Microvascular permeability of brain astrocytoma with contrast-enhanced magnetic resonance imaging: correlation analysis with histopathologic grade / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>The degree of pathological microvascular proliferation is an important element in evaluation of the astrocytoma grade. This study was aimed to quantitatively assess the microvascular permeability of brain astrocytoma with the volume transfer constant (K(trans)) and volume of extravascular extracellular space per unit volume of tissue (Ve) from dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) and to evaluate the effectiveness of the K(trans) and Ve in the grading of astrocytoma.</p><p><b>METHODS</b>The highest values of the K(trans) and Ve of 67 patients with astrocytoma (27 with grade II, 12 with grade III, and 28 with grade IV) were obtained. The comparisons of the differences of the K(trans) and Ve between the different grades were conducted using the Mann-Whitney rank-sum tests. Spearman's rank correlation coefficients were determined between K(trans) values, Ve values and astrocytoma grades. Receiver operating characteristic (ROC) curve analyses were performed to determine the cut-off values for the K(trans) and Ve to distinguish between the different grades of astrocytoma.</p><p><b>RESULTS</b>There were significant differences (P < 0.001) between the different grades in the K(trans) values and Ve values, except for grades III and IV. The K(trans) values and Ve values were both correlated with astrocytoma grades (both P < 0.001). The ROC curve analyses showed that the cut-off values for the K(trans) and Ve provided the best combination of sensitivity and specificity in distinguishing between grade II and grade III or IV astrocytomas.</p><p><b>CONCLUSIONS</b>DCE-MRI can play an important role in assessing the microvascular permeability and the grading of brain astrocytoma.</p>

Retroperitoneal hemangiopericytoma: case report and literature review / 中华医学杂志(英文版)

Retroperitoneal hemangiopericytoma is a kind of uncommon tumor. We report a case of 41-year-old man who was diagnosed retroperitoneal tumor without significant symptoms by abdominal ultrasonography. Abdominal CT and MRI scans show a 6 cm × 5 cm solid tumor delineated clearly from adjacent organs. Excision of the tumor was performed and the histopathological examination confirmed the diagnosis of hemangiopericytoma.

Quantitative evaluation of benign meningioma and hemangiopericytoma with peritumoral brain edema by 64-slice CT perfusion imaging / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>Hemangiopericytomas (HPCs) have a relentless tendency for local recurrence and metastases, differentiating between benign meningiomas and HPCs before surgery is important for both treatment planning and the prognosis appraisal. The purpose of this study was to evaluate the correlations between CT perfusion parameters and microvessel density (MVD) in extra-axial tumors and the possible role of CT perfusion imaging in preoperatively differentiating benign meningiomas and HPCs.</p><p><b>METHODS</b>Seventeen patients with benign meningiomas and peritumoral edema, 12 patients with HPCs and peritumoral edema underwent 64-slice CT perfusion imaging pre-operation. Perfusion was calculated using the Patlak method. The quantitative parameters, include cerebral blood volume (CBV), permeability surface (PS) of parenchyma, peritumoral edema among benign meningiomas and HPCs were compared respectively. CBV and PS in parenchyma, peritumoral edema of benign meningiomas and HPCs were also compared to that of the contrallateral normal white matter respectively. The correlations between CBV, PS of tumoral parenchyma and MVD were examined.</p><p><b>RESULTS</b>The value of CBV and PS in parenchyma of HPCs were significantly higher than that of benign meningiomas (P < 0.05), while the values of CBV and PS in peritumoral edema of benign meningiomas and HPCs were not significantly different (P > 0.05). MVD in parenchyma of HPCs were significantly higher than that of benign meningiomas (P < 0.05). There were positive correlations between CBV and MVD (r = 0.648, P < 0.05), PS and MVD (r = 0.541, P < 0.05) respectively. Furthermore, the value of CBV and PS in parenchyma of benign meningiomas and HPCs were significantly higher than that of contrallateral normal white matter (P < 0.05), the value of CBV in peritumoral edema of benign meningiomas and HPCs were significantly lower than that of contrallateral normal white matter (P < 0.05), while the value of PS in peritumoral edema of benign meningiomas and HPCs were not significantly different with that of contrallateral normal white matter (P > 0.05).</p><p><b>CONCLUSIONS</b>CT perfusion imaging can provide critical information on the vascularity of HPC and benign meningiomas. Determination of maximal CBV and corresponding PS values in the parenchyma may be useful in the preoperative differentiating HPC from benign meningiomas.</p>

Association between clinical ischemic events and carotid calcification evaluated by 64 slices CT angiography / 中华心血管病杂志

<p><b>OBJECTIVE</b>To explore the relationship between clinical ischemic events and carotid calcification detected by 64 slices CT angiography.</p><p><b>METHODS</b>We retrospectively analyzed the carotid calcified plaques in 116 patients underwent the 64 slices CT angiography. The relationship between the carotid calcification and the clinical ischemic events was analyzed.</p><p><b>RESULTS</b>A total of 377 plaques were detected and the incidence of carotid plaque calcification was 63.40%. Incidence of plaque calcification was significantly lower in patients with ages < 50 years than that in patients with ages 51 - 59 years, 60 - 69 years and higher than 70 years (P = 0.003, P = 0.002, P = 0.000, respectively). The incidence of plaque calcification in the common carotid artery was significantly lower than the carotid bifurcation (P = 0.000) and the internal carotid artery (P = 0.000). The incidences of calcification in the mild, moderate and severe degree of stenosis and occlusion were 46.54%, 33.33%, 26.67% and 0% respectively. The distribution of intraplaque calcium was similar between patients with ischemic event and non-ischemic event group. However, the incidence of calcification was significantly lower patients with ischemic event than that in patients without ischemic event (30.34% vs. 43.10%, P = 0.013). Calcified plaque was negatively associated with ischemic event (beta = -0.688, P = 0.006).</p><p><b>CONCLUSION</b>64 slices CT angiography can analyze the characterization of carotid plaque calcium.</p>

Imaging characteristics of intraparenchymal schwannoma and the related pathology / 中华放射学杂志

Objective To Analyze the imaging characteristics of intraparenchymal schwannoma and the related pathology,in order to improve the accuracy of diagnosis and be in favor of the clinics and the prognosis.Methods Four cases were confirmed to be intraparenchymal schwannoma by pathological and immunohistochemistry examination.One case was examined with precontrast and enhanced CT scanning,one with unenhanced MRI scanning,two with unenhanced and enhanced CT and MRI scanning.Their images were retrospectively analyzed.Results Of the four cases,three patients were less than 30 years old,with tumors located supratentorially.Cysts were found in all cases,with nodules on the wall in 3 cases.The nodules were enhanced markedly in two cases and moderately in one ease.In addition,calcification was detected in one case and prominent peritumoral edema existed in 1 case.The picture of the pathology demonstrated Antoni type A and Antoni type B.Immunostaining showed intense immunoreactivity for S-100 protein and Vim and negative immunoreactivity for GFAP and EMA.Conclusions Intraparenchymal schwannoma mostly occurred in juvenile,which located supratentorially in most cases.The presence of a cyst and peritumoral edema together with the tumor appears to be characteristic of intraparenchymal schwannoma.Calcification or the enhanced nodule is the helpful sign for the diagnosis.Combining the imaging findings with the pathology and immunohistochemistry results can gain the accurate diagnosis.