Purpose:To assess MRI and MRS features of intracranial hemangiopericytoma.Materials and Methods: The imaging data of MRI and MRS were analyzed retrospectively with seven cases of hemangiopericytoma.MR examinations were performed on seven cases,MRS on 4 cases.Results: The position of lesions were all located at the supratentorial area and extraaxial region.Six masses were lobulated in shape.Of seven cases,3 cases were isointense with cortical gray matter,3 iso- and hypointense,l hypointense with localized hyperintense resulted from hemorrhage on T1WI: 2 cases demonstrated isointense with cortical gray matter,4 iso- and hyperintense,1 complex hyperintense on T2WI.Five tumors had prominent internal or surficial serpentine signal voids.3 tumors showed homogeneous marked enhancement,4 heterogeneous enhancement.MRS of four tumors showed marked elevated Cho peak,Lip peak and diminished or disappeared NAA peak.Two cases were companied with marked elevated MI peak.Conclusion:The MR imaging findings of hemangiopericytoma has some characteristics,which can help differentiation from meningioma combined MRS.

Objective To investigate the CT characteristics of anaplastic thyroid carcinoma and evaluate the diagnostic value of CT in this disease.Methods The CT findings of 10 patients with pathologically proved anaplastic thyroid carcinoma were retrospectively reviewed.The patients included 7 females and 3 males.Their age ranged from 25.0 to 78 years with median of 61 years.Multi-slices plain and post contrast CT scans were performed in all patients.Results Unilateral thyroid was involved in 6 patients.Unilateral thyroid and thyroid isthmus were both involved in 2 patients due to big size.Bilateral thyroid were involved in 2 patients.The maximum diameter of anaplastic thyroid carcinoma ranged from 2.9-12.8 cm with mean of (4.5 ± 1.4) cm.All lesions demonstrated unclear margins and envelope invasion.The densities of all lesions were heterogeneous and obvious necrosis areas were noted on precontrast images.Seven lesions showed varied calcifications,and coarse granular calcifications were found in 5 lesions among them.All lesions showed remarkable heterogenous enhancement on post-contrast CT.The CT value of solid portion of the tumor increased 40 HU after contrast media administration.The ratios of CT value which comparing of the tumor with contralateral sternocleidomastoid muscle were 0.69-0.82 (0.76 ± 0.18)and 1.25-1.41 (1.33 ± 0.28)on pre and post CT,respectively.Enlarged cervical lymph nodes were found in 6 cases (60.0％).It showed obvious homogeneous enhancement or irregular ring-like enhancement on post-contrast images and dot calcifications were seen in 1 case.Conclusions Relative larger single thyroid masses with coarse granular calcifications,necrosis,envelope invasion,remarkable heterogeneous enhancing and enlarged lymph nodes on CT are suggestive of anaplastic thyroid carcinoma.

Objective To evaluate the feasibility and the clinical value of MRI in the diagnosis of small-bowel disease. Methods Sixty-three patients with suspected small-bowel diseases and 3 volunteers without signs of small bowel disease underwent MRI examination. Thirty-one patients whose diagnoses were confirmed by pathology or clinical results were categorized into two groups (neoplastic and normeoplastic). The conspicuity of bowel wall, the sensitivity of MRI in detecting small-bowel lesions, and the accuracy rate of diagnosis were calculated. The average bowel wall thickness between the two groups was assessed by using Wilcoxon signed-rank test. Enlarged mesenteric lymph nodes, mesenteric infiltration, and small-bowel stenosis were analyzed by using Fisher's exact test in each group respectively. Results MRI examinations of all 66 subjects were successfully performed. Images were rated on a continuous 4-peint scale. Sixty-two cases (93.9%) were scored as 2 or 3. The diagnoses of 31 patients (neoplastic group (n = 10) and nonneoplastic group (n = 21) were confirmed by pathology or clinical results. The sensitivity, accuracy of MRI in identifying small bowel diseases were 100% (31/31) and 77.4% (24/31) respectively. The average bowel wall thickness of the two groups was 23 mm(7.0-65.0 mm) and 5 mm(2.0-35.0 mm) respectively, and there was a statistically significant difference between the two groups (Z = - 2.949, P < 0.01). Enlarged lymph nodes in mesentery were found in 7 cases in neoplastic group and 4 cases in nonneoplastic group, and there was a statistically significant difference between the two group (P < 0.05). Small-bowel stenosis was depicted in 10 cases in both groups and there was a statistically significant difference between the two groups (P <0.01). The mesenteric infiltration sign was seen in 5 cases and 17 cases respectively, and showed no significant difference between the two groups (P > 0.05). Conclusion MRI can depict the location and extension of the small-bowel disease accurately and it is an effective method in the diagnosis of small-bowel disease.

Objective To assess the clinical value of 16-slice spiral CT in the diagnosis of multiple carcinomas in unilateral upper urinary system. Methods The imaging findings of 16-slice spiral CT of 10 patients suffered from multiple carcinomas in the unilateral upper urinary system proven pathologically were analyzed. Results Among 10 cases, 6 cases had multiple carcinomas in the unilateral renal pelvis and ureter and simultaneously involved urinary bladder, 3 cases had the multiple carcinomas in the unilateral renal pelvis and ureter, and 1 case had the multiple carcinomas in the lower and middle ureter and involved urinary bladder. CT images clearly presented the thickened irregular renipelvic and ureteric wall with stenosis and/or mass in the renipelvic and ureteric cavity. The urinary bladders involved by carcinoma were depicted as thickened irregular wall of urinary bladder or the mass in the wall of urinary bladder. The images of curved reconstruction clearly showed the extention of the multiple carcinomas and the changes of the urinary tract involved by the multiple carcinomas. Enlarged retroabdominal lymph nodes were detected in 3 cases simultaneously, and 2 of them were proved metastasis, the imaging findings were absolutely identical to that of the operation and pathological examination. Conclusion Sixteen slice spiral CT can clearly and accurately depict the location and extention of multiple carcinomas in the unilateral upper urinary system.

Purpose To investigate the CT and CTA findings of intracranial hemanigoperiocytoma. Materials and Methods The CT and CTA data of 7 cases of pathologically confirmed intracranial hemanigoperiocytoma were retrospectively reviewed. Results All the 7 cases were extra-axial and supratentorial location. Six were lobulated and 1 were oval in shape. Three were iso-density to the parenchyma and 4 were inhomogeneous with clear margins. Five had perifocal edema. On contrast scan, all showed homogeneous or inhomogeneous enhancement. Five had dilated tortuous vessels and 4 were identified as feeding artery inside or around the tumors. Conclusion The CT findings of intracranial hemanigoperiocytoma are similar to meningioma but CTA is helpful for the differential diagnosis.