Simple compensation method for improved half-pulse excitation profile with rephasing gradient

Kód výsledku v IS VaVaI

<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F68081731%3A_____%2F20%3A00535931" target="_blank" >RIV/68081731:_____/20:00535931 - isvavai.cz</a>

Nalezeny alternativní kódy

RIV/00216224:14740/20:00116481

Výsledek na webu

<a href="https://onlinelibrary.wiley.com/doi/abs/10.1002/mrm.28233" target="_blank" >https://onlinelibrary.wiley.com/doi/abs/10.1002/mrm.28233</a>

DOI - Digital Object Identifier

<a href="http://dx.doi.org/10.1002/mrm.28233" target="_blank" >10.1002/mrm.28233</a>

Jazyk výsledku

angličtina

Název v původním jazyce

Simple compensation method for improved half-pulse excitation profile with rephasing gradient

Popis výsledku v původním jazyce

Purpose: To improve the slice profile quality obtained by RF half-pulse excitation for 2D-UTE applications. Methods: The overall first-order and zero-order phase errors along the slice-selection direction were obtained with the help of an optimization task to minimize the out-of-slice signal contamination from the calibration 1-dimenisonal (1D) profile data. The time-phase-error evolution was approximated from the k-space readout data, which were acquired primarily for correction of the readout trajectories during data regridding to the rectilinear grids. The correction of the slice profile was achieved by rephasing gradient pulses applied immediately after the end of excitation. The total prescan calibration typically took less than 2 minutes. Results: The improved image quality using the proposed calibration method was demonstrated both on phantoms and on ankle images obtained from healthy volunteers. It was demonstrated that calibration can be performed either as a separate water phantom measurement or directly as a prescan procedure. Conclusion: The slice-profile distortion from the half-pulse excitation could substantially affect the overall fidelity of 2D-UTE images. The presented experiments proved that the image quality could be substantially increased by application of the proposed slice-correction method.

Název v anglickém jazyce

Simple compensation method for improved half-pulse excitation profile with rephasing gradient

Popis výsledku anglicky

Purpose: To improve the slice profile quality obtained by RF half-pulse excitation for 2D-UTE applications. Methods: The overall first-order and zero-order phase errors along the slice-selection direction were obtained with the help of an optimization task to minimize the out-of-slice signal contamination from the calibration 1-dimenisonal (1D) profile data. The time-phase-error evolution was approximated from the k-space readout data, which were acquired primarily for correction of the readout trajectories during data regridding to the rectilinear grids. The correction of the slice profile was achieved by rephasing gradient pulses applied immediately after the end of excitation. The total prescan calibration typically took less than 2 minutes. Results: The improved image quality using the proposed calibration method was demonstrated both on phantoms and on ankle images obtained from healthy volunteers. It was demonstrated that calibration can be performed either as a separate water phantom measurement or directly as a prescan procedure. Conclusion: The slice-profile distortion from the half-pulse excitation could substantially affect the overall fidelity of 2D-UTE images. The presented experiments proved that the image quality could be substantially increased by application of the proposed slice-correction method.

Druh

J_imp - Článek v periodiku v databázi Web of Science

CEP obor

—

OECD FORD obor

20602 - Medical laboratory technology (including laboratory samples analysis; diagnostic technologies) (Biomaterials to be 2.9 [physical characteristics of living material as related to medical implants, devices, sensors])

Projekt

Výsledek vznikl pri realizaci vícero projektů. Více informací v záložce Projekty.

Návaznosti

I - Institucionalni podpora na dlouhodoby koncepcni rozvoj vyzkumne organizace

Rok uplatnění

2020

Kód důvěrnosti údajů

S - Úplné a pravdivé údaje o projektu nepodléhají ochraně podle zvláštních právních předpisů

Název periodika

Magnetic Resonance in Medicine

ISSN

0740-3194

e-ISSN

—

Svazek periodika

84

Číslo periodika v rámci svazku

4

Stát vydavatele periodika

US - Spojené státy americké

Počet stran výsledku

10

Strana od-do

1796-1805

Kód UT WoS článku

000561641400001

EID výsledku v databázi Scopus

2-s2.0-85080864080