고속스핀에코 기법을 이용한 MRI 검사 시 영상 변수가 전자파 흡수율과 온도 증가에 미치는 영향 평가 : 재위상화 RF의 FA과 ETL 증가에 따른 영향 = The Effect of Imaging Parameters on SAR and Temperature Rise during MRI Examinations Using the Fast Spin Echo Technique: The Effects of Increasing the FA of the Refocusing RF and ETL

다국어 초록 (Multilingual Abstract)

The purpose of this study was to evaluate the effect of imaging parameters on SAR and temperature rise in MRIs using the fast spin echo (FSE) technique. To evaluate the effect of imaging parameters, a human equivalent tissue phantom was created and MRI was performed with increasing refocusing FA and ETL under the same conditions. The head SAR value calculated from the device was used, and the temperature rise of the phantom was calculated using the proton resonance frequency. When the FA was increased from 60° to 180°, the SAR increased by approximately 8 times and the temperature rise of the phantom increased by approximately 2.8 times (0.21°-0.599°). In a multiple regression analysis, FA had a high correlation with the β of 0.935 and 0.741 in the relationship between SAR and temperature rise. When the ETL was increased from 15 to 30, the SAR increased by approximately 2 times. However, the temperature rise of the phantom decreased by 39.2% (0.53°-0.303°). In the multiple regression analysis results, ETL had a positive correlation with the β of 0.741 in the relation of SAR but a β of −0.482 for temperature rise, exhibiting a negative correlation. This may be attributable to the decrease in the exposure time to electromagnetic waves; the scan time was shortened by approximately 43% as the ETL was increased from 15 to 30. Ultimately, MRI using the FSE technique is expected to improve patient safety by minimizing refocusing FA and maximizing ETL within the reference SAR range to minimize temperature rise due to electromagnetic waves