肝血管平滑肌脂肪瘤的CT、MRI表现

目的探讨肝血管平滑肌脂肪瘤(HAML)的影像学特征,提高对HAML的术前诊断水平。方法回顾性收集并分析经手术病理证实的7例HAML患者的临床及影像学资料,分析患者临床特点,包括年龄、性别、发病症状、肿瘤标记物、肝背景情况;分析病灶在CT和/或磁共振成像(MRI)的基本影像表现,包括数量、大小、部位、脂肪成分、强化方式、供血动脉、肿瘤内血管。结果 7例HAML患者均为女性,年龄28~53岁,平均年龄43.8±8.2岁。7例中除1例发生于肝硬化基础上,其余均见于正常肝背景。5例为上皮样HAML,2例为非上皮样HAML。4例只行双期增强CT检查,1例只行MRI平扫及增强检查,2例同时行增强CT及MR检查。4例在CT或MRI可见脂肪成分,在CT上表现为明显低密度区,CT值约为(负43-负49HU);在MRI上表现为瘤内勾边效应。6例表现为"快进快出"强化方式,1例表现为动脉期高强化及延迟强化。5例可见增粗的肿瘤供血动脉,4例可见肿瘤内网状、扭曲走行的血管影。结论 CT或MRI发现肿瘤内脂肪成分有助于术前明确诊断HAML。对于无脂肪成分肿块,需结合临床病史及穿刺活检确诊。     

肝血管平滑肌脂肪瘤超声造影、增强CT特点及其与病理分型的关系

目的比较肝血管平滑肌脂肪瘤（HAML）超声造影与增强CT增强模式差异,并探讨其与病理分型的关系。方法回顾性分析2006年1月至2012年12月第三军医大学西南医院30例经手术或者穿刺确诊为HAML患者超声造影及增强CT术前诊断结果及影像学表现,并与其病理学检查结果进行对照分析。本组病灶超声造影典型表现的比例与增强CT典型表现的比例采用Fisher确切概率法进行比较。结果本组30例HAML患者共31个病灶,17个病灶常规超声表现为不均质高回声;20个病灶超声造影表现为3个时相不均匀强化的HAML典型超声造影表现,余11个病灶超声造影增强模式不典型。17个病灶CT平扫示瘤内含有脂肪密度;7个病灶增强CT表现为3个时相不均匀强化的典型增强CT表现;余24个病灶增强模式不典型。31个病灶超声造影显示典型表现的比例（64．5％）高于增强CT（22．6％）,且差异有统计学意义（JP量0．002）。11个混合型HAML病灶中,7个病灶超声造影表现典型增强模式,2个呈典型增强CT表现;10个平滑肌细胞为主型HAML病灶中,6个病灶超声造影表现典型增强模式,2个呈典型增强CT表现;8个成熟脂肪细胞为主型HAML病灶中,6个病灶超声造影表现典型增强模式,3个呈典型增强CT表现。结论常规超声联合超声造影能够显示多数HAML的回声和血流灌注特点,且HAML的超声造影与增强CT表现与病理分型有关。     

磁共振扩散加权成像量化诊断肝脏局灶性病变的研究进展

肝脏局灶性病变(focal liver lesion,FLL)的检出和定性是影像学研究的重要内容,动态增强CT、CT经动脉门脉成像、肝动脉增强CT和增强MR是重要的检查手段并相互补充。磁共振扩散加权成像(diffusion weighted imaging,DWI)是一种功能成     

CT与磁共振成像诊断儿童中枢神经系统神经母细胞瘤的价值

目的:分析CT与磁共振成像诊断儿童中枢神经系统神经母细胞瘤的价值。方法:选取2016年9月～2018年11月进行检查的48例高度疑似中枢神经系统神经母细胞瘤患儿为研究对象,均行CT及磁共振成像检查。以病理组织学检查结果为金标准,比较CT、磁共振成像诊断中枢神经系统神经母细胞瘤的应用价值,并分析中枢神经系统神经母细胞瘤的影像学特点。结果:病理学检查确诊43例患儿为中枢神经系统神经母细胞瘤,磁共振成像诊断疾病的灵敏度、准确度均高于CT,差异有统计学意义(P0.05);两种检查方法的特异度、阳性预测值、阴性预测值比较,差异无统计学意义(P0.05)。CT检查中枢神经系统神经母细胞瘤可见病灶呈囊实性,实性部分呈等密度,囊性部分密度低,可见小条状高密度钙化影,受压顶骨部分压迹边缘光滑。MRI检查可见桥脑处存在病灶,且已呈现肿胀,肿胀大小为4 cm×3 cm×3 cm,对肿胀处进行扫描可知病灶以实性为主,T1WI序列为低信号,T2WI序列为高信号,FLAIR序列为等信号,MRI增强扫描未见强化病灶及病灶周围组织水肿。结论:CT及与磁共振成像在儿童中枢神经系统神经母细胞瘤的影像学表现具有一定特征,磁共振成像的诊断价值高于CT,但临床诊治仍需行病理检查。     

肝脏血管平滑肌脂肪瘤的多层螺旋CT表现特征及其病理学基础

目的探讨肝脏血管平滑肌脂肪瘤（hepatic angiomyolipoma,HAML）的多层螺旋CT影像学表现特征及其与病理学基础的相关性,以进一步提高CT诊断的准确性。方法收集2008年11月2010年12月经手术病理证实的16例HAML患者。所有患者均行螺旋CT平扫及动脉期、门脉期增强检查,重点观察HAML的分型及其相应CT表现及影像-病理的相关性。结果 16例患者共20个病灶,19个为稍低密度病灶,其中11个病灶内可见明显的脂肪密度影;1个为稍高密度病灶。动脉期所有病灶均有不同程度的强化表现,15个病灶内可见到较明显条状及扭曲的血管影。门脉期15个病灶有持续强化。结论多层螺旋CT能准确反映HAML的分型及其病理特征,对临床表现不典型患者的诊断和鉴别诊断有较大诊断价值。     

动态增强磁共振成像在经CT扫描良恶性难以定性的肺结节诊断中的应用价值

目的：分析动态增强磁共振成像对经CT扫描良恶性难以定性诊断的肺结节患者的价值。方法：选取2019年11月~2020年11月收治的肺结节患者100例,均经CT检查难以定性,行动态增强磁共振成像检查,以术后病理检查为金标准,分析动态增强磁共振成像检查良恶性病变最大强化值及最大相对强化比,并比较动态增强磁共振成像检查与CT检查肺结节良恶性定性准确率。结果：恶性病变最大强化值高于良性病变,最大相对强化比低于良性病变（P＜0.05）;动态增强磁共振成像诊断恶性病变准确率较CT检查高（P＜0.05）。结论：动态增强磁共振成像检查应用于CT检查难以定性的肺结节患者,可明显提高良恶性鉴别准确率,对临床提供更多参考信息,同时最大强化值及最大相对强化比对良恶性鉴别具有一定作用。     

骨质疏松骨折应用SPECT/CT的临床诊断价值和影像学特征探析

目的:关于骨质疏松骨折采取SPECT/CT进行诊断的应用价值以及影像学特征进行探讨。方法:选取2019年1月到2020年1月接诊的骨质疏松骨折病患50例作为本次研究对象,给予50例骨质疏松骨折病患磁共振成像和SPECT/CT检查,比较骨质疏松骨折病患接受两种不同诊断方式的诊断结果。结果:SPECT/CT和磁共振成像对于新鲜骨折以及陈旧性骨折的判断方面存在一致性。结论:对于骨质疏松骨折病患骨折定位和定性诊断方面,应用SPECT/CT能够获得与磁共振成像相同的临床诊断效果,并且SPECT/CT诊断存在独特技术优势,能够成为磁共振成像诊断替代,在大多数骨骼病变诊断中获得广泛的推广与应用。     

股骨颈疝窝的磁共振弥散加权成像

背景：目前利用磁共振弥散成像反映股骨颈疝窝的水分子弥散特征的研究尚少有报道。目的：利用磁共振表观弥散系数定量测定对股骨颈疝窝和正常股骨颈进行鉴别,探讨股骨颈疝窝的弥散系数值、影像学表现和发病机制。方法：收集18例经病理证实或具有典型影像学征象的股骨颈疝窝影像学患者的资料,全部患者均行X射线平片、CT、常规磁共振成像和弥散加权成像检查。依据CT和常规磁共振成像上异常表现,行股骨颈疝窝弥散系数测量,并与正常股骨颈弥散系数值进行比较。结果与结论：18例患者共20个病灶,均位于股骨头基底和股骨颈前外侧皮质下,形态呈圆形、卵圆形或分叶状。X射线平片上表现为伴清晰薄层硬化缘的透亮区,CT上表现为伴锐利的薄层硬化缘的骨质缺损区,磁共振成像上T1WI为低信号,T2WI为高信号。股骨颈疝窝的表观弥散系数值明显高于正常股骨颈。结果提示,弥散加权成像为股骨颈疝窝的诊断提供有价值的信息,证实股骨颈疝窝的弥散增加和弥散系数值升高。     

磁共振成像在肺结节的研究进展

肺结节在临床上为常见病变,一般多为X线、CT检查时偶然发现,传统的影像学检查方法各有优势,但随着影像新技术的发展,比如MSCT、LDCT、数字化断层融合技术、CT灌注成像、PET-CT、能谱CT、增强CT扫描等检查技术的出现,临床对于肺结节的检出及随访不再局限,同时提高了肺结节的检出率以及良恶性结节的鉴别诊断。磁共振作为近年来迅速发展的影像检查技术,因其多序列多参数成像、无辐射及较低的假阳性率被广泛应用于临床检查。本文就磁共振成像检查技术对孤立性肺结节的研究进展进行综述。     

肝血管平滑肌脂肪瘤超声及CT影像学对比分析

目的探讨肝血管平滑肌脂肪瘤（HAML）的影像学表现及其与病理组织学相关性。方法回顾性分析我院近3年经病理诊断的6例11灶HAML患者的常规超声、超声造影及CT表现，并对照病理组织学进行分析。结果6例HAML中脂瘤型2例，肌瘤型1例，混合型3例。脂瘤型、肌瘤型、混合型3种类型超声表现分别为高回声、低回声及混合回声，相应CT平扫表现为含脂肪成分的极低密度影、软组织密度影及混杂密度影。3例行超声造影检查动脉期均有不均匀或均匀强化，2例脂瘤型延迟期仍稍高于周围肝实质，1例混合型有轻度退出。增强CT（CECT）所有病灶动脉期均有不均匀或均匀强化，门脉期4例（脂瘤型2例，混合型2例）高于周围肝实质，2例（肌瘤型1例，混合型1例）低于周围肝实质。超声诊断良性2例，恶性1例，性质不确定3例；CT诊断良性3例，性质不确定3例。结论因脂肪组织、平滑肌及血管3种成分比例及分布不同，HAML影像学表现呈多样性，超声造影及增强CT有助于良恶性诊断，但部分病例仍难以除外恶性，确诊须依据肝穿刺活检或术后病理检查。     

Hepatic angiomyolipoma: CT and MR imaging findings with clinical–pathologic comparison

Objective

The objective of this study is to evaluate the clinical, pathologic, and computed tomography (CT) and/or magnetic resonance imaging (MRI) findings of hepatic angiomyolipoma (HAML) and to improve the diagnostic efficacy of the tumor.

Materials and methods

Clinical, pathologic, and imaging findings were retrospectively evaluated in 18 patients with HAML. Two patients underwent both CT and MRI, ten underwent CT alone, and six underwent MRI alone. Unenhanced and contrast-enhanced examinations were performed in all patients. Imaging characteristics, such as the lesion location, lesion diameter, presence of early draining veins, attenuation/signal intensity of the lesions on imaging, and enhancement pattern were reviewed.

Results

There were 3 male and 15 female patients. HAML was seen as a well-defined, solitary mass on imaging with medium size (mean diameter, 5.9 cm). Fat was detected in ten patients. Calcification was noted in two patients and cystic degeneration was seen in one patient. Hepatic cirrhosis and capsule were not detected in all patients. The mean attenuation values exceeded 120 hounsfield units (HU) in 11 patients (91.7%). Peripherally decreasing enhancement rim as well as early draining vein was seen in 15 patients (83.3%). The early draining veins were all hepatic veins. Tumor vessels were noted in all patients.

Conclusion

The presence of early draining vein, peripheral decreasing enhancement rim, and the absence of tumor capsule in the hypervascular hepatic tumor on CT and/or MRI together with normal alpha fetal protein may be helpful for the diagnosis of HAML in non-cirrhotic liver.     

MCT、MRI诊断急性胰腺炎价值比较

目的探讨MCT与MRI影像检查对急性胰腺炎（包括急性胆源性胰腺炎）的诊断价值,为急性胰腺炎的影像学诊断提供依据。方法对2005年1月至2007年12月本院住院的164例急性胰腺炎（包括急性胆源性胰腺炎）患者的MCT及MRI检查结果进行综合对比分析。结果MRI对急性胰腺炎诊断的阳性率为89％,MCT的阳性率为88．4％,二者比较差异无显著性（P〉0．05）;MRI（MRCP）对急性胆源性胰腺炎诊断的阳性率为72．4％,MCT的阳性率为53．1％,二者比较差异无显著性（P〉0．05）。结论MCT及MRI均对急性胰腺炎的诊断有重要意义,但MRI（MRCP）对急性胰腺炎病因的诊断价值较高。     

Application of new imaging techniques for the evaluation of squamous cell carcinoma of the head and neck

The past several years have seen dramatic changes in imaging of the head and neck. Technical improvements in CT and MRI coupled with their widespread availability have made cross-sectional imaging an important adjunct in evaluation of patients with disease of the extracranial head and neck. The most recent advances in head and neck imaging are from new metabolic and functional imaging techniques. The intent of this report is to provide an update on the potential role of positron emission tomography, new MRI agents, and magnetic resonance spectroscopy for evaluating squamous cell carcinoma of the extracranial head and neck.     

Magnetic resonance imaging and proton magnetic resonance spectroscopy of intracranial epidermoid tumors

Intracranial epidermoid tumors or cysts are considered benign lesions. Differentiation of epidermoid tumors from arachnoid cysts is important for appropriate patient care because the treatment is different for each lesion. Arachnoid cysts can appear very similar to epidermoid tumors on computed tomography (CT). Epidermoid tumors can grow in the cerebellopontine angle (CPA) cistern, the most common location of these lesions, resulting in trigeminal neuralgia and facial paralysis. Treatment for epidermoid tumors is exclusively surgery. Arachnoid cyst, on the other hand, is a benign condition that rarely produces symptoms. Recent advances in magnetic resonance imaging (MRI) have allowed more accurate imaging diagnosis of epidermoid tumors. This article reviews the recent advances in MRI using conventional T1W, post-contrast T1W, T2W, steady-state free precession imaging, fluid-attenuated inversion recovery (FLAIR), diffusion-weighted imaging (DWI), and proton magnetic resonance spectroscopy (MRS) in the imaging diagnosis of epidermoid tumors.     

放射性核素骨显像在人工关节置换后假体松动与感染鉴别诊断中的作用

背景：假体松动和感染是人工关节置换失败的常见原因,因此两者的鉴别非常重要。因大多患者无典型的临床表现,其他实验室检查的确诊方法也非常有限。目前,放射性核素骨显像与CT、磁共振成像及X射线检查已成为诊断假体松动和感染的常用方法,但何种方法能更有效地检查出病变,一直存在争论。目的：分析人工关节置换后假体松动和感染的放射性核素骨显像与CT、磁共振成像及X射线诊断的相关文献,对这些检查方法进行优选,为临床治疗方案的选择和预后的判断提供根据。方法：收集人工关节置换后假体松动和感染患者的放射性核素骨显像与CT、磁共振成像及X射线诊断的相关文献,对其影像学表现进行回顾性分析,比较几种影像学诊断方法的优缺点。结果与结论：人工关节置换后假体松动和感染的临床表现不容易区分,而且假体松动的早期尚未形成假体周围骨骼结构异常或假体周围较细小的透亮带被遮挡等,常影响X射线或者CT诊断,所以诊断时常出现误诊、漏诊。另外关节假体多为金属材料,CT或磁共振成像会出现伪影,也影响对假体松动和感染的判断。放射性核素骨显像可更准确的对人工关节置换后假体松动和感染的患者定位、定性诊断,对预后有更重要的临床价值。     

Current and future perspectives in imaging of venous thromboembolism

Summary

Several thrombus imaging techniques for the diagnosis of venous thromboembolism (VTE) are available. The most prevalent forms of VTE are deep vein thrombosis of the lower extremities and pulmonary embolism. However, VTE may also occur at unusual sites such as deep veins of the upper extremity and the splanchnic and cerebral veins. Currently, the imaging techniques most widely used in clinical practice are compression ultrasonography and computed tomography (CT) pulmonary angiography. Moreover, single‐photon emission CT, CT venography, positron emission tomography, and different magnetic resonance imaging (MRI) techniques, including magnetic resonance direct thrombus imaging, have been evaluated in clinical studies. This review provides an overview of the technique, diagnostic accuracy and potential pitfalls of these established and emerging imaging modalities for the different sites of venous thromboembolism.     

Neuroimaging in acute stroke

This article reviews the various imaging modalities available for the evaluation of patients presenting with a potential stroke syndrome, specifically acute ischemic stroke, intracerebral hemorrhage, and subarachnoid hemorrhage. It reviews the various computed tomography (CT) modalities, including noncontrast brain CT (NCCT), CT angiography, and CT perfusion. It discusses multimodal magnetic resonance imaging in the evaluation of patients with acute stroke, including diffusion-weighted imaging, T2-weighted sequences/fluid-attenuated inversion recovery, magnetic resonance angiography, perfusion-weighted imaging, and gradient-recalled echo. At the end of this article, a brief review on how to read an NCCT geared toward the emergency physician is included.