Comparison of Pulse Sequences of Magnetic Resonance Imaging for Optimization of Timing and Image Quality

TLDR: FSE and FLAIR produced optimal image quality for many tissues because of their reduced acquisition time, which could make them perfect option for patients who cannot tolerate longer imaging time.

Abstract: Introduction: The present study aimed to three frequently used pulse sequences of magnetic resonance imaging (MRI) to assess the image quality of theses pulse sequences at short acquisition time. Material and Methods: For the purpose of study two tissue equivalent gels were prepared. One gel was made from Polysaccharide and Agarose, whereas second gel was obtained from Ferrous Benzoic Xylenol Orange (FBX) which is tissue equivalent material. 6MV photons were used to irradiate FBX gel from linear accelerator with 25 Gray dose. Imaging parameters are performed in repetition time (TR) for experimental variations. The quantitative analysis included contrast-to-noise ratio (CNR) and signal to noise ratio (SNR). Results: As evidenced by obtained results at 1.5 Tesla, Fast Spin Echo (FSE) and Fast Fluid Attenuated Inversion Recovery (FLAIR) were most comparable in SNR although, acquisition time of FSE is 62%, 9 %, and 15% less than FLAIR at different values of 4000ms, 4200ms and 4600ms of TR. CNR of Conventional Spin Echo (CSE) was 143% and 93% better than FSE and FLAIR respectively. The time difference between CSE and FSE was 6 min and 34 sec while this difference was 6 min and 43 sec between CSE and FLAIR. Conclusion: FSE and FLAIR produced optimal image quality for many tissues. Their reduced acquisition time could make them perfect option for patients who cannot tolerate longer imaging time. Nonetheless long acquisition time cannot undervalue importance of CSE since it has yielded significantly higher contrast and SNR in T2-weighted images among other pulse sequences of MRI.