BACKGROUNDHemangiopericytomas (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.

METHODSSeventeen 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.

RESULTSThe 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).

CONCLUSIONSCT 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.

Adult ; Aged ; Female ; Hemangiopericytoma ; diagnosis ; diagnostic imaging ; Humans ; Immunohistochemistry ; Male ; Meningioma ; diagnosis ; diagnostic imaging ; Middle Aged ; Tomography, X-Ray Computed ; methods

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.
Adult ; Hemangiopericytoma ; diagnosis ; Humans ; Male ; Retroperitoneal Neoplasms ; diagnosis

BACKGROUNDUsing magnetic resonance imaging, diagnosis of malignant meningioma from benign meningioma with atypical features is uncertain. We evaluated the value of lipid signal in differentiating intracranial meningiomas.

METHODS1H-magnetic resonance spectroscopy (MRS) using a point resolved spectroscopy (TR/TE 1000/144 ms) sequences were performed on 34 patients on a 3.0 T scanner. Lipid peak located at 1.3 ppm was evaluated. MRS data from these tumours were compared with histopathological findings (including hematoxylin and eosin staining and KP-1 staining).

RESULTSTwenty-nine meningiomas were histologically benign (eleven meningothelial, thirteen fibrous, four transitional and one microcystic), three were atypical, and two were anaplastic. Lipid signal was detected in ten cases: two anaplastic, three atypical, two fibrous and three meningothelial meningiomas. All voxels with lipid peak in the spectrum from the tumour were evaluated. With creatinine peak in the normal white matter chosen as internal standard, lipid/creatinine ratios of anaplastic, atypical and benign meningiomas were 0.844 +/- 0.027 (range from 0.725 to 0.994), 0.465 +/- 0.023 (range from 0.239 to 0.724), and 0.373 +/- 0.016 (range from 0.172 to 0.571) respectively. Highly significant differences were noted between anaplastic and the other two subtypes. Patchy necrosis was observed in anaplastic meningioma, while focal necrosis was noted in atypical meningioma with HE stain. However, no necrosis was found in benign group. KP-1 stain demonstrated histocytes containing lipids in the necrotic region of anaplastic and atypical meningioma.

CONCLUSIONThe lipid signal at 1.3 ppm is a useful marker in evaluating the malignancy of intracranial meningiomas, especially in the differential diagnosis of anaplastic meningioma.

Adult ; Female ; Humans ; Magnetic Resonance Imaging ; methods ; Magnetic Resonance Spectroscopy ; methods ; Male ; Meningeal Neoplasms ; diagnosis ; Meningioma ; diagnosis ; Middle Aged ; Reproducibility of Results ; Sensitivity and Specificity

OBJECTIVETo explore the relationship between clinical ischemic events and carotid calcification detected by 64 slices CT angiography.

METHODSWe 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.

RESULTSA 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).

CONCLUSION64 slices CT angiography can analyze the characterization of carotid plaque calcium.

Age Factors ; Aged ; Calcinosis ; complications ; diagnostic imaging ; epidemiology ; Carotid Stenosis ; complications ; diagnostic imaging ; Humans ; Incidence ; Middle Aged ; Myocardial Ischemia ; complications ; diagnostic imaging ; Retrospective Studies ; Tomography, Spiral Computed ; methods