Introduction: Magnetic resonance (MR) imaging is one of the most dynamic and safe imaging techniques available in the clinic today. However the acquisition of MR images tends to be slow, which limits the number of patients treated and thus the potential indications for its use, while also increasing the cost of its use. Compressed sensing (CS) is a method to speed up MR data acquisition by acquiring less data with reduced k-space sampling. In turn this can reduce the time intensity of the MR examination. Purpose: The purpose is to present the sequence acceleration technique in magnetic resonance imaging of the brain. The main aim of this research is to measure which of the acceleration factors of a 3-dimensional T1-turbo field echo sequence (3D T1 TFE) is optimal or the best for MR imaging of the brain and incorporate this acceleration factor into everyday use in MR imaging of the brain. The aim of the work is also to determine whether the quality and time of the image capture are adequate in relation to the imaging acceleration factor. Methods: We conducted the research in two parts. In the first part of the research we conducted a prospective study using an experimental method, .where 30 healthy volunteers were included for imaging. In the second part, after the collected image data we performed SNR (signal-to-noise ratio) and CNR (contrast-to-noise ratio) measurements in different brain regions. All acquired MR images were then evaluated by two specialist radiologists. The two doctors assessed the following image characteristics: overall image quality, image sharpness, SNR and contrast resolution. Results: The research showed that there were no statistically significant differences in SNR and CNR measurements in the white matter and lateral ventricles when comparing the reference and CS 3 sequence (p > 0.05). Statistically significant differences (p < 0.05) were found between the reference and all accelerated pulse sequences (SENSE 3, CS3, CS 3.5, CS 4 and CS 4.5) in SNR and CNR measurements in the gray matter. We observed no statistically significant differences between the mean CNR values of the lateral ventricle in the accelerated pulse sequences SENSE 3 (p=0.992), CS 3 (p = 0.643) and C3 3.5 (p = 0.171). The results of the image assessment showed that there were no statistically significant differences in the image quality scores for all four image characteristics assessed between the reference and CS 3 pulse sequences. Discussion and conclusion: With research, we found that the optimal CS acceleration factor for the 3D T1 TFE sequence is CS 3. This saves 47 % of the time per pulse sequence with practically the same image quality compared to the reference. By using accelerated sequences, we can enable patients to have a shorter examination time, while simultaneously increasing the number of examinations performed and their accessibility.
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