Amide proton transfer imaging of Alzheimer's disease and Parkinson's disease

Amide proton transfer (APT) magnetic resonance imaging (MRI) is an important molecularimaging technique at the protein level in tissue. Neurodegenerative diseases have a highlikelihood of causing abnormal protein accumulation in the brain, which can be detectedby APT MRI. This article briefly introduces the principles and image processing technologyof APT MRI, and reviews the current state of research on Alzheimer's disease and Parkinson's disease using this technique. Early applications of this approach in these twoneurodegenerative diseases are encouraging, which also suggests continued technicaldevelopment and larger clinical trials to gauge the value of this technique.

DIAGNOSTIC VALUE OF INTERICTAL DIFFUSION-WEIGHTED IMAGING IN EVALUATION OF INTRACTABLE TEMPORAL LOBE EPILEPSY

Objective To explore the ability of interictal diffusion-weighted imaging(DWI)to localize the temporal lobe of seizure origin and to predict postoperative seizure control in patients with temporal lobe epilepsy(TLE).Methods Twenty-seven patients with intractable TLE considered for surgery and 19 healthy volunteers were studied with conventional magnetic resonance imaging(MRI)and DWI.Apparent diffusion coefficients(ADCs)of bilateral hippocampi in both TLE patients and control subjects were obtained.Lateralization to either temporal lobe with hippocampal ADC was based on the threshold values derived from ±1SD of right/left ratios in normal subjects.And the postoperative pathology was reviewed.Results Hippocampal ADCs were higher on the side of surgery compared with those on the contralateral side as well as the ipsilateral side in control subjects [resected side(109.8±7.3)×10-5 cm2/s,contralateral side(91.7±4.7)×10-5 cm2/s,control subjects(81.6±5.2)×10-5 cm2/s,all P<0.01].Right/left hippocampal ADC ratio and conventional MRI lateralized to the operated temporal lobe in 21 of 27(77.8%)and in 18 of 27(66.7%)patients.Lateralization to the surgical side was not associated with postoperative seizure control with right/left hippocampal ADC ratio(P>0.05).Conclusions Conventional MRI is a sensitive method to detect hippocampal sclerosis.Accuracy of the right/left hippocampal ADC ratio for lateralizing to the side of surgery is very high,but it isn't a better predictor of surgical outcome.

EVALUATION OF CIRRHOTIC LIVER WITH PERFUSION-WEIGHTED MAGNETIC RESONANCE IMAGING:A PRELIMINARY EXPERIMENTAL STUDY IN ANIMAL MODELS WITH HALF-LIVER CIRRHOSIS

Objective To investigate the role of peffusion-weighted magnetic resonance imaging （MRI） in evaluation of cirrhotic fiver. Methods With a 4F catheter, 1% diluted carbon tetrachloride （ 1 ml/kg） was selectively injected into fight or left hepatic artery of 12 dogs fortnightly. The half fiver into which carbon tetrachloride was injected was called as study side （SS）, while the other half fiver without carbon tetrachloride injection was called as study control side （SCS）. Conventional and peffusion-weighted MRI were performed in every 4 weeks. Via a 4F catheter, 5ml gadolinium diethylentriamine pentaaceti acid （Gd-DTPA） dilution was injected into superior mesenteric artery at the 5th scan. The signal intensity-thne curves of SS, SCS, and portal vein were completed in MR workstation. The maximal relative signal increase （ MRSI）, peak time （ tp）, and slope of the curves were measured. Results On conventional MR images, no abnormalities of externality and signal intensity were observed in both SS and SCS of fiver at each stage. The mean tp, MP, SI, and slope of intensity-time curves in normal fiver were 10. 56 seconds, 1.01, and 10. 23 arbitrary unit （au）/s, respectively. Three parameters of curves didn＇t show obvious change in SCS of fiver at every stage. Abnormal perfusion curves occurred in SS of fiver at the 12th week after the 1st injection. The abnormality of perfusion curve in SS was more and more serious as the times of injection increased. The mean tp, IVlRSI, and slope intensity-time curves in SS of fiver were 19.45 seconds, 0. 43, and 3. 60 au/s respectively at the 24th week. Conclusion Perfusion-weighted imaging can potentially provide information about portal peffusion of hepatic parenchyma, and to some degree, reflect the severity of cirrhosis.

Hippocampal and thalamic neuronal metabolism in a putative rat model of schizophrenia°

The transcription factor early growth response protein 3 （EGR3） is involved in schizophrenia. We developed a putative rat model of schizophrenia by transfecting lentiviral particles carrying the Egr3 gene into bilateral hippocampal dentate gyrus. We assessed spatial working memory using the Morris water maze test, and neuronal metabolite levels in bilateral hippocampus and thalamus were determined by 3.0 T proton magnetic resonance spectroscopy. Choline content was significantly greater in the hippocampus after transfection, while N-acetylaspartate and the ratio of N-acetylaspartate to creatine/phosphocreatine in the thalamus were lower than in controls. This study is the first to report evaluation of brain metabolites using 3,0 T proton magnetic resonance spectroscopy in rats transfected with Egr3, and reveals metabolic abnormalities in the hippocampus and thalamus in this putative model of schizophrenia.

Cognitive magnetic resonance imaging-ultrasound fusion transperineal targeted biopsy combined with randomized biopsy in detection of prostate cancer

BACKGROUND Prostate cancer(PCa)is one of the most common cancers among men.Various strategies for targeted biopsy based on multiparametric magnetic resonance imaging(mp-MRI)have emerged,which may improve the accuracy of detecting clinically significant PCa in recent years.AIM To investigate the diagnostic efficiency of a template for cognitive MRIultrasound fusion transperineal targeted plus randomized biopsy in detecting PCa.METHODS Data from patients with an increasing prostate-specific antigen(PSA)level but less than 20 ng/mL and at least one lesion suspicious for PCa on MRI from December 2015 to June 2018 were retrospectively analyzed.All patients underwent cognitive fusion transperineal template-guided targeted biopsy followed by randomized biopsy outside the targeted area.A total of 127 patients with complete data were included in the final analysis.A multivariable logistic regression analysis was conducted,and a two-sided P<0.05 was considered statistically significant.RESULTS PCa was detected in 66 of 127 patients,and 56 cases presented clinically significant PCa.Cognitive fusion targeted biopsy alone detected 59/127 cases of PCa,specifically 52/59 cases with clinically significant PCa and 7/59 cases with clinically insignificant PCa.A randomized biopsy detected seven cases of PCa negative on targeted biopsy,and four cases had clinically significant PCa.PSA density(OR:1.008,95%CI:1.003-1.012,P=0.001;OR:1.006,95%CI:1.002-1.010,P=0.004)and Prostate Imaging-Reporting and Data System(PI-RADS)scores(both P<0.001)were independently associated with the results of cognitive fusion targeted biopsy combined with randomized biopsy and targeted biopsy alone.CONCLUSION This single-centered study proposed a feasible template for cognitive MRIultrasound fusion transperineal targeted plus randomized biopsy.Patients with higher PSAD and PI-RADS scores were more likely to be diagnosed with PCa.

Spontaneous remission of autoimmune pancreatitis: Four case reports

BACKGROUND Autoimmune pancreatitis(AIP)is a particular type of chronic pancreatitis,and steroid treatment of AIP is effective.Spontaneous remission(SR)of AIP without steroids is relatively rare.The international consensus for the treatment of autoimmune pancreatitis suggests that patients with AIP with obstructive jaundice,abdominal pain,and back pain related to the pancreas or the bile duct should be treated with steroids;most asymptomatic patients with AIP may improve without steroids.However,in our clinical work,we found that the clinical characteristics of AIP patients with SR vary.Four of these cases are described here.In addition,to our knowledge,there is no previously published report of dynamic imaging before and after SR of AIP at present.CASE SUMMARY We present the cases of four patients with AIP(two females and two males)in which the AIP improved spontaneously without steroid treatment.Two patients were asymptomatic,one patient had abdominal pain with obstructive jaundice,and one patient had intermittent right upper abdominal pain.Three patients presented with localized pancreatic enlargement and one with diffuse pancreatic enlargement.In addition to the pancreatic lesions,bile duct involvement was seen in two patients,and no extra-pancreatic organ involvement was found in the other two patients.The serum IgG4 level of all patients was more than twice the normal level.After SR in the four patients,the affected pancreases exhibited three types of image features:Return to normal,progressive fibrosis,and atrophy and calcification.CONCLUSION The clinical features of SR in our four patients with AIP differ,but the imaging findings share some characteristics.After SR,in some cases the affected pancreas could return to normal,although some patients suffer from progressive fibrosis and atrophy as well as calcification.

Central sensibility of human cases with different body mass during oral glucose tolerance test using functional magnetic resonance imaging

BACKGROUND： Because of the limitation of technique, there are few researches on regulating function o central hypothalamus by metabolism, especially the researches on real-time function. OBJECTIVE： To evaluate the response of hypothalamus to oral glucose tolerance test （OGTT） in differen body-weighted subjects by using functional magnetic resonance imaging （fMRI） so as to investigate th relationship between the sensitivity of hypothalamus in glycoregulation and disturbance of carbohydrate metabolism. DESIGN： Paired design. SETTING： Department of Radiology and Beijing Geriatrics Institute, Beijing Hospital, National Publi Health Bureau. PARTICIPANTS： A total of twenty healthy volunteers were selected from Beijing Geriatrics Institute National Public Health Bureau, including 10 subjects with obesity （5 males and 5 females; body mass 〉 28.0 kg/m2） and 10 subjects with normal body mass （5 males and 5 females; body mass from 18.5 to 23.9 kg/m2）. All subjects gave written informed consent before participating in the study. METHODS： fMRI study was performed on GE 1.5 T Signa Twinspeed Infinity with Excite. Each voluntee was ingested of glucose during the fMRI scan. T2＊ images were acquired using a single-shot gradient echo （EPI） technique. The parameters of EPI included： TR 3 000 ms, TE 40 ms, Flip angle 90°, field of view （FOV） 24 cm × 24 cm, thickness 5 mm, gap 0 mm, matrix 64 × 64, number of excitation 1. All 10 subjects with normal body mass underwent a repeat fMRI scan after consuming an equivalent amount o water without glucose on a separate day. The procedure for the fMRI scan with water intake was the same a for glucose ingestion. fMRI data were processed with Intensity Averaging Method. MAIN OUTCOME MEASURES： The central response of hypothalamus and feedback orientation during OGTT in different body-weighted subjects. RESULTS： An acute transient decrease of fMRI intensity in posterior inferior and anterior inferior o hypothalamus was observed in all subjects within 2 minutes after oral glucose intake. This decrease wa followed by a recovery to the baseline. However, obese subjects had a delayed intensity decrease [（1.96± 1.06） minutes vs. （1.04±0.71） minutes, t =2.14, P 〈 0.05] and longer recovery time [（26.62±7.35 minutes vs. （16.29±6.42） minutes, t =3.67, P 〈 0.01] as compared with normal body-weight subjects Furthermore, decreased fMRI intensity was significant different from baseline intensity [（5.7±2.5）% vs （14.3±5.5）%, t =2.56, P 〈 0.05] in obese subjects, but not in normal body-weight subjects. The area o hypothalamus in normal body-weight volunteers demonstrated no significant signal change before and afte oral water ingestion （P 〉 0.05）. CONCLUSION： Hypothalamus response to glucose loading is different in normal body-weighted and obes subjects. This suggests that fMRI is a useful tool to evaluate the central regulation of glucose metabolism.

Efficacy and safety of PD-1 blockade plus long-course chemoradiotherapy in locally advanced rectal cancer(NECTAR):a multi-center phase 2 study

Adding PD-1 blockade in the neoadjuvant regimens for locally advanced rectal cancer(LARC)patients with microsatellite stable(MsS)/mismatch repair-proficient(pMMR)tumors is an attractive,but debatable strategy.This phase 2,multicenter,prospective,single-arm study enrolled patients from 6 centers from June 2021 to November 2022.Locally advanced rectal cancer(LARC,cT_(3-4a)N_(0)M_(0) and cT_(1-4a)N_(1-2)M_(0))patients aged≥18 years with the distance from distal border of tumor to anal verge≤10 cm(identified by Magnetic Resonance Imaging)were qualifed for inclusion.The patients received long-course radiotherapy(50 Gy/25 fractions,2 Gy/fraction,5 days/week)and three 21-day cycles capecitabine(850-1000 mg/m2,bid,po,day1-14)and three 21-day cycles tislelizumab(200 mg,iv.gtt,day8)as neoadjuvant.Total mesorectal excision(TME)was 6-12 weeks after the end of radiotherapy to achieve radical resection.A total of 50 patients were enrolled in this study.The pathological complete response rate was 40.0%[20/50,95%confidence interval(CI):27.61-53.82%],while 15(30.0%,95%CI:19.1-43.75%),9(18.0%,95%CI:9.77-30.8%),2(4.0%,95%CI:1.10-13.46%)patients respectively achieved grade 1,2,and 3 tumor regression.Treatment-related adverse events(TRAEs)occurred in 28(56.0%)LARC patients,including 26(52.0%)with grade I-II and 2(4.0%)with grade II(1 with grade 3 immune-related colitis and 1 with grade 3 rash).PD-1 blockade plus long-course chemoradiotherapy(CRT)showed promising therapeutic effects according to pathological complete response rate and is well-tolerated in LARC patients.A larger randomized controlled study is desired to further validate the above findings.

DIFFERENTIATION BETWEEN MALIGNANT AND BENIGN OVARIAN TUMORS BY MAGNETIC RESONANCE IMAGING

Objective To determine the magnetic resonance （MR） imaging findings of an ovarian mass which are most predictive of malignancy and assess the value of intravenous gadolinium administration in the characterization of an ovarian mass. Methods Totally 74 consecutive patients with a clinically or sonographicaUy indeterminate adnexal mass underwent MR imaging, of whom 59 had subsequent surgical resection of 70 adnexal masses. These 59 patients formed the study population. MR imaging studies were prospectively and independently reviewed by a senior and a junior radiologist. The senior radiologist also reevaluated the studies in a blind fashion after a minimum 6 months interval. The sensitivity, specificity, positive predictive value, and negative predictive value of contrast-enhanced and unenhanced MR im- aging were evaluated Results The most predictive MR imaging findings for malignancy were presence of vegetations in a cystic lesinn and presence of necrosis in a solid lesion. The odds ratio was even higher when the ancillary finding of peritoneal metastasis or ascites was present. Contrast media contributed significantly to lesinn characterization. Total 70 ovarian masses were detected by contrast-enhanced MR imaging including 37 malignant ovarian masses and 33 benign ovarian masses with 87% （61/70）accuracy, 86% （32/37）sensitivity, 88% （29/33）specificity, 89% （32/36）positive predictive value, and 85% （29/34） negative predictive value, whereas 70 ovarian masses were detected by unenhanced MR imaging with 74% （52/70） accuracy, 73 % （27/37） sensitivity, 76 % （ 25/33 ） specificity, 77% （27/35） positive predictive value, and 71% （ 25/35 ） negative predictive value. There were significant differences in accuracy （ P 〈 0. 01 ）, sensitivity （ P 〈0. 01 ）, specificity （ P 〈0. 01 ） between contrast-enhanced and unenhanced MR imaging. Conclusion Contrast-enhanced MR imaging is highly accurate in detection and characterization of complex adnexal masses.

DIFFERENTIATION BETWEEN BENIGN PROSTATIC HYPERPLASIA AND PROSTATE CANCER IN THE TRANSITIONAL ZONE EVALUATED BY ~1H MAGNETIC RESONANCE SPECTROSCOPIC IMAGING

Objective To quantitatively evaluate the metabolic changes of benign prostatic hyperplasia(BPH) and prostate cancer in the transitional zone using magnetic resonance spectroscopic imaging(MRSI),and to analyze the characteristics and differences of the spectra in this zonal area.Methods Eighteen patients with prostate cancer in the transitional zone underwent magnetic resonance imaging(MRI)/MRSI examinations.The(Choline+Creatine)/Citrate(CC/Ci) ratio and the Choline/Creatine(Cho/Cr) ratio were evaluated in each voxel with cancer or BPH confirmed by pathological results.Discriminant analysis was used to determine the power of the two ratios in differentiation between cancer and BPH.Results The CC/Ci ratio and Cho/Cr ratio for cancer voxels were significantly higher than those in the voxels with BPH in the transitional zone(CC/Ci:2.36±1.31 vs.0.85±0.29,P<0.01;Cho/Cr:4.14±1.79 vs.1.26±0.45,P<0.01).As for the discriminant function with the CC/Ci ratio and the Cho/Cr ratio,the specificity,sensitivity,and accuracy were 98.6%,85.7%,92.9% respectively for the differentiation between cancer and BPH.Conclusions The prostate cancer is characterized by higher CC/Ci ratio and Cho/Cr ratio compared to BPH in the transitional zone.Both CC/Ci ratio and Cho/Cr ratio have high specificity,sensitivity,and accuracy in their discriminative power between cancer and BPH in this zonal area.

Amide Proton Transfer Magnetic Resonance Imaging of Alzheimer＇s Disease at 3.0 Tesla： A Preliminary Study

Background：Amide proton transfer （APT） imaging has recently emerged as an important contrast mechanism for magnetic resonance imaging （MRI） in the field of molecular and cellular imaging.The aim of this study was to evaluate the feasibility of APT imaging to detect cerebral abnormality in patients with Alzheimer＆#39;s disease （AD） at 3.0 Tesla.Methods：Twenty AD patients （9 men and 11 women; age range,67-83 years） and 20 age-matched normal controls （11 men and 9 women; age range,63-82 years） underwent APT and traditional MRI examination on a 3.0 Tesla MRI system.The magnetic resonance ratio asymmetry （MTRasym） values at 3.5 ppm of bilateral hippocampi （Hc）,temporal white matter regions,occipital white matter regions,and cerebral peduncles were measured on oblique axial APT images.MTRasym （3.5 ppm） values of the cerebral structures between AD patients and control subjects were compared with independent samples t-test.Controlling for age,partial correlation analysis was used to investigate the associations between mini-mental state examination （MMSE） and the various MRI measures among AD patients.Results：Compared with normal controls,MTRasym （3.5 ppm） values of bilateral Hc were significantly increased in AD patients （right 1.24% ± 0.21% vs.0.83% ± 0.19%,left 1.18% ± 0.18% vs.0.80%± 0.17%,t =3.039,3.328,P =0.004,0.002,respectively）.MTRasym （3.5 ppm） values of bilateral Hc were significantly negatively correlated with MMSE （right r =-0.559,P =0.013; left r=-0.461,P =0.047）.Conclusions：Increased MTRasym （3.5 ppm） values of bilateral Hc in AD patients and its strong correlations with MMSE suggest that APT imaging could potentially provide imaging biomarkers for the noninvasive molecular diagnosis of AD.

Evaluation of the Prostate Imaging Reporting and Data System for Magnetic Resonance Imaging Diagnosis of Prostate Cancer in Patients with Prostate-specific Antigen 〈20 ng/ml

Background： The European Society of Urogenital Radiology has built the Prostate Imaging Reporting and Data System （PI-RADS） for standardizing the diagnosis of prostate cancer （PCa）. This study evaluated the PI-RADS diagnosis method in patients with prostate-specific antigen （PSA） 〈20 ng/ml. Methods： A total of 133 patients with PSA 〈20 ng/ml were prospectively recruited. T2-weighted （T2WI） and diffusion-weighted （DWI） magnetic resonance images of the prostate were acquired before a 12-core transrectal prostate biopsy. Each patient＇s peripheral zone was divided into six regions on the images; each region corresponded to two of the 12 biopsy cores. T2WI, DWI, and T2W1 ＋ DWI scores were computed according to PI-RADS. The diagnostic accuracy of the PI-RADS score was evaluated using histopathology of prostate biopsies as the reference standard. Results： PCa was histologically diagnosed in 169 （21.2%） regions. Increased PI-RADS score correlated positively with increased cancer detection rate. The cancer detection rate for scores 1 to 5 was 2.8%, 15.0%, 34.6%, 52.6%, and 88.9%, respectively, using T2W1 and 12.0%, 20.2%, 48.0%, 85.7%, and 93.3%, respectively, using DWI. For T2WI ＋ DWI, the cancer detection rate was 1.5% （score 2）, 13.5% （scores 3-4）, 41.3% （scores 5-6）, 75.9% （scores 7-8）, and 92.3% （scores 9-10）. The area under the curve for cancer detection was 0.700 （T2WI）, 0.735 （DWI） and 0.749 （T2WI ＋ DWI）. The sensitivity and specificity were 53.8% and 89.2%, respectively, when The summed score ofT2Wl ＋ DWI

Longitudinal Alterations of Local Spontaneous Brain Activity in Parkinson's Disease

We used resting-state fMRI to evaluate longitu- dinal alterations in local spontaneous brain activity in Parkinson＇s disease （PD） over a 2-year period. Data were acquired from 23 PD patients at baseline and follow-up, and 27 age- and sex-matched normal controls. Regional homogeneity （ReHo） and voxel-based-morphometry （VBM） were used to identify differences in local sponta- neous brain activity and grey matter volume. With disease progression, we observed a progressive decrease in ReHo in the sensorimotor cortex, default-mode network, and left cerebellum, but increased ReHo in the supplementary motor area, bilateral temporal gyrus, and hippocampus. Moreover, there was a significant positive correlation between the rates of ReHo change in the left cerebellum and the rates of change in the Unified Parkinson＇s Disease Rating Scale-III scores. VBM revealed no significant differences in the grey matter volume among the three sets of acquisitions. We conclude that ReHo may be a suitable non-invasive marker of progression in PD.

Differentiation of Lymphoma Presenting as Retroperitoneal Mass and Retroperitoneal Fibrosis： Evaluation with Multidetector-row Computed Tomography

Background： Retroperitoneal fibrosis （RPF） and lymphoma presenting as retroperitoneal mass may closely resemble each other and misdiagnosis may occur. This study investigated the differential imaging features of RPF and lymphoma which presented as a retroperitoneal soft tissue using multidetector-row computed tomography （MDCT）. Methods： The 42 consecutive patients were included in this retrospective review, including 19 RPF patients （45.2%; including 13 males and 6 females; mean age： 56.7 ± 6.2 years） and 23 patients with lymphoma （54.8%： including 14 males and 9 females： mean age： 57.4 ± 12.3 years）. An array of qualitative computed tomography （CT） features of lesions in 42 consecutive patients with newly diagnosed untreated RPF and lymphoma were retrospectively analyzed. The quantitative size of the lesion at the para-aortic region and attenuation in the precontrast, arterial, and portal phases were calculated in regions of interest and compared between the patients with newly diagnosed untreated RPF and with lymphoma. Receiver operating characteristic curve analysis was used to assess the potential diagnostic value of each quantitative parameter. Inter-reader concordance was also calculated. Results： Mean ages between patients with RPF and lymphoma were not significantly different （56.7 ±6.2 years vs. 57.4 ± 12.3 years P = 0.595）. Compared to those in patients with lymphoma, homogeneous enhancement （65.2% vs. 94.7%, P = 0.027） and pelvic extension （52.2% vs. 89.5%, P= 0.017） were significantly more common while the involvement of additional nodes （78.3% vs. 5.3%, P 〈 0.001）, suprarenal extension （60.9% vs. 15.8%, P = 0.004）, and aortic displacement （43.5% vs. 5.3%, P 0.006） were significantly less common in patients with RPF. Lesion size at the para-aorta was significantly greater in patients with lymphoma, compared with RPF patients （3.9 ± 1.2 cm vs. 1.8 ± 0.6 cm; P 〈 0.001 ）. The attenuation values in three phases were not significantly different between patients with RPF and lymphoma. Inter-reader concordance for subjective features ranged from very good to excellent （range： 85.7 100.0%）. Conclusions： This study showed that MDCT can help differentiate between untreated RPF and lymphonla on the basis of qualitative CT features and lesion sizes. Differentiating RPF from lymphoma on the basis of attenuation values in the precontrast, arterial, and portal phases was difficult to accomplish.

Detection of atherosclerotic plaque progression in the abdominal aorta of rabbits with 3T magnetic resonance imaging

Background With features of high tissue contrast, MRI can be used for the qualitative and quantitative evaluation of atherosclerosis plaques. In this study we investigated the development of atherosclerosis plaque with high resolution 3T MRI in a rabbit model and compared the findings with the histopathological results. Method Twenty male New Zealand white rabbits were randomly allocated into an experimental group （n=16） and a control group （n=4）. Atherosclerotic lesions were induced in the abdominal aorta by balloon injury and cholesterol feeding. Multiple sequences MRI examination （ToF, TIWI, T2WI, and CE T1WI） were performed at the 2nd, 3rd, and 4th months after aortic denudation. Vessel wall thickness, total vessel area, lumen area, and vessel wall area were recorded. Plaque components were analyzed using histological results as a standard reference. Results Seventeen rabbits （14 in the experimental group and 3 in the control group） received all three MR examinations. Gradually, from 2 months to 4 months, vessel wall thickness and area in the experimental group increased significantly compared with the control group （P 〈0.01）. In the lumen area progressive stenosis was not found, even a slight dilation had developed in the experimental group. Lipid, fibrotic and calcified plaques can be differentiated by MR image. According to histological results, MRI had good performance in detection of lipid plaque. Conclusion MRI can be used to monitor progression of atherosclerosis and differentiate plaque components.

Differential temporal neural responses of pain-related regions by acupuncture at acupoint ST36： a magnetoencephalography study

Background Previous neuroimaging studies primarily focused on the spatial distribution of acupuncture needling stimulation. However, a salient feature of acupuncture was its long-lasting effect. This study attempted to detect the spatial-temporal neural responses evoked by acupuncture at an analgesia acupoint ST36 by using magnetoencephalography. To further verify its functional specificity, we also adopted acupuncture at Pericardium 6 and nonacupoint as separated controls.Methods Forty-two college students, all right-handed and acupuncture naive, participated in this study. Every participant received only one acupoint stimulation, resulting in 14 subjects in one group. Both magnetoencephalography data （151-channel whole-head system） and structural functional magnetic resonance imaging data （3D sequence with a voxel size of 1 mm3 for anatomical localization） were collected for each subject. All processing procedures were performed in BrainStorm Toolbox.Results Acupuncture at ST36 showed a significantly time-varied brain activities with different onset time. Our results presented that acupuncture at different acupoints （or comparing with nonacupoint） can specifically induce neural responses in different brain areas-acupuncture at ST36 can specifically induce the neural responses of pain-inhibition areas, while acupuncture at PC6 can specifically induce the activities of the insula and amygdala.Conclusions In the present study, we attempted to detect the temporal neural responses underlying the functional specificity of acupuncture at ST36, using acupoint belonging to different meridians and non-acupoint with efficacy-irreverent as separate controls. The specific neural substrates involving acupuncture at different acupoints may be related to its functional specificity in clinical settings.

Functional magnetic resonance imaging and immunohistochemical study of hypothalamic function following oral glucose ingestion in rats

Background The hypothalamus plays a central role in the regulation of metabolism by sensing metabolic demands and releasing regulatory neurotransmitters. This study investigated the response of the hypothalamus to glucose ingestion in rats by blood oxygen level-dependent functional magnetic resonance imaging （BOLD-fMRI） and immunohistochemical techniques to determine the role of the hypothalamus in glycoregulation during disturbances in carbohydrate metabolism. Methods The signal intensity of the hypothalamus was monitored by fMRI for 60 minutes after oral glucose intake in 48 healthy rats （age 14 months）, which included 24 normal weight rats （weighing （365±76.5） g） and 24 overweight rats （weighing （714±83.5） g）. Then, 12 rats （6 normal, 6 overweight） underwent a repeat fMRI scan after consuming an equivalent amount of water without glucose on a separate day. The procedure for fMRI with water intake was the same as for glucose ingestion, fMRI data was processed using time cluster analysis and intensity averaging method. After fMRI the expression of neuropeptide Y （NPY） and 5-hydroxytryptamine （5-HT） in the hypothalamus of all rats was determined by immunohistochemistry. Positive cells for NPY or 5-HT were counted. Results There was a transient, but significant, decrease in fMRI signal intensity in all rats （mean （3.12±0.78）%） in the hypothalamus within 19.5-25.5 minutes of oral glucose ingestion. In overweight rats, the decrease in signal intensity in response to the glucose ingestion was more markedly attenuated than that observed in normal weight rats （（2.2±1.5）% vs （4.2±0.7）% inhibition, t=2.12, P〈0.05）. There was no significant response in the hypothalamus after oral water ingestion. The percentage of NPY positive cells in obese rats were slightly lower than those in control group （21% vs 23% t=0.71, P〉0.05）; but there was no significant difference between the two groups; the percentage of 5-HT positive cells in obese rats were significantly lower than those in the control group （22% vs 31%, t=3.25, P〈0.01）. Conclusions There is a transient, but significant, decrease in BOLD signal intensity in the hypothalamus following glucose ingestion, which is similar to that observed in humans. The response of the hypothalamus to glucose ingestion was different in overweight and normal weight rats. The percentage of NPY positive cells in obese rats were lower than those in the control group, although this difference was not statistically significant. The percentage of 5-HT positive cells in obese rats was significantly lower than those in the control group.

Sustained Ventricular Tachycardia Secondary to Cardiac Metastasis of Lung Cancer

Although primary cardiac tumors are rare,cardiac metastasis of malignant tumors is not as infrequent as we might suspect.The pericardium is the most frequently involved site and myocardial involvement is less common.In this report,we present the case of a patient with a metastatic tumor on the left ventricular wall secondary to the lung cancer with sustained ventricular tachycardia （VT）.

Steel wire causing pseudoaneurysm of descending aorta

An l l-years-old boy presented with 7 days history of abdominal pain, precordial pain and intermittenthematemesis. The physical examination revealed appearance of anemia, precordial tenderness without other positive findings. Routine blood test was notable for Hb 60 g/L. Contrast CT scan of the chest revealed a soft tissue dense mass close to the descending aorta （Figure 1 A and B）. The mass and the adjacent artery were luminally connected and intensified substantially at the same time and to the same degree on the radiographic studies. The wall of the mass was slightly thickened and the inner surface of the wall was not smooth. The esophagus was deviated and became narrow due to compression （Figure 1 A）. Axial maximum intensity projection （MIP） showed a linear metallic foreign body （Figure I C） and local airway moved forward and became flat. Volume rendering （VR） confirmed a right- side protruding mass adjacent to the beginning of the descending aorta （Figure 1 D）. The gastroscopy showed ulceration of the esophageal mucosa （Figure 1 E）.

Study design of deep learning based automatic detection of cerebrovascular diseases on medical imaging: a position paper from Chinese Association of Radiologists

In recent years,with the development of artificial intelligence,especially deep learning technology,researches on automatic detection of cerebrovascular diseases on medical images have made tremendous progress and these models are gradually entering into clinical practice.However,because of the complexity and flexibility of the deep learning algorithms,these researches have great variability on model building,validation process,performance description and results interpretation.The lack of a reliable,consistent,standardized design protocol has,to a certain extent,affected the progress of clinical translation and technology development of computer aided detection systems.After reviewing a large number of literatures and extensive discussion with domestic experts,this position paper put forward recommendations of standardized design on the key steps of deep learning-based automatic image detection models for cerebrovascular diseases.With further research and application expansion,this position paper would continue to be updated and gradually extended to evaluate the generalizability and clinical application efficacy of such tools.