Objective To explore the application value in distinguishing the postoperative intracranial abscess from the spontaneous intracranial abscess using diffusion-weighted imaging(DWI).Methods Total of 73 patients with intracranial abscess,including 30 patients with spontaneous intracranial abscess and 43 patients with postoperative intracranial abscess underwent DWI scan.The clinical data and apparent diffusion coefficients (ADC)values were analysed using Mann-Whitney and χ2tests between the two groups,and χ2automatic interaction detection analysis was used to classify the ADC values into categories in each group.Results The ADC value of the postoperative intracranial abscess(median,1.34 ×10 -3mm2/s;interquartile range,1.00-1.62×10 -3mm2/s)was significant higher than that of the spontaneous intracranial abscesses (median,0.68×10-3mm2/s;interquartile range,0.58-0.79 ×10-3mm2/s;P<0.001).Theχ2 automatic interation detection analysis showed that 24 patients (80%)were found to be spontaneous abscess with ADC values less than 0.79×10-3mm2/s,the other 6 patients (20%)were found to be spontaneous abscess with ADC values between 0.79 and 1.33× 10-3mm2/s,and no patietns were found bo be spontaneous abscess with ADC values greater than 1.33×10-3mm2/s(P<0.001). Conclusion DWI has certain application value in distinguishing the postoperative intracranial abscess from the spontaneous intracranial abscess.

Objective To explore the clinical effect of endoscopic-assisted intraoral reduction mandibuloplasty.Methods From January 2010 to December 2014,a total of 186 patients with prominent mandibular angles underwent one stage long-curved ostectomy combined with splitting corticectomy through an intraoral approach with endoscopic assistence according to preoperative design for reduction mandible three-dimensionally,and achieved reduced width of the lower face with smooth curve of mandibular edge.The distance between both gonions was measured and the complications recorded to evaluate the clinical effect of the surgery during follow-up.Results All the 186 patients had no complications of bleeding and infection.The mean distance between both gonions measurement was (117.3±2.5) mm before surgery and (102.6±2.3) mm after operation;it was reduced (14.1 ±2.4)mm.After 1 month to 2 years of follow up,the width of the lower face was reduced in the frontal view and the mandibular angle appeared natural and inconspicuous in the lateral view.The patients were satisfied with both their frontal and lateral appearances.Conclusions Intraoral approach mandibular ostectomy with endoscopic-assisted allows surgeons to perform accurate,safe and reproducible ostectomies and to recontour mandible symmetrically and reduce the complications.