功能MRI在儿童肾脏疾病诊断中的研究进展

儿童肾脏疾病可导致肾功能持续下降,需及时监测并控制其进展。目前,多种功能MRI（fMRI）技术已逐步用于儿童肾脏研究,不仅能明确肾脏结构有无异常,还可从肾脏水分子扩散、血氧水平等微观角度对肾功能进行评估,包括扩散加权成像（DWI）、扩散张量成像（DTI）、扩散张量纤维束示踪成像（DTT）、扩散峰度成像（DKI）、血氧水平依赖（BOLD）成像、MR灌注成像。介绍儿童肾脏的生理解剖特点,并综述fMRI在肾脏发育异常、慢性肾脏病、感染性病变、肿瘤性病变等多种疾病中的研究进展。     

扩散张量成像在孤独症谱系障碍中的研究进展

孤独症谱系障碍（ASD）是一类以社交、情感互动障碍,以及兴趣狭隘、行为刻板为基本特征的神经发育障碍性疾病。扩散张量成像（DTI）技术能够定量评价脑白质纤维束结构,可用于评价ASD病人全脑或特定白质纤维束结构的异常,也可用于分析ASD病人脑白质纤维束异常与临床症状、年龄及性别的相关性等。就DTI成像原理及其在ASD中的应用进展进行综述。     

产后抑郁症的MRI研究进展

产后抑郁症（PPD）为常见的产后精神障碍,其发病机制尚不清楚。基于体素的形态学分析、基于表面的形态学测量、扩散张量成像、扩散峰度成像、血氧水平依赖功能MRI、MR波谱成像等多种MRI技术已广泛用于探究PPD病人的脑结构、功能和代谢中发生的异常改变,这些技术使得明确PPD的神经生物学机制成为可能,也可为该病的早期诊断和预后判断提供客观的影像依据。就MRI在PPD中的影像学研究进展予以综述。     

慢性阻塞性肺疾病病人右心室功能改变的影像学研究进展

慢性阻塞性肺疾病（COPD）是临床常见的慢性呼吸系统疾病,常继发右心功能不全,增加病人死亡风险。COPD病人右心室功能改变的精准及多方式影像评价已成为研究的热点。超声心动图、CT、心脏MR成像、放射性核素等成像技术是目前无创性评价COPD右心室功能改变的主要方法。就COPD导致右心室功能改变的机制以及各种影像技术的应用进展及其优劣予以综述。     

RSNA2013中枢神经系统影像学

RSNA2013报道的拓展MRI新技术及数据分析方法主要包括体素内不相干运动（IVIM）扩散加权成像、VISIBLE序列磁共振三维成像、磁共振高分辨率血管壁成像（HRVW）、组织弹性成像（MRE）、磁敏感定量成像（QSM）、动脉自旋标记（ASL）、扩散峰度成像（DKI）等,在中枢神经系统疾病的应用研究主要包括：①鉴别胶质母细胞瘤复发和放射性坏死、判断肿瘤真性和假性进展;②早期检测卒中后锥体束Wallerian变性;③磁共振高分辨率血管壁成像观察颅内动脉粥样硬化血管壁的异常;④ASI。无创检测阿尔茨海默病的灌注异常、1HMRSGABA水平对阿尔茨海默病的早期监测;⑤QSM对帕金森病脑内铁沉积的定量;⑥糖尿病脑损伤的认知功能以及帕金森病运动功能的研究。     

精神分裂症脑白质成像研究进展

【摘要】少突胶质细胞及髓鞘形成异常对脑白质的完整性有极大影响,在精神分裂症的发病机制中发挥重要作用。同时,脑白质改变与认知功能损害的关联已被多项研究证实,而认知损害已被认为是精神分裂症具有特异性的核心症状。因此,通过神经影像学方法从精神分裂症患者中得到一系列在体的影像数据,用于定量研究髓鞘及脑白质在精神分裂症中结构和功能的变化情况,可以增加对精神分裂症病理机制的理解。本文对脑白质在精神分裂症中的相关机制及脑白质成像研究进行综述,涉及扩散张量成像（DTI）、扩散峰度成像（DKI）、磁化传递成像（MTI）及定量磁化率成像（QSM）技术等。     

脑小血管病相关认知障碍病人白质微结构异常的DTI研究进展

脑小血管病（CSVD）可引起病人的执行功能、注意力和信息处理速度等相关认知功能的减退,白质微结构的改变可能是CSVD相关认知减退的发病机制之一。扩散张量成像（DTI）目前已用于CSVD相关认知障碍的白质微结构异常的研究,能够观察微结构损伤情况、评估认知功能、评价脑网络变化等。介绍CSVD相关认知障碍白质微结构损伤的影响因素、机制,并综述DTI在CSVD相关认知障碍中的研究进展。     

糖尿病心肌病的CMR诊断及研究进展

心脏磁共振（CMR）成像技术具有多参数、多成像序列的特点,可以对糖尿病心肌病（DbCM）进行早期诊断,评价DbCM存在的心脏结构重塑、心脏整体和局部的收缩和舒张功能障碍、心肌灌注受损、心脏局部及弥漫性纤维化及心脏能量代谢和脂质异常,为病人的早期治疗及预后评估提供重要信息。就CMR对DbCM的心脏组织特征、风险评估和远期预后方面的诊断予以综述。     

高血压脑病发病机制及相关MRI表现

高血压脑病（hypertensive encephalopathy ,HE）是内科较为常见的急症,常发生在重症高血压患者,其发病机制目前较为公认的主要有血管痉挛学说和脑血管自动调节功能崩溃学说。M RI在高血压脑病诊断、鉴别诊断、疗效观察及预后评定中有重要帮助,以下主要通过 M RI不同成像技术方法,包括常规平扫、弥散加权成像、磁共振血管成像（MRA）、磁共振波谱成像（MRS）、磁共振增强扫描、磁共振灌注成像（PWI）及磁敏感成像（SWI）,综合起来阐述该病各有何种表现,就其相关临床发病机制予以综述。     

巴赫曼束（心耳间横肌束）及其动脉血供的多层螺旋CT成像对心房间传导异常和心律失常的提示

目的利用64层CT成像回顾性研究健康人和病人的巴赫曼束（BB）的解剖及其血供。方法本研究依从HIPAA法案并得到了机构审查委员会的批准可免除知情同意书。回顾317例病人（对照组164例，病人组153例）的临床病史、心电图（ECG）和64层CT冠状动脉成像影像。病人组中，房颤（AF）或房间传导阻滞（IAB）68例（P波持续时间≥120ms），严重冠状动脉疾病（CAD）46例[发出窦房结（SAN）动脉的冠状动脉狭窄程度≥70％]，严重CAD同时有心电图异常39例（AF或IAB）。对BB的长度、     

MR imaging findings in hepatic encephalopathy

The term hepatic encephalopathy (HE) includes a spectrum of neuropsychiatric abnormalities occurring in patients with liver dysfunction. Most cases are associated with cirrhosis and portal hypertension or portal-systemic shunts, but the condition can also be seen in patients with acute liver failure and, rarely, with portal-systemic bypass and no associated intrinsic hepatocellular disease. Although HE is a clinical condition, several neuroimaging techniques, particularly MR imaging, may eventually be useful for the diagnosis because they can identify and measure the consequences of central nervous system (CNS) increase in substances that under normal circumstances, are efficiently metabolized by the liver. Classic MR imaging abnormalities include high signal intensity in the globus pallidum on T1-weighted images, likely a reflection of increased tissue concentrations of manganese, and an elevated glutamine/glutamate peak coupled with decreased myo-inositol and choline signals on proton MR spectroscopy, representing disturbances in cell-volume homeostasis secondary to brain hyperammonemia. Recent data have shown that white matter abnormalities, also related to increased CNS ammonia concentration, can also be detected with several MR imaging techniques such as magnetization transfer ratio measurements, fast fluid-attenuated inversion recovery sequences, and diffusion-weighted images. All these MR imaging abnormalities, which return to normal with restoration of liver function, probably reflect the presence of mild diffuse brain edema, which seems to play an essential role in the pathogenesis of HE. It is likely that MR imaging will be increasingly used to evaluate the mechanisms involved in the pathogenesis of HE and to assess the effects of therapeutic measures focused on correcting brain edema in these patients.     

TIPSS术后肝性脊髓病（附5例报告）

目的：报告5例经颈静脉途径肝内分流术（TIPSS）后肝性脊髓病（HM）的临床表现。资料和方法：5例均有乙型肝炎和静脉曲张破裂出血病史。TIPSS术前影像学检查显示肝萎缩明显，术后分流道通畅。曾做脊髓MRI4例，1例做脊柱CT和脊髓造影。5例均行腰椎穿刺。结果：5例于TIPSS后4周－4个月出现进行性下肢痉挛性瘫痪，1例伴上肢无力，1例伴有尿失禁。5例术后有1次以上（1－6次）HE发作史。体验发现患者腱反射亢进，踝阵挛阳性，浅感觉正常，1例深感觉减退，除1例外，其余无明显肌莓缩表现。受累节段椎管影像学检查及腰椎穿刺脑脊液检查均无异常。5例均有术后持续高血低蛋白血症。结论：TIPSS术后出现进行性下肢痉挛性瘫痪、不伴有感觉障碍者应考虑HM。与TIPSS相关HM的高危因素有术前明显肝萎缩、术后持续高血氨及肝性脑病。     

Right ventricular function in patients after acute myocardial infarction assessed with phase contrast MR velocity mapping encoded in three directions

The purpose of the study was to assess global and regional myocardial function of the right ventricle (RV) with the use of phase contrast (PC) velocity mapping in patients after acute myocardial infarction. We examined 8 patients after acute myocardial wall infarction and 10 healthy volunteers for comparison. PC velocity mapping was performed in a single midventricular short-axis slice with velocity encoding in three different directions. RV displacement during systole in the through-plane direction differed significantly between patients and volunteers (P = 0.009). RV myocardial velocity in the through-plane and radial directions, evaluated at time of peak ejection rate, was significantly lower in patients than in healthy volunteers (P<0.05). RV abnormalities may be detected in patients after acute myocardial infarction using PC velocity mapping with velocity encoding in three different directions. Owing to their short acquisition times and relatively easy postprocessing, PC techniques are time-efficient and promising tools for the evaluation of RV function.     

PC机辅助MR脑灌注成像初步研究

目的:研究PC机辅助MR脑灌注成像软件,探讨其临床应用价值。方法:在PC机上使用MR脑灌注成像软件,对5例健康人和18例脑缺血患者的灌注图像进行后处理,计算出有关脑灌注参数图,包括相对脑血流量(rrCBF)图、相对脑血容量(rrCBV)图、局部灌注达峰时间(TTP)图和团注平均通过时间(bMTT)图。结果:应用MR脑灌注成像软件可以在PC机上实现灌注图像的后处理,脑灌注参数图能够为脑缺血患者提供有价值的脑血液动力学信息,显示灌注异常的范围。结论:PC机辅助MR脑灌注成像软件简单易行,可显示常规MR无法显示的血流动力学异常,对临床和科研具有重要价值。     

Abnormalities of CSF flow patterns in the cerebral aqueduct in treatment-resistant late-life depression: a potential biomarker of microvascular angiopathy.

There is growing evidence that microvascular angiopathy (MVA) plays an important role in the development of dementia and affective disorders in older people. At currently available image resolutions it is not possible to image directly the vascular changes associated with MVA, but the effects on blood and cerebrospinal fluid (CSF) flow may be detectable. The aim of this study was to investigate a potential biomarker for MVA based on MRI of abnormalities in CSF flow. Since there is considerable indirect evidence that treatment resistance in late-onset depressive disorder is related to MVA, we assessed the method in a group of 22 normal volunteers and 29 patients with responsive (N=21) or treatment-resistant (N=8) late-onset depressive disorder. Single-slice quantified phase-contrast (PC) images of cerebral blood and CSF flow were collected at 15 points over a cardiac cycle, and the resulting flow curves were parameterized. Significant differences in the CSF flow (width of systolic flow peak and diastolic flow volume, both P<0.01) through the cerebral aqueduct were observed for the group of treatment-resistant patients when compared to age matched controls. No significant difference was observed for a group of 21 patients with treatment-responsive depression. The findings support the hypothesis that MR measurement of CSF flow abnormalities provides a biomarker of MVA, and thus could have application in a wide range of age-related diseases.     

肺癌患者血清HE4的预后意义

目的 研究HE4在肺癌患者血清中的表达水平,探讨其在肺癌患者中的预后价值。方法 用酶联免疫吸附试验（ELISA）检测106例健康人及191例肺癌患者的治疗前血清HE4水平,检测各分期及不同病理类型肺癌患者HE4水平,并分析其与预后的关系。结果 肺癌组中位HE4水平91.63 pmol/L明显高于对照组56.42 pmol/L（U=3 081.00,P<0.05）;HE4的受试者工作特征（ROC）曲线下面积（AUC）为0.85,临界值（cut-off值）为82.70 pmol/L时,特异度为95.31%,灵敏度为62.32%。HE4表达与临床分期及病理类型无相关性;低HE4组（<91.63 pmol/L）患者的中位总生存期 （mOS）为36.87个月,高HE4组（≥91.63 pmol/L）患者的mOS为30.43个月（P<0.05）;HE4血清水平为判断肺癌患者预后的独立指标（HR=2.15,95%CI 1.49~3.12, P<0.05）。结论 血清HE4高表达肺癌患者预后较差,应接受积极的辅助治疗。     

Videofluoroscopy of swallowing abnormalities in 22 symptomatic patients after cardiovascular surgery

OBJECTIVE: The aim of this study was to evaluate the types of swallowing abnormalities that occur in symptomatic patients who have undergone cardiovascular surgery. MATERIALS AND METHODS: From 1994 to 2001, 22 patients (17 males and five females; age range, 4-89 years; mean age, 64 years) who had swallowing abnormalities after cardiovascular surgery were referred for a videofluoroscopic swallowing study. Each study was analyzed for functional abnormalities of the tongue, soft palate, epiglottis, hyoid and larynx, pharynx, upper esophageal sphincter, and esophagus. Also, the performance of transesophageal echocardiography, long-term intubation, or both was noted. RESULTS: Swallowing abnormalities were present in 18 patients (81.8%) (range, one to eight functional abnormalities; mean, 3.9 functional abnormalities). The distribution of abnormalities across the functional units statistically significantly deviated (chi(2) = 14.4; df = 6; p = 0.025) from uniform distribution, with abnormalities most commonly involving the hyoid and larynx (13 patients [59.1%]) and the pharynx (10 patients [45.5%]). Aspiration was found in 13 patients (59.1%) (predeglutitive, n = 1; intradeglutitive, n = 4; postdeglutitive, n = 3; and mixed, n = 5). In the 14 patients (63.6%) who underwent transesophageal echocardiography, long-term intubation, or both, we frequently found incomplete tilting of the epiglottis, pharyngeal weakness, and postdeglutitive aspiration. CONCLUSION: Most patients with swallowing problems after cardiovascular surgery present with multiple abnormalities that most commonly affect the hyoid and larynx and the pharynx and result predominantly in intra- or postdeglutitive aspiration. The performance of transesophageal echocardiography and long-term intubation may influence the types of swallowing abnormalities.     

The effect of education on rCBF changes in Alzheimer’s disease: a longitudinal SPECT study

Purpose  To determine the relationship of differing levels of education on regional cerebral blood flow (rCBF) in patients with Alzheimer’s disease (AD). Methods  Fifty-three patients with AD followed-up for an average of 36 months were divided into the high-educated group (HE, ≥12 years of schooling) and low-educated group (LE, <12 years of schooling). The cognitive and functional impairment was assessed using the Mini-Mental State Examination (MMSE) and the Functional Assessment Staging (FAST), respectively. Initial and follow-up rCBF were assessed using SPECT with N-isopropyl-p-[¹²³I]-iodoamphetamine and the SPECT data were analyzed by 3D-stereotactic surface projections. Results  At initial evaluation, the HE group had greater rCBF deficits in the parietotemporal regions than did the LE group, even though both groups had comparable MMSE and FAST scores. When compared with initial SPECT, follow-up SPECT showed a significant rCBF reduction in widespread regions, including the frontal, parietal, temporal, and limbic lobes of the HE group, while it a significant rCBF reduction in scattered and small regions of the parietotemporal, cingulate, and occipital areas of the LE group, as the HE group had faster cognitive and functional decline than the LE group. Conclusion  The HE group showed lower rCBF at initial SPECT than the LE group, suggesting more advanced AD pathology. As a result, the HE group demonstrated a more extensive and severe reduction of rCBF on follow-up SPECT in association with faster cognitive and functional decline than the LE group. Our SPECT study provides stronger support for the cognitive reserve effects of education in AD.     

evaluation of communication between intracranial arachnoid cysts and cisterns with phase-contrast cine MR imaging

BACKGROUND AND PURPOSE: The demonstration of communication between arachnoid cysts (ACs) and the adjacent subarachnoid space is a prerequisite for their proper management. CT cisternography (CTC) is the conventional method for functional evaluation of ACs. The sensitivity of MR imaging to CSF flow has been demonstrated, but reports of the clinical usefulness of MR CSF flow techniques in this application are limited. The purpose of our study was to prospectively evaluate the accuracy of MR CSF flow study as an alternative to CTC in this setting. METHODS: MR CSF flow study with retrospective ECG-gated 2D, fast low-angle shot, phase-contrast (PC), cine gradient-echo sequence was performed in 39 patients with an intracranial AC. Results were compared with intraoperative and CTC findings. RESULTS: PC cine MR imaging results were compatible with operative or CTC findings in 36 (92.3%) of 39 patients. Twenty-four cysts were noncommunicating, and 15 were communicating. Three cysts were evaluated as being noncommunicating on PC cine MR imaging (false-negative) but demonstrated contrast enhancement on CTC. No false-positive diagnoses occurred. All cysts regarded as being communicating on PC cine MR imaging were also found to be communicating on both confirmation methods. CONCLUSION: MR CSF flow imaging with a PC cine sequence can be incorporated in the imaging work-up of ACs. This is a reliable alternative to invasive CTC for the functional evaluation of ACs.     

Phase-contrast MR angiography of intracranial dural arteriovenous fistulae

MRI and phase-contrast MR angiography (PC MRA) were obtained in 13 patients with angiographically confirmed intracranial dural arteriovenous fistulae (DAVF). Three- and two-dimensional PC MRA was obtained with low (6–20 cm/s) and high (> 40 cm/s) velocity encoding along the three main body axes. MRI showed focal or diffuse signal abnormalities in the brain parenchyma in six patients, dilated cortical veins in seven, venous pouches in four with type IV DAVF and enlargement of the superior ophthalmic vein in three patients with DAVF of the cavernous sinus. However, it showed none of the fistula sites and did not allow reliable identification of feeding arteries. 3D PC MRA enabled identification of the fistula and enlarged feeding arteries in six cases each. Stenosis or occlusion of the dural sinuses was detected in six of eight cases on 3D PC MRA with low velocity encoding. In six patients with type II DAVF phase reconstruction of 2D PC MRA demonstrated flow reversal in the dural sinuses or superior ophthalmic vein. Received: 14 May 1998 Accepted: 15 December 1998