ABSTRACT
Objective To evaluate the value of susceptibility-weighted imaging (SWI)sequence in the diagnosis of metastatic en-cephaloma pre and after radiotherapy by comparing the appearance of the SWI and contrast-enhanced T1-weighted imaging(T1 WI). Methods Thirty-eight lung cancer patients with brain metastases underwent SWI and contrast-enhanced T1-weighted imaging re-spectively before and 2-3 months after radiotherapy.Evaluated the two methods by score(the score ranged from 0-3,0 represen-ted no showing,1 represented not showing clearly,2 represented could judging,3 represented showing obviously).Results Before radiotherapy,SWI detected 1 61 lesions of metastases and could obviously show tumor vascular in brain metastases (mean score 2.73±0.05).Contrast-enhanced T1 WI detected 1 61 lesions(mean score 1.93±0.04 ).SWI showed significantly higher score than enhanced T1 WI(P <0.05)through paired sample t test.After radiotherapy,SWI found 98 lesions (mean score 1.47±0.1 1 )and en-hanced T1 WI found 140 lesions (mean score 1.80±0.07),enhanced T1 WI had significantly higher score than SWI(P <0.05).Con-clusion SWI is superior to contrast-enhanced T1 WI to show the metastases before radiotherapy and can show tumor vascular in brain metastases obviously.SWI is inferior to enhanced T1 WI after radiotherapy.It has some value and may provide a new method for evaluating effects of radiotherapy.