Pregled pulznih zaporedij pri magnetno resonančni angiografiji : diplomsko delo

Jerebic, Gregor (author), Podobnik, Janez (mentor), Robida, Tina (co-mentor), Starc, Tina (reviewer)

Uvod: Magnetno resonančna angiografija (MRA) predstavlja kompleksnejši način slikanja vaskularnega sistema napram osnovnim magnetno resonančnim pulznim zaporedjem. Osnovne MRA tehnike slikanja vaskularnega sistema delimo na slikanje temne in svetle krvi. Slikanje svetle krvi predstavljata time of flight (TOF) in phase contrast (PC) tehniki slikanja. Poznamo še MRA preiskavo z uporabo kontrastnega sredstva, kjer se bolniku najpogosteje aplicira gadolinijevo kontrastno sredstvo. Namen: Namen diplomskega dela je na podlagi sistematičnega pregleda literature ugotoviti, katere so prednosti in slabosti posameznih pulznih zaporedij pri magnetno resonančni angiografiji. Metode dela: V diplomskem delu smo uporabili deskriptivno metodo s sistematičnim pregledom literature. Uporabljeni podatki so bili pridobljeni na podlagi preučevanja znanstvenih in strokovnih člankov ter raziskav na področju magnetno resonančnih angiografskih preiskav. Na podlagi pregledane literature smo nato primerjali različna pulzna zaporedja uporabljena v le-teh preiskavah. Literaturo smo pridobili iz različnih podatkovnih baz, tako slovenskih, kot tudi tujih. Iskali smo jo v obdobju med oktobrom 2019 in majem 2020. Rezultati: V rezultatih smo predstavili bistvene ugotovitve znanstvenih in strokovnih člankov ter raziskav vključenih v diplomsko delo. Najboljše rezultate je v večini primerov dosegala MRA tehnika slikanja z uporabo kontrastnega sredstva, vendar so ji bile preostale tehnike v veliki večini primerov enakovredne. Na razultate vseh posameznih raziskav je najbolj vplivala izbira anatomskega področja, katerega se je preiskovalo z uporabo različnih tehnik slikanja vaskularnega sistema. Razprava in zaključek: Ugotovili smo, da ima vsako izmed primerjanih pulznih zaporedij svoje pozitivne in negativne lastnosti. Le-te izvirajo iz principa delovanja posameznega pulznega zaporedja. Zaradi tega se moramo pred vsako preiskavo znova odločati, katero pulzno zaporedje bomo uporabili, da bomo lahko anatomske strukture ali bolezenske spremembe najboljše prikazali na končni sliki. TOF-MRA tehnika slikanja je primernejša za slikanje hitro pretekajoče se krvi, kar pomeni, da se najboljše odreže pri slikanju arterijskega dela vaskularnega sistema. PC-MRA se najpogosteje uporablja pri slikanju venskega sistema, saj le-tam kri po žilah teče z nižjo hitrostjo, kot v arterijah, sama tehnika slikanja nam pa omogoča, da prednastavimo hitrost pretoka krvi, pri kateri bi radi zajemali podatke oziroma pridobivali na sliki povišan signal. MRA z uporabo kontrastnega sredstva predstavlja invazivno tehniko slikanja vaskularnega sistema, ker bolniku pred ali med preiskavo apliciramo gadolinijevo kontrastno sredstvo. Le-to kontrastno sredstvo se na slikah prikaže s hiperintenzivnim signalom in nam tako najboljše izmed vseh treh tehnik prikaže manjše žilne strukture.

• Language: Slovenian
• Keywords: diplomska dela, radiološka tehnologija, magnetno resonančna angiografija, time of flight MRA, phase contrast MRA, MRA z uporabo kontrastnega sredstva
• Work type: Bachelor thesis/paper
• Typology: 2.11 - Undergraduate Thesis
• Organization: ZF - Faculty of Health Sciences
• Place of publishing: Ljubljana
• Publisher: [G. Jerebic]
• Year: 2020
• Number of pages: 35 str.
• PID: 20.500.12556/RUL-118677
• UDC: 616-07
• COBISS.SI-ID: 26856451
• Publication date in RUL: 30.08.2020

Secondary language

• Language: English
• Title: Overview of pulse sequences in magnetic resonance angiography : diploma work

Abstract

Introduction: Magnetic resonance angiography is a more complex way of imaging the vascular system compared to basic MRI pulse sequences. We divide the basic MRA imaging techniques into two groups named "black blood" MRA and "bright blood" MRA. Bright blood imaging includes the time of flight (TOF) and phase contrast (PC) imaging techniques. There is also a third imaging technique called contrast enhanced MRA which uses a contrast agent (mostly gadolinium) that is applied to the patients blood flow. Purpose: The purpose of our diploma work is to find all of the positive and negative qualities of each individual pulse sequence compared in this diploma work on the base of our systematic literature review. Methods: We used the descriptive method in combination with a systematic literature review. Information used in our diploma work was gathered by studying different scientific articles and researches on MRA imaging techniques. On the base of the studied literature we compared different MRI pulse sequences researched in these studies between each other. The literature we used in this diploma work was found in different data bases on the world wide web, the data bases were slovenian and mostly foreign. We collected all of the data in the time frame from october 2019 until may 2020. Results: In the results we presented the most essential findings in the scientific articles and researches used in our work. In most cases the best results were achieved by the CE-MRA imaging technique, although the other two pulse sequences were not far behind or were even just as good as the CE-MRA pulse sequence itself. The biggest factor that influenced the final results of each of the articles was the anatomical region of interest that was imaged during the researches. Discussion and conclusion: We figured out that every pulse sequence researched in our work has some positive and some negative qualities. These qualities are defined by the work principles of every individual pulse sequence. Because of that, we need to decide which one of them we will use for each examination that we will be performing so that we always get the best image of an anatomical structure or a pathology. TOF-MRA is a technique better suited for imaging high velocity blood flows, which means it is better for imaging the arterial part of the vascular system. PC-MRA is mostly used for imaging the venous system which has a lower velocity blood flow compared to the arterial one. This is based on the PC-MRAs capability to set a predetermined velocity value at which imaging data will be acquired. CE-MRA is an invasive imaging technique where a contrast agent is applied to the patients blood flow. This contrast agent is on the final images shown as increased signal and is therefore very helpful for displaying smaller vascular structures.

• Keywords: diploma theses, radiologic technology, magnetic resonance angiography, time of flight MRA, phase contrast MRA, contrast enhanced MRA