Application of fast susceptibility weighted imaging based on deep learning in assessment of acute ischemic stroke / 中华放射学杂志

Objective:To explore the value of fast susceptibility weighted imaging (SWI) generated by a deep learning model in assessment of acute ischemic stroke (AIS).Methods:From January 2019 to January 2021, 118 AIS patients [75 males and 43 females, aged 23-100 (66±14) years] who underwent MR examination and SWI sequence scanning within 24 h of symptom onset in the First Medical Center of PLA General Hospital were retrospectively analyzed. MATLAB ′s randperm function was used to divide 118 patients into a training set of 96 cases and a test set of 22 cases at a ratio of 8∶2. Fourty-seven AIS patients [38 males and 9 females, aged 16-75 (58±12) years] from one center of a multicenter study were selected to build the external validation set. SWI image and filtered phase image were combined into complex value image as full sampling reference image. Undersampled SWI images were obtained by retrospective undersampling of reference fully sampled images, and the undersampling multiple was five times which could save 80% of the scanning time, then the complex-valued convolutional neural network (ComplexNet) was used to develop reconstruct fast SWI. Interclass correlation coefficient (ICC) or Kappa tests were used to compare the consistency of image quality and the diagnostic consistency for the presence of susceptibility vessel sign (SVS), cerebral microbleeds and asymmetry of cerebral deep medullary veins (DMVs) in AIS patient on fully sampled SWI and fast SWI based on ComplexNet.Results:In test set, score of image quality was 4.5±0.6 for fully sampled SWI image and 4.6±0.7 for fast SWI based on ComplexNet, and coefficient was excellent (ICC=0.86, P<0.05). Full sampling SWI had good agreement with fast SWI based on ComplexNet in detecting SVS (Kappa=0.79, P<0.05), microbleeds (Kappa=0.86, P<0.05), and DMVs asymmetry (Kappa=0.82, P<0.05) in AIS patients. In the external validation set, score of image quality was 4.1±1.0 for fully sampled SWI image and 4.0±0.9 for fast SWI based on ComplexNet, and coefficient was excellent (ICC=0.97, P<0.05). Full sampling SWI had good agreement with fast SWI based on ComplexNet in detecting SVS (Kappa=0.74, P<0.05), microbleeds (Kappa=0.83, P<0.05), and DMVs asymmetry (Kappa=0.74, P<0.05) in AIS patients. Conclusions:Deep learning techniques can significantly accelerate the speed of SWI, and the consistency of image quality and detected AIS signs between fast SWI based on ComplexNet and fully sampled SWI is good. The fast SWI based on ComplexNet can be applied to the radiographic assessment of clinical AIS patients

Current applications for magnetic resonance-guided focused ultrasound in the treatment of Parkinson's disease / 中华医学杂志(英文版)

Magnetic resonance-guided focused ultrasound (MRgFUS) is a novel and minimally invasive technology. Since the US Food and Drug Administration approved unilateral ventral intermediate nucleus-MRgFUS for medication-refractory essential tremor in 2016, studies on new indications, such as Parkinson's disease (PD), psychiatric diseases, and brain tumors, have been on the rise, and MRgFUS has become a promising method to treat such neurological diseases. Currently, as the second most common degenerative disease, PD is a research hotspot in the field of MRgFUS. The actions of MRgFUS on the brain range from thermoablation, blood-brain barrier (BBB) opening, to neuromodulation. Intensity is a key determinant of ultrasound actions. Generally, high intensity can be used to precisely thermoablate brain targets, whereas low intensity can be used as molecular therapies to modulate neuronal activity and open the BBB in conjunction with injected microbubbles. Here, we aimed to summarize advances in the application of MRgFUS for the treatment of PD, with a focus on thermal ablation, BBB opening, and neuromodulation, in the hope of informing clinicians of current applications.

Collateral Flow in Magnetic Resonance Angiography:Prognostic Value for Vertebrobasilar Stenosis With Stroke Recurrence

Background@#and Purpose Intracranial vertebrobasilar atherosclerotic stenosis (IVBAS) is a major cause of posterior circulation stroke. Some patients suffer from stroke recurrence despite receiving medical treatment. This study aimed to determine the prognostic value of a new score for the posterior communicating artery and the P1 segment of the posterior cerebral artery (PCoA-P1) for predicting stroke recurrence in IVBAS. @*Methods@#We retrospectively enrolled patients with severe IVBAS (70%–99%). According to the number of stroke recurrences, patients were divided into no-recurrence, single-recurrence, and multiple-recurrences groups. We developed a new 5-point grading scale, with the PCoA-P1 score ranging from 0 to 4 based on magnetic resonance angiography, in which primary collaterals were dichotomized into good (2–4 points) and poor (0 or 1 point). Stroke recurrences after the index stroke were recorded. Patients who did not experience stroke recurrence were compared with those who experienced single or multiple stroke recurrences. @*Results@#From January 2012 to December 2019, 176 patients were enrolled, of which 116 (65.9%) had no stroke recurrence, 35 (19.9%) had a single stroke recurrence, and 25 (14.2%) had multiple stroke recurrences. Patients with single stroke recurrence (odds ratio [OR]= 4.134, 95% confidence interval [CI]=1.822–9.380, p=0.001) and multiple stroke recurrences (OR=6.894, 95% CI=2.489–19.092, p<0.001) were more likely to have poor primary collaterals than those with no stroke recurrence. @*Conclusions@#The new PCoA-P1 score appears to provide improve predictions of stroke recurrence in patients with IVBAS.

An investigation of the microstructure and mechanical properties of dental zirconia manufactured by digital light processing 3D printing / 华西口腔医学杂志

OBJECTIVES@#This study was performed to investigate the microstructure and mechanical properties of dental zirconia manufactured by digital light processing (DLP) 3D printing and the clinical application prospects of this material.@*METHODS@#The experiment (DLP) group was zirconia manufactured by DLP 3D printing, and the control (MILL) group was milled zirconia. The density, grain size, and phase composition were measured to study the microstructure. Flexural strength was measured by using three-point bending tests, while Vickers hardness was determined through a Vickers hardness tester. Fracture toughness was tested using the single-edge V-notched beam method.@*RESULTS@#Zirconia density of the DLP group was (6.019 8±0.021 3) g·cm@*CONCLUSIONS@#Zirconia manufactured by DLP 3D printing had microstructure and mechanical properties similar to those of the milled zirconia. Only the flexural strength and the Vickers hardness of the experimental zirconia were slightly lower than those of the milled zirconia. Therefore, DLP-manufactured zirconia has a promising future for clinical use.

Discussion on COPD Intestinal Dysfunction and Treatment with Traditional Chinese Medicine / 中国实验方剂学杂志

In China， about 100 million people currently have chronic obstructive pulmonary disease （COPD）. At the same time， COPD is a multisystem disease， not only affecting the function of musculoskeletal， cardiovascular， kidney and immune systems in patients， but also causing intestinal dysfunction as its extrapulmonary manifestations. From the perspective of traditional Chinese medicine （TCM）， after COPD is formed， deficiency， phlegm stasis and toxicity were accumulated in the lungs， which leads to dysfunction of lung in dispersing and descending， and eventually causes ascending and descending disorder of Qi activities， disorder of fluid supply and distribution， and stagnation of blood stasis. The viscera disease would affect the bowels， and the large intestine is thus affected. Modern medical discovers that， the lungs and intestines have common origins and similar physiological structures， in pathological circumstances， their common mucosal immune system may lead to similar immune factors and inflammatory manifestations in the lungs and intestines. At the same time， the studies have confirmed that there is also a close relationship between intestinal flora and lung， that is "lung-gut axis". These theories partially illustrate the mechanism of COPD in inducing intestinal injury. The specific manifestations of COPD intestinal dysfunction， ① Flora disorder， with increased abundance of intestinal gram-negative bacilli， and inhibited reproduction of Bifidobacterium， Lactobacillus and short-chain fatty acid-producing bacteria. ② Intestinal barrier damage： characterized by the destruction of intestinal epithelium tight connectivity， increased intestinal permeability， and thinning of the mucus layer. ③ Intestinal motility disorder： mostly manifested as weight loss and malnutrition. At present， for the intestinal dysfunction in COPD patients， most of the relevant discussions and targeted treatment methods in TCM are scattered and unsystematic. Guided by the idea of treating different diseases with the same treatment， we summarized the etiology and pathogenesis of COPD intestinal dysfunction by learning from the experience of TCM in treating intestinal flora disorders and inflammatory bowel disease， and proposed preliminary formulation with Tiaoqi Qushi，Tongfu Tongluo as its basic treatment principles in this paper， hoping to provide new ideas for the treatment of COPD.

Application of polymeric porcelain color-masking cast posts in the aesthetic repair of anterior teeth: a case report / 华西口腔医学杂志

Many patients with large-area tooth defect need cast post-core crown restoration. However, the color defect of the cast post-core will affect the final restorative result, especially that of the anterior teeth. A new technology of color masking by applying CERAMAGE polymeric porcelain to the cast metal post-core surface improves the color of a full-ceramic restoration of anterior teeth and may provide a new alternative for the aesthetic repair of anterior teeth with a large area of defective tooth.

Expression of IKBKE and NF-κB in pancreatic cancer and the effect of IKBKE on proliferation and migration of pancreatic cancer cells / 中华肝胆外科杂志

Objective:To investigate the expression of IKBKE and NF-κB in pancreatic cancer, and to explore the effect of IKBKE on pancreatic cancer proliferation and migration.Methods:Immunohistochemistry staining was used to study the expression of IKBKE and NF-κB in tissues of 61 pancreatic cancer patients admitted to the Second Hospital of Tianjin Medical University from January 2012 to January 2017 and 13 normal pancreatic tissues. The correlations between those expression to clinicopathological features were analyzed. Lentivirus mediated RNAi was transfected into pancreatic cancer cells to block IKBKE. Western blot was performed to test the silencing effeciency; CCK-8 and plate clone and scratch assays were used to investigate the proliferation and migration of pancreatic cancer.Results:Immunohistochemical staining showed that 60 (98.4%) of IKBKE staining were weakly positive, positive, and strongly positive in pancreatic cancer tissues, which were significantly higher than normal pancreatic tissues(76.9% cases were weakly positive and the rest were negative), and the differences were statistically significant ( P<0.05). All cases of NF-κB exhibited weakly positive expression and above in pancreatic cancer tissues, which was markedly higher than normal tissues (30.8% cases were weak positive and the rest were negative staining), statistically significant ( P<0.05). Survival analysis showed that patients with high level of IKBKE showed a shorter overall survival ( P<0.05). CCK-8, plate cloning and scratch assays showed that the proliferation and migration of were significantly decreased in IKBKE knocking down group ( P<0.05). Conclusions:IKBKE and NF-κB are highly expressed in pancreatic cancer, and IKBKE is correlated with NF-κB in pancreatic cancer. Blocking of IKBKE could distinctly inhibit the proliferation and migration of pancreatic cancer.

Effect of Zingiberis Rhizoma Recens on Hemorrhoids Model in Rats and Mice / 中国实验方剂学杂志

Objective: To explore the effect of Zingiberis Rhizoma Recens(ZRR) on hemorrhoids in mice and rats. Method: Sixty SPF-grade SD rats were divided into blank group, model group, Ma Yinglong Shexiang hemorrhoid ointment group (7.5 g·kg-1), and large and small-dose ZRR paste groups (10, 5 g·kg-1). ZRR paste was applied in Yongquan acupoint to observe the effect of 0.05 mL injection with 75% acetic acid solution on hemorrhoids induced by subcutaneous anus in rats, the levels of interleukin-1β (IL-1β), interleukin-6 (IL-6), tumor necrosis factor-α (TNF-α), nitric oxide (NO) in the serum were detected by enzyme linked immunosorbent assay(ELISA), and the rectal histopathology was detected by hematoxylin-eosin(HE). Sixty SPF-grade KM mice were divided into blank group, model group, MA Ying-long Shexiang hemorrhoid ointment group (7.5 g·kg-1), and large and small-dose ginger essential oil groups (0.06, 0.03 mL, three times a day). ZRR paste was applied in crissum to observe the effect of injection of 20% acetic acid solution 0.05 mL (maintaining for 1 min) on hemorrhoids in mice induced by anus. The degree of local swelling ulcer around the anus and score was observed, levels of IL-1β, TNF-α in the serum were determined by ELISA, and the rectal histopathology was detected by HE staining. Result: In the experimental study on treating hemorrhoids with ZRR paste applied on Yongquan point of rats, compared with normal group, serum levels of IL-1β, IL-6, TNF-α, NO in model group were significantly higher (Pβ, IL-6, TNF-α, NO were decreased in each administration group (PPPPβ, TNF-α in model group were significantly higher (PPβ, TNF-α levels (PPConclusion: External application of ZRR can effectively inhibit perianal swelling and ulcer degree, with a good therapeutic effect on hemorrhoids model in rats and mice.

Value of Minimum Apparent Diffusion Coefficient in Peritumoral Edema in the Differential Diagnosis between Primary Central Nervous System Lymphoma and Glioblastoma / 中国医学科学院学报

Objective To evaluate the role of minimum apparent diffusion coefficient(MinADC) values in peritumoral edema based on magnetic resonance diffusion weighted imaging in the differential diagnosis between primary central nervous system lymphoma(PCNSL) and glioblastoma(GBM).Methods ADC values in peritumoral edema were measured in 16 patients with PCNSL(diffuse large B cell lymphoma) and 31 patients with GBM(WHO grade 4) confirmed by pathology.Regions of interests were manually drawn on ADC maps on peritumoral edema regions to obtain the MinADC value.Independent samples t-test and receiver operating characteristic analysis were performed for statistical analysis.Results The MinADC value [(1.20-1.45)×10 mm/s,mean(1.35±0.68)×10 mm/s] in PCNSL was significantly higher than that in GBM [(0.95-1.31)×10 mm/s,mean(1.12±0.09)×10 mm/s](t=9.977,P=0.000).The area under the receiver operating characteristic curve was 0.986,and the cutoff value of MinADC was 1.245×10 mm/s for the differentiation between PCNSL and GBM,with the best combination of sensitivity(94.1%) and specificity(94.1%).Conclusion MinADC value can be a simple and effective measure for the differential diagnosis between PCNSL and GBM.

Value of Magnetic Resonance Imaging Findings in Differential Diagnosis between the Adult Reversible Splenial Lesion Syndrome and Ischemic Infarction of the Splenium of the Corpus Callosum / 中国医学科学院学报

Objective To evaluate the magnetic resonance imaging (MRI) findings in differential diagnosis between the adult reversible splenial lesion syndrome (RESLES) and ischemic infarction of the splenium of the corpus callosum (SCC). Methods The MRI findings and clinical data of 7 RESLES patients and 13 patients with ischemic infarction of SCC who were clinically diagnosed and treated in our center from May 2015 to June 2017 were analyzed retrospectively. The main MRI findings included location,morphology,signal intensity,maximum cross-sectional area,diffusion weighted imaging (DWI),and apparent diffusion coefficient (ADC) value. Results On the MRI findings of 7 RESLES patients (5 males and 2 females),the centers of all lesions of the SCC were located in the midline of SCC,the lesion shapes were round,ellipse,or spindle,and the distribution of the lesions was bilateral and symmetric as the center of the midline of SCC. The lesions were hyperintense on DWI,and the mean maximum cross-sectional area of lesions was (56.9±32.6) mm and the mean ADC value was (0.3963±0.0715) ×10 mm/s. On the review MRI,all the lesions disappeared (mean interval:10 days). On the MRI findings of 13 patients with ischemic infarction of SCC (10 males and 3 females),the lesions were irregular or patchy in shape and were almost laterally and asymmetrically distributed. The lesions were hyperintense on DWI,and the mean maximum cross-sectional area was (55.1±43.9) mm and the mean ADC value was (0.4978±0.0123) ×10 mm/s. The mean maximum cross-sectional area (t=0.096,P=0.925) and the ADC value (t=-1.988,P=0.062) were not significantly different between RESLES group and ischemic infarction of SCC group. Conclusions The location,morphology,and distribution of the SCC lesions and the co-existence of other lesions in the brain are helpful for the differential diagnosis between RESLES and ischemic infarction of SCC. However,the mean maximum cross-sectional area and the ADC value show no obvious difference between these two diseases.

The application of MR new technique in primary angiitis of the central nervous system / 实用放射学杂志

Objective To study imaging findings of primary angiitis of the central nervous system (PACNS) on MR new techniques,and to explore the diagnostic value of MR new techniques in this disease.Methods Seventeen cases who had been clinically diagnosed as PACNS were enrolled.All the cases underwent MR regular scans [T1 WI,T2 WI,diffusion weighted imaging(DWI),enhanced-enhanced T1 WI] and 3D-posudo-continuous arterial spin labeling (3D-PCASL).Some cases were scanned by using magnetic resonance angiography (MRA),susceptibility weighted imaging (SWI) and magnetic resonance spectrum (MRS) techniques.The regional cerebral blood flow (CBF) values were achieved based on ASL.The inter-group difference of the CBF values were analyzed by independent sample t test.Results Compared to the normal site,the CBF values in the lesion site were significant lower on PACNS (P=0.000).Of 13 patients scanned by SWI,10 cases showed low signal in the lesion.Of 14 patients scanned by MRS,10 cases showed N-acetylaspartic acid (NAA) peak decrease and Cho peak increase and 2 cases showed lactic acid(Lac) peak.Conclusion 3D PCASL can detect the hemodynamic abnormalities of PACNS.SWI can improve the ability of sensibility to observe the microbleed inside the lesion.MRS can explicit the extent of destruction and repairment of neurons in the lesion.Combining with the convention MR images can improve the understanding of the disease and the diagnostic accuracy.

Quantifying the Cerebral Hemodynamic Changes in Hypertensive Patients Using 3D Pseudo-continuous Arterial Spin Labeling / 中国医学科学院学报

Objective To investigate the cerebral hemodynamic changes in hypertensive patients using 3D pseudo-continuous arterial spin labeling(3D pCASL).Methods Fifty-eight hypertensive subjects and thirty-four age-matched healthy volunteers were recruited and scanned using the 3D whole-brain pCASL sequence.The regional cerebral blood flow(CBF)values were achieved based on 3D pCASL with SPM8 technique and were manually drawn. Results Compared with healthy volunteers,hypertensive patients had significantly lower CBF values in various regions,with statistical difference at the bilateral centrum semiovale(P=0.000,P=0.000),periventricular white matter(P=0.001,P=0.002),splenium of corpus callosum(P=0.003),frontal lobe(P=0.003),parietal lobe(P=0.014),occipital lobe(P=0.002),temporal lobe(P=0.006),medulla(P=0.012),pons(P=0.016),midbrain(P=0.034),cerebellum(P=0.000),and gray matter(P=0.001).Nevertheless,the CBF values in the thalami,globus pallidus,putamen,and genu of corpus callosum demonstrated no significant inter-group difference(all P>0.05).Conclusions 3D pCASL can be used to detect the subtle hemodynamic abnormalities even at the early stage of hypertension.The observed decrease in CBF in these regions may suggest an increased risk of cerebral small vessel diseases.

Multi-parameter arterial spin labeling versus dynamic magnetic-sensitive enhanced cerebral perfusion imaging for diagnosis of transient cerebral ischemic attack / 南方医科大学学报

<p><b>OBJECTIVE</b>To evaluate the clinical value of three-dimensional pseudo-continuous arterial spin labeling (3D pCASL) perfusion magnetic resonance imaging (MRI) and dynamic susceptibility contrast (DSC) enhanced perfusion MRI in the diagnosis of transient ischemic attack (TIA).</p><p><b>METHODS</b>Thirty-nine consecutive patients with suspected TIA underwent multi-modal MRI scans including DSC, magnetic resonance angiography (MRA), diffusion-weighted imaging (DWI) and 3D pCASL (post-labeling delay, PLD=1.5 s and 2.5 s) within 24 h of symptom onset. Cerebral blood flow (CBF) from ASL and the time to the maximum of tissue residual function (Tmax) map from DSC were calculated using AW workstation. DWI and MRA were applied to detect acute cerebral infarction and intracranial artery stenosis. Two neuroradilogists who were blinded to the patients' clinical data assessed the presence of perfusion deficit, ischemic lesion and the lesion sites both from 1.5 s, 2.5 s PLD ASL-CBF and DSC-Tmax independently, and then graded them. The differences in the ranking grades between 1.5 s, 2.5 s PLD ASL and DSC were analyzed, and the frequency of lesion detection was compared between ASL-CBF, Tmax and MRA combining DWI method.</p><p><b>RESULTS</b>No significant differences was found in hypoperfusion grades detected by 3D pCASL (including PLD1.5 s and 2.5 s) CBF and Tmax maps, while significant differences were detected between 1.5 s PLD ASL-CBF and MRA combining DWI method; ASL with PLD 1.5 s CBF detected ischemic lesions and lesion site significantly more frequently than MRA combining DWI method.</p><p><b>CONCLUSION</b>s Three dimensional pCASL is a non-invasive perfusion method free of radiation exposure, and short PLD ASL is more sensitive than long PLD ASL for detecting ischemic lesions and lesion sites.</p>

Quantitative Measurement of Cerebral Blood Flow in Enhanced Psedo-continuous Arterial Spin Labeling Perfusion Imaging in Patients with Intracranial Atherosclerotic Stenosis / 中国医学科学院学报

Objective To acquire cerebral blood flow (CBF) in patients with severe intracranial atherosclerotic stenosis with enhanced pseudo-continuous arterial spin labeling (e-pCASL) and compare it with the findings of dynamic susceptibility contrast-enhanced perfusion-weighted imaging (DSC PWI) and pseudo-continuous arterial spin labeling (pCASL). Methods A total of 39 consecutive patients with severe intracranial atherosclerotic stenosis were enrolled in this study. All these patients underwent e-pCASL, pCASL, and DSC PWI. Blood supply territory of the stenosed artery was outlined as region of interest (ROI) and a mirror ROI was applied. Ratios of CBF were calculated as value of ROI/value of mirror ROI. SNK variance analysis was conducted to compare the CBF values of three persufion methods. Factorial analysis of variance and Pearson were employed to analysis the difference and the correlation of e-pCASL CBF ratio, pCASL CBF ratio, and DSC PWI relative cerebral blood flow(rCBF) ratio. Results The e-pCASL CBF ratio, pCASL CBF ratio, and DSC PWI rCBF ratio were not significantly different (P=0.476). TTP showed the CBF ratios were not significantly different between the healthy side and diseased side in patients with severe intracranial atherosclerotic stenosis. ATT showed the correlations of pCASL CBF ratio and DSC PWI rCBF ratio were not affected by ATT. Conclusions e-pCASL with multiple-post labeling delay time and pCASL have good consistency with DSC PWI in the quantitative measurement of hypoperfusion pattern. As an accurate, simple, non-invasive, and repeatable technique, e-pCASL has good correlation with DSC PWI in the quantitative measurement of hypoperfusion pattern that is not affected by ATT.

Three-dimensional Arterial Spin-labeling Perfusion Imaging in Measuring the Dynamic Changes of Cerebral Blood Flow Between Plain and High Altitude Areas / 中国医学影像学杂志

PurposeIt is well known hypobaric hypoxia occurs with acute exposure to high altitude, with commonly associated change of cerebral blood flow (CBF). In this work, three-dimensional arterial spin-labeling (3D ASL) was used to monitor the change of CBF to further extend our understanding of hypobaric hypoxia.Materials and Methods Six healthy subjects were recruited for this study, they were asked to stay at high altitude areas for 5 days, and then returned to the plain. All subjects received MRI examination in both plain and high altitude areas using exactly the same 3.0T MR scanner. A total of 8 MR scans were performed, and all the parameters were kept the same, the changes of cerebral blood flow were observed.ResultsCBF increased obviously and reached its peak after acute exposure to high altitude, at the first day at high altitude, CBF measurements in global brain, grey matter and white matter increased signiifcantly compared to the plain, the difference was statistically significant (P<0.05); after that, the CBF measurements started to gradually decrease in the second day and a small climb on the third day at high altitude, then the CBF continued to drop after returning to sea level, even below that at sea level prior to departure. After 1 week back to the plain area, CBF measurements in global brain, grey matter and white matter were still lower than those before departure for high altitude areas, with a statistically signiifcant difference (P<0.05).ConclusionCBF measurements had obvious increase upon initial arrival at high altitude, and then the CBF continued to drop even below that at sea level prior to departure.

Inter-scanner reliability and reproducibility of three dimensional pseudo-continuous arterial spinlabeling MR perfusion of posterior circulation territory in healthy adults / 中华放射学杂志

Objective To assess the inter-scanner reliability and reproducibility of 3D whole-brain pseudo-continuous arterial spin labeling (pCASL) of posterior circulation territory in healthy adults.Methods Twelve healthy subjects were scanned twice on two different 3.0 T MR scanners with 3D wholebrain pCASL technique.Intervals between tests were among 10-15 days.The ASL data with two post labeling delay time (PLD) of 1.5 and 2.5 seconds were acquired during every scanning.The cerebral blood flow (CBF) values of posterior circulation territory including cerebellum,midbrain,pons,medulla oblongata,thalamus and occipital lobe were extracted based on SPM technique for comparison.The interscanner reliability and reproducibility were evaluated with the intraclass correlation coefficient (ICC) and Bland-Altman plot.Results The CBF values of posterior circulation territory were 36-47 ml · min-1 ·100 g-1 (PLD =1.5 s) and 36-46 ml · min-1 · 100 g-1 (PLD =2.5 s).Comparing the data between the two tests,the ICC was 0.851 at PLD =1.5 s and 0.914 at PLD =2.5 s.The Bland-Altman showed the reproducibility at PLD =2.5 s was better than that at PLD =1.5 s.Conclusions The 3D whole-brain pCASL technique is available for measuring the CBF at posterior circulation territory with high reliability and reproducibility especially using longer PLD.It can be used for MR multicenter study on blood flow of posterior circulation territory.

Retrospective analysis of therapeutic efficacy of haploidentical allogeneic hematopoietic stem cell transplantation for severe aplastic anemia / 中国实验血液学杂志

This study was purposed to investigate the therapeutic efficacy of haploidentical allogeneic hemopoietic stem cell transplantation (allo-HSCT) for severe aplastic anemia (SAA), and evaluate the safety of this treatment by retrospective analysis. A total of 21 patients with SAA (13 cases of SAA-I, 8 cases of SAA-II) were treated with haploidentical allo-HSCT. Donors were the relatives of the patients (12 were the parents, 9 were the siblings). The conditioning regimen contained cyclophosphamide, fludarabine and antithymocyte globulin. Methylaminopterin, mycophenolate mofetil and cyclosporin A were used for preventing graft versus host disease (GVHD). The chimerism rate was monitored periodically after successful graft. The long survival rate, incidence and severity of complication, such as GVHD, infection, and so on were analyzed. The results showed that 15 out of 21 patients were survived for 16 (3-46) months, survival rate was 71.4%. Graft tailure happened in one case who died of mycetes septicemia at 43 days after allo-HSCT. Two patients died of pulmonary infection at 6 days and 10 days respectively after transplantation. Rejection happened in one case at 3 months who died of pulmonary infection at 17 days after the second transplantation with the same donor. Two patients died of IV grade intestinal GVHD at 35 days and 52 days. GVHD occurred in 14 of 21 patients, the accumulative incidence was 66.7%, 5 cases of them were severe. It is concluded that the therapeutic efficacy of haploidentical allo-HSCT is effective for SAA and with slighter complications.

MR imaging features and clinical value of vestibular aqueduct and endolymphatic sac in patients with large vestibular aqueduct syndrome / 中华放射学杂志

ObjectiveTo investigate MR imaging features of endolymphatic sac and vestibular aqueduct in patients with large vestibular aqueduct syndrome (LVAS) and its correlation with hearing loss.MethodsMR imaging findings of LVAS were analyzed in 31 cases (62 ears) retrospectively.MR imaging features were grouped into 4 types.In the first type,the signals of endolymphatic and vesitibular aqueduct were hypointense without any hyperintense area.In the second type,the signals of endolymphatic sac and vestibular were hyperintense which were confined within vestibular fissure.In the third type,the area from vestibular aqueduct backward out of the edge of the petrous bone was hyperintense,but its lower boundary was above posterior semicircular.In the fourth type the area which was hyperintense was below the posterior semicircular.To avoid errors in visual inspection,the hyperintense and hypointense area of endolymphatic and the signal intensity of vestibular aqueduct and cerebrospinal fluid (CSF)were measured.The differences of signal intensity among the vestibular endolymphatic sac between the high-signal areas and lowsignal areas were compared with paired t-test.The correlation of the endolymphatic sac MRI classification and degree of hearing losswasanalyzedby correctedChi-squaretestandSpearmancorrelation analysis.ResultTen ears belonged to type Ⅰ (moderate hearing loss in 1 ear,severe in 4 ears,profound in 5 ears),17 ears belonged to type Ⅱ ( moderate hearing loss in 1 ear; severe in 5 ears,profound in 11 ears),23 ears to type Ⅲ (moderate hearing loss in 3 ear,severe in 5 ears,profound in 15 ears) and 12 ears belonged to Ⅳ(mild hearing loss in 1 ear,moderate in 1 ear,severe 3 ear,profound in 7 ears).The boundary between hyperintense and hypointense area was clear,and the signal intensity ratios was 2.02 ± 0.06.The signal ratios of hyperintense and hypointense area to vestibular and CSF were 0.95 ±0.12,0.49 ±0.10,0.99 ± 0.08 respecitively.So there was statistical significant difference between hyperintense and hypointense area ( t =- 24.966,P ＜ 0.05 ),but there was no statistical significant difference between hyperintense area and vesitbular( t =-24.966,P ＞ 0.05).There was no difference of hearing loss between different MRI types ( likelihood ratio =5.02,P ＞ 0.05 ).Conclusions Not only endolymphatic sac enlarged but also perilymph herniated into skeletal fissures of vestibular aqueduct in patients with LVAS.The signal intensity of the endolymphatic sac did not show significant correlation with degree of hearing loss.

Study of optic nerve in patients with neuromyelitis optica using diffusion tensor imaging / 中华放射学杂志

Objective To explore the diagnostic value of optic diffusion tensor imaging (DTI) in detecting the impairment of optic nerve in neuromyelitis optica (NMO) patients.Methods Conventional MRI and optic DTI were performed in 28 NMO patients and 38 normal controls (NC).Fractional anisotropy (FA) values were measured in the anterior part,middle part and posterior part of intraorbital segment of optic nerve.The patients were classified into 3 groups based on the impairment of vision and visual evoked potential (VEP): monocular impairment (MI) group,10 eyes; biocular impairment (BI) group,36 eyes;and normal-appearing (NA) group,10 eyes.All patients were performed with the evaluation of expanded disability status scale (EDSS).One-way analysis of variance (ANOVA),receiver operating characteristic (ROC) curve,and Spearman correlation analysis were performed among the subgroups of NMO and normal controls.Results There was significantly statistical difference between the four groups (F =43.54,P ＜0.01).Decreased FA values were demonstrated in the MI group (0.29 ±0.08),BI group (0.27 ±0.08),and NA group (0.35 ±0.13) compared with NC (0.45 ±0.07) (P ＜0.01).FA value in BI group was significantly lower than that of NA group(P ＜0.01).Area under curve by ROC analysis in NC vs MI,NC vs BI,NC vs NA,and NC vs NMO was 0.92,0.95,0.74,and 0.91,respectively.The diagnostic sensitivity of ROC was 80％,86％,50％,and 79％,respectively.The diagnostic specificity of ROC was 95％ for the each compared groups.FA value showed no correlation with EDSS for each NMO groups,and showed negative correlation with disease duration for BI group (r =-0.371,P ＜ 0.05).Conclusions Various degrees of optic nerve injuries,indicated by decreased FA value,are present in NMO patients,and optic DTI may be a simple and effective tool for the quantitative evaluation of optic nerve in NMO patients.

Imaging features of calcifying pseudoneoplasms of the neuraxis / 中华放射学杂志

Objective To identify the imaging characteristics of calcifying pseudoneoplasms of the neuraxis (CAPNON) and do literature review.Methods Five patients of pathologically-proved CAPNON underwent preoperative MR examination,among which 4 underwent CT scan,2 underwent DSA examination and 1 underwent SPECT. All imaging data were retrospectively analyzed with the emphasis on imaging characteristics.Results Five patients of CAPNON with the diameter of 1.5 to 5.0 cm were found in five patients ( Male 4 ; Female 1 ; age 25 to 60 years old ).Three lesions were located in the skull base,one was located in the cervical spine and one in the foramen magnum and upper cervical segment. All patients underwent MRI examination and 4 of them also took CT scanning.On plain CT,all lesions showed obvious calcification.On T1WI all masses showed hypointensity,and on T2WI 4 of the lesions showed iso- or hypointensity and 1 heterogeneous signal intensity. On contrast-enhanced MR images, peripheral enhancement was demonstrated in 3 lesions,homogeneous enhancement was found in case and one lesion showed no enhancement. The pathologic analysis indicated that inside the lesions were abundant calcification,fibroepithelial tissue and mucoid matrix and no edema was detected around the lesions.Conclusions CAPNON displayed the predilection to male adults and the neuraxis was the predilection site.Calcification on CT images,hypointensity on MR images and peripheral enhancement will be helpful for the diagnosis of CAPNON,but the final confirmation still needs the pathologic results.