CAJ | 학술논문

目的：通过一次性大剂量照射大鼠视交叉建立视交叉损伤模型，研究锰离子增强MRI扫描（ MEMRI）在放射引起的视神经病变（ RION）中的作用。方法34只雌性Wistar大鼠，4只未进行照射作为对照组，30只大鼠按随机区组法随机分为照射后2个月组、照射后4个月组、照射后6个月组，分别于相应时间点行MEMRI扫描，扫描后处死大鼠并进行脑组织和视神经HE染色及快蓝（ LFB）染色及电镜等病理学分析。结果对照组、照射后2个组、照射后4个月组、照射后6个月组发生RION的比例分别为0/4、1/5、2/4、11/11，差异有统计学意义（χ2＝15?443，P＜0?05）；LFB染色相对光密度值与视交叉照射后时间呈负相关（R＝-0?643，P＜0?05）；各组每光镜视野下星形细胞数分别为194±65、234±19、124±11及345±98，相关性分析显示细胞数与照射后时间呈正相关（R＝0?590，P＜0?05）。 MEMRI图像显示，照射后2个月组的5只大鼠中，1只出现视神经传导功能丧失，但较其余4只未见明显病理学改变。结论应用MEMRI对视觉通路功能完整性进行随访和半定量评估，可在病理改变之前直观地提示视神经功能是否发生传导障碍。
목적：통과일차성대제량조사대서시교차건립시교차손상모형，연구맹리자증강MRI소묘（ MEMRI）재방사인기적시신경병변（ RION）중적작용。방법34지자성Wistar대서，4지미진행조사작위대조조，30지대서안수궤구조법수궤분위조사후2개월조、조사후4개월조、조사후6개월조，분별우상응시간점행MEMRI소묘，소묘후처사대서병진행뇌조직화시신경HE염색급쾌람（ LFB）염색급전경등병이학분석。결과대조조、조사후2개조、조사후4개월조、조사후6개월조발생RION적비례분별위0/4、1/5、2/4、11/11，차이유통계학의의（χ2＝15?443，P＜0?05）；LFB염색상대광밀도치여시교차조사후시간정부상관（R＝-0?643，P＜0?05）；각조매광경시야하성형세포수분별위194±65、234±19、124±11급345±98，상관성분석현시세포수여조사후시간정정상관（R＝0?590，P＜0?05）。 MEMRI도상현시，조사후2개월조적5지대서중，1지출현시신경전도공능상실，단교기여4지미견명현병이학개변。결론응용MEMRI대시각통로공능완정성진행수방화반정량평고，가재병리개변지전직관지제시시신경공능시부발생전도장애。
Objective To establish a rat model of radiation-induced optic neuropathy ( RION) by delivering a single radiation dose to the optic chiasm. The aim of our study was to analysis the feasibility and effectiveness of manganese-enhanced magnetic resonance imaging ( MEMRI) in RION. Methods 34 Wistar rats were randomized to the control group(4 rats), the 2-month group(5 rats),the 4-month group(4 rats) and the 6-month group(11 rats) according to the different feeding period after irradiation. MEMRI scan were performed when the respective feeding periods of all groups expired. The rats were then killed for histological studies with hematoxylin and eosin stain, Luxol Fast Blue stain, and electron microscopy analysis. Results The ratio of RION in the four groups were 0/3, 1/5, 2/4 and 11/11, respectively (χ2 =15?443, P<0?05). There was an inverse correlation between the relative optical density value in the LFB stain and the interval between irradiation and pathological examination(R= -0?643,P<0?05). The number of glial cells in the HE stain in the four groups were 194 ± 65, 234 ± 19, 124 ± 11 and 345 ± 98, respectively(R=0?590,P<0?05). When compared MEMRI scan with the corresponding histological examination, we found that there was loss of signals of optic nerve on MEMRI imaging in one of 5 rats in the 2-month group, while no significant histological difference was found between this rat and the others. Conclusions RION can be non-invasively detected and semi-quantitative analysed by MEMRI scan. Moreover, RION can be early diagnosed by MEMRI scan which is capable to show physiological change in advance of pathological change.