Objective To investigate the diagnostic value of susceptibility weighted imaging ( SWI) in patients with mild traumatic brain injury(MTBI).Methods From June 2016 to October 2017,a retrospective analysis of 89 patients with MTBI (Glasgow score 13 to 15) in the First People's Hospital of Xiaoshan District was conducted.All patients were given head CT ,MRI and SWI within 1 week after admission.Combined with CT and phase diagram ,after removing blood vessels ,calcification and skull base artifact ,the low signal intensity on the SWI was cerebral contusion and hemorrhage.The sites,the number and the size of lesion detected on CT ,MRI and SWI images were recorded and analyzed with clinical symptoms.Results According to the presence or absence of clinical symptoms in the group ,the detection rates of microbleeds hemorrhage in patients with traumatic cerebral by SWI were 94.4%,54.2%,100.0%, 95.5%,respectively,which were higher than those by CT (16.6%,4.2%,15.0%,4.5%) and MRI conventional sequences(33.3%,8.3%,20.0%,13.6%),the differences were statistically significant (χ2＝6.633,P＝0.010;χ2＝4.260,P＝0.039,all P ＜0.05),especially in MTBI patients with a history of transient coma or persistent clinical symptoms after trauma(the detection rate was 100.0%).Conclusion Compared with conventional CT and MRI,the micro-contusion and small hemorrhagic lesions of SWI is more accurate and important in the diagnosis of MTBI,and has a significant prognostic value for clinical treatment and judgment of patients with MTBI .

Objective To establish a three-dimensional visualization model of complex anal fistula based on high-resolution mag-netic resonance imaging(HR-MRI),and to explore its feasibility and clinical application value.Methods The clinical and imaging data of 26 patients with complex anal fistula were analyzed retrospectively,and a three-dimensional visualization model based on HR-MRI images was established.The Parks typing,internal orifice,external orifice,branch fistula and abscess were evaluated by radiolo-gists and anorectal surgeons in HR-MRI images and the three-dimensional visualization model,and the SPSS 22.0 software was used to analyze the assessment results against the clinical surgery one by one.Results A total of 26 patients had 17 trans sphincteric fis-tulas,7 inter sphincteric fistulas,and 2 suprasphincteric fistulas,and the accuracy of Parks typing based on HR-MRI images and three-dimensional visualization model was 100％;26 patients had a total of 33 internal orifices,and the evaluation of internal orifices based on HR-MRI images was better than that of three-dimensional visualization model(P=0.180 vs P=0.022);15 patients had a total of 32 external orifices,and the evaluation of external orifices based on three-dimensional visualization model was better than that of HR-MRI images(P=0.791 vs P=0.049);20 patients had perianal abscesses,and the evaluations based on HR-MRI images and three-dimensional visualization model were both highly accurate(P=0.549 vs P=0.625);18 patients with branch fistula,the evaluation of branch fistula based on three-dimensional visualization model was significantly better than that of HR-MRI images(P=1.000 vs P＜0.001).Conclusion Based on three-dimensional visualization model of HR-MRI,the evaluation of complex anal fistula Parks typing,external orifice,branch fistula and abscess is more accurate,which is worthy of further research and promotion.