Abstract
To evaluate the effect of flip angle on flow rate measurements obtained with phase contrast MRI according to the flip angle degree in ascending aorta and velocity encoding (VENC) was (150 m/s). 1.5T MRI in patients 17 (female: 8, male: 9, mean age $57.9{\pm}15.4$) as a target by applying a non-breath holding techniques to flip angle VENC (150 cm/s) in each of the ascending aorta was measured by changing $20^{\circ}$, $30^{\circ}$ and $40^{\circ}$. Blood was obtained a peak velocity, average velocity, net forward volume, net forward volume/body surface area. Ascending aorta from average velocity (AV) measured the average value of the flip angle $20^{\circ}$ (9.87 cm/s), $30^{\circ}$ (9.6 cm/s) and $40^{\circ}$ (10.05 cm/s). Blood flow VENC in was blood flow change in flip angle change was high most blood flow measurement when the flip angle $30^{\circ}$ in VENC, crouching each blood flow is also proportional to the increases in the $20^{\circ}$ to $40^{\circ}$ and was increased, the deviation of the peak velocity and the average velocity is the smallest deviation from the flip angle $30^{\circ}$. Flip angle $20^{\circ}$, $30^{\circ}$ and $40^{\circ}$ in peak velocity, average velocity, net forward volume, net forward volume/body surface area was no statistically significant difference (p > .05). Blood flow velocity and blood flow is measured by applying to adjust the flip angle accurately calculate the blood flow is important information for diagnosis and treatment of cardiovascular diseases, and can help in the examination on the blood flow measurement.
자기공명영상에서 위상대조(phase contrast; PC) 기법으로 혈류 속도와 혈류량을 정량적으로 측정하기 위해 VENC(150 cm/s)에서 숙임각의 변화에 따른 혈류 속도와 혈류량을 측정하였다. 1.5T MRI로 지원자 17명(여: 8, 남: 9, 평균연령 $57.9{\pm}15.4$)을 대상으로 non-breath holding 기법을 적용하여 상행대동맥에서 VENC(150 cm/s)로 숙임각을 $20^{\circ}$, $30^{\circ}$, $40^{\circ}$ 변화하여 측정하였다. 혈류는 average velocity, peak velocity, net forward volume, net forward volume/body surface area를 획득하였다. 상행대동맥에서 AV(average velocity)의 평균값은 숙임각 $20^{\circ}$(9.87 cm/s), $30^{\circ}$(9.6 cm/s), $40^{\circ}$(10.05 cm/s)로 측정되었다. 숙임각을 $20^{\circ}$, $30^{\circ}$, $40^{\circ}$에서 peak velocity, average velocity, net forward volume, net forward volume/body surface area는 통계적인 유의한 차이가 없었다(p > .05). 혈류속도와 혈류량 측정은 매개변수를 조정하여 적용하면 심장혈관 질환의 진단 및 치료에 중요한 정보가 되는 혈류량을 정확히 계산하고, 혈류량 측정에 관한 연구에 도움을 줄 수 있다.