constant flows using 1000 fps high-speed angiography (HSA).

Shields, A / Setlur Nagesh, S V / Ionita, C / Bednarek, D R / Rudin, S

Proceedings of SPIE--the International Society for Optical Engineering

2021 Volume 11600

Abstract: In order to accurately quantify rapidly changing blood flow velocities, as typically seen in the neurovasculature, high temporal resolution is necessary. Current methods to extract velocity data from angiographic image sequences are generally limited to ... ...

Abstract	In order to accurately quantify rapidly changing blood flow velocities, as typically seen in the neurovasculature, high temporal resolution is necessary. Current methods to extract velocity data from angiographic image sequences are generally limited to 30 fps or less. High-speed angiography (HSA) with a maximal frame rate of 1000 fps can be used to evaluate time-dependent flow details normally averaged out with lower frame rates. For new HSA image sequences, two different quantitative methods were utilized to extract high-temporal resolution velocity changes: X-Ray Particle Image Velocimetry (X-PIV) and optical flow (OF). A variety of flow conditions were examined in a range of patient-specific 3D-printed phantoms. Both pulsatile and constant flow settings were investigated. X-PIV was performed using radiopaque sub-millimeter microspheres, which were tracked throughout the image sequence to provide accurate, but limited sampling of the velocity field within the 3D-printed models. Also, an open source optical flow algorithm, OpenOpticalFlow, was used to perform velocity estimation based on the spatio-temporal intensity changes of iodinated contrast wavefronts. Periodic changes in velocity within each phantom ROI can be illustrated throughout the pulsatile cycle capture by the high-speed detector. In the constant flow sequences, changes in velocity across the phantom geometry can be seen. The ability to accurately measure detailed velocity distributions and velocity changes throughout various flow conditions at high temporal resolution enables further insight into the evaluation and treatment of neurovascular disease states.
Language	English
Publishing date	2021-02-15
Publishing country	United States
Document type	Journal Article
ISSN	0277-786X
ISSN	0277-786X
DOI	10.1117/12.2580888
Database	MEDical Literature Analysis and Retrieval System OnLINE

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Article: Leveraging Patient-Specific Simulated Angiograms to Characterize Cerebral Aneurysm Hemodynamics using Computational Fluid Dynamics.

Chivukula, V / White, R / Shields, A / Davies, J / Mokin, M / Bednarek, D R / Rudin, S / Ionita, C

Proceedings of SPIE--the International Society for Optical Engineering

2022 Volume 12036

Abstract: Cerebral aneurysms (CA) affect nearly 6% of the US population and its rupture is one of the major causes of hemorrhagic stroke. Neurointerventionalists performing endovascular therapy (ET) to treat CA rely on qualitative image sequences obtained under ... ...

Abstract	Cerebral aneurysms (CA) affect nearly 6% of the US population and its rupture is one of the major causes of hemorrhagic stroke. Neurointerventionalists performing endovascular therapy (ET) to treat CA rely on qualitative image sequences obtained under fluoroscopy guidance alone, and do not have access to crucial quantitative information regarding blood flow before, during and after treatment - partially contributing to a failure rate of up to 30%. Computational fluid dynamics (CFD) is a powerful tool that can provide a wealth of quantitative data; however, CFD has found limited utility in the clinic due to the challenges in obtaining hemodynamic boundary conditions for each patient. In this work, we present a novel CFD-based simulated angiogram approach (SAA) that resolves the blood flow physics and interaction between blood and injected contrast agent to extract quantitative hemodynamic parameters which can be used to design real-time parametric imaging analysis. The SAA enables correlating contrast agent transport to the underlying hemodynamic conditions via time-density curves (TDC) obtained at several points in the region of interest. The ability of the TDC and the SAA to provide critical hemodynamic parameters in and around CA anatomies, such as washout and local flow changes is explored and presented. This provides invaluable quantitative data to the clinician at the time of intervention, since it incorporates the physics of blood flow and correlates the contrast transport to hemodynamic parameters quantitatively - thereby enabling the clinician to take informed decisions that improve treatment outcomes.
Language	English
Publishing date	2022-04-04
Publishing country	United States
Document type	Journal Article
ISSN	0277-786X
ISSN	0277-786X
DOI	10.1117/12.2611473
Database	MEDical Literature Analysis and Retrieval System OnLINE

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