Objective To study the multi-slice computed tomography (MSCT) features of pancreatic neuroendocrine tumors (PNET).Methods In the retrospective study,30 histologically verified pancreatic neuroendocrine tumors were incidentally detected with contrast enhanced MSCT.Various CT findings such as location,size,pattern,enhancement were analyzed.All tumors were graded as G1 to G3 according to WHO classification in 2010.Results There were 30 lesions in 30 patients with histologically confirmed PNET,including 16 lesions in G1,6 lesions in G2,and 8 lesions in G3.16 lesions were located in head of pancreas,8 lesions located in pancreatic body,and 6 lesions located in tail of pancreas.16 tumors were solid,3 tumors predominantly cystic,and 11 lesions solid and cystic.Calcification was observed in 6 cases.There was no significant difference in tumor location,size,solid or cystic,calcification among the different pathological grades of the tumor.CT values in patients with G1 PNETs in arterial,portal and delay phase were higher than those in patients with G3 PNETs (P＜0.05).Conclusion Dynamic enhancement CT may provide useful information to preoperative grading of PNET and tumors in a higher grade may show poorer enhancement.

Objective To investigate the incidence and predictors of cerebral infarction in patients with ruptured ACoA aneurysms, and to provide diagnostic and therapeutic information.Methods A total of 319 patients with ruptured ACoA aneurysms in our hospital from January 2009 to February 2015 were reviewed in this study. The author collected data regarding clinical characteristics, and measured the aneurysm morphologies on CTA images. Age, flow angle, vessel angle were analyzed by independent-samples t tests in patients with or without cerebral infarction. Mann-Whitney U tests were used for aneurysm size, aneurysm height, perpendicular height, neck size, size ratio, aspect ratio, aneurysm angle , World Federation of Neurosurgical Societies (WFNS) grade at admission and Fisher grade. Chi-square tests and Fisher's exact tests were used for sex, histories of hypertension, smoking and stroke, treatment modalities, anterior cerebral A1 segment configuration and angiographic vasospasm on CTA images. The multivariate logistic regression analyses were used to determine the independent risk factors of cerebral infarction using the stepwise regression method. Results Of the 319 patients, there were 253 without and 66 patients with cerebral infarction. Differences of age(53±11 vs 57±12,respectively;t=-2.415, P=0.016), Fisher grade [Ⅰ 23(9.1%), Ⅱ 27(10.7%), Ⅲ 74(29.2%), Ⅳ 129(51.0%) vs Ⅰ 1(1.5%), Ⅱ 7 (10.6% ), Ⅲ 13(19.7% ), Ⅳ 45(68.2% ), respectively;Z=-2.541, P=0.035] and treatment modalities [endovascular coil embolization 155(61.3% ), neurosurgical clipping 98(38.7% ) vs endovascular coil embolization 23(34.8%), neurosurgical clipping 43(65.2%), respectively;χ2=14.810, P<0.001] reached statistical significance. Multivariate analysis showed that Fisher grade Ⅳ(OR=10.36,95%CI 1.34-80.29, P=0.025) and neurosurgical clipping (OR=3.28, 95% CI 1.84-5.86,P<0.001)still had statistical significance. Conclusions Cerebral infarction in patients with ruptured ACoA aneurysms may be associated with Fisher grade and treatment modalities. Although there is difference between the two groups in age, it is not a predictor of the occurrence of cerebral infarction.

Objective To evaluate the clinical value of enhanced 3D-SPACE-STIR sequence MR in brachial plexus injury post-ganglionic nerve.Methods Eighteen patients with suspected brachial plexus injury were examined by routine MRI,3D-SPACE-STIR sequence and enhanced scan.The position,morphology,signal intensity of the brachial plexus injury and its relation with the proximal and distal portions of the brachial plexus were evaluated by senior radiologists.The image quality of plain and enhanced 3D-SPACE-STIR was evaluated respectively.Results The CNR of plain scan and enhanced 3D-SPACE-STIR sequence images were 32.31+2.98 and 43.66+2.78 respectively and the difference was statistically significant.Plain and enhanced 3D-SPACE-STIR sequences of supraclavicular nerves display rate were 95.0% and 96.1% respectively without having statistically significant difference.However,the subclavicular segment of the brachial plexus showed the displaying rates of 66.7% and 94.4% and the difference was statistically significant.Moreover, the background suppression effect of enhanced scan was better than that of the plain scan.Conclusion Enhanced 3D-SPACE-STIR sequence can clearly show brachial plexus injury,and its image quality is better than that of the plain scan,which can provide important imaging basis for accurate diagnosis of brachial plexus injury.