Comparative Study on the Changes of DTI and DTT of Optic Radiation and the Defect of Visual Field / 实用放射学杂志

ABSTRACT

Objective To study the relationship between the changes of diffusion tensor imaging(DTI)and diffusion tensor tractography(DTT)of optic radiation and the defect of visual field.Methods DTI and DTT were performed in 37 patients with invasion of the optic radiation by intracranial lesions and in 20 normal control group at 3.0T MR scanner,the visual fields of all cases were examined.The relativity between FA values,ADC values and mean sensitivity(MS)values,mean defect(MD)values of visual field and the relativity between the morphological change of optic radiation and the defect of visual field were analysed.Results In comparison with control group,FA values decreased and ADC values increased in subject group,there were statistically significant differences(P＜0.001)between them.In disordered group,FA values were positive correlation with MS values(r=0.718)and negative correlation with MD values(r=-0.694);ADC values were negative correlation with MS values(r=-0.625)and positive correlation with MD values(r=0.538).DTT showed that the ventral tracts of optic radiation were damaged which oppeared as the defect of ditto quadrant of bilateral field vision in 9 cases,the dorsal tracts and the lateral tracts of optic radiation were damaged which appeared as the defect of inferior quadrant of bilateral field vision in 7 cases,the optic radiations were damaged extensively that caused symmetric or asymmetric congruous hemianopia of bilateral field vision in 21 cases.Conclusion DTI and DTT of optic radiation are intimately correlated with the examined results of visual field,it will be a objective index to extimate the function and the morphological changes of optic radiation.