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Flow velocity measurement in haemodialysis access using 4D MRI

Treatment of renal failure while awaiting transplant requires vascular access, which comes with both complications and failure rates. In order to improve this, information about the AVF or AVG itself, as well as the haemodynamics is required. This data will then be used for computer modelling techni...

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Main Author: Downs, Jennifer
Other Authors: Kahn, Delawir
Format: Thesis
Language:English
Published: Department of Surgery 2017
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access_status_str Open Access
author Downs, Jennifer
author2 Kahn, Delawir
author_browse Downs, Jennifer
Kahn, Delawir
author_facet Kahn, Delawir
Downs, Jennifer
author_sort Downs, Jennifer
collection Thesis
description Treatment of renal failure while awaiting transplant requires vascular access, which comes with both complications and failure rates. In order to improve this, information about the AVF or AVG itself, as well as the haemodynamics is required. This data will then be used for computer modelling techniques and computational flow dynamics. Previously, the required imaging was provided by contrasted MRI, contraindicated in renal failure. Haemodynamic data was prvided by, amongst other things, duplex Doppler. New MRI software that provides imaging data as well as haemodynamic information without using contrast could be used to provide new high-quality data for modelling. Methods: This was a prospective pilot study. Six control cases (with no history of vascular illness or surgery of any kind to the right upper arm), as well as three grafts and five fistulae underwent phase contrast MR angiography of the right upper arm with a Siemens Magnetom Symphony 1.5T MRI Scanner. Images were then processed using Supertool in Matlab, and flow velocities at predetermined points on the brachial artery and cephalic vein, graft and fistula were calculated. Results: Velocities ranged from 5.8 cm/sec in a volunteer's brachial artery to 85.5 cm/sec in an arteriovenous fistula patient's brachial artery. Flow volumes in the cephalic vein or access varied from 6.9 ml/min. in a volunteer and up to 4398.1 ml/min. in an arteriovenous fistula. Graphical representations show marked haemodynamic changes throughout the imaged vessels. Conclusion: This technique provides good imaging and quantitative data about small vessel haemodynamics.
format Thesis
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institution University of Cape Town (South Africa)
language eng
last_indexed 2026-06-10T12:33:15.376Z
license_str Not specified — see source repository
provenance_str_mv Harvested via OAI-PMH from UCTD — University of Cape Town Open Access Repository
publishDate 2017
publishDateRange 2017
publishDateSort 2017
publisher Department of Surgery
publisherStr Department of Surgery
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source_str UCTD — University of Cape Town Open Access Repository
spelling oai:open.uct.ac.za:11427/22797 Flow velocity measurement in haemodialysis access using 4D MRI Downs, Jennifer Kahn, Delawir Franz, Thomas Surgery Treatment of renal failure while awaiting transplant requires vascular access, which comes with both complications and failure rates. In order to improve this, information about the AVF or AVG itself, as well as the haemodynamics is required. This data will then be used for computer modelling techniques and computational flow dynamics. Previously, the required imaging was provided by contrasted MRI, contraindicated in renal failure. Haemodynamic data was prvided by, amongst other things, duplex Doppler. New MRI software that provides imaging data as well as haemodynamic information without using contrast could be used to provide new high-quality data for modelling. Methods: This was a prospective pilot study. Six control cases (with no history of vascular illness or surgery of any kind to the right upper arm), as well as three grafts and five fistulae underwent phase contrast MR angiography of the right upper arm with a Siemens Magnetom Symphony 1.5T MRI Scanner. Images were then processed using Supertool in Matlab, and flow velocities at predetermined points on the brachial artery and cephalic vein, graft and fistula were calculated. Results: Velocities ranged from 5.8 cm/sec in a volunteer's brachial artery to 85.5 cm/sec in an arteriovenous fistula patient's brachial artery. Flow volumes in the cephalic vein or access varied from 6.9 ml/min. in a volunteer and up to 4398.1 ml/min. in an arteriovenous fistula. Graphical representations show marked haemodynamic changes throughout the imaged vessels. Conclusion: This technique provides good imaging and quantitative data about small vessel haemodynamics. 2017-01-18T13:11:31Z 2017-01-18T13:11:31Z 2016 Master Thesis Masters MMed http://hdl.handle.net/11427/22797 eng application/pdf Department of Surgery Faculty of Health Sciences University of Cape Town
spellingShingle Surgery
Downs, Jennifer
Flow velocity measurement in haemodialysis access using 4D MRI
thesis_degree_str Master's
title Flow velocity measurement in haemodialysis access using 4D MRI
title_full Flow velocity measurement in haemodialysis access using 4D MRI
title_fullStr Flow velocity measurement in haemodialysis access using 4D MRI
title_full_unstemmed Flow velocity measurement in haemodialysis access using 4D MRI
title_short Flow velocity measurement in haemodialysis access using 4D MRI
title_sort flow velocity measurement in haemodialysis access using 4d mri
topic Surgery
url http://hdl.handle.net/11427/22797
work_keys_str_mv AT downsjennifer flowvelocitymeasurementinhaemodialysisaccessusing4dmri