Objective To explore the value of MRI histogram analysis in the risk assessment of medulloblastoma recur rence.Methods The data of 28 patients pathologically confirmed of medulloblastoma was analyzed retrospectively.All patients were divided into recurrent group and the non recurrent group (each n=14).The ROIs were drawn on the maximum level of enhanced MR sagittal images,and the histogram analysis were performed using the software named Mazda.The statistical analysis was performed on the histogram parameters to find out the different characteristics between the two groups,and the ROC curve was drawn to evaluate its diagnostic efficacy for recurrence of medulloblastoma.Results In all of the 9 parameters which are extracted from histogram,kurtosis had statistical significance between the 2 groups (P=0.018).The area under the ROC curve was 0.776 (P=0.018),and the sensitivity and specificity of kurtosis in the risk assessment of medulloblastoma recurrence were 64.3％ and 71.4％,respectively.Conclusion MRI histogram analysis can be an important method to assess the risk of medulloblastoma recurrence.

Objective To explore the MRI features of cavernous hemangioma in the thoracic spinal epidural space,to improve the recognition of the disease.Methods The clinical,pathological and MRI data of 7 cases with cavernous hemangioma in the thoracic spinal epidural space confirmed by surgery and pathology were analyzed retrospectively.Results 7 cases of cavernous hemangioma in the thoracic spinal epidural space were included in our study,all cases underwent MRI contrast enhancement examination and 6 of them underwent conventional MRI examination.On T1WI,4 cases showed hypointensity,2 cases showed slightly hypointensity and 1 case showed mixed slightly hypointensity.On T2WI,5 cases showed slightly hyperintensity,1 case showed slightly hypointensity. On fat suppression sequence,5 cases showed hyperintensity,1 case showed heterogeneous hyperintensity.On diffusion-weighted imaging (DWI),7 cases showed obviously hyperintensity.On contrast-enhanced images,the lesions enhanced homogeneously in 5,enhanced heterogeneously in 2.Conclusion MRI can display the location,appearance and enhancement pattern of thoracic spinal epidural cavernous hemangioma distinctly,while definite diagnosis of which still depends on pathology.

Objective To study the value of whole tumors T2WI gray histogram analysis for differential diagnosis of three commonly presented pediatric posterior fossa tumors. Methods A retrospective analysis was conducted to compare brain MRI examination and pathology diagnosis of 133 cases of posterior fossa tumors in pediatric patients in our hospital.Among them, there were 49 cases of ependymoma(there were 25 males and 24 females), 36 cases of astrocytoma(WHO grade Ⅰ)(there were 19 males and 17 females), 48 cases of medulloblastoma(there were 36 males and 12 females),aged 1 to 14 years old, with an average (7±2) years old. Respectively draw the region of interest (ROI) in the T2 MR transaxial images of three groups on each layer of tumor level by using Mazda software and analyze the whole tumors gray histogram, including mean,variance, kurtosis,skewness, perc.01%,perc.10%,perc.50%,perc.90% and perc.99%.The histogram parameters of the three groups were not normally distributed. The Kruskal-Wallis test was used to compare the three groups. Bonferroni test was used to compare the two groups to find out statistical significance of each parameter. Results Through histogram analysis of 9 parameters, these 9 parameters were statistically significant (all P <0.05),including mean,variance,kurtosis,skewness, perc.01%,perc.10%,perc.50%,perc.90% and perc.99%. The sensitivity of skewness to differentiate ependymoma and the astrocytoma was 69.4％, the specificity was 77.8％, the area under the curve was 0.744, and the best cut-off value was-0.08. The sensitivity of kurtosis to differentiate astrocytoma and the medulloblastoma was 95.8％, the specificity was 97.2％ and the area under the curve was 0.972, the cut-off was 1.68. The sensitivity of kurtosis to differentiate ependymoma and the medulloblastoma was 91.7％, the specificity was 89.8％and the area under the curve was 0.932,the cut-off was 1.90.They had a high identification efficiency. Conclusions The T2WI gray histogram analysis based whole tumors is helpful for the dignosis of three types of pediatric posterior fossa tumors. Skewness has a high diagnostic efficiency to differentiate ependymoma and the astrocytoma. Kurtosis has a high diagnostic efficiency to differentiate ependymoma and the medulloblastoma. Kurtosis has a high diagnostic efficiency to differentiate ependymoma and medulloblastoma.

Objective To study the value of whole tumors volume based apparent diffusion coefficient histogram analysis in grading diagnosis of ependymoma. Methods Seventy?one patients with ependymal tumors were retrospectively analyzed, including 13 cases of WHOⅠ, 28 cases of WHOⅡ, 30 cases of WHO Ⅲ. Regions of interest (ROI) in the apparent diffusion coefficient maps of three groups on each layer of tumor level were drawn by using MaZda software and were analyzed using the whole tumors gray histogram. The histogram parameters of the three groups all fitted the normal distribution and homogeneity test of variance. The ANOVA analysis was used to compare the three groups. LSD-t test was used to compare the two groups to find out statistical significance of each parameter. Results Through histogram analysis of 9 parameters, three parameters were statistically significant (P<0.05), including variance, perc. 01％ and perc. 10％. The remaining 6 parameters had no significant difference between the three groups (P>0.05). Between the WHOⅠand the WHOⅡ, the sensitivity of perc.10％was 85.7％, the specificity was 87.7％, the area under the curve was 0.835, and the best cut-off value was 131.33. Between the WHOⅠand the WHOⅢ, the sensitivity of perc.10％was 85.7％, the specificity was 100.0％, the area under the curve was 0.872, and the cut-off was 126.5.Between the WHOⅡand the WHOⅢ, the sensitivity of variance was 68.4％, the specificity was 79.6％, the area under the curve was 0.794, and the cut-off was 2645.7. They had a high identification efficiency. Conclusion Whole-tumor histogram analysis of apparent diffusion coefficient maps could provide ancillary diagnostic value in grading diagnosis of ependymoma. Perc.10％and variance had a high diagnostic efficiency.

Humans ; Cardiac Resynchronization Therapy ; Cardiac Pacing, Artificial ; Heart Ventricles ; Heart Failure/therapy* ; Treatment Outcome ; Electrocardiography ; Ventricular Function, Left