Objective To explore the clinical value of whole-brain CT perfusion imaging with 320-detector row CT in early acute cerebral infarction.Methods The CTP parameters(CBF,CBV,MTT,TTP)and its pseudo color map of 25 patients with early acute cerebral infarction were retrospectively analysed and compared between infarction area,ischemic penumbra (IP)and the con-tralateral normal region.Results The abnormal perfusion area were found on CTP in 25 patients with early acute cerebral infarction. CTP showed cerebral blood flow (CBF)and cerebral blood volume (CBV)decreased significantly,mean transit time (MTT)short-ened significantly,time to peak (TTP)was significantly longer than those of the contralateral normal region in 7 cases of acute cere-bral infarct core.18 cases of IP lesions showed CBF decreased slightly,CBV increased slightly or maintain normal,MTT and TTP extension compared with contralateral.CBF,CBV,MTT,TTP values had significantly differences between infarct region and the contralateral corresponding normal region,between the infarct core area and IP of acute cerebral infarction (P <0.01).CBF,MTT, TTP values had statistically significant(P <0.05),and CBV values was not statistically significant (P >0.05)between IP region and the contralateral corresponding normal region,but showed a downward trend in blood flow.Parameter color maps of CTP could di-rectly,clearly and sensitively show abnormal changes region about cerebral blood flow.In particular,MTT and TTP maps shows ab-normal region clearer and sensitively.Follow-up 18 cases of IP,active lesions deduced in 6 cases,the lesions disappeared in 5 pa-tients (CT/ MRI showed no abnormal,and the clinical symptoms disappeared)after thrombolytic therapy,7 cases of MRI and CT scans confirmed infarction stove.Conclusion Whole-brain CTP with 320-detector row CT can early show the acute cerebral infarc-tion and its ischemic penumbra,it has significant important clinical value for early acute cerebral infarction.

Objective To explore the X-ray ,CT and MR manifestations of spinal giant cell tumor(GCT) for improving the diag-nosis level of this rare disease .Methods The X-ray ,CT and MR data in 16 cases of spinal GCT were retrospectively analyzed on the location ,size ,morphology ,margin ,CT density/MR signal intensity and enhancement pattern .Results 4 cases located in cervical vertebra ,8 cases in thoracic vertebra and 4 cases in lumbar vertebra ;in which ,6 cases only involved in vertebral body and other 10 cases involved in vertebral body and and appendix .The lesion affected two neighboring vertebrae in 8 cases ,and affected only one vertebra in the remaining 8 cases .16 cases were protruded into the spinal canals and oppressed the spinal cord .The prominent X-ray and CT images showed eccentric growth ,osteolytic and swelling bone destruction .MR showed isointensity or slight hypointensity on T1WI ,and isointensity or slight hyperintensity on T2WI .After intensified scanning ,the solid portion showed marked inhomoge-neous enhancement .Conclusion Spinal GCT has certain imaging characteristics .CT and MR examination could accurately display the extent of lesion and tumor involvement ,which provides more accurate image information for formulating the strategy of clinical therapy .

Objective To explore the feasibility of quantitative hemodynamics measurement of inferior vena cava (IVC) in healthy volunteers with phase-contrast sequence on 3.0 T MR system (3.0 T PC-MRI),and to evaluate the relationship between IVC lumen area,blood flow,and velocity.Methods Fifty healthy adult volunteers prospective underwent IVC PC-MRI at 3.0 T MR system.All volunteers were from our hospital for the routine chest or abdomen examinations,no heart disease and lung disease always,heart rate,blood pressure,electrocardiogram was in normal range,no abnormalities were found in clinical and abdominal imaging examinations,and IVC disease was excluded by ultrasonic examination.The area (A),mean velocity (MV),mean flux (MF),regurgitant fraction (RF) and time-flow curve of upper and middle segments of IVC during one cardiac cycle were observed.Independent samples t test was used to compare IVC lumen area and blood flow,velocity between different genders,different age groups (18 to 30 years old group,more than 30 years old group) and different phase velocity encoding value of IVC middle segment,one-way ANOVA was used to compare different phase velocity encoding value of IVC upper segment [(60,80,100)cm/s].Pearson correlation coefficient and regression equation were used to evaluate the relationships between area,blood flow,and velocity.Results Among 50 patients with successful completion of the examination,significant difference was found in A,MV,MF and RF between the different IVC segments.MF of the IVC middle segment were (37.94 ± 7.32) and (33.68 ± 6.65) ml/s in male (n =24) and female (n =26),respectively ; significant difference was found in different genders (t =2.49,P =0.017).MF of upper segment and middle segments of IVC were (54.89 ± 10.98)and (38.29 ± 7.54)ml/s in 18 to 30 years old group(n =27),while MF of upper segment and the middle of IVC were (44.96 ± 8.49) and (32.65 ± 5.59) ml/s in older than 30 years old group (n =23) with significant difference(t =3.34,2.15,P ＜ 0.01).Peak positive velocity were (55.36 ± 6.30),(61.30 ± 12.42),(62.55 ± 13.09) cnm/s in different phase velocities (60,80 and 100 cm/s),while peak negative velocity (PNV) were (42.37 ± 19.18),(32.79 ± 24.67),(24.61 ± 21.20) cm/s with significant differences (F =4.258,7.794,P ＜ 0.05).The overall image quality was good for quantitative measurement between different phase velocity encoding values of upper segment and the middle IVC (image evaluation are greater than or equal to 3,11 patients were three points,24 patients were four points,15 patients five points).The relation between the PC flow image of IVC and the cardiac cycle was sine wave,the area and the velocity of upper and middle segments of IVC was negative (r =-0.466 and-0.765,P ＜ 0.01),and no linear correlation between the area and the flow of upper and middle segments of IVC (r =0.259,0.046,P ＞ 0.05).There were slight reverse flow during systolic and diastolic cycle.Conclusion The area,flow and velocity of IVC can be rapidly,accurately and noninvasive measured with PC-MRI,and different ages,different genders and different anatomical parts of IVC had obvious hemodynamic differences.

Objective To investigate the diagnostic value of calcification and cystic lesion of CT findings in differentiating pancreatic head ductal carcinoma (PHDA)from mass-forming chronic pancreatitis (MFCP)of the pancreatic head.Methods The clinic data and CT findings of 30 cases with PHDA and 24 cases with MFCP of the pancreatic head,which were confirmed by surgery and pathology were analyzed retrospectively.The images were reviewed independently by two expert radiologists with a double-blind method.An independent sample t test and chi-square test were used to compare the data of imaging findings between two groups.Results ① Calcification was found in 14 cases (58.33%)with MFCP and in 3 cases (10%)with PHDA (P＜0.001).The percentage of patchy,punctate and mixed calcification were 28.57% (n=4),14.29% (n=2)and 57.14% (n=8)in MFCP,0% (n=0),66.67% (n=2)and 33.33% (n=1) in PHDA,respectively.② Necrotic cyst was founded in 7 cases (29.17%)with MFCP and 18 cases (60%)with PHDA(P＜0.05). Pseudocysts were demonstrated in 14 cases (58.33%)with MFCP and in 3 cases (10%)with PHDA (P＜0.001).Honeycombed change with tension within or around the lesion were demonstrated only in patients with MFCP.In addition,normal tissue of the pancreas was found within the lesion in 11 cases (45.83%)of MFCP and none in PHDA,which showed significant difference between two groups.Conclusion Mixed calcification and honeycomb with tension of CT findings are of significant value in differentiating PHDA from MFCP of the pancreatic head.

Objective To evaluate CT vs.MRI in the intrapancreatic and relevant extrapancreatic findings of acute pancreatitis (AP).Methods The clinical data and image findings of 52 AP cases from Jan 2015 to Jun 2017 were analyzed retrospectively.Results CT is comparable to MRI in the diagnostic value of pancreatic enlargement and pancreatic necrosis (all P ＞ 0.05).Compared to CT,MRIwas superior in detecting the peripancreatic exudes,thickening of renal fascia,pleural effusion and abdominal wall edema (all P ＜ 0.01).In favor of MRI,there was significant difference in detection of gallbladder stones and choledocholithiasis,and hepatic swelling,hepatic fatty infiltration.Conclusions Both CT and MRI are significantly helpful to the early precise diagnosis of AP,while MRIis superior in showing etiology,pancreatic hemorrhage and necrosis,extrapancreatic lesions.

Objective:To investigate multimodality imaging characteristics and clinical features of lymphomatosis cerebri (LC) and reasons for misdiagnosis,with the goal of potentially facilitating an early and accurate diagnosis for this often-missed disease.Methods:Clinical data and cerebral multimodality imaging findings from 11 patients with LC proven basing on pathology in the Affiliated Hospital of Guizhou Medical University from November 30, 2011 to December 28, 2020 were retrospectively extracted, analyzed, and reviewed in combination with the literatures.Results:The common presenting symptoms with subacute onset included cognitive decline (8/11), gait disturbance (9/11), and behavioral disturbance (5/11). Test of cerebrospinal fluid showed that the number of cells and the level of protein increased (8/10), the sugar content (2/10) and chloride (4/10) decreased. The imaging manifestations of 11 patients with LC were diffuse lesions of bilateral cerebral white matter in the both deep and lobar lesion distribution, involving the cerebral cortex and subcortical white matter in eight cases (8/11), basal ganglia in seven cases (7/11), thalamus in five cases (5/11), cerebellum in six cases and brain stem in six cases (6/11). All 11 patients showed equal or slightly low-density shadows on CT plain scan and slightly longer T 1WI and T 2WI signals on magnetic resonance imaging. Six cases (6/11) had no obvious enhancement in the early stage, and five cases and six follow-up cases showed heterogenous spots, patches, nodules or clusters of distinct enhancement. Diffusion-weighted imaging showed non restricted diffusion in nine (9/11) cases initially diagnosed, and restricted diffusion in two cases (2/11) and nine follow-up cases, which were hyperintense on diffusion-weighted imaging and hypointense on apparent diffusion coefficient maps. Five patients (5/5) presented a marked decrease in N-acetyl aspartic acid (NAA)/creatine (Cr) and increase in choline (Cho)/Cr on hydrogen proton magnetic resonance spectrum, including an increase in lipid/Cr in three cases. One case (1/3) showed no abnormal increase in lesion metabolism, and two cases (2/3) showed slightly increased uptake on positron emission tomography/CT. Conclusions:Diffuse bilateral cerebral lesions especially in deep and lobar region, without enhancement or with patchy enhancement, marked decrease in NAA/Cr and increase in Cho/Cr and Lip/Cr are suggestive of LC. Misdiagnosis may be mainly due to insufficient understanding and improper brain biopsy.