Experimentelle Magnetresonanzangiographie unter Verwendung von kontrastangehobenen und flußrichtungssensitiven Meßtechniken

Purpose: 1.Evaluation and further development of a new flow sensitive MR protocol in a pig model. 2.To prove the value of blood pool contrast agents in MR coronary angiography using an established ultrafast two dimensional gradient echo sequence. Material and methods: After verification and modification of the MR sequence sensitive to flow direction in a plastic tube model the sequence was performed in 8 pigs using a 1.5 Tesla MRI-Scanner (Philips Gyroscan ACS NT). The MR angiography protocol was applied in two-dimensional spin-echo- and echoplnar (EPI) technique with variable located excitation- and refocussing HF-pulses in the direction of slice-selection to obtain selective imaging of arterious and venous structures. In systematic studies several parameters were changed as the repetition time, the echo time, the slice thickness, flip angle and the sizes of excitating and refocussing HF-pulses. At another day the same animals underwent a further study: an ultrafast two-dimensional T1-weighted gradient echo protocol for bright-blood imaging of coronary vessels was performed with application of a gadolinium-based blood-pool contrast agent ( Gadomer 17, Schering AG) in dose of 0.2 mmol per kilogram of body weight. During the studies the measurement protocol was improved. Results and discussion: 1. Using local deviated HF-pulses in spin-echo sequences selective imaging of arteries and veins is possible without contrast agent only due to flow direction. The protocol is more sufficient in the imaging of veins, imaging of arteries is not satisfying due to low signal- to noise ratios and severe ghosting artifacts. 2. In coronary MRA higher signal levels in proximal coronary anatomy can be obtained by using blood pool contrast agents, a further depiction of the distal and small coronary vessels does not occur.

Grantor dc:publisher

Publikationsserver der RWTH Aachen University

Year dc:date

2000

Author dc:creator

• Stracke, Christian Paul

Contributors dc:contributor

• Adam, Gerhard

• info:eu-repo/classification/ddc/610
• Medizin

Statement dc:rights

• info:eu-repo/semantics/openAccess

Language dc:language

ger

Identifier

https://publications.rwth-aachen.de/search?p=id:%22RWTH-CONV-121208%22

OAI identifier oai:identifier

oai:publications.rwth-aachen.de:59421