Brine shrimp are an ideal bait for zebrafish with high protein content. In laboratory settings, brine shrimp eggs (BSEs) are commonly used to hatch for acquiring brine shrimp. However, not all BSEs are able to successfully hatch into brine shrimp. Actually, some unhatched BSEs (UBSEs) retain and are collected along with the brine shrimp as bait. The digestibility of UBSEs and their potential impact on the digestive system of zebrafish have not been demonstrated. In this study, high-resolution synchrotron radiation phase-contrast CT (PCCT) was used to show the internal structures of UBSEs. Morphological changes of UBSEs were investigated after digestion in zebrafish intestines. The visualization of shell rupturing, collapsing, and shattering of UBSEs reveals that zebrafish intestines exerted much extra useless effort to digest the UBSEs. The results indicate that UBSEs should be completely discarded from the bait of brine shrimp before feeding zebrafish.

Micro and small organisms (MSOs) are essential components of the ecosystem. Many MSOs reproduce by hatching eggs, making it crucial to study the morphology of these eggs and their incubation products (IPs) in related research. Phase-contrast CT (PCCT) is a powerful imaging modality known for its high resolution and sensitivity to soft tissues. In this study, an ultrafast PCCT system was used to scan brine shrimp eggs (BSEs) before hatching to determine their viability. High-resolution PCCT was used to reveal the microstructures of BSEs and IPs. We found that normal BSEs have an exclusively regular structure, making them easily identifiable. The use of ultrafast PCCT not only allowed for quick determination of BSE viability but also significantly reduced the amount of irradiation exposure to the eggs. All of the normal BSEs that were tested successfully hatched into brine shrimp, demonstrating the high safety of ultrafast PCCT. The high-resolution PCCT images clearly showed the formation of hatching membranes, cracks, and deformable bodies during the hatching process. The results suggest that ultrafast PCCT has the potential to assess the viability of MSO eggs, while high-resolution PCCT can provide valuable insight into the morphological changes that occur during the hatching process.

Background:Accurate staging of hepatic fibrosis is critical for prognostication and management among patients with chronic liver disease, and noninvasive, efficient alternatives to biopsy are urgently needed. This study aimed to evaluate the performance of an automated deep learning (DL) algorithm for fibrosis staging and for differentiating patients with hepatic fibrosis from healthy individuals via magnetic resonance (MR) images with and without additional clinical data. Methods:A total of 500 patients from two medical centers were retrospectively analyzed. DL models were developed based on delayed-phase MR images to predict fibrosis stages. Additional models were constructed by integrating the DL algorithm with nonimaging variables, including serologic biomarkers [aminotransferase-to-platelet ratio index (APRI) and fibrosis index based on four factors (FIB-4)], viral status (hepatitis B and C), and MR scanner parameters. Diagnostic performance, was assessed via the area under the receiver operating characteristic curve (AUROC), and comparisons were through use of the DeLong test. Sensitivity and specificity of the DL and full models (DL plus all clinical features) were compared with those of experienced radiologists and serologic biomarkers via the McNemar test. Results:In the test set, the full model achieved AUROC values of 0.99 [95% confidence interval (CI): 0.94-1.00], 0.98 (95% CI: 0.93-0.99), 0.90 (95% CI: 0.83-0.95), 0.81 (95% CI: 0.73-0.88), and 0.84 (95% CI: 0.76-0.90) for staging F0-4, F1-4, F2-4, F3-4, and F4, respectively. This model significantly outperformed the DL model in early-stage classification (F0-4 and F1-4). Compared with expert radiologists, it showed superior specificity for F0-4 and higher sensitivity across the other four classification tasks. Both the DL and full models showed significantly greater specificity than did the biomarkers for staging advanced fibrosis (F3-4 and F4). Conclusions:The proposed DL algorithm provides a noninvasive method for hepatic fibrosis staging and screening, outperforming both radiologists and conventional biomarkers, and may facilitate improved clinical decision-making.

Cerebral infarction is the second leading cause of death in the world,and has become the most serious cause of disability and death in China.Acute ischemic stroke(AIS)is the most common type of cerebral infarction,accounting for about 80%of all cerebral infarctions.Hemorrhagic transformation(HT)is one of the natural regression processes in pa-tients with AIS,and is the most serious complication after treatments[such as intravenous thrombolysis(IVT)or endovascu-lar thrombectomy(EVT)],which brings a heavy burden for patients and their families and even the all society.Accurate pre-diction and evaluation are of important clinical significance.In recent years,imaging research has focused on the value of CT and MRI in evaluating HT.The diagnostic value of CT plain scan is limited.Before AIS treatment,an early diagnostic score≤7 points in the Alberta Cerebral Infarction Plan is associated with the occurrence of HT(P=0.033),and high-density middle cerebral artery sign is an independent risk factor for the occurrence of HT(OR=10.334).For AIS patients treated with thrombectomy within 2-7 days,dual energy CT scanning at 24 hours after therapy had a high efficacy for prediction of HT occurrence,with a sensitivity of 82.5%and specificity of 100%.CT angiography suggests that patients with high thrombus burden had a higher probability of developing HT(OR=1.28).The incidence of HT in AIS patients with good collateral circulation is low.CT perfusion imaging parameters,including surface permeability,cerebral blood volume,Tmax,etc.,have good predictive value for predicting HT occurence.In MRI plain scan,high signal on FLAIR can predict the occurrence of HT.The volume of high signal areas on MRI diffusion-weighted imaging can predict HT,with area under the ROC curve of 0.78.Brush like sign,and micro bleeding lesions on sensitivity weighted MRI indicate the occurrence of HT.Enhanced T1 weighted imaging of MRI shows a significant correlation between brain parenchymal enhancement and HT oc-currence(P<0.05).Perfusion weighted imaging of MRI shows a decrease in cerebral blood flow(CBV)in the infarcted area may predict HT occurence.In addition,the CT and MRI image post-processing system RAPID has improved the evaluation efficiency for HT occurrence.In the future,personalized imaging detection methods and processes should set up based on the hardware and local medical conditions of each emergency center for HT management.

Angiostrongylus cantonensis, a zoonotic parasite, can invade the human central nervous system (CNS) and cause acute eosinophilic meningitis or eosinophilic meningoencephalitis. Mice infected with A. cantonensis show elevated levels of pro-inflammatory cytokines, plasminogen activators, and matrix metalloproteinase-9, resulting in disruption of the blood–brain barrier (BBB) and immune cell infiltration into the CNS. Caveolin-1 (Cav-1) regulates the permeability of the BBB, which affects immune cells and cerebrospinal fluid. This intricate interaction ultimately fuels the progression of brain damage and edema. This study aims to investigate the regulatory role of Cav-1 in the pathogenesis of meningoencephalitis induced by A. cantonensis infection. We investigated pathological alterations by triphenyl-tetrazolium chloride, brain water content, BBB permeability, Western blot analysis, and gelatin zymography in BALB/c mice after A. cantonensis. The study evaluates the critical role of Cav-1 regulation through the TLR4/MyD88 signaling pathway, modulates tight junction proteins, influences BBB permeability, and contributes to brain damage in A. cantonensis-induced meningoencephalitis.

目的：评估 18 F-氟脱氧葡萄糖正电子发射断层扫描/磁共振成像( 18 F-fluorodeoxyglucose positron emission tomography/magnetic resonanceimaging, 18 F-FDG PET/MRI)在胰腺癌术后复发诊断中的价值。方法：连续纳入2018年4月至2023年12月期间86例胰腺癌切除术后的患者，在2024年8月至9月行 18 F-FDG PET/MRI检查。回顾性分析 18 F-FDG PET/MRI检测胰腺癌术后复发的效能，比较PET/MRI和血清糖类抗原19-9（CA19-9）水平在诊断复发的效能。结果：经随访证实，86例患者中有67.4%（58/86）发生了肿瘤复发。复发组的原发肿瘤直径大于未复发组[（3.4±1.3）cm比（2.7±1.2）cm]。复发的患者中，87.9%（51/58）为系统性复发，最常见的是肝脏转移和腹膜转移。PET/MRI检查结果改变了30.2%（26/86）患者的治疗方案。86例中，有79例患者同时检查了PET/MRI和血清CA19-9，在诊断胰腺癌术后复发中，PET/MRI显示出比血清CA19-9更高的诊断效能（AUC:0.847对0.719）。PET/MRI检出9/12例血清CA19-9正常的胰腺癌复发，排除了5/8例血清CA19-9升高的未复发患者。结论：PET/MRI在胰腺癌术后复发诊断中具有较大的临床价值，其不仅能诊断是否复发，还能提供肿瘤复发的具体部位，对于血清CA19-9正常的患者，PET/MRI检查更有意义，为下一步治疗方案的制定提供全面的信息。

BACKGROUND:Mild asymptomatic intracranial atherosclerotic stenosis (aICAS) is common in Chinese patients with hypertension. However, there are no data on its prognostic value in this population. The aim of the present study was to clarify the prevalence and associated cardiovascular risk factors of mild aICAS and determine its prognostic value for overall and cardiovascular mortality in patients with hypertension. METHODS:In total, 1,813 participants were evaluated for aICAS using computed tomographic angiography. The predictive effect of mild to severe aICAS on all-cause and cardiovascular mortality was evaluated using Kaplan-Meier survival curves and Cox regression analyses. RESULTS:The prevalence rate of mild aICAS was 35.7%. Poorly controlled hypertension, in combination with diabetes and dyslipidemia, was associated with aICAS. Patients with aICAS had an independently significant increase in the risk of all-cause and cardiovascular death, with adjusted hazard ratios (HRs) for mild to severe stenosis ranging from 1.56 to 3.30 for all-cause death and from 2.48 to 6.38 for cardiovascular death. Among the patients with mild aICAS, only those with more than two stenoses had increased mortality after adjustment, with an HR of 2.44 (95% CI: 1.42-4.18) for total death and 4.49 (95% CI: 1.82-11.05) for cardiovascular death. CONCLUSIONS:A significant association between mild aICAS and mortality in stroke-free patients with hypertension was revealed. The results indicate that mild aICAS might be an imaging marker for cerebrovascular lesions in patients with hypertension and poor control of blood pressure and lipids in this population requires further research.

目的:分析肾上腺皮质腺癌(adrenocortical carcinoma,ACC)的CT、MRI表现特点,并探讨二者诊断ACC的价值.方法:回顾分析经手术及病理检查证实的39例ACC患者的CT、MRI平扫及增强检查表现及临床资料,总结对ACC有较大诊断价值的影像学征象,比较2种成像技术在ACC诊断中的价值.结果:14例患者同时完成了 CT和MRI平扫加增强检查,22例患者仅接受了 CT平扫加增强检查,3例患者仅接受了 MRI检查.39例ACC患者中,38例肿瘤为单侧发病(左侧19例、右侧19例),1例为双侧发病;23例肿瘤呈分叶状,16例呈类圆形;肿瘤直径为4.0～17.3 cm.CT、MRI检查中,分别有47.2％、82.4％的病例病灶内存在出血灶;91.7％、50％的病例发现肿瘤内增粗、迂曲的肿瘤血管影;77.8％、82.4％的病例提示包膜不光整.所有肿瘤均呈不均匀强化,肿瘤实性成分多呈中度增强;少量病例可见钙化、周围脏器血管受累、腹膜后淋巴结及远处肿瘤转移.14例同时完成CT和MRI平扫加增强检查的病例中,2种成像技术分别发现肿瘤灶内出血6例、12例,肿瘤内增生血管12例、6例,包膜不光整9例、12例.结论:ACC的CT、MRI表现具有一定特征性,多表现为体积较大(直径多大于4 cm),病灶呈分叶状,内多见肿瘤血管、出血坏死,肿瘤累及包膜;增强后多呈中度不均匀强化.CT在检出肿瘤血管影方面具有一定优势,而MRI在显示肿瘤内出血方面具有一定优势.

Lymphangioleiomyomatosis(LAM)is a rare multisystem neoplastic disease and is primarily affected women of childbearing age and premenopausal women.LAM lesions involve the lungs[known as pulmonary Lymphangi-oleiomyomatosis(PLAM)],kidneys[such as angiomyolipoma(AML)],and the lymphatic system(including lymphangioleio-myomas and chylous effusions).As the disease progresses,LAM disrupts lung tissue,alters lung structure,and leads to the development of lymphangioleiomyomas in the chest and abdominal lymphatic ducts.Early symptoms in LAM patients are mild,and clinical presentations lack specificity,making misdiagnosis common.Death can occur due to pulmonary function deterioration and recurrent pneumothorax.Currently,lung transplantation is considered the only effective treatment,al-though recurrence rates are relatively high.High-resolution computer tomography(HRCT)of the chest is a key diagnostic tool for LAM,which aid not only in the diagnosis but also in assessing the severity and prognosis of the condition.With the rapid development of medical imaging technology,particularly the use of photon counting detector CT(PCD-CT),which of-fers high resolution and noise reduction capabilities,significant improvements in image quality can be achieved.Compared to traditional CT scans,PCD-CT reduces radiation exposure by 35.7%,making it highly suitable for diagnosing and long-term monitoring of LAM.

Compared with MR plain scanning, gadolinium (Gd)-enhanced MR scanning can provide more diagnostic in-formation. Gadopentetate dimeglumine is generally used as an MR enhancement contrast agent in some coun-tries. It is a member of linear Gd-based contrast agents (GBCAs) which are considered more likely to release free Gd ions (Gd3+) than macrocyclic GBCAs. Gd3+ is one of the most effective known calcium antagonists, and can compete with calcium ions (Ca2+) in Ca2+-related biological reactions. In this study, animal models of tissue regeneration were established by cutting the caudal fins of zebrafish, and the models were exposed with gadopentetate dimeglumine solution for different immersion times of 1, 3, and 5 min. Three GBCA exposures per week were performed in the first 3 weeks of the follow-up time. Morphological parameters such as regenerative area (RA), bone density, bone thickness and regenerative bone volume (RBV) were quantified using a camera and synchrotron radiation micro CT. RA decreased as total Gd intake increased in both the female group (rho =-0.784, P < 0.0001) and the male group (rho =-0.471, P = 0.011). The bone density of the regenerated bone increased after Gd exposure in the treated groups. The morphology of the regenerated bone from the treated groups became shorter and thicker. Our results showed that gadopentetate dimeglumine had osteogenic toxicity in zebrafish.

Background:GE Healthcare's new generation of deep-learning image reconstruction (DLIR), the Revolution Apex CT is the first CT image reconstruction engine based on a deep neural network to be approved by the US Food and Drug Administration (FDA). It can generate high-quality CT images that restore the true texture with a low radiation dose. The aim of the present study was to assess the image quality of coronary CT angiography (CCTA) at 70 kVp with the DLIR algorithm as compared to the adaptive statistical iterative reconstruction-Veo (ASiR-V) algorithm in patients of different weight.Methods:The study group comprised 96 patients who underwent CCTA examination at 70 kVp and were subdivided by body mass index (BMI) into normal-weight patients [48] and overweight patients [48]. ASiR-V40%, ASiR-V80%, DLIR-low, DLIR-medium, and DLIR-high images were obtained. The objective image quality, radiation dose, and subjective score of the two groups of images with different reconstruction algorithms were compared and statistically analyzed.Results:In the overweight group, the noise of the DLIR image was lower than that of the routinely used ASiR-40%, and the contrast-to-noise ratio (CNR) of DLIR (H: 19.15±4.31; M: 12.68±2.91; L: 10.59±2.32) was higher than that of the ASiR-40% reconstructed image (8.39±1.46), with statistically significant differences (all P values <0.05). The subjective image quality evaluation of DLIR was significantly higher than that of ASiR-V reconstructed images (all P values <0.05), with the DLIR-H being the best. In a comparison of the normal-weight and overweight groups, the objective score of the ASiR-V-reconstructed image increased with increasing strength, but the subjective image evaluation decreased, and both differences (i.e., objective and subjective) were statistically significant (P<0.05). In general, the objective score of the DLIR reconstruction image between the two groups increased with increased noise reduction, and the DLIR-L image was the best. The difference between the two groups was statistically significant (P<0.05), but there was no significant difference in subjective image evaluation between the two groups. The effective dose (ED) of the normal-weight group and the overweight group was 1.36±0.42 and 1.59±0.46 mSv, respectively, and was significantly higher in the overweight group (P<0.05).Conclusions:As the strength of the ASiR-V reconstruction algorithm increased, the objective image quality increased accordingly, but the high-strength ASiR-V changed the noise texture of the image, resulting in a decrease in the subjective score, which affected disease diagnosis. Compared with the ASiR-V reconstruction algorithm, the DLIR reconstruction algorithm improved the image quality and diagnostic reliability for CCTA in patients with different weights, especially in heavier patients.

肝细胞癌(HCC)是全球癌症相关死亡的第三大原因.原发性肝癌是一组肝内异质性癌症,其中HCC是最常见的肿瘤[1],占原发性肝癌的90％.虽然病毒性肝炎仍是我国HCC发生最常见的危险因素,但NAFLD已取代病毒性肝炎成为我国最常见的慢性肝病,这也是目前非病毒性HCC迅速增长的原因.目前靶向治疗和免疫治疗成为晚期HCC临床研究的热点.如何筛选出免疫治疗优势人群的生物标志物,优化HCC患者的治疗方案成为了目前的研究重点.有研究表明,非病毒性HCC肿瘤细胞内脂肪变性可能是预测免疫治疗疗效的新型成像生物标志物.

Zebrafish are widely used as experimental animal models. They are small and move fast in the water. Real-time imaging of fast-moving zebrafish is a challenge, and it requires that the imaging technique has higher spatiotemporal resolution and penetration ability. The purpose of this study was to evaluate the feasibility of dynamic phase retrieval (PR)-based phase-contrast imaging (PCI) for real-time displaying of the breathing and swimming process in unanesthetized free-moving zebrafish, and to evaluate the feasibility of PR-based phase-contrast CT (PCCT) for visualizing the soft tissues in anesthetized living zebrafish. PR was performed using the phase-attenuation duality (PAD) method with the δ/β values (PAD property) of 100 and 1000 for dynamic PR-based PCI and PR-based PCCT, respectively. The contrast-to-noise ratio (CNR) was used for quantitatively assessing the visibility of the adipose tissue and muscle tissue. The skeleton and swim bladder chambers in fast-moving zebrafish were clearly shown. The dynamic processes of breathing and swimming were visibly recorded. The respiratory intensity and frequency and the movement flexibility of the zebrafish could be dynamically evaluated. By producing more obvious image contrast, PR-based PCCT clearly showed the adipose tissue and muscle tissue. The CNRs from PR-based PCCT were significantly higher than those from PR-free PCCT for both adipose tissue (9.256 ± 2.037 vs. 0.429 ± 0.426, p < 0.0001) and muscle tissue (7.095 ± 1.443 vs. 0.324 ± 0.267, p < 0.0001). Dynamic PR-based PCI holds the potential for investigating both morphological abnormalities and motor disorders. PR-based PCCT offers clear visualization and the potential for quantification of soft tissues in living zebrafish.

Objective: To evaluate value of blood oxygen level-dependent (BOLD) magnetic resonance imaging (MRI) for early renal hypoxia assessment in chronic kidney disease(CKD). Methods: Fifty-two patients with CKD and 52 age- and sex-matched health volunteers underwent BOLD MRI of the kidneys. Serum creatinine (sCr) levels and estimated GFR (eGFR) were collected. The patients were classified into 5 stages according to the National Kidney Foundation′s Kidney Disease Outcomes Quality Initiative. Difference in R2*s were compared between patients and volunteers and among different stages of CKD. Results: In patients with CKD and volunteers, R2* of renal medulla was higher than that of renal cortex (P<0.05). Compared with those of volunteers, medulla R2*s in patients with CKD were significantly lower [(16.40 ± 2.47)/s vs (18.17± 2.38)/s, P<0.05]. There were no differences in cortical R2*s among CKD stages and volunteers (P>0.05). However, medullar R2*s were lower in patients with CKD1 [(16.55 ± 2.12)/s], CKD4 [(16.48 ± 2.95)/s], or CKD5 [(13.99 ± 2.21)/s] than those in volunteers [(18.17± 2.38)/s] (P<0.05). Conclusions: BOLD MRI is sensitive to renal medullary hypoxia, and which is helpful for diagnosing early stage of CKD.

目的:探讨基于CT图像的纹理分析对CT引导下经皮肺穿刺出血并发症的预测价值.方法:回顾性分析130例行CT引导下经皮肺穿刺活检患者的术前平扫图像,术区有大于或等于2级肺出血者为有出血组,0级或1级肺出血者为无/少量出血组.首先随机选取100例作为训练组,采用MaZda软件,分别手动勾画出平扫肺窗图像上预穿刺路径周边的肺野作为感兴趣区(ROI),分别通过Fisher系数、分类错误概率联合平均相关系数(POE+ACC)、交互信息(MI)法筛选出区分出血组及无/少量出血组最具有价值的纹理特征,然后分别采用原始数据分析(RDA)、主要成分分析(PCA)、线性分类分析(LDA)和非线性分类分析(NDA)四种特征分类统计方法进行判断,结果以错判率形式表示;最后再根据得到的最优纹理参数及特征分类方法分别对另外30例图像加以验证.结果:以穿刺路径周边的肺野作为ROI时,最低错判率为11.00％(11/100),该结果出现在特征选择方法采用POE+ACC或MI,特征分类统计方法采用NDA时,以此结果进行验证的错判率分别为13.33％(4/30)和16.67％(5/30),两者差异无统计学意义.结论:分析预穿刺路径周边肺野的纹理特征有助于预测CT引导下肺穿刺并发出血的风险,为选择合适的穿刺路径以减少肺出血并发症提供依据.

Background: In addition to contrast-enhanced multiphase computed tomography (CT) and magnetic resonance imaging (MRI), integrated positron emission tomography (PET)/magnetic resonance (MR) is increasingly being used for the preoperative evaluation of pancreatic cancer. The purpose of this study was to explore the value of hybrid 18F-fluorodeoxyglucose (18F-FDG) PET/MR imaging in preoperative assessment and treatment decision-making. Methods: A retrospective data collection (of imaging, clinical, and pathological information) was conducted on patients who underwent 18F-FDG PET/MR with clinically diagnosed or suspected pancreatic cancer from March 2018 to March 2022 in Ruijin Hospital. The data of 76 patients were initially included, with 1 of the 76 patients eventually being excluded due to a misdiagnosis of inflammatory disease. Of the 75 patients, 38 underwent pancreatic tumor resection and 10 underwent laparoscopic exploration. The accuracy of 18F-FDG PET/MR for pancreatic cancer staging and the assessment of pancreatic resectability was evaluated based on pathological results, intraoperative findings, and documented final clinical stages of illness. The adjustments to patient treatment plans were also analyzed before and after 18F-FDG PET/MR examination. Results: The accuracy of clinical tumor node metastasis (TNM) staging of pancreatic cancer by 18F-FDG PET/MR was 73.3% (55/75). The area under the curve (AUC) of 18F-FDG PET/MR for diagnosing the advanced stage (III–IV) versus the nonadvanced stage (I–II) of disease was 0.922 [95% confidence interval (CI): 0.852–0.993]. The treatment regimen of 20.0% (15/75) of patients was impacted. The accuracy of the evaluation of the resectability of pancreatic cancer with 18F-FDG PET/MR was 91.9% (34/37). With the surgical and pathological results being used as a reference, the overall accuracy of preoperative 18F-FDG PET/MR for T staging was 62.2%, and the AUC for diagnosing T4 versus T1–3 was 0.872 (95% CI: 0.660–1.000). Conclusions: 18F-FDG PET/MR performs well in diagnosing advanced pancreatic cancer and thus may impact the treatment decisions for a considerable number of patients. 18F-FDG PET/MR has a high level of accuracy in evaluating the resectability of pancreatic cancer before surgery.

目的:探讨多排CT (MDCT)在鉴别胰腺实性型浆液性囊腺瘤(sSCA)与富血供神经内分泌肿瘤(pNET)中的价值.方法:回顾性分析2014年1月至2020年2月经上海交通大学医学院附属瑞金医院手术病理证实为胰腺sSCA(13例)及pNET(26例)的临床、上腹部CT资料.采用x2检验比较2组患者定性参数(性别、病灶部位、形态等),采用两独立样本t检验比较2组患者定量参数(病灶大小、平扫CT值、动脉期CT值等),对其中差异有统计学意义的定量参数绘制ROC曲线并比较曲线下面积(AUC)以评价其诊断效能.结果:sSCA (12/13)相较于pNET (13/26)平扫多呈相对低密度改变,sSCA平扫、门脉期CT值[(29.4±3.7)HU、(107.3±13.1) HU)]低于pNET[(43.6±6.5) HU、(123.4±18.4) HU],而动脉期、门脉期强化率[(4.1±1.3)×100％、(2.8±0.8) ×100％]均高于pNET[(2.9±0.9)×100％、(1.9±0.5)×100％],差异均有统计学意义(P＜0.05).ROC曲线显示平扫CT值所对应AUC (0.959)高于增强动脉期强化率(0.781)、门脉期CT值(0.750)、门脉期强化率(0.831),差异有统计学意义(P＜0.05),平扫CT值≤36.8 HU诊断sSCA的灵敏度、特异度分别为100％、92.3％.结论:胰腺sSCA与富血供pNET的CT表现常易混淆,平扫CT值对两者鉴别诊断具有较大价值.

目的:研究动态增强MRI定量与半定量参数在鉴别甲状腺结节良、恶性的临床价值.方法:收集2017-2020年在同济大学附属上海市第四人民医院接受甲状腺手术治疗,且术前均行动态增强MRI检查病例30例.共51个甲状腺结节入组,按病理结果分为良、恶性两组,良性结节35枚,恶性结节16枚.利用西门子后处理工作站对结节同一个感兴趣区域进行定量与半定量模型计算,定量指标包括容积转运常数(Ktrans)、速率常数(Kep)、血管外细胞外容积分数(Ve)、造影剂到达后60 s内曲线下初始面积(iAUC),半定量指标包括每分钟浓度流入增加量(wash-in)、每分钟浓度流出变化率(wash-out)、造影剂达到最大浓度时间(TTP)、造影剂到达时间(AT)、峰值增强强度(PEI)、iAUC.结果:恶性甲状腺结节组定量指标Ktrans、Kep、Ve、iAUC值明显小于良性甲状腺结节组(P＜0.05,其中Ktrans、iAUC值P＜0.001).恶性甲状腺结节组半定量指标wash-in、wash-out、PEI、iAUC值明显小于良性甲状腺结节组(P＜0.001);TTP与AT值在良恶性组之间差异无统计学意义.Ktrans、Kep、Ve、定量iAUC、wash-in、wash-out、PEI、半定量iAUC各指标单独鉴别甲状腺结节的曲线下面积分别为0.839、0.727、0.780、0.848、0.871、0.850、0.855、0.871.两个模型约登指数最高的分别是Ktrans(0.675)和wash-in (0.761),最佳诊断阈值为0.385、1.111.结论:动态增强MRI可应用定量指标Ktrans、iAUC和半定量指标wash-in、wash-out、PEI、iAUC对甲状腺结节的良、恶性进行鉴别诊断,其中Ktrans和wash-in的诊断效果更好.

目的:本研究应用能谱CT扫描成像,研究胰腺导管腺癌的能谱定量多参数,探讨胰腺导管腺癌CT能谱成像的参数特点及潜在应用价值.方法:回顾性分析经病理证实为胰腺导管腺癌,并均行胰腺能谱CT动脉晚期、门静脉期增强扫描的61例患者.记录胰腺癌病灶和胰腺实质的单能量CT值、有效原子序数(Effective-Z)、碘(水)基值、水(碘)基值.采用Wilcoxon符号秩和检验(非正态分布)或配对t检验(正态分布)比较胰腺癌和胰腺实质分别在动脉晚期和门静脉期间相应上述CT能谱成像参数的差异,并绘制相应能谱曲线.结果:动脉晚期胰腺导管腺癌单能量CT值明显低于周围正常胰腺,胰腺导管腺癌门静脉期单能量CT值高于动脉期,低于周围正常胰腺,差异在低能量段相当显著;胰腺导管腺癌与胰腺实质动静脉期能量段越低差异越明显,能量段越高,差异越小;胰腺导管腺癌与胰腺实质动静脉期的单能量CT值、配对基物质碘(水)基值、Effective-Z所对应均化浓度值有显著性差异,具有统计学意义,水(碘)值差异无统计学意义.结论:胰腺导管腺癌CT能谱成像的能谱参数具有一定特征.动静脉期胰腺癌单能量CT值、碘(水)基值、有效原子序数均低于相应胰腺实质,动脉晚期低于门静脉期,能量段越低差异越明显.综合应用多能量段和能谱多参数成像有助于提高能谱CT密度分辨力,具有为小胰腺癌早诊断提供影像信息的潜在价值.

目的 分析磁共振弥散加权成像(DWI)联合灌注加权成像(PWI)预测肿瘤样脑梗死最终梗死体积的价值.方法 回顾性分析31例经追踪磁共振成像(MRI)确诊的肿瘤样脑梗死患者的DWI和PWI,测量并计算梗死中心、预测误差区和缺血半暗带的相对脑血流量(rCBF)、相对脑血容量(rCBV)、相对平均通过时间(rMTT)和相对表观扩散系数(rADC),比较预测梗死中心体积与实际梗死中心体积的差异.结果 Tukey法事后功效检验显示,rCBF、rCBV在最终梗死、预测误差区、缺血半暗带间两两比较,差异均有统计学意义(P＜0.01),rADC在最终梗死与缺血半暗带间的差异有统计学意义(P＜0.01).PWI预测肿瘤样脑梗死不可逆损伤的敏感度高于DWI,其中rCBF的敏感度最高.追踪MRI显示出血转化(HT)和含铁血黄素沉着27例(87.10％).最终梗死体积均值为(20.8±11.9) cm3,小于预测梗死体积的(25.9±10.6) cm3,差异有统计学意义(t=7.682,P＜0.001).相关性检验显示最终梗死体积与预测梗死体积呈正相关(r=0.953,P＜0.001).结论 肿瘤样脑梗死的最终梗死体积小于预测梗死体积,原因可能与HT高发生率或再灌注有关.采用DWI和PWI多参数预测不可逆性损伤时,rCBF的敏感度最高.