Objective To evaluate the usefulness of MR imaging in follow-up of osteosarcomas treated with high intensity focused ultrasound (HIFU). Methods The images of nonenhanced and multiphase gadolinium-enhanced MR imaging before and after HIFU treatment in 16 patients with osteosarcomas pathologically confirmed were interpreted prospectively and correlated with the results of ~ 99mTc-MDP bone scan. Results The results of HIFU in 14 osteosarcomas were evaluated correctly. Before HIFU, 16 osteosarcomas demonstrated hypointensity on T1WI and heterogenous hyperintensity on T2WI and obvious enhancement during capillary and delayed phases and abnormal radioactivity accumulation were detected.One to Four weeks after HIFU treatment, the osteosarcomas became slightly hyperintense on T1WI and heterogenously hyperintense on T2WI, and no enhancement during capillary and delayed phase was noted. There was a clear boundary presenting between the targeted and untreated areas, and abnormal radioactivity accumulation disappeared. Both the signal intensity on T2WI and the tumor size reduced gradually after HIFU treatment 3 to 25 months. Conclusion HIFU is an effective local therapy for osteosarcomas, and MRI can accurately evaluate the efficacy of HIFU.

Objective To examine the reliability and validity of compensative neurosis assessing scale (CNAS) and in order to develop the quantitative assessing method for distinguishing the compensation neurosis from malingering and typical neurosis. Methods The reliability and validity of the scale was tested based on the subjects including the cases involved forensic problems, the patients with typical neurosis in general psychiatric 0.944. The test-retest reliability was more than 0.820. The scorer reliability was more than 0. 812. The total accu-racy rate of CNAS for evaluating three groups of subjects based on the experts diagnosis, and with 91.2% of speci-ficity and 79.3% of sensitivity for evaluating compensation neurosis. Condusion The CNAS has acceptable psy-chometrics properties on reliability and validity. It will provide method to distinguish the compensation neurosis from malingering and typical neuroses.

Objective To investigate clinical features,diagnosis,clearance strategies and prognosis of intracranial foreign bodies.Methods Twenty patients with intracranial foreign bodies were analyzed retrospectively,together with review of the related literatures.Results Twenty patients underwent craniotomy for intracranial foreign body removal under guidance of preoperative CT and X-ray localizations and intraoperative C-arm X-ray machine and ultrasound localizations.A total of 35 foreign bodies were removed.One patient underwent second surgical resection after the incomplete removal due to displacement of intracranial foreign bodies.According to Glasgow outcome score (GOS) at discharge,the outcomes were good (GOS =4-5 points) in 16 patients,poor (GOS =2-3 points) in three and death (GOS =1 point) in one.Conclusions CT and X-ray locations before surgery and C-ann X-ray machine and ultrasound locations in operation avail the removal of foreign bodies by craniotomy.In the meantime,prognosis is satisfactory.

Objective To investigate the accuracy and application value of the Tada formula in evalua-ting the meningioma volume based on 3D reconstruction technology.Methods The thin-slice magnetic reso-nance images of 297 patients with meningioma treated in the neurosurgery department of 940 Hospital of PLA Joint logistics Support Force from January 2014 to May 2022 were retrospectively analyzed.The meningioma volume was evaluated by the Tada formula method and three-dimensional reconstruction method respectively.The accuracy of the evaluation of meningeal tumor volume by the Tada formula was analyzed by grouping sta-tistics.Results In the whole sample and the concentrated sample,the obtained meningioma total volumes had no statistical difference between the two methods(P＞0.05),the Spearman correlation coefficients were 0.995 and 0.993 respectively,and the intragroup correlation coefficients(ICC)were 0.992 and 0.989,respec-tively.In the Bland-Altman plot,most of the data points were within the limit of uniformity.Compared with different groups,the Tada formula had a slightly lower accuracy in the volume assessment of meningiomas with higher degree of irregularity,and a better accuracy in the volume assessment of supratentorial meningio-mas than subtentorial meningiomas.Conclusion The Tada formula could accurately evaluate the volume of meningioma,and it could be used as a preliminary method to evaluate meningioma volume in clinic

Objective:To explore the application of mobile augmented reality (mAR) technology in the teaching of neuroanatomy, and to observe its effect on students' academic performance and cognitive load.Methods:By collecting and designing various neuroanatomy multimedia teaching resources (graphics, animations and videos), using augmented reality (AR) marker-based image recognition technology, the multimedia resources were placed at the tags in the traditional book pages to make the books interactive. And various multimedia resources were combined with traditional printed books through mobile devices. Forty students were randomized into the experimental group or the control group. The experimental group was taught with mAR multimedia materials, and the control group adopted traditional teaching methods. After a 6-hour course was completed, all students had a unified test, and the academic performance test and the PAAS(platform-as-a-service) cognitive load scale were used for data collection and analysis. The variance analyses (MANOVA and ANOVA) were used for significance testing.Results:One-way MANOVA test was used to determine the learning effect of mAR on academic performance and cognitive load. The results showed that there was a significant difference between the experimental group and the control group ( P<0.05). The univariate ANOVA test found that the experimental group students who learned neuroanatomy through mAR had better test scores than the control group students. In addition, compared with the control group students, the cognitive load of students in experimental group was significantly reduced, with statistical significance (all P<0.05). Conclusion:Through the teaching practice, we found that using mAR to learn neuroanatomy helps students improve their academic performance while reducing their cognitive load.