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951.
目的 探究对比MRI-LAVA序列与增强CT诊断对肝脏结节性病变的应用价值.方法 选取78例肝脏结节性病变患者均接受MRI-LAVA序列诊断以及增强CT诊断,比较诊断的准确率、灵敏度、特异度以及准确度.结果 在病理学诊断结果中,共诊断出91处病灶,其中直径不低于3 cm的病灶共有24处,直径低于3 cm的病灶共有67处...  相似文献   
952.
目的:基于循环一致性生成对抗网络(CycleGAN),利用非配对患者盆腔部位数据,实现MRI和CT图像之间的相互转换,并对基于该模型生成的盆腔伪CT(sCT)进行精度和剂量性能的评估。方法:该CycleGAN网络包含两个生成器和两个判别器。先基于全卷积网络(FCNs)构建两个生成器,一个将2D盆腔MRI转换为2D盆腔sCT图像,另一个将CT图像转换为伪MRI(sMRI)图像。再基于FCNs构建两个判别器,用于对真实图像和生成的伪图像进行判别,提升生成图像的质量。为保证sCT图像与MRI图像的一致性,引入归一化互信息作为相似性约束损失项,对模型进行改进。训练集包括35例患者盆腔部位的T1-MRI图像和另外36例患者盆腔部位的CT图像,测试集包括10例盆腔部位患者的MRI和CT图像,评估方法包括sCT与CT图像的误差和放疗剂量伽马通过率。结果:对于测试集中所有病例,生成的sCT与真实CT图像之间的平均绝对误差(MAE)为35.537(±4.537) HU;基于体素的平均剂量差异最大为0.49%;以3%/3 mm、2%/2 mm和1%/1 mm为标准的平均伽马通过率分别高于99%、98%和95%。结论:使用CycleGAN网络和非配对患者训练数据可以生成准确且符合临床剂量精度要求的盆腔部位sCT图像。  相似文献   
953.
目的探讨脑静脉及静脉窦血栓形成(CVST)累及的结构及影像学特征。方法回顾性分析152例经临床及影像检查确诊为CVST患者的临床资料,观察CVST累及的结构,分析其影像学特征。结果152例CVST中,最常受累的静脉结构为横窦(57.2%),其次为上矢状窦(51.9%)、乙状窦(48%)、颈内静脉(12.5%),超过50%的CVST累及多个静脉窦,皮质静脉及深静脉血栓少见;上矢状窦血栓以中段血栓最为常见。39.5%的患者存在脑实质损害,最为常见的是脑水肿或脑肿胀,其次是静脉性脑梗死、颅内出血等;CVST最为常见的CT影像学特征依次是高密度三角征、条带征,而高密度点征、火焰征少见;MRI的特征性表现为静脉血管腔血液流空效应消失;DSA表现为静脉窦腔狭窄、显影变淡或完全不显影,侧支静脉异常扩张。结论CVST主要累及横窦及上矢状窦中段,常同时阻塞多个静脉窦;常见的直接影像学特征有条带征、三角征及血管充盈缺损;间接影像征象有脑水肿、脑出血、静脉性脑梗死等。了解脑静脉及静脉窦的结构及CVST影像学特征对CVST的早期诊断具有重要意义。  相似文献   
954.
We report on three cases of cystic neoplasms of the liver with mucinous epithelium. Case 1 showed a low-grade cystic neoplasm with ovarian-like stroma (OS). Case 2 showed a low-grade cystic neoplasm without OS, and case 3 showed a high-grade cystic neoplasm without OS. In all three cases, bile duct communication (BDC) was absent. Currently, pancreatic mucinous cystic neoplasm (MCN) and intraductal papillary mucinous neoplasm of the pancreas (IPMN) are clearly distinguishable. However, MCN of the liver and intraductal papillary neoplasm of the bile duct (IPN-B) are not as easily distinguished. According to the latest WHO classification (2010), these conditions are classed as typical MCN of the liver, MCNs of the liver without OS, or IPN-Bs without BDC. The clinicopathological differences between MCN without OS and IPN-B without BDC are controversial. We present three cases describing these presentations and discuss the difficulties related to the diagnostic criteria used to distinguish between MCN of the liver and IPN-B.  相似文献   
955.
The paternal uniparental disomy 14 is a rare malformation syndrome whose postnatal pathognomonic sign is the deformation of the rib as coat hanger. In prenatal, ultrasonographic signs are major recurrent polyhydramnios, a narrow thorax and deformed long bones short and sometimes other anomalies including ends. The authors report one rare case of prenatal paternal uniparental disomy 14 with the deformation of the rib as coat hanger. Prenatally, the narrow deformed thorax can be searched by ultrasound three-dimensional (3D) and/or helical CT and thus represent an aid to prenatal diagnosis.  相似文献   
956.

Objectives

The purpose of this review is to summarize literature pertaining to clinical roles of positron emission tomography (PET) or integrated PET and computed tomography (PET/CT) scans, magnetic resonance imaging (MRI) and emerging techniques of these two molecular imaging tools for gynecologic malignancies.

Methods

PubMed and MEDLINE databases search for articles published before June 2014 was performed. Only English-language articles were considered. Search terms included “cervical cancer”, “endometrial cancer”, “uterine cancer”, “uterine sarcoma”, “ovarian cancer” and “vulvar cancer”, in association with “FDG”, “PET”, “PET/CT”, “MRI”, “PET/MR”, “diffusion”, “spectroscopy” and “clinical trial”.

Results

Topics explored included PET, PET/CT and MRI for diagnosis of malignancy, prognostic implications, clinical staging of disease extent, monitoring treatment response, post-therapy surveillance, diagnosis of treatment failure and restaging, and follow-up after salvage therapy in gynecologic malignancies.

Conclusions

Molecular imaging (mainly PET and MRI) plays important roles in the management of gynecologic malignancies. Molecular imaging has various impacts in different clinical scenarios. Emerging technologies will continuously improve our practice. Prospective studies with defined endpoints are necessary to evaluate roles of these novel tools in management of gynecologic malignancies.  相似文献   
957.
目的 探究胃癌螺旋CT影像学表现与临床分析关系相关研究.方法 选择2018年7月~2019年9月64例胃癌患者为研究对象,均对其实施多层螺旋CT检查并进行分析,将其与术后病理分期进行比较.结果 以手术病理检查分期为标准,多层螺旋CT检查轴位结合多平面重建(MPR),在胃癌T分期中,T1、T2、T3、T4及总准确率分别为...  相似文献   
958.
To evaluate the chest computed tomography (CT) findings of patients with Corona Virus Disease 2019 (COVID-19) on admission to hospital. And then correlate CT pulmonary infiltrates involvement with the findings of emphysema. We analyzed the different infiltrates of COVID-19 pneumonia using emphysema as the grade of pneumonia. We applied open-source assisted software (3D Slicer) to model the lungs and lesions of 66 patients with COVID-19, which were retrospectively included. we divided the 66 COVID-19 patients into the following two groups: (A) 12 patients with less than 10% emphysema in the low-attenuation area less than −950 Hounsfield units (%LAA-950), (B) 54 patients with greater than or equal to 10% emphysema in %LAA-950. Imaging findings were assessed retrospectively by two authors and then pulmonary infiltrates and emphysema volumes were measured on CT using 3D Slicer software. Differences between pulmonary infiltrates, emphysema, Collapsed, affected of patients with CT findings were assessed by Kruskal–Wallis and Wilcoxon test, respectively. Statistical significance was set at p < 0.05. The left lung (A) affected left lung 20.00/affected right lung 18.50, (B) affected left lung 13.00/affected right lung 11.50 was most frequently involved region in COVID-19. In addition, collapsed left lung, (A) collapsed left lung 4.95/collapsed right lung 4.65, (B) collapsed left lung 3.65/collapsed right lung 3.15 was also more severe than the right one. There were significant differences between the Group A and Group B in terms of the percentage of CT involvement in each lung region (p < 0.05), except for the inflated affected total lung (p = 0.152). The median percentage of collapsed left lung in the Group A was 20.00 (14.00–30.00), right lung was 18.50 (13.00–30.25) and the total was 19.00 (13.00–30.00), while the median percentage of collapsed left lung in the Group B was 13.00 (10.00–14.75), right lung was 11.50 (10.00–15.00) and the total was 12.50 (10.00–15.00). The percentage of affected left lung is an independent predictor of emphysema in COVID-19 patients. We need to focus on the left lung of the patient as it is more affected. The people with lower levels of emphysema may have more collapsed segments. The more collapsed segments may lead to more serious clinical feature.  相似文献   
959.
目的 分析双排螺旋 CT 联合 X 线平片用于腰椎间盘突出症的诊断效果和应用价值。方法 收集 40 例腰椎间盘突出症手术患者,行双排螺旋 CT、X 线平片检查,分析两种检查方法的影像学特征,并以手术病理结果为标准,比较单一检查、联合检查的符合率。结果 以手术结果为标准,腰椎间盘突出单一 X 线平片检查符合率为 47.5%;单一双排螺旋 CT检查符合率为 90%;X 线平片联合 CT 检查符合率为 100%。联合检查与单一 X 线平片检查、单一 CT 检查比较差异均有统计学意义(P<0.05)。双排螺旋 CT 腰椎间盘突出症诊断分型符合率为 95%,与手术病理结果比较差异无统计学意义(P>0.05)。X 线平片提示,腰椎间隙宽度和长度明显异常,腰椎生理弯曲,呈弓状、后翘状态。CT 检查提示,椎体边缘可见椎间盘突出,密度稍低于椎间盘,小关节突增生,结节不规则,侧隐窝狭窄,突出块较大时,可见软组织密度影,硬膜囊、神经根表现为变形、移位,甚至消失。结论 X 线平片、CT 检查在腰椎间盘突出症诊断中各具优势,但若单一检查,容易发生误诊、漏诊等不良事件,两者联合诊断,可有效提高诊断符合率,为临床治疗提供可靠的影像学依据,具有重要的研究价值。  相似文献   
960.
CT和MRI能区分附件良恶性包块、炎性包块,但MRI更有优势。文章讨论了附件包块分类;常见卵巢良、恶性肿瘤及炎性包块的影像学特点和鉴别要点;CT和MRI在卵巢恶性肿瘤分期、附件扭转中的重要诊断价值。期待借助于CT和MRI,为附件包块的诊治提供精准的支持。  相似文献   
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