ABSTRACT
Objective To study the possibility of microvascular permeability (PS) value derived from perfusion CT (PCT) in predicting hemorrhagic transformation (HT) in acute cerebral infarction in elderly patients.Methods 52 consecutive patients with middle cerebral artery acute ischemic stroke who received thrombolytic therapy were divided into HT group and control group,and patients in HT group were further divided into hemorrhagic infarction (HI) group and parenchymal hematoma (PH) group.PCT data and Alberta stroke program early CT scores (ASPECTS) from CT angiography source images (CTA-SI) achieved within 6 hours after symptom onset of each group was retrospectively analyzed and statistically processed.Results In 52 patients,there were 22 cases developed HT,14 cases with HI,8 cases with PH.Cerebral blood flow (CBF) and cerebral blood volume (CBV) values were decreased and permeability surface area product (PS) was increased in ipsilateral in HT group and control group as compared with the contralateral (all P＜0.05).PS value in ipsilateral was significantly higher in HT group than in control group (P＜0.01),but CBF and CBV values in affected side showed no significant difference between the HT group and control group.The area under the receiver operator characteristic (ROC) curve of PS Az value was 0.968.When PS ≥5.77 ml · min-1 · 100 g-1,the sensitivity and specificity of predicting HT were 95.5％ and 86.7％ respectively.The ASPECTS was lower in HT group than in the control group (P＜0.01),and ASPECTS was higher in HI group than in PH group (P＜0.01).The differences in PCT results in affected side between the HI group and PH group was not significant.Conclusions The significantly increased PS value can be a reference in predicting HT risk and guiding thrombolytic therapy.
ABSTRACT
Objective To investigate the relationship between the tube voltage and radiation dose as well as image quality in adult upper airway digital radiography (DR).Methods We used CDRAD2.0 contrast details phantom and PMMA to simulate adult upper airway. With different tube voltages,the phantom was exposed using automatic exposure control system (AEC).The entrance surface dose( ESD),dose area product(DAP) and mAs in every exposures were recorded.The image quality factors(IQF) of all images were calculated. Results With tube voltage increasing,ESD,DAP,mAs decreased and IQF value enhanced.There were statistically significance ( F =45.15,26.41,29.26,56.53,P ＜ 0.05 ).ESD,DAP,mAs significantly increased with tube voltage less than 75 kV,began to decrease when tube voltage more than 75 kV,tended to be on the balance in 75 -80 kV.At the same time,the fluctuation of IQF value was no statistical difference in 50 - 75 kV of tube voltage,but was statistical significance in 75 -90 kV( F =11.35,P ＜0.05 ).So,the image quality of adult upper airway with different tube voltage had no significant difference.Conclusions The appropriate tube voltage was 75 kV to 80 kV in the upper airway DR.The IQF value can be provided as the clinical evaluation index of image quality.
ABSTRACT
ObjectiveTo evaluate the clinical effect of MSCT measurements in the pre- and postoperational osteal posterior cranial fossa for the adult patients of basilar invagination.Methods We reviewed the images of a cohort of 31 adult patients with basilar invagination,which were treated by surgical operation.According to the presence of atlantoaxial dislocation,the patients were divided into groups A and B.The basion-dens interval (BDI),atlanto-dental interval (ADI),space available of the spinal cord ( SAC),clivus-canal angle( CCA),Highly index( HI),and Chamberlian line(CBL) of the posterior cranial fossa were obtained in all the patients.Independent-sample Student's t test was used to compare the differences between groups A and groups B.Spearman correlations were analyzed between CT measurement data and effects of operations.ResultsIn Group A,the BDI,ADI,SAC,CCA,HI,CBL before and after surgery were 12.6 mm,8.3 mm,4.5 mm,3.3 mm;18.2 mm,20.8 mm,138.3°,150.4°,28.7 mm,43.4 mm,6.3 mm,3.3 mm respectively.There were significant differences ( t = 5.603,2.323,3.124,5.531,4.278 and 2.375,respectively,P ＜0.05 ).Preoperative JOA score in groups A was 10 points,and was 14 points after surgery.There was significant difference between the JOA scores before and after surgery ( t = 3.526,P ＜ 0.05 ).There were 7 effective cases and 4 stable cases after surgery in group A.Before and after surgery,JOA score and BDI,ADI,SAC,CCA,HI,CBL were significantly correlated( r = -0.667,- 0.673 ; - 0.571,- 0.619 ; 0.642,0.513 ; 0.525,0.558 ; 0.587,0.511 ; - 0.532,- 0.596,respectively,P＜0.05).The SAC,CCA,and CBL before and after surgery in group B were 18.3 mm,19.6 mm,146.8°,150.2°,2.7 mm,1.8 mm.The difference was statistically significant after operation ( t = 5.359,4.126,0.769,P ＜0.05).The BDI,ADI,and HI before and after surgery in group B were 7.2 mm,6.6 mm,2.4 mm,2.1 mm,39.3 mm,41.5 mm.And there were no significant differences (t = 1.482,2.374,0.153,P＞0.05).The preoperative JOA score in groups B was 11 points,and the postoperative score was 16 points.JOA scores before and after surgery were significantly different (t =2.874,P ＜0.05).There were 14 effective cases and 6 stable cases after operation in group B.The JOA score before and after surgery and BDI,ADI,and HI had no correlation (r =0.341,0.387;0.154,0.182; 0.192,0.167,P ＞0.05),and CBL,SAC and CCA were correlated (r = -0.756,-0.728;0.651,0.672; 0.726,0.695,P ＜0.05).ConclusionMSCT measurements for basilar invagination before and after surgery are helpful for understanding changes of osteal posterior fossa anatomy and comprehensive evaluation of surgical treatment.
ABSTRACT
Objective To assess the clinical value of MSCT in diagnosing the overcrowding of osteal posterior cranial fossa (PCF) in adults.Methods MSCT images of a cohort of 52 adult patients with foramen magnum osteal malformation confirmed by surgery (diseased group), and 100 healthy adults (control group) were retrospectively reviewed.Images post-processing techniques included multi-planer reformation (MPR) and volume rendering (VR).The posterior cranial fossa volume (PCFV), posterior cranial fossa height (PCFH), clivus length (CL), clivus gradient (CG), supraocciput length (SL), and anteroposterior diameter of the foramen magnum (FMD) were measured on sagittal images in 52 patients and 100 normal adults.Independent-sample student's t test was used to compare the differences between patients and normal adults.Results The results of PCFV, PCFH, CL, SL,FMD and CG, male of control group were (168.2 ±12.3) cm~3, (38.2 ±1.2), (47.1 ±2.8), (41.1 ±1.8), (36.6 ±4.9) mm, (51.5±3.6)°, female of control group were (157.5 ±10.2) cm~3, (36.5 ±1.4), (46.2 ±2.2), (39.7 ±1.3), (35.2 ±3.8), (49.6±3.1)° ;diseased group were (128.7 ±11.7) cm~3, (30.6 ±1.9), (36.2 ±1.4), (37.3 ±0.9), (33.9 ±3.5)mm, (44.5 ±2.8)° .There was significant sex difference in PCFV, PCFH, CL, SL and CG in control group (t =4.70, 6.44, 4.84, 4.43 and 2.81 respectively, P<0.01), but FMD was not significant(t=1.97,P>0.05); the results of PCFV, PCFH, CL, CG and SL were significant different between diseased group and male of control group (t=16.62, 24.04, 25.01, 14.17 and 10.99 respectively,P<0.01) ; the results of PCFV, PCFH, CL, CG and SL were significant different between diseased group and female of control group (t=13.23, 17.80, 27.50, 11.67 and 8.73 respectively,P<0.01) ;but there were no significant differences of FMD between diseased group and control group, both male and female (t=2.96,2.07, P> 0.05).Conclusions The overcrowding of PCF can be accurately measured by MCST.As a routine preoperative examination, MSCT is helpful in the therapeutic selection and the anatomic and pathologic study of PCF.
ABSTRACT
Objective To study the correlation among pathological,clinical and the imaging features(CT and MRI) of the Rathke cleft cysts.Methods CT,MRI and clinical findings of Rathke cleft cysts in 43 patients confirmed by operation and pathology were retrospectively studied.Results 27 cysts located at intrasella and suprasella and 16 cysts entirely located at intrasella.Cysts were round or oval in shape with definite borders.The size of 30 cysts exceed 10mm in diameter.On CT scans reviewed,the cysts were low density in 9 cases,hyper-density in 9 cases and isodensity or mixed density in 8 cases.The cyst's wall with calcification was seen in one.On postcontrast CT scans,6 cases showed circular and peripheral cyst's wall enhancement and others were no enhancement.On MR imaging,the lesions were low or isodense on T1WI and hyper-intensity on T2WI in 18 cases,both were high signal intensity on T1WI and T2WI in 6 cases,high signal intensity on T1WI and mixed signal intensity on T2WI in 4 cases.An intracystic nodule having high signal intensity on T1WI,and low or mixed signal intensity on T2WI was observed in 4 cases.On contrast-enhanced MR imaging,enhancement of the cyst's wall was shown in 9 cases.During surgery,the lesions were noted to have a cyst of semisolid consistency,and cystic contents were described from CSF-like clear fluid in 10 cases,jellied-like brown mucoid fluid in 15 cases,caseous-like mucoid fluid in 12 cases,machine oil-like mucoid fluid in 6 cases.At histopathology,a part of cystic fluid included cholesterol crystal and necrotic debris.Cholesterol clefts and hemosiderin pigment,and granuloma were shown by staining with HE in 11 cases.The PAS staining was positive in 16 cases,cystic fluid contained partial mucopolysaccharides and protein.Conclusion Typical Rathke cysts can be dignosised in the preoperative,the findings of CT and MRI are not specific in atypical cysts.The imaging features were different with the fluid component of Rathke cleft cysts..
ABSTRACT
Objective To study CT and MRI features of intracranial chondrosarcomas. Methods CT and MRI of 3 cases with intracranial chondros arcomas proved by pathology were retrospectively analyzed.Results CT scans showed the tumors were lobular mass, per itumoral edema were not serious, intratumorous calcification and bone invasion w ere seen in 2 cases.MRI showed that tumor had low to intermediate signal intensi ty or hypointensity on T 1WI, high signal intensity on T 2WI. On contrast enha nced MRI,the center of lesions which was low signal intensity on T 2WI was no e nhancement, but there was observable enhancement at periphery of tumors.Conclusion Intracranical chondrosarcomas are often orgina ted from synchondrosis of the skull base,the lesions are often associated with c alcification, and bone invasion, the accurate dignosis should depend on microsco pic examination and immunohistochemical staining.
ABSTRACT
Objective:To analyse the imaging featrues of intractranial tuberculoma and improve the diagnostic accuracy.Methods:31 patients with clinical characteritics and pathological proved intracranial tuberculomas were studied retrospectively.Results:"egg-shell"calcification were the feature of giant calcified and ossified tuberculoma.CT scaning were single and multiple nodular lesion.In the contrast enhancing CT scaning,plate shaped or ring form shadows were shown.MRI were provided hypointense on T1WI and hyperintense on T2WI.The rim homogeneous enhancement were showd in the Gd-DTPA.Conclusion:The diagnosis of typical intracranial tuberculomas can be made.After antituberculosis chemotherapy,CT and MRI can help made differsntial diagnosis.Operative indications should be select strictly.