CAJ | 학술논문

目的探讨新型对比剂Gadofluorine M(Gf)在MRI早期诊断大鼠放射性脑损伤中的应用.方法 66只大鼠随机分为25、35、45、55和65 Gy组,各12只,对照组6只,X射线照射构建大鼠放射性脑损伤模型,照射后1～8周行MRI平扫及Gf增强扫描,每周1次.另取12只大鼠分为55及65 Gy组,每组6只,照后3～8周行钆喷酸葡胺(Gd-DTPA)增强及Gf增强扫描,每周1次.比较损伤显像时间、MRI参数和病理学改变评价放射损伤.结果 25及35 Gy放射组在观察2个月内MRI未发现异常信号改变,45、55及65 Gy组在放射后4～6周内,T1 WI Gf增强扫描中逐渐出现强化改变,信号强度与对照组、25和35 Gy组差异有统计学意义(F=2.15,P＜0.05),出现时间与剂量成反比(r=-0.62,P＜0.05).Gd-DTPA增强及Gf增强扫描对比结果显示,Gd-DTPA增强扫描未发现明显改变时Gf增强可见损伤改变,Gf增强信号强度较平扫及Gd-DTPA增强明显强化(F=2.74,P＜0.01).病理检查示65 Gy组病理学检查发现部分区域出现毛玻璃样变性,其余各组均未发现明显异常.结论 Gadofluorine M增强改变出现在病理改变之前,可用以早期发现放射性脑损伤,较常规扫描序列及Gd-DTPA增强扫描具有明显优势.
목적 탐토신형대비제Gadofluorine M(Gf)재MRI조기진단대서방사성뇌손상중적응용.방법 66지대서수궤분위25、35、45、55화65 Gy조,각12지,대조조6지,X사선조사구건대서방사성뇌손상모형,조사후1～8주행MRI평소급Gf증강소묘,매주1차.령취12지대서분위55급65 Gy조,매조6지,조후3～8주행구분산포알(Gd-DTPA)증강급Gf증강소묘,매주1차.비교손상현상시간、MRI삼수화병이학개변평개방사손상.결과 25급35 Gy방사조재관찰2개월내MRI미발현이상신호개변,45、55급65 Gy조재방사후4～6주내,T1 WI Gf증강소묘중축점출현강화개변,신호강도여대조조、25화35 Gy조차이유통계학의의(F=2.15,P＜0.05),출현시간여제량성반비(r=-0.62,P＜0.05).Gd-DTPA증강급Gf증강소묘대비결과현시,Gd-DTPA증강소묘미발현명현개변시Gf증강가견손상개변,Gf증강신호강도교평소급Gd-DTPA증강명현강화(F=2.74,P＜0.01).병리검사시65 Gy조병이학검사발현부분구역출현모파리양변성,기여각조균미발현명현이상.결론 Gadofluorine M증강개변출현재병리개변지전,가용이조기발현방사성뇌손상,교상규소묘서렬급Gd-DTPA증강소묘구유명현우세.
Objective To explore the value of Gadofluorine M,a novel M RI enhancement agent,in the diagnosis the early radiation brain injury.Methods Seventy-two Wistar rats were randomly divided into 5 equal groups.To establish the radiation injury model,the rat's posterior brain was irradiated with 0(blank controls),25,35,45,55,and 65 Gy,respectively.After irradiation MR plain scanning and Gadofluorine M enhancement scanning (after the T1WI and T2WI scanning Gf at the dosage of 0.1 mmol/kg was injected intravenously and scanning was performed again 12 h later) were performed once a week for 8 weeks.Another 12 rats were randomly divided into 2 equal groups to exposure to 55 and 65Gy,respectively,and MR scanning was performed once a week for 8 weeks since the third week after MR.After T1WI and T2WI scanning Gd-DTPA was injected intravenously,MR was conducted again 30 min later,and Gf was injected intravenously (Gd-DTPAenhancement and Gf enhancement contrast).The MR image and the pixel count were compared.Since the third week 2 rats from the Gf enhancement scanning group and 1 rat from the Gd-DTPA enhancement and Gf enhancement contrast were killed after MR with their brains taken out to undergo pathological examination.Results No abnormal signal changes were found in MRI in 25 and 35 Gy groups within 2 months after irradiation.A high signal in the Gf enhancement T1 WI image was found in 45,55,and 65 Gy groups within the period of 4-6 weeks after radiation.The signal intensity was significantly higher than that of the control,25,and 35 Gy groups(F =2.15,P <0.05).The emerge time of this signal was negatively correlated with the dose of radiation(r =-0.62,P < 0.05).When there was no obvious change was found by Gd-DTPA enhancement,a high signal representing change of injury could be found in Gf enhancement in the same rat.The signal intensity was significantly enhanced in Gf enhancement compared to the Gd-DTPA enhancement (F = 2.74,P <0.01).Histopathology examination of the 65 Gy group showed frosted degeneration in part of the region,however,no obvious necrotic damage was found in other groups.Conclusions The Gf enhancement change appears before histopathological changes,it helps discover early radiation injury in brain.Compared to the regular MRI and Gd-DTPA enhancement,Gadofluorine M enhancement has obvious advantage and is worth further research and application.