Objective To establish a stable model of intraluminal thread approach in making focal cerebral ischemia/reperfusion modelin rabbit.Methods Forty New Zealand white rabbits were randomly divided into three groups:A,B,and C.Angiography of ICA wasperformed in group A(n=5). Control group B(n=5) was sham-operated.In group C(n=30),the focal cerebral ischemia/reperfusionmodel was made by inserting a wire ( d=0.45 mm ) into MCA through ICA and CCA directly and pulling it out 3 hours later . MRI andneurological deficit score were used to evaluate the effectiveness of models.Results Angiography could show the course and bifurcation of ICA clearly.22 models were successful.The pathological changes were shown on MRI.The neurological deficit score (reperfusion 1 h) were 2.8?0.45.Conclusion The focal cerebral ischemia/reperfusion model made by inserting a wire(d=0.45 mm) into MCA through ICA and CCA directly and pulling it out 3 hours later was stable and fit for imaging research.

Objective To evaluate the value of magnetic source imaging(MSI) in localizing the epileptic foci of patients with histologically proved grey matter heterotopia(GMH) and seizure. Methods MSI examinations were performed on 8 patients with GMH and seizure. The location of the epileptic foci defined by MSI was compared with the results of the ECoG. After imaging examinations, all patients received operation with 13-48 months follow up to observe the effectiveness of the operation. Results Among the 8 patients, 1 had hippocampal sclerosis,2 had focal cortical dysplasiaof type Ⅰ B and 1 had focal cortical dysplasia of type Ⅱ B. MRI showed normal findings in 2 cases, subcortical heterotopia in 4 cases, and nodulor heterotopia in 2 cases with one having schizencephaly. The epileptic foci defined by MSI were at right temporal lobe in 2 cases, left frontal lobe in 2 cases, biparietal lobe in1 case, left parietal lobe in 1 case, left temporal lobe in 1 case, and left frontal-parietal lobe in 1 case. The epileptic foci defined by MSI were completely overlaid with area of GMH in 4 cases, closely behind the area of GMH in case, and partly overlaid with area of GMH in 1 cases with size larger than that of the latter. One patient showed two epileptic foci with one located within the area of GMH and the other one 2 centimeters anterior to the area of GMH.One case's epileptic focus located 2 centimeters posteolateral to the area of GMH . The locations of the epileptic foci defined by MSI showed no difference with those defined by ECoG in all patients. According to Engel classification of treatment effect of epilepsy, 6 patients achieved Engle class Ⅰ ( seizure free after operation ), and 2 patients Engel class Ⅳ ( no changes in the frequcenty of occurrence of seizures before and after operation ). Conclusion MSI can noninvasively and precisely localize the epileptic foci before operation in patients with GMH and seizure.

PurposeTo explore the value of gemstone spectral imaging (GSI) in diagnosis of thyroid nodule hemorrhage.Materials and Methods Seventeen patients with surgery and pathology confirmed thyroid nodule hemorrhage underwent thyroid spectrum CT scan. The CT value, iodine concentration value, water concentration value and the effective atomic ordinal value as well as spectral curve slope of hemorrhagic nodules and surrounding normal thyroid tissue were measured respectively.Results Hemorrhagic thyroid nodules showed equal or high CT value, low concentration of iodine, high concentration of water, low spectral curve slope, and low effective atomic ordinal value on spectral CT imaging. There were statistically significant differences in concentration of iodine value, concentration of water value, and spectral curve slope between hemorrhagic nodules and surrounding normal thyroid tissue (Z=-5.438,-4.679 and-5.317,P<0.01), and there were statistically significant differences in CT value and effective atomic ordinal value (Z=-2.097 and-2.230,P<0.05).Conclusion Energy spectrum CT scan is important in detection and accurate diagnosis of thyroid nodule hemorrhage.

Objective To study the MRI features of pituitary lesions in children with short stature caused by growth hormone de-ficiency.Methods The MRI findings of clinical and pathological confirmed pituitary lesions in 40 children were retrospectively re-viewed.All cases had 3.0T MRI examination.Results The pituitary lesions included hypoplasia of antehypophysis (25 cases),pitu-itary stalk interruption syndrome (3 cases),pituitary atrophy after craniopharyngioma excision (2 cases)and pituitary hyperplasia (10 cases).MRI of antehypophysis hypoplasia showed that the height of antehypophysis was less than normal.Pituitary stalk inter-ruption syndrome showed not only hypoplasia of antehypophysis,but also absence or marked thinning of pituitary stalk and ectopic bright signal of posterior pituitary lobe on T1 WI.Atrophy of the pituitary was seen after resection of craniopharyngioma,and the stalk was unclear.All of the pituitary hyperplasia were caused by hypothyroidism.MRI of pituitary hyperplasia displayed antehy-pophysis enlargement and upward apophysis symmetrically.There were no pituitary stalk interruption,translocation and abnormal signal.The pituitary hyperplasia had obvious homogeneous enhancement.Pituitary gland reduced in size after replacement therapy. Conclusion MRI can show the features of pituitary lesions in children with short stature caused by growth hormone deficiency clear-ly.Correct diagnosis can be made and the therapeutic effect can be monitored combining with clinical manifestation.

Objective To assess the diagnostic value of magnetic source imaging(MSI) in the preoperative localization of focal cortical dysplasia(FCD). Methods Eighty-two patients with intractable epilepsy resulting from FCD undergone preoperative assessment including MSI, video electroencephalography(VEEG) and electrocorticography(ECoG)from February 2006 to June 2012.The consistency between pre- and intra-surgical assessment was evaluated. For patients who had consistent results,postoperative curative effect was also recorded. The accuracy and predictive values of noninvasive preoperative tests were compared by χ2 test. Results For MSI and ECoG, their results were consistent in 57 cases, partially consistent in 14 cases, and inconsistent in 11 cases. In the postoperative follow-up of 57 patients with consistent results, there were 46 cases with Engel class Ⅰ, 3 cases with Engel class Ⅱ, 4 cases with Engel class Ⅲ, and 4 cases with Engel class IV. For VEEG and ECoG, the results were consistent in 43 cases, partially consistent in 33 cases, inconsistent in 6 cases.The postoperative follow-up showed that 27 cases were graded as Engel classⅠ, 5 cases as Engel classⅡ,7 cases as Engel classⅢ, and 4 cases as Engel class IV. There were statistically significant differences(χ2=5.023,P=0.025)of the concordance rate with ECoG between MSI(69.51%,57/82)and VEEG(52.44%,43/82). In the postoperative follow-up of patients with consistent results, the curative effect was better in group MSI than in group VEEG (χ2=3.989,P=0.046). Conclusions Preoperativelocalization by MSI shows advantage over VEEG, which meanswhen it achieves an agreement with ECoG, patients with FCD may get better prognosis from the surgical process.