Medical Imaging and Radiotherapy Journal (MIRTJ) 39 (Suppl. 1) 31 Medical Imaging and Radiotherapy Journal (MIRTJ) 39 (Suppl. 1) T1 IN T2 MAPIRANJE PRI MAGNETNORESONANČNEM SLIKANJU SRCA T1 AND T2 MAPPING IN MAGNETIC RESONANCE IMAGING OF THE HEART Laura Šubej 1, Andrej Breznik 1, Boris Turk 1, Nejc Mekiš 2 1 Splošna Bolnišnica Celje, Radiološki oddelek, Oblakova ulica 5, 3000 Celje, 1000 Slovenija / General Hospital Celje, Department of Radiology, Oblakova ulica 5, 3000 Celje, 1000 Slovenia 2 Univerza v Ljubljani, Zdravstvena fakulteta, Oddelek za radiološko tehnologijo, Zdravstvena pot 5, 1000 Ljubljana, Slovenija / University of Ljubljana, Faculty of health sciences, Medical Imaging and Radiotherapy Department, Zdravstvena pot 5, 1000 Ljubljana, Slovenia Korespondenca / Corresponding author: laura.subej@sb-celje.si Prejeto/Recived: 12. 1. 2022 Sprejeto/Accepted: 2. 3. 2022 IZVLEČEK Uvod: Magnetnoresonančno slikanje srca predstavlja največjo prednost za tridimenzionalen prikaz struktur z odlično prostorsko in visokokontrastno ločljivostjo. Tako se omogoča merjenje srčne funkcije in ocena morfoloških struktur. Napredek tehnologije ponuja možnost slikanja s T1 in T2 mapiranjem. Namen: Ugotoviti nativne vrednosti T1 in T2 mapiranja pri zdravih preiskovancih ter ugotoviti vpliv preiskovalnega polja na vrednosti T1 in T2 relaksacijskega časa pri izvajanju T1 in T2 mapiranja. Metode: V raziskavo je bilo vključenih 30 zdravih prostovoljcev. Raziskava je potekala na MR aparatu znamke Siemens Magnetom Aera 1.5 T. Vsakemu prostovoljcu smo opravili nativno T1 in T2 mapiranje srčne mišice. Izvedli smo korekcijo velikosti FOV, tako da smo velikost povečevali za 10 mm, in sicer od 360 mm do 390 mm. V drugem delu raziskave pa smo v računalniški program vrisovali interesna področja v interventrikularni septum ter primerjali meritve. Rezultati: Primerjava velikosti slikovnega polja je pokazala, da obstajajo minimalne statistične razlike v vrednosti T1 relaksacijskih časov. Vse izmerjene vrednosti so v okvirih referenčnih vrednosti. Primerjava med velikostjo slikovnega polja pri T2 mapiranju je pokazala, da ne obstajajo statistično značilne razlike v T2 relaksacijskih časih. Vse izmerjene in izračunane vrednosti so v okvirnih referenčnih vrednostih T2 relaksacijskih časov. Med raziskavo smo ugotovili, da obstajajo razlike med spoloma tako pri T1 kot tudi T2 mapiranju. Razprava in zaključek: Ugotovili smo, da so povprečne nativne vrednosti T1 in T2 mapiranja primerljive z rezultati drugih raziskav in z referenčnimi vrednostmi zdravega miokarda. V drugem delu raziskave smo ugotavljali, ali velikost slikovnega polja vpliva na izmerjene vrednosti T1 in T2 mapiranja pri MR slikanju srca. Ugotovili smo, da obstajajo posamezne minimalne razlike med vrednostmi T1 in T2 relaksacijskih časov, vendar še vedno v okviru normalnih vrednosti. Ključne besede: MR slikanje srca, T1 mapiranje, T2 mapiranje ABSTRACT Introduction: Magnetic resonance imaging of the heart is used worldwide today in the fi eld related to cardiovascular disease. The biggest advantage of magnetic resonance imaging of the heart is the three-dimensional display of structures with excellent spatial and high contrast resolution. It enables the measurement of cardiac function and the assessment of morphological structures. Advances in technology have made imaging possible with T1 and T2 mapping. Purpose: To determine the native values of T1 and T2 mapping in healthy subjects and to determine the infl uence of the test fi eld on the values of T1 and T2 relaxation time when performing T1 and T2 mapping. Methods: 30 healthy volunteers were included in the study. The study was performed on a Siemens Magnetom Aera 1.5 T MR. None of the volunteers had a known history of cardiovascular disease or risk factors. For each volunteer, we performed native T1 and T2 mapping of the heart muscle at diff erent image fi eld sizes. We performed a size correction of the FOV by increasing the size by 10 mm, from 360 mm to 390 mm. In the second part of the research, we plotted areas of interest in the interventricular septum in a computer program and recorded measurements. Results: A comparison between image fi eld sizes in T1 mapping showed that there were minimal statistical diff erences in the values of T1 relaxation times. All measured and calculated values were within the reference values of T1 relaxation times. A comparison between the image fi eld sizes in T2 mapping showed that there were no statistically signifi cant diff erences in the values of T2 relaxation times. All measured and calculated values were in the approximate reference values T2 of relaxation times. The research has found gender diff erences in both T1 and T2 mapping. Discussion and conclusion: We found that the average native values of T1 and T2 mapping are comparable with the results of other studies and that they can be compared with the native reference values of a healthy myocardium. In the second part of the study, we investigated whether the size of the image fi eld aff ects the measured values of T1 and T2 32 Medical Imaging and Radiotherapy Journal (MIRTJ) 39 (Suppl. 1) Medical Imaging and Radiotherapy Journal (MIRTJ) 39 (Suppl. 1) mapping in MR imaging of the heart. We found that there are individual minimal diff erences between the calculated values of T1 and T2 relaxation times, but the measured values are still within normal values. Keywords: MR imaging of heart, T1 mapping, T2 mapping LITERATURA / REFERENCES Amano, Y., Kitamura, M., Takano, H., Yanagisawa, F., Tachi, M., Suzuki, Y., Kumita, S., & Takayama, M. (2018). Cardiac MR Imaging of Hypertrophic Cardiomyopathy: Techniques, Findings, and Clinical Relevance. 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