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1.
Chinese Journal of Postgraduates of Medicine ; (36): 140-145, 2020.
Artigo em Chinês | WPRIM | ID: wpr-865459

RESUMO

Objective To evaluate the value of MRI-T2WI texture analysis in the differentiation of atypical medulloblastoma and ependymoma of the fourth ventricle.Methods Preoperative MRI data of 36 cases of fourth ventricle tumor (19 cases of medulloblastoma and 17 cases of ependymoma) confirmed by the Central Theater General Hospital of the Chinese People's Liberation Army were retrospectively analyzed.Manually sketch areas of interest (ROI) were made using texture analysis software to get histogram parameters,including mean,median,standard deviation,skewness,kurtosis,maximum,minimum,heterogeneity,entropy,the 5th percentile (T2WI5th),the 10th percentile (T2WI10th),the 25th percentile (T2WI25th),the 50th percentile (T2WI50th),the 75th percentile(T2WI75th),the 95th percentile (T2WI95th).Independent sample t test or mann-whitney U test was used for statistical analysis of each parameter value between the two groups.Logistic regression analysis was used to perform multiparameter joint analysis on meaningful parameters.The area under the curve (AUC) was obtained by using the subject operating characteristic (ROC) curve to determine the threshold and diagnostic efficacy for distinguishing the two group.Results The mean,median,T2WI5th,T2W10th,T2WI25th,T2WI50th,T2WI75th values of the medulloblastoma group were smaller than those of the ependymoma group,and difference was statistically significant (P < 0.05).The T2WI5th had the best diagnostic performance.When the critical value was 1 343,the diagnostic specificity was 75.0% and the sensitivity was 92.9%.Logistic regression was used to predict the joint analysis of probability parameters.T2WI15th+T2WI10th had the best performance,and AUC was 0.928.When the critical value was 0.75,the diagnostic specificity was 75.0% and the sensitivity was 100.0%.Conclusions MRI-T2WI texture analysis can provide quantitative information for preoperative diagnosis of atypical medulloblastoma and ependymoma and improve the accuracy of preoperative diagnosis,which has obvious clinical value.

2.
Chinese Journal of Postgraduates of Medicine ; (36): 140-145, 2020.
Artigo em Chinês | WPRIM | ID: wpr-799624

RESUMO

Objective@#To evaluate the value of MRI-T2WI texture analysis in the differentiation of atypical medulloblastoma and ependymoma of the fourth ventricle.@*Methods@#Preoperative MRI data of 36 cases of fourth ventricle tumor (19 cases of medulloblastoma and 17 cases of ependymoma) confirmed by the Central Theater General Hospital of the Chinese People′s Liberation Army were retrospectively analyzed. Manually sketch areas of interest (ROI) were made using texture analysis software to get histogram parameters, including mean, median, standard deviation, skewness, kurtosis, maximum, minimum, heterogeneity, entropy, the 5th percentile (T2WI5th), the 10th percentile (T2WI10th), the 25th percentile (T2WI25th), the 50th percentile (T2WI50th), the 75th percentile(T2WI75th), the 95th percentile(T2WI95th). Independent sample t test or mann-whitney U test was used for statistical analysis of each parameter value between the two groups. Logistic regression analysis was used to perform multiparameter joint analysis on meaningful parameters. The area under the curve (AUC) was obtained by using the subject operating characteristic (ROC) curve to determine the threshold and diagnostic efficacy for distinguishing the two group.@*Results@#The mean, median, T2WI5th, T2WI10th, T2WI25th, T2WI50th, T2WI75th values of the medulloblastoma group were smaller than those of the ependymoma group, and difference was statistically significant (P<0.05). The T2WI5th had the best diagnostic performance. When the critical value was 1 343, the diagnostic specificity was 75.0% and the sensitivity was 92.9%. Logistic regression was used to predict the joint analysis of probability parameters. T2WI5th+T2WI10th had the best performance, and AUC was 0.928. When the critical value was 0.75, the diagnostic specificity was 75.0% and the sensitivity was 100.0%.@*Conclusions@#MRI-T2WI texture analysis can provide quantitative information for preoperative diagnosis of atypical medulloblastoma and ependymoma and improve the accuracy of preoperative diagnosis, which has obvious clinical value.

3.
Journal of Practical Radiology ; (12): 523-526, 2019.
Artigo em Chinês | WPRIM | ID: wpr-752386

RESUMO

Objective ToinvestigatethevalueofimagetextureanalysisbasedonconventionalMRimagesinthedifferentialdiagnosisof intracranialsolitaryfibroustumor/hemangiopericytoma(SFT/HPC)andvascularmeningiomas.Methods 12casesofSFT/HPCand 16casesofvascularmeningiomaconfirmedbypathologywerecollected.Variousdiscriminantanalysismethodsandimagetextureanalysis techniqueswereappliedtopre-operativeroutineMRIimagesofthebrain,andthebesttextureparameterswereselectedtoclassify cases,includinglineardiscriminantanalysis(LDA),nonlineardiscriminantanalysis(NDA),principalcomponentanalysis(PCA)and rawdataanalysis(RDA).Finally,thebestclassificationsequencetextureparameterswerechosenforstatisticalanalysis.Results The enhancedT1WIwasthebestclassificationsequence.ThePOE+ACC methodhadthelowestmisclassificationrate.Theabsolutegradient skewness,theautocorrelationofthecooccurrencematrix,andthevarianceofthehistograminthetexturefeaturesoftheSFT/HPC andvascularmeningiomasweredifferent(P<0.05).Conclusion ThatbasedontheconventionalMRimagetextureanalysiscanprovidemore quantitativeinformation,anew methodandideafortheidentificationofintracranialSFT/HPCandvascularmeningioma.

4.
Chinese Journal of Postgraduates of Medicine ; (36): 224-228, 2016.
Artigo em Chinês | WPRIM | ID: wpr-487489

RESUMO

Objective To evaluate the imaging performance and characteristics of peripheral primitive neuroectodermal tumors (pPNET), in order to raise awareness of the disease and the diagnostic accuracy. Methods Thirteen patients with pPNET who confirmed by puncture or pathology were enrolled in this study. The CT and MRI features were retrospectively analyzed. Four patients received simple routine CT examination, and 9 patients had MRI examination based on X-ray, CT examination. Results The part of body involved was more widely.Two patients occurred in the sinuses, 1 patient in the chest wall, 1 patient in the lung, and 3 patients in the abdominal and pelvic(1 patient involved the pelvic floor through the pelvic wall lesions to basins), 1 patient in the spine, and 5 patients located in the extremities. The characteristics of pPNET by CT and MRI in soft tissue of 8 patients showed single large soft tissue mass, and the biggest was 11.2 cm × 10.6 cm. In bonds and joints of 5 patients, CT and MRI showed wide range of soft tissue mass, mixed internal signal/density with obviously uneven enhancement, significant bone destruction and dissolvable osseous changes, and no obvious tumor bone and calcification. Conclusions Each site has its relative imaging characteristics of pPNET. CT and MRI can show lesions involving the scope, internal structure, with or without adjacent tissue invasion and metastasis, and provide guidance for clinical treatment and selecting treatment regimen. But in the end, it depends on the diagnosis of pathological and immunohistochemical examination.

5.
Chinese Journal of Pancreatology ; (6): 107-110, 2012.
Artigo em Chinês | WPRIM | ID: wpr-418269

RESUMO

ObjectiveTo study the water/fat ratio of patients with pancreatic ductal adenocarcinoma (PDAC) and mass-forming focal chronic pancreatitis (MFP),and to provided guide for the clinicians.MethodsThirteen patients with PDAC,8 patients with MFP and 20 healthy volunteers were scanned by GE 3.0T MR IDEAL sequence.The signal strength of outcome images was measured; the water/fat ratio analysis was performed.Two kinds of formula were applied,the first was WF1 =SW/SF,the second was WF2 =( SIP + SOP) / ( SIP - SOP).SW was the signal strength of water,SF was the signal strength of fat,and SIP was the signal strength of in-phase,while SOP was the signal strength of opposite phase.ResultsBy using the WF1 formula,the water/fat ratio of normal pancreas,PDAC,MFP was 7.97 ±0.95,9.94 ±1.19,5.08 ±0.49,respectively.By using the WF2 formula,the water/fat ratio of normal pancreas,PDAC,MFP was 11.51 ± 1.62,13.87 ±1.84,5.73 ±0.65,respectively.The difference among the three groups was statistically significant (P < 0.05 ) under the same formula.The value of WF2 was higher than that of WF1,the difference in PDAC groups was also statistically significant ( P <0.05 ).ConclusionsThe water/fat ratio of pancreas among PDAC,MFP and normal pancreas is different.PDAC has the highest water/fat ratio,followed by the normal pancreas; MFP has the lowest ratio.

6.
Chinese Journal of Pancreatology ; (6): 339-342, 2011.
Artigo em Chinês | WPRIM | ID: wpr-422344

RESUMO

Objective To observe the metabolic characteristics of an experimental model of chronic pancreatitis,and to investigate its role in the grading of chronic pancreatitis.Methods Thirty-six Wistar rats were injected with dibutyltin chloride (DBTC) solution (8mg/kg) via the tail vein to establish the experimental model of chronic pancreatitis.The 36 rats were divided into 6 groups with 6 rats in each group.On0,7,14,21,28,35 days after modeling,rats was sacrificed and pancreatic tissue of the rats was harvested,and a small part was used for pathologic study,the majority part was kept at-80℃ under liquid nitrogen freezing.Metabolites of pancreatic tissue were determined by high-resolution magic angle spinning nuclear magnetic resonance spectroscopic (HR-MAS NMRS).On the basis of the abnormal structure,tubular complexes,gland atrophy,fibrosis,edema and inflammatory cell infiltration,chronic pancreatitis was graded.Results Pathologic study showed the severity of chronic pancreatitis gradually increased with time after modeling.The 7th,14th day after modeling,the pancreatic change was mild chronic pancreatitis; the 21st,28th,35th day,the pancreatic change was changed into severe chronic pancreatitis.Principal component analysis of HR-MAS NMRS showed that the betaine (Bet) and choline ( Cho)-contained components were significantly increased in severe chronic pancreatitis; while aspartate (Asp),lactate (Lac),isoleucine/leucine/valine (I/L/V) and fatty acid (FA) were significantly reduced when compared with those in mild chronic pancreatitis and normal pancreatic tissue.There was no significant difference in the amount of metabolic characteristics between mild chronic pancreatitis and normal pancreatic tissue.Conclusions HRMAS NMRS was helpful in distinguishing the severe chronic pancreatitis from mild chronic pancreatitis.

7.
Chinese Journal of Pancreatology ; (6): 243-246, 2011.
Artigo em Chinês | WPRIM | ID: wpr-421269

RESUMO

Objective To investigate the feasibility of pancreatic DWI at a 3T MR imager and its value for the qualitative diagnosis of pancreatic tumors. Methods For 20 normal healthy volunteers and 47 patients with pancreatic tumors [21 pancreatic carcinoma (PC), 7 mass-forming chronic pancreatitis (MFCP)and 19 cystic lesions), routine pancreatic MRI and pancreatic DWI using b values (500 and 1000 mm2/s)were obtained, the DWI signal intensity (SI) and apparent diffusion coefficient (ADC) value of pancreatic lesions and adjacent tissue was measured. Results In the b = 500 and 1000 mm2/s DWI images, there was no significant difference in ADC value between different parts of normal pancreas. But PC and MFCP were shown as hyperintensity mass, in addition, the related SI1000 of PC at b = 1000 mm2/s DWI was significantly higher than that of MFCP (1.238 +0.448 vs. 0.371 +0.293, P<0. 01). Compared with normal pancreas,beth PC and MFCP presented as decreased ADC500 and ADC1000 value. The ADC1000 of PC was significantly lower than that of MFCP [ ( 1. 087 + 0. 175 ) mm2/s vs. ( 1. 279 ± 0.213 ) mm2/s]. Pancreatic cystic lesions were shown as hyperintensity in DWI at b = 500 mm2/s, but were depicted as iso-intense signal or low-signal lesions in DWI using b = 1000 mm2/s. Both ADC500 and ADC1000 of pancreatic cystic lesions were higher than that of normal pancreas. Conclusions 3T-MR DWI is helpful to differentiate pancreatic lesions. High b value DWI is more valuable for the qualitative diagnosis of pancreatic mass.

8.
Journal of Practical Radiology ; (12): 457-461, 2010.
Artigo em Chinês | WPRIM | ID: wpr-402639

RESUMO

Objective To study the characteristics of MR imaging and proton MR spectrscopy(~1H MRS)of stroke-like lesions in MELAS.Methods Clinical,MR imaging and proton spectroscopic findings of stroke-like lesions in 7 patients with confirmed MELAS were analyzed retrospectively.Results A total of 12 MR investigations had been performed in 7 patients.Stroke-like lesions showed by MR imaging included superacute in 12,acute in 12,subacute in 10 and chronic stage in 6.Early stroke-like lesions were demonstrated as focal edematous foci mainly involved cortex/subcotical areas of occipital,temporal and parietal lobes.At MR diffusion imaging,stroke-like lesions in the superacute(<3 days)stage were showed as well-circumscribed lesions with high signal intensities for cytotoxic edema.During the acute(4~7 days),sub-acute(2~4 weeks)and chronic(>4 weeks)stages,the lesions gradually expanded,and became blur,and presented with vasogenic edema mainly.Proton spectroscopy showed a prominently elevated lactate,varied decrease of NAA concentration and other brain motabolites in the stroke-like lesions early after onset,and depicted gradual decrease of lactate level and partial recovery of NAA concentration subsequently.Conclusion Stroke-like lesions in MELAS mainly involve the cerebral cortex and subcortical areas,in which cytotoxic edema appears early but for a short period.In ~1H MRS,the lesions are characterized by a double lactate peak with decrease of NAA concentration.

9.
Journal of Medical Research ; (12)2006.
Artigo em Chinês | WPRIM | ID: wpr-564195

RESUMO

Objective To investigate the MSCT(multi-slice computed tomography) manifestation of different kinds of malignant tumor in Renal Sinus.Methods MSCT data of 31 patients with diferent kinds of malignent tumor in Renal Sinus were analyzed retrospectively.Results In our series,15 cases were renal pelvic carcinoma,and central mass in renal sinus with light or middle ehancement were revealed in their MSCT investigation,as well as pelvic filling defect and hydronephrosis to some extent were found in secretory phase of enhanced MSCT.10 cases were renal cell carcinoma with renal sinus invasion,and their MSCT muti-planar reconstruction showed the mass mainly located in renal parenchymal,with dramatical and heterogenous CT enhancement mostly,besides local oppression & latral destruction of pelvic wall were caused by renal pelvic invasion.2 cases leiomyosaocoma in renal sinus were big and had a sharp edge,after adminisration they demonstrated dramatical and heterogenous CT enhancement.3 cases were lymphnode metastasis located in renal sinus or renal gate,appeared as nodular lesion with CT enhancement,and hydronephrosis could be exsisted if renal pelvic were obstructed.1 case were retroperitoneal lymphoma,MSCT muti-planar recon-struction revealed a large retroperitoneal mass derectly invaded into renal sinus,with light or middle homogenous ehancement.Conclusion MSCT has advantages of high speed scan,excellent discrimination,and aplenty post-process technique,and is of diagonotic value to malignant tumor in renal sinus.

10.
Chinese Medical Equipment Journal ; (6)2003.
Artigo em Chinês | WPRIM | ID: wpr-592757

RESUMO

Objective To discuss the clinical value of Mutislice CT angiography (MSCTA)in cervical vascular diseases. Methods 60 patients highly suspected suffering cervical vascular diseases,were implemented 16-slices spiral CT angiography of cervical vascular,and blood vessel reconstruction and analysis were done subsequently. Results 43 cases with cervical vascular abnormality were presented in the 60 patients,who were implemented MSCTA. Positive ratio was 71.7%. 171 pieces vessel stenosis were detected among 240 pieces carotid artery and vertebra artery, and 4 cases carotid artery aneurysm and 1 case AVM were found also. Conclusion MSCTA is a convenient and shortcut modality to inspect cervical vascular diseases, and the blood vessel can be observed 3-dimensionally and in any direction in high quality reconstruction images.

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