The lenticulostriate arterys(LSAs)is an important intracranial perforating artery,which is located in the basal ganglia region and the deep nucleus.LSAs lesions will lead to microcirculation disorders in the corresponding blood supply area,which is an important risk factor for stroke.Early effective detection of LSAs lesions to clarify the classification and etiology of stroke,and effective prediction of adverse events has become an urgent problem to be solved.At present,due to the extremely slender diameter and tortuous course of LSAs,the equipment and technology in clinical have not achieved a clear and comprehensive display of the LSAs.With the development of 7.0T ultra-high field MRI,it has become the best method for non-invasive diagnosis of LSAs.This paper aims to summarize the research progress of LSAs and stroke related diseases by 7.0T ultra-high field MRI.

Objective:To observe the size and density of adrenal gland, and the dynamic changes in patients with COVID-19.Methods:Study sample consisted of 67 patients diagnosed as COVID-19 (COVID-19 group) and 70 normal controls. COVID-19 group were divided into two groups: ordinary cases and severe cases. The CT value and thickness of adrenal gland in the control group (uni-temporal) and the COVID-19 group (multi-temporal) were measured, the CT value of adreal/erector spinae were calculated.Results:Compared with the control group, the COVID-19 group had bigger body, medial and lateral branches of bilateral adrenal gland ( P<0.05) . There was no significant difference between the CT value of adrenal/erector spinae for the two groups. Receiver operating characteristic curve analysis showed the thickness of right medial adrenal limb in detecting diffuse adrenal hyperplasia was the best (0.881) . And there was no significant difference in the CT value of adrenal/erector spinae, thickness of bilateral adrenal body, medial and lateral branches in COVID-19 group at different times. Conclusion:The bilateral adrenal glands of COVID-19 patients were slightly swollen, adrenal body, medial and lateral branches were slightly bigger than the normal adrenal glands, but the density was normal, and there were no dynamic changes during the course of the disease.

Objective To compare the image quality between large dose smart tracking technique and low dose test bolus technique for gem spectral CT pulmonary angiography(CTPA).Methods A total of 106 cases with suspected pulmonary embolism were divided into two groups.Group A(54 cases)was carried out with large dose smart tracking technique.Group B(52 cases)was carried out with low dose test bolus technique.We compared the image quality between the two groups.Results There were significant differences in the CT value of the right pulmonary artery and the content of iodine in the lower lobe of the right pulmonary artery of two groups(P<0.01).There was significant difference of image quality between the two groups(P<0.05).The rate of excellent or good image quality in group A was higher than that in group B,and the difference was statistically significant(P<0.05).Conclusion Large dose smart tracking technique can track the artifacts of pulmonary artery imaging with less artifacts and uniform vascular fixation.The image quality of pulmonary artery imaging is better than that of small dose contrast agent.

Purpose To explore an automatic measurement method to replace the manual segmentation of hippocampal volume and brain structure by comparing the relevance and consistency between Freesurfer,as well as voxel based morphometry software (VBM8),and manual measurement of hippocampal volume,respectively.Materials and Methods Totally 67 young subjects (aged 20-40 years) and 75 elderly subjects (aged 60-80 years) were collected separately.After the whole brain MRI scan,the volume of the hippocampus was obtained by manual segmentation,importing to Freesurfer and VBM8 software respectively.Pearson correlation analysis and intraclass correlation coefficient (ICC) were used to statistically analyze the correlation of Freesurfer and VBM with manual measurement.Meanwhile,Bland-Altman scatter plot was used to reflect the consistency.Results Freesurfer and VBM were both highly related with manual measurement.The left and right r values of Freesurfer and VBM were 0.633,0.679 and 0.666,0.703,respectively in the young group,and 0.627,0.765 and 0.663,0.708,respectively in the elderly group;while ICC results showed an obvious difference.The value measured by Freesurfer in young group (ICC=0.377,0.502) was larger than that in the elderly group (ICC=0.307,0.459).However,on the whole,ICC VBM was larger than ICC Freesurfer and right hippocampal volume was larger than left one.The Bland-Altman diagram showed that the consistency of VBM with manual measurement was better than that of Freesurfer.Conclusion Freesurfer can be applied locally on the measurement of hippocampal volume in young subjects.VBM is more accurate than Freesurfer in replacing manual segmentation for measurement of adult hippocampal volume and for volume measurements used in hippocampus related clinical diseases or needed in experiments.

Purpose To investigate the difference of imaging features of tree-in-bud (TIB) sign at CT between stage Ⅰ central lung cancer and bronchial disseminated pulmonary tuberculosis in order to reduce the misdiagnosis rate of central lung cancer.Materials and Methods 32 patients of stage Ⅰ central type lung cancer confirmed pathologically or clinically (lung cancer group) and 47 patients of bronchial disseminated pulmonary tuberculosis confirmed pathologically or clinically (tuberculosis group) underwent chest CT scanning and were found with TIB sign.The imaging data of all the cases were analyzed retrospectively in terms of distribution range,accompanying CT findings of TIB sign,and abnormalities of segmental and (or) larger bronchus proximal to it.Results TIB sign was mainly focal (unilobar) in lung cancer group (96.88％),while it was mainly diffuse (more than one pulmonary lobe) in tuberculosis group (80.85％).The difference was significant (P＜0.01).Accompanying CT findings:① Obstructive bronchial mucoid impaction distal to the TIB was more common in lung cancer group than in tuberculosis group (100％ vs 6.38％,P＜0.01).② Consolidation and/or ground-glass opacities were found both in lung cancer group (34.38％) and in tuberculosis group (48.94％).The difference was not significant (P＞0.05).③ Cavity was less common in lung cancer group than in tuberculosis group (0 vs 38.30％,P＜0.01).④ Nodules with diameter larger than 5 mm were much fewer in lung cancer group than in tuberculosis group (0 vs 76.60％,P＜0.01).TIB sign was found in 33 lobes in lung cancer group,and the abnormity was found in all these lobes (100％);while in tuberculosis group,TIB sign was found in 144 lobes and the abnormity was found in 56 lobes (38.89％).Conclusion TIB sign shows differences between stage Ⅰ central lung cancer and bronchial disseminated pulmonary tuberculosis.The TIB signs such as focal distribution,accompanied by bronchial mucoid impaction and abnormality of segmental or (and) larger bronchus may predict the high possibility of central lung cancer.

Objective To study the occurrence site characteristics of middle cerebral artery aneurysm (MCAA ) in volume CT digital subtraction angiograhy(VCTDSA) .Methods The image characteristics in 72 cases of MCAA from May 2009 to January 2011 were retrospectively analyzed ,according to the running of middle cerebral artery ,the occurrence sites of aneurysm were divided into four categories :M1 segment ,M2 bifurcation ,M2 distal and M3-M5 segment ,the aneurysm number was conducted the statistics and the image characteristics were analyzed ;two neuroradiologists adopted the double-blind method to measure the MCAA angle in bifurcation of M2 segment and compared it with the bifurcation angle in the normal middle cerebral artery ,the difference between them were statistically analyzed .Results (1)M1 segment aneurysms were 7 cases(9 .70% ) ,M2 bifurcation aneurysms were 58 ca-ses(80 .56% ) ,M2 distal aneurysms were 5 cases(6 .94% ) and M3-M5 segment aneurysms were 2 cases(2 .78% ) .(2)The angle in M2 bifurcation of the normal middle cerebral artery was(99 .30 ± 22 .96)° ,M2 bifurcation aneurysm angle was(139 .26 ± 27 .61)° , the difference between them showing statistical significance (P<0 .01) .(3)The difference between left and right of M 2 bifurcation angle in the normal middle cerebral artery had no statistical significance (P>0 .05) .(4)The M2 bifurcation angle in ruptured aneu-rysm was(133 .98 ± 30 .24)° ,which in unruptured aneurysms was(144 .53 ± 21 .81)° ,the difference between them had no statistical significance(P>0 .05) .Conclusion MCAA mainly occurred in M2 bifurcation .There is significant difference in M2 bifurcation an-gle between the aneurysm group and non-aneurysm group ,M2 bifurcation angle is increased ,the probability of aneurysm occurrence is increased .

Case based study emphasizes on the training of students' practical clinical ability. With the development of computer technology, picture archiving and communication system was widely applied, providing bases for case based study. According to the characteristics of radiology, appli-cation of case based study in medical imaging practice teaching was believed to stimulate students' learning interest, improve their analytical ability and thinking capacity, make them combine theory with practice better and develop their clinical thinking ability.

Objective To investigate the relationship between MRI signal type and CT structural characteristics on lumbar hy-perostogeny ,and the possible mechanism of vertebral body remodeling on degenerative lumbar spine .Methods Imaging data of for-ty-five subjects who were referred for both MRI and CT imaging of the lumbar spine from July 2011 to January 2012 were retro-spectively analyzed .Volume Rendering(VR) and Multi-Planar Reformation(MPR) were used to observe structural characteristics of osteophyte .Osteophyte formation ,MRI signal type and CT features of osteophyte were recorded ,then analyzed their relationship . Results 45 subjects contain 225 vertebral bodies ,there were 38 vertebral bodies containing osteophyte visible to naked eye .The four types of MRI signal were type Ⅰ to type Ⅳ ,accounting for 2(5 .3% ) ,4(10 .5% ) ,10(26 .3% ) and 22(57 .9% ) ,respectively . The three types of CT structural characteristics are type A to type C ,accounting for 4(10 .5% ) ,11(28 .9% ) and 23(60 .5% ) ,re-spectively .The main MRI signal of type A is type Ⅱ(100% ) ,and that of type B and C are both type Ⅳ(72 .7% and 65 .2% ) .Con-clusion There is a corresponding relation between MRI signal type and CT structural characteristics on lumbar hyperostogeny . Constant reconstruction of osteophyte remodels vertebral body on degenerative lumbar spine .

ObjectiveTo investigate the variation of thalamus metabolism in patients with multiple sclerosis (MS) or neuronmyelitis optica (NMO) using 1H-MRS.Methods1H-MRS was performed to 32 MS patients (MS group),28 NMO patients (NMO group) and 35 healthy volunteers (normal control group).The ratios of metabolism in thalamus,including N-acetylaspartic acid/creatine (NAA/Cr),choline/creatine (Cho/Cr) and myo-inositol/creatine (mI/Cr) were calculated and compared.ResultsThere was statistical difference of NAA/Cr in thalamus among the three groups (P＜0.05).NAA/Cr in thalamus of MS group was significantly lower than that of normal control group (t= -3.45,P＜0.05),while no statistical difference of Cho/Cr and mI/Cr was found (t=0.086,0.661,all P＞0.05).No statistical difference of NAA/Cr,Cho/Cr or ml/Cr was found between NMO group and normal control group (t=-0.792,1.408,1.735,all P＞0.05).Conclusion1H-MRS shows the decrease of thalamus NAA/Cr that suggesting axon damage in MS patients,but in NMO patients no same result is found.1 H-MRS can reflect the pathological changes of MS and NMO,and improve the differential diagnosis of the two diseases.

Objective To evaluate the feasibility of CT subtraction angiography of the cerebral vessels with synchronous matched mask bone elimination (MMBE) technique, and to compare the imaging quality of MMBE with that of volume computed tomographic digital subtraction angiography (VCTDSA). Methods Vascular Vascular model was scanned with 64-slice spiral CT. Synchronous and asynchronous scans were independently performed for 10 times without contrast medium injection. ②Then with contrast medium injection, the same scans mentioned above were repeatedly performed each for 5 times. The imaging quality of MMBE was analyzed, which were reformatted and displayed with 3D volume rendering (VR) and maximum intensity projection (MIP). CT value of the overall view was measured on subtracted images (without contrast medium). Two sets of bone masks were extracted for subtraction and the imaging quality was evaluated (without contrast medium). Also the imaging quality of VCTDSA was compared with that of synchronous MMBE. Results With synchronous and asynchronous scan,imaging quality of MMBE was rated grade Ⅱ in 13 and grade Ⅲ in 2 times. There was no significant difference in the average CT value of subtracted images between the two methods(P>0.05). With synchronous scan, imaging quality of subtracted bone mask was rated gradeⅠ in 10 times. While with asynchronous scan, 1 time was grade Ⅰ, 8 were grade Ⅱ and 1 time was grade Ⅲ. The imaging quality of synchronous MMBE was rated grade Ⅱ in 13 times, grade Ⅲ in 2 times. For VCTDSA, the imaging quality was rated grade Ⅰ in 15 times. Conclusion Synchronous MMBE is a feasible imaging method for evaluation of cerebral vessels. The subtracted image quality is significantly improved with this technique. Imaging quality of VCTDSA is still superior to that of synchronous MMBE.