PROBLEM TO BE SOLVED: To suppress the effects of magnetization transfer to increase the accuracy of calculating brain parenchyma T1, T2 and reduce the variation of blood flow T1 value due to the effects of the blood flow when acquiring the subject parameter distribution by MRI.SOLUTION: A high-frequency magnetic field pulse in a narrow frequency band is used as an excitation pulse in an imaging for parameter estimation to thereby suppress the effects of magnetization transfer. The high-frequency magnetization field pulse takes a shape similar to that of a Gaussian function in the excitation profile when the frequency band is made narrower. The rising part of the pulse is located in the field of view with the head as an object to be imaged.SELECTED DRAWING: Figure 4COPYRIGHT: (C)2019,JPO&INPIT【課題】ＭＲＩにより被検体パラメータ分布を取得する際に、磁化移動効果を抑制して脳実質のＴ１、Ｔ２の算出精度を向上させ、かつ、血流の影響による血液のＴ１値の変動を低減する。【解決手段】パラメータ推定のための撮影において、励起パルスとして周波数帯域の狭い高周波磁場パルスを用い、磁化移動効果を抑制する。高周波磁場パルスは、周波数帯域を狭くすると励起プロファイルはガウス関数に近い形状になる。その立ち上がり部分を、頭部を撮影対象とした視野に配置する。【選択図】図４
