Experimental investigation of the accuracy for absolute quantification of brain creatine concentration using long time echo point resolved spectroscopy sequence with an external standard and linear combination of model spectra / 中华放射学杂志

ABSTRACT

Objective To investigate the accuracy for absolute quantification of brain creatine (Cr) concentration using long time echo (TE) point resolved spectroscopy (PRESS) sequence performed with an external standard and postprocessed with the linear combination of model spectra (LCModel).Methods Ten swine (3.1±0.6 kg) and an external standard phantom containing detectable compounds of known concentration were investigated in this study by using 1.5 T GE Signa scanner and a standard head coil. The single-voxel proton magnetic resonance spectroscopy (1H-MRS) data were acquired from the two ROIs (2 cm×2 cm×2 cm) placed in swine brain and external standard solution using PRESS sequence with TE 135 ms,TR 1500 ms,and 128 scan averages.The in vivo quantification of Cr was accomplished by LCModel.After 1H-MRS examination,each animal was sacrificed immediately.In vitro Cr concentration was analyzed by high performance liquid chromatography (HPLC).Results In the 1H-MRS group,the Cr concentration was (9.37±0.14)mmol/kg.In the HPLC group,the Cr concentration was (8.91±0.13)mmol/kg.Good agreement was obtained between these two methods (t=9.038,P=0.491).Conclusion The long echo time PRESS sequence performed with an external standard and processed with LCModel iS proven to be an accurate technique to detect the in vivo brain Cr concentration.