CT and MR imaging of chemotherapy-induced hepatopathy

Abdominal Radiology - Chemotherapy-induced hepatopathy includes a wide variety of parenchymal and vascular hepatic changes on imaging, including diffuse or focal hepatopathies (i.e. hepatitis,...     

Retroperitoneal bronchogenic cyst: CT and MR imaging

Retroperitoneal bronchogenic cysts are extremely rare congenital anomalies that represent malformations of the embryonic foregut and are morphologically expressed as maldevelopments of the respiratory system. Because of the low prevalence of these tumors, their imaging features have seldom been described. We present the computed tomographic and magnetic resonance imaging findings of a case of retroperitoneal bronchogenic cyst.     

Contrast-enhanced CT and MR imaging of renal vessels

In the evaluation of renal vessels, the accepted diagnostic gold standard digital subtraction angiography is now being challenged by state of the art CT and MR imaging. Currently in many centers, cross-sectional imaging modalities are being used as a first line diagnostic tool to evaluate arterial and venous system of the kidneys and conventional angiography has been reserved only for therapeutic intervention. CT and MR imaging display not only the lumen of the vessel as in conventional angiography, but also allow the visualization of the vessel wall, renal parenchyma, collecting system, and other adjacent soft tissue structures. Therefore, CT and MRI have each become a one-stop shop for a thorough evaluation of kidneys. In this pictorial essay, we reviewed normal anatomical variants and wide range of pathologies involving renal arteries and veins with illustrated contrast-enhanced CT and MR imaging samples.     

颅内血管母细胞瘤的CT及MRI影像分析

目的提高对颅内血管母细胞瘤的CT及MRI影像特征的认识.方法收集经手术病理证实的颅内血管母细胞瘤46例.所有病例均做了MRI检查,其中26例同时做了CT检查.结果 46例54个肿瘤,囊腔型42个,典型表现为囊腔大、结节小及结节显著异常强化;实质型12个,肿瘤信号强度在T2WI明显升高,增强后显著强化,瘤内或瘤周可见血管流空信号.结论 CT和MRI是诊断血管母细胞瘤的有效方法,尤其是MRI的多轴位成像及增强扫描可避免肿瘤及壁结节的漏检.     

Multidetector row CT and MR imaging in diagnosing hepatocellular carcinoma

It is important to diagnose hepatocellular carcinoma (HCC) correctly and in early stage, because viral hepatitis and liver cirrhosis are often complicated by HCC. Noncontrast and enhanced CT and MRI are very useful to visualize and diagnose HCC objectively. Especially, CT and MR imaging with dynamic study is essential to diagnose HCC, because it is usually hypervascular. Dynamic CT and MR study also improve differential diagnosis in the characterization of the tumor. However, to perform useful dynamic study, it is necessary to use a CT unit which can make a helical scan, or a MR system with fast imaging technique available that can obtain more than 15 slices within a single breath hold. Tissue specific contrast medium, such as superparamagnetic iron oxide that is available only on MRI, is also useful for diagnosis of HCC.     

非酮症性高血糖偏侧舞蹈症脑部CT及MRI表现

目的分析非酮症性高血糖偏侧舞蹈症患者脑部CT及MRI影像学特点。方法回顾性分析11例经临床确诊的非酮症性高血糖偏身舞蹈症患者的脑部CT及MRI表现。11例患者均接受至少一次CT及MRI平扫,其中2例行MRI增强检查,4例加做DWI序列,6例加做MRS序列,2例加做DTI序列,3例复查MRI平扫,1例复查CT平扫。结果 9例CT见豆状核和/或尾状核头部片状高密度影,2例CT阴性;T_1WI 9例高信号,2例阴性;DWI 2例高低混杂信号,1例低信号,1例阴性;MRS检查:NAA峰6例均降低,Cho峰6例均升高,NAA/Cr比值6例均降低,Cho/Cr比值6例均升高;DTI 1例显示左侧内囊前肢纤维束受损,FA值减低,1例阴性。结论非酮症性高血糖偏侧舞蹈症脑部CT及MRI均具有特征性影像表现,DWI、MRS及DTI等序列对确定病变性质、评估神经元丢失或损伤、纤维束受损等有价值。     

颅底软骨瘤的CT与MRI表现

目的：探讨CT与MRI对颅底软骨瘤的影像诊断价值。方法：12例中，9例行MR平扫及增强扫描，7例行CT平扫，其中3例做增强扫描，4例同时行CT及MR检查，结果：12例软骨瘤均位于颅底中线旁硬膜外，鞍旁肿瘤呈类圆形；同时累及前中颅凹或中后颅凹的肿瘤呈“哑铃”形或不规则形，肿瘤边缘清楚，5例有颅底骨质破坏，其余病例肿块周围骨质呈侵蚀性改变，CT上肿瘤呈等，高混杂密度6例，呈均匀稍高密度1例，钙化表现为斑块状，小球状及弧线样高密度，MRI上T1WI均为低信号，7例肿块T2WI为高，低混杂信号，其余2例T2WI为均匀高信号，6例肿瘤外侧与脑实质之间T2WI上可见弧线样低信号线，冠状位MRI上可见海绵窦有不同程度受累，CT与MR增强扫描肿瘤为不均匀强化，结论：颅底软骨瘤多位于中线旁的硬膜外，特别是鞍旁，前颅凹或后颅凹肿块相连，根据其部位及CT、MRI表现可以做出诊断。     

恶性卵巢子宫内膜样肿瘤的影像学评价

目的探讨恶性卵巢子宫内膜样肿瘤的CT及MRI诊断价值。方法回顾性分析10例经手术病理证实的恶性卵巢子宫内膜样肿瘤的cT或MRI表现。结果10例恶性卵巢子宫内膜样肿瘤13个肿块．7例为单侧（左侧4例,右侧3例）,3例为双侧（左右各一）。10例中卵巢子宫内膜样腺癌7例;恶性Maller混合瘤2例（1例为双侧,1例合并子宫内膜腺癌）;卵巢子宫内膜样间质肉瘤合并子宫内膜异位症1例。平扫示肿瘤多为类圆形、分叶状实性为主肿块,囊变多见,增强扫描后肿瘤实性部分不均匀强化,部分病例边缘明显强化,呈多囊状环形强化6例。结论恶性卵巢子宫内膜样肿瘤的影像表现具有一定特征性,CT和／或MR可明确定性,对病理诊断有一定的提示作用。     

冠状动脉易损斑块CT及MR成像进展

易损斑块破裂或侵蚀导致继发血栓形成是急性冠状动脉综合征的主要发病机制。传统影像学手段关注引起管腔严重狭窄的冠状动脉斑块,而忽略了对易损斑块的显示。随着对粥样斑块病理生理学认识的深入,冠状动脉管壁成像及识别易损斑块成为研究热点。基于无创影像学技术识别斑块成分及形态特征、进而评估斑块易损性,有助于临床识别高危患者,预测及预防未来心血管事件,具有重大临床应用价值。     

Nonangiographic imaging of the pulmonary arteries: CT and MR

Computed tomography (CT) has provided a imaging modality by which the central pulmonary arteries can be studied noninvasively. CT provides cross-sectional images which accurately depict the pulmonary arteries and adjacent structures. Magnetic resonance (MR) imaging with its ability to image vessels without contrast media provides a potential truly noninvasive means of examining the pulmonary arteries. These modalities are well suited to evaluate pathology involving the central pulmonary arteries. Normal CT and MR anatomy is illustrated and discussed. The clinical presentation and appearance of pathological processes involving the pulmonary arteries are described.     

Imaging of the liver by helical CT and MR imaging

With modern imaging technologies, including helical CT and MR imaging, the evaluation of liver morphology, blood flow and detection and characterization of liver neoplasms is possible in a noninvasive manner. Experiences in numerous institutions have established that both imaging methods are highly accurate in diagnosing hepatic pathology. Three-dimensional evaluation is feasible with fast imaging techniques such as multislice CT. With tissue-specific MR contrast agents such as SPIO, our capability is enhanced not only with respect to lesion detection but also lesion characterization.     

动脉瘤样骨囊肿CT与MRI征象分析

目的 探讨CT与MRI对动脉瘤样骨囊肿（ABC）的诊断价值。方法 回顾性分析43例经手术病理证实的动脉瘤样骨囊肿的影像表现，全部病例均行X线检查，其中14例行CT检查，19例行MRI检查，10例同时行CT及MRI检查。结果 在X线上ABC表现为膨胀性骨质破坏。在CT上动脉瘤样骨囊肿表现为溶骨性骨质破坏，常有不同程度膨胀性改变，骨质破坏区内可见囊状低密度区及骨性分隔，MRI表现为T1WI及T2WI上可见病灶边缘有低信号环，病灶内主体部分充满囊状液体，信号混杂，在T1WI低或中高信号，在T2WI上呈不均匀高信号，病灶内可见T1WI及T2WI上均呈低信号的分隔。Gd-DTPA增强扫描后可见囊壁及病灶内的分隔强化。结论 CT与MRI对动脉瘤样骨囊肿诊断与鉴别诊断有非常重要的价值。     

多层螺旋CT与MRI 对胰头癌的诊断价值比较

目的用统计学方法比较多层螺旋CT与MRI在胰头癌诊断与鉴别诊断中的价值。方法顺序抽取2002年9月-2005年3月间经手术病理证实为壶腹周围病变,且在术前一周之内经本院多层螺旋CT与MRI检查的病例共62例,包括胰头癌27例,壶腹癌25例,胆总管下段癌4例,胰头炎症与胆总管下段结石各3例。将62例病例分为胰头癌组(27例)和非胰头癌组(35例),由两位放射科医师独立进行阅片,其结果分别进行Kappa一致性检验和ROC曲线分析。结果①两位医师判读结果经Kappa一致性检验,Kappa值分别为0.828和0.894,P>0.05,无显著性差异,说明两位医师具有良好的一致性。②取其中一位医师的CT与MRI判读结果进行ROC曲线分析,Az值分别为0.880与0.863。结论由于多层螺旋CT可以进行多期扫描,以及各种重建技术,大大提高了其对胰头癌诊断的准确性,其与MRI互相补充,可以进一步提高诊断准确性。     

Comparison of MR imaging and CT in the evaluation of renal masses

The present status of magnetic resonance imaging (MRI) in the evaluation of renal masses, especially as compared to computed tomography (CT) is discussed based on our experience and on a review of the literature. It is already apparent that simple renal cysts, hemorrhagic cysts, and fatty renal masses are well demonstrated by MRI. However, other modalities, and particularly CT, have similar degrees of accuracy, are more widely available, and are less expensive. So, currently, MRI has not been proven to be an optional screening method for detection of renal masses. At present, the major clinical uses of MRI are (1) the staging of renal carcinoma, in which MRI appears slightly superior to CT, (2) in patients with known contraindications to the use of iodinated contrast medium, (3) in patients with suspected renal carcinomas in which results from other imaging modalities are atypical or indeterminate, and (4) when sagittal or coronal imaging is desirable.     

CT myocardial perfusion imaging: current status and future perspectives

Computed tomography myocardial perfusion (CTP) combined with coronary computed tomography angiography (CCTA) may constitute a “1-stop shop” for the noninvasive diagnosis of hemodynamically significant coronary stenosis during a single CT examination. CTP shows high diagnostic performance and provides incremental value over CCTA for the detection of hemodynamically significant coronary stenosis in patients with a high Agatston calcium score or coronary artery stents. Future studies should determine the optimal protocol and clinical value of CTP for guiding revascularization strategy and prognostication. In this article, we review the current status and future perspectives of CTP, focusing on technical considerations, clinical applications, and future research topics.     

CT灌注成像联合磁共振扩散加权成像诊断急性脑梗死

目的 探讨联合应用CT灌注成像(CTPI)和MR DWI技术对急性脑梗死的临床诊断价值。 方法 对38例临床怀疑急性脑梗死的患者进行脑CTPI联合DWI检查,扫描结束后,经CT灌注软件和Funtiontool软件进行评估,统计各参数值。 结果 梗死脑区与对侧脑区比较,脑灌注(Perfusion)、强化峰值(PE)、达峰时间(TTP)、ADC值差异均有统计学意义(P均<0.05), 脑血容量(CBV)差异无统计学意义(P>0.05);相对灌注值(rP)与相对CBV值(rCBV)具有显著相关性(r=0.721,P＜0.05);rCBV与相对ADC值(rADC)具有相关性(r=0.476,P＜0.05)。 结论 CTPI各参数中,以TTP值和PE值的变化能最敏感地反映出急性梗死时血流动力学变化。rCBV与rADC共同反映梗死脑区的病理变化特征,具有本质上的相关性。     

Autoimmune hepatitis: CT and MR imaging features with histopathological correlation

Background  

To describe the CT and MRI features of autoimmune hepatitis (AIH) and correlate them with histological grade and stage. Observed changes associated with treatment are also described.     

儿童腹盆腔横纹肌肉瘤的CT与MR影像学分析

目的:探讨儿童腹盆腔横纹肌肉瘤(RMS)的CT与MR影像学特征.方法:对经手术病理证实的10例腹盆腔RMS患儿的CT与MR影像资料进行总结分析.其中行CT平扫10例,增强扫描6例;行MR平扫3例,增强扫描3例.结果:CT平扫均见腹盆腔内较大软组织肿物,密度欠均匀,部分有坏死区,邻近组织受压推移甚至侵犯、淋巴结及远处转移;增强后病灶不均匀轻中度强化,以周边强化明显,动脉期病灶内可见较多增粗、扭曲的供血动脉影,延迟期斑片状持续性强化.MR检查T1WI序列示腹盆腔内等低混杂信号巨大肿物,T2WI序列上以稍高信号为主;增强后呈不均匀持续性强化.结论:儿童腹盆腔RMS是一种少见的间充质源性恶性肿瘤,CT与MR影像学表现能为其诊断及鉴别提供有用的信息.     

肝脓肿的CT表现及Mm扩散成像分析

肝脓肿可由细菌、寄生虫或霉菌引起，是临床常见疾病，明确诊断对制定合理的治疗方法具有重要意义。CT对肝脓肿的诊断高度敏感，但肝脓肿CT表现多样，而且近年来。MRI扩散加权成像在肝脏疾病中的应用已逐渐被大家认同，故本文拟通过CT表现与MRI扩散加权成像ADC值相结合的方法，探讨肝脓肿的影像学特点，提高诊断准确率。