ABSTRACT
Objective To make correct diagnosis for Rathke cleft cyst(RCC)and cystic pituitary adenomas(CPA)through retrospective analysis of characteristics of MRI.Methods RCC (n=30)and CPA (n=30)confirmed by surgery and pathology were analyzed retrospectively.Following characteristics of lesions were observed:morphology,size,location,range,T1WI signal intensity and patterns of enhancement,presence of intracystic fluid level,septum,nodule,hypointense rim on T2WI and change of the pituitary stalk.The independent sample t-test and χ2 test were used respectively to analyze differences between two groups of continuous variables and categorical variables.Results Most of RCC were oval,less than 2 cm3,under the optic chiasm and within the bilateral cavernous sinus,various for signal intensity,without or with thin-walled contrast enhancement.Intracystic nodule accounted for 40% of cases and there were double cystic nodules in 1 case.Obvious contrast enhancement of intracystic nodule was found in 1 case.Pituitary stalk was in center.Most of CPA were snowman shaped,bigger than 2 cm3,off middle line location,with compression of the optic chiasm and sellar base,had thick-walled contrast enhancement,with intracystic fluid level and septum,had hypointense rim on T2WI.The pituitary stalk was shifted.Conclusion The MRI findings of RCC and CPA are significant differences in the shape,size,intracapsular structure,enhanced performance and changes of surrounding structure.
ABSTRACT
The purpose of this study was to evaluate relative regional blood volume (rCBV) in meningioma and compare the utility of reconstruction using both gradient-echo sequence and echo-planar-imaging (EPI) sequence. Eighteen patients with meningiomas were studied on a Siemens 1.5-T scanner. During the gradient-echo sequence (n=12) and EPI sequence (n=6), a bolus (0.2 mmol/kg) of Gd-DTPA was injected mechanically with a flow rate of 5 ml/second. Image processing of dynamic data was performed on a pixel-by-pixel basis. The ratio of tumor rCBV/gray matter rCBV was 3.01 +/- 1.18 (3.07 +/- 1.39 in gradient sequence and 2.84 +/- 0.94 in EPI sequence). The ratio of gray matter/white matter as the reference tissue had a mean of 2.79 +/- 0.76 using the FLASH sequence, and a mean of 3.04 +/- 1.31 using EPI. These differences were not statistically signifcant (P>0.5, t-test). According to the ratio of tumor rCBV/gray matter rCBV, a mean value, 14.5 ml/100 g, of rCBV in meningiomas was calculated. Compared with gray matter, increased inhomogeneous rCBV was observed in meningioma. Based on the two different sequences, no bias can be observed in our rCBV reconstruction.
Subject(s)
Adult , Aged , Aged, 80 and over , Female , Humans , Male , Middle Aged , Blood Flow Velocity , Echo-Planar Imaging , Gadolinium DTPA , Magnetic Resonance Imaging , Methods , Meningeal Neoplasms , Meningioma , Regional Blood Flow , Sensitivity and SpecificityABSTRACT
Objective To evaluate the effect of simpler and chemotherapeutic renal artery embolizations in the treatment of renal carcinoma preoperatively Methods 19 patients including simpler renal artery embolizaiton group( n =8) and chemotherapeutic renal artery embolization group( n =11) were retrospectively studied. The surgical procedures were recorded and pathology sections were observed for all the patients. Results All the preoperative embolization were achieved successfully. We found vessels obliteration of the renal carcinoma in the operation. In pathology, the tumor had clear border with the necrosis. Conclusions Preoperative renal artery embolization could decrease the risk in operation, and had positive effects on the prognosis of these patients.
ABSTRACT
Objective To study the diagnostic evaluation of spiral CT for acute pulmonary embolism(PE).Methods 24 patients with PE were scanned with SCT(Philips AVEL.)pre-and post-injection of 100 ml contrast medium(Ultravist or Omnipaque 300 mgI/ml)from elbow vein.Enhanced CT scans were started after injection of 15 and 30 seconds respecting.Results The indirect signs on plain CT image were:lung-making sparse in 12 cases;lesion of pulmonary infarction in 11 cases;pulmonary hypertension signs in 3 cases;pleural thickening in 4 cases;pleural effusions in 8 cases.The direct signs on enhanced CT images were:Intraluminal filling defect (mural filling defect in 32 vessels;partial filling defect in 30 vessels;total occlusion in 92 vessels and central filling defect that was railway-track sign in 15 vessels)and smaller caliber of pulmonary artery in 14 vessels.Conclusion Enhanced pulmonary SCT angiography is the safe,quick and effective imagilogic examination for acute PE.