产后子痫并可逆性后部白质脑病综合征的MR分析

目的 探讨产后子痫并可逆性后部白质脑病综合征的MR影像.表现特点.方法 对16例经过临床和颅脑MR扫描确诊的产后子痫并可逆性后部白质脑病综合征进行回顾性分析.16例均行常规MR平扫(T1Flair、T2WI、TF2Lair及DWI),8例同时进行了MRV扫描,9例治疗后进行二次MR平扫复查.结果 MR显示:病灶位于双侧性顶、枕叶12例、单侧顶枕叶1例、额叶2例、基底节区5例,DWI多数病例表现为等或相对低信号,MRV均提示无血栓形成.9例二次MR平扫复查示明显吸收好转或基本吸收.结论 产后子痫并可逆性后部白质脑病综合征好发于顶枕叶,少数见于额叶,基底节区,T2 WI和T2Flair较为敏感.     

Spectrum of radiological changes in hypertensive children with reversible posterior leucoencephalopathy

We prospectively studied 19 children with severe hypertension to evaluate the spectrum of radiological changes, severity and reversibility of this entity. All of them were subjected to clinical and biochemical evaluation, followed by magnetic resonance imaging (MRI) and magnetic resonance angiography (MRA). Headache was seen in 17 children, 13 had confusion and drowsiness, 12 had nausea and vomiting, 10 patients had visual disturbances, seizure and dyspnoea. Only two had focal neurological deficit (one with right facial palsy and another with right lateral rectus palsy). Of these 19 children, 15 patients had hypertensive retinopathy and four had normal fundi. The positive MRI findings in 17/19 patients were: bilateral leukoencephalopathic changes in occipitoparietal region (9/17), diffuse white/grey matter lesion (3/17) patients, brain stem hyperintensity (2/17) and haemorrhagic lesions (3/17). On MRA, 12/19 patients had attenuation of cerebral arteries of different degree. On follow up, MRI findings resolved in all except three patients. All patients had normal MRA on follow up, except one with persistent minimal attenuation of middle cerebral artery and another had spasm in anterior, middle and posterior cerebral arteries. The intracranial abnormalities in these patients with severe hypertension were reversible in many of the cases after control of blood pressure was achieved. We therefore conclude that severe hypertension may lead to leuoencephalopathy, which had a wide radiological spectrum. A better understanding of this complex syndrome may obviate unnecessary investigations and allow management of associated problems in prompt and appropriate ways.     

Cerebral hyperperfusion in a patient with eclampsia with perfusion-weighted magnetic resonance imaging

The patient was a 25-year-old Japanese woman with postpartum eclampsia, in whom magnetic resonance imaging (MRI) was performed ten hours after convulsion. The patient improved within three days. Diffusion-weighted images showed a high apparent diffusion coefficient (ADC), and perfusion-weighted images obtained by the multi-slice flow-sensitive alternating inversion recovery (FAIR) method showed hyperperfusion, which was suggestive of vasogenic edema, on the parietal and occipital subcortical white matter, corresponding with transient hyperintensities on T2-weighted images. MR angiography (MRA) revealed no signs of vasospasm. These findings suggested hyperperfusion-induced vasogenic edema without cerebrovascular spastic change in the early stage of eclampsia. The FAIR method is considered a useful technique for perfusion-weighted MRI, especially useful to evaluate the cerebral perfusion of emergency patients such as those with eclampsia.     

子痫前期及子痫所致可逆性后部白质脑病综合征影像表现与临床分析

目的：探讨子痫前期及子痫所致可逆性后部白质脑病综合征（reversible posterior leukoenphalopathy syn-drome ,RPLS ）影像学表现与临床特点。方法回顾性分析我院2009年8月～2011年12月8例子痫前期及子痫患者致可逆性后部白质脑病综合征影像表现与临床资料。结果 RPLS影像学病灶分布,顶枕叶8例,颞叶4例,额叶6例,丘脑1例,基底节1例,CT表现两侧顶枕叶区斑片状的低密度区,灰白质界限模糊,脑回样对称分布,可伴有额叶、颞叶部位脑白质低密度影,灰质一般不受累,MRI表现为T1WI等或低信号,T2WI高信号,FLAIR序列呈高信号,DWI呈等或高信号,ADC呈高信号影,临床表现癫痫发作5例,头痛4例,意识障碍5例,视物模糊1例,高血压8例,所有患者经治疗症状消失,无后遗症。结论认识RPLS特有的影像表现,结合子痫前期及子痫临床特点能得出正确诊断。     

MRI和MRV在评价先兆子痫、子痫后脑静脉窦闭塞和可逆性后部脑白质病的价值

目的 探讨MR静脉成像（MRV）和MRI对孕产妇特有疾病先兆子痫、子痫的脑部并发症——静脉窦闭塞和可逆性后部脑白质病（PRES）的诊断价值。方法 回顾性分析27例妊娠期间或产后出现癫痫、头痛、视物模糊的先兆子痫、子痫病人的临床及影像学资料,其中6例为顺产后3～5d,4例为剖宫产后1d,5例为妊娠25～34周胎死宫内,12例为足月妊娠。病人均行MRI和MRV检查,检查序列包括：T,WI、T2WI、FLAIR、DWI。结果 14例显示静脉窦闭塞,其中上矢状窦4例,以前部为主。横窦2例、乙状窦1例、深部静脉系统2例、颈内静脉3例、皮质静脉3例。全部静脉窦闭塞2例。MRI显示相应闭塞静脉的引流区呈不规则形长T1、长T2信号影,DWI显示等信号,ADC图呈高信号。4例病人出现DWI高信号,ADC图呈低信号,提示病变为细胞毒性水肿。5例2周后随访MRI及MRV显示静脉窦通畅,而2例并发了脑实质出血。13例PRES病人,MRI显示双侧顶叶（10例）、右侧顶叶（2例）、双侧枕叶（7例）、双侧额叶（6例）、右侧额叶（3例）、双侧颞叶（4例）、左侧颞枕叶交界区（1例）、胼胝体压部（1例）、双侧基底节区（2例）、右侧基底节区（1例）、左侧半卵圆中心（1例）、双侧小脑半球（1例）多发异常信号。病变于T1WI呈等或低信号,T2WI及FLAIR呈高信号,部分病灶DWI及ADC图均表现为高信号。1例病人左侧颞叶发生出血。6例随访MRI显示病灶范围变小,数目减少,甚至病灶消失。结论 静脉窦闭塞好发于上矢状窦,但深静脉和浅静脉均可发生。PRES好发于顶枕叶白质,皮质也可受累。还可见于额叶、基底节区、颞叶、胼胝体、小脑半球。两者病变均为血管源性水肿．但分布的部位和范围不同．MRI和MRV对其可作出明确诊断。     

MRI和MRV在评价先兆子痫、子痫后脑静脉窦闭塞和可逆性后部脑白质病的价值

目的 探讨MR静脉成像(MRV)和MRI对孕产妇特有疾病先兆子痫、子痫的脑部并发症--静脉窦闭塞和可逆性后部脑白质病(PRES)的诊断价值.方法 回顾性分析27例妊娠期间或产后出现癫癎、头痛、视物模糊的先兆子痫、子痫病人的临床及影像学资料.其中6例为顺产后3～5 d,4例为剖宫产后1 d,5例为妊娠25～34周胎死宫内,12例为足月妊娠.病人均行MRI和MRV检查,检查序列包括:T1WI、T2WI、FLAIR、DWI.结果 14例显示静脉窦闭塞,其中上矢状窦4例,以前部为主.横窦2例、乙状窦1例、深部静脉系统2例、颈内静脉3例、皮质静脉3例.全部静脉窦闭塞2例.MRI显示相应闭塞静脉的引流区呈不规则形长T1、长T2信号影,DWI显示等信号,ADC图呈高信号.4例病人出现DWI高信号,ADC图呈低信号.提示病变为细胞毒性水肿.5例2周后随访MRI及MRV显示静脉窦通畅,而2例并发了脑实质出血.13例PRES病人,MRI显示双侧顶叶(10例)、右侧顶叶(2例)、双侧枕叶(7例)、双侧额叶(6例)、右侧额叶(3例)、双侧颞叶(4例)、左侧颞枕叶交界区(1例)、胼胝体压部(1例)、双侧基底节区(2例)、右侧基底节区(1例)、左侧半卵圆中心(1例)、双侧小脑半球(1例)多发异常信号.病变于T1WI呈等或低信号,T2WI及FLAIR呈高信号,部分病灶DWI及ADC图均表现为高信号.1例病人左侧颞叶发生出血.6例随访MRI显示病灶范围变小,数目减少,甚至病灶消失.结论 静脉窦闭塞好发于上矢状窦,但深静脉和浅静脉均可发生.PRES好发于顶枕叶白质,皮质也可受累,还可见于额叶、基底节区、颞叶、胼胝体、小脑半球.两者病变均为血管源性水肿.但分布的部位和范围不同,MRI和MRV对其可作出明确诊断.     

Posterior reversible encephalopathy syndrome with atypical regions in eclamptic patients: A challenge for radiologists

Purposes

To determine the distribution and incidence of atypical regions of involvement of PRES in eclapmtic patients by using MR imaging.

Material and methods

A prospective study was approved by the ethical committee of our institution during the period between October 2011 and March 2012. Twenty two registered eclamptic patients (age ranged from 20–38 years; average 29 years) who had clinical signs and symptoms of PRES were recruited in the study, all patients were referred from Gynecology and Obstetric department, for brain MRI to evaluate PRES after clinical suspicion. All images were reviewed for the presence of high signal intensity on FLAIR and T2WI, for the severity of the vasogenic brain edema, on the basis of the extent of hyperintensity on FLAIR imaging. DWI was also interpreted for the presence or absence of areas of restricted diffusion corresponding to the hyperintensity areas on T2WI and FLAIR images.

Results

The most common clinical presentations were seizures, and altered mental status seen in 11 patients (50%). Other clinical presentations included headache (4 [18.1%]), visual disturbance in one patient and loss of consciousness in one patient. Most commonly involved location was the parieto-occipital brain region, which was seen in 19 (86.3%) of the (22) patients. This was followed by the frontal lobe in 13 patients (59%), the temporal lobe in 3 (13.6%), Basal Ganglia in 3 patients and cerebellum in 3 patients, 11 (50%) had subcortical involvement of white matter edema and 9 (40.9%) had cortical involvement. Lesions were asymmetric in nearly half of the cases (n = 10[45.5%]), unilateral in 3 patients. Restricted diffusion was present in 9 patients (40.9%), and no hemorrhage was present in all patients. As regarding severity of edema in FLAIR, half of patients had moderate edema (n = 11) while only 2 patients had severe edema and 9 had mild edema.

Conclusion

PRES can affect anterior circulation structures and atypical regions fairly frequent than commonly known. However, a posterior predominance is certainly seen in each lobe. Atypical regions of involvement represents a challenge for radiologist and necessitate strict clinical correlation and follow up.     

可逆性后部脑病综合征的不典型影像学表现

目的:研究可逆性后部脑病综合征(PRES)的不典型影像学表现并进一步探讨其可能的发病机制。方法:回顾性分析了57例PRES患者的临床和影像学资料,其中17例行钆喷替酸葡甲胺(Gd-DTPA)增强扫描,35例患者行CT平扫。由2位神经放射医生共同评价不典型影像学异常(脑出血、弥散受限、异常强化),比较脑水肿累及不同部位之间差异。结果:脑水肿顶、枕叶的累及与其他各部位相比均有统计学显著性差异(P0.05)。弥散受限所致的高信号10例(占17.5%),其中4例发生脑梗死(占7.0%);5例发生颅内出血(占8.8%);17例患者行增强扫描10例出现异常强化(占58.8%)。结论:正确认识PRES不典型表现对PRES的早期诊断具有重要意义,有利于进一步探讨PRES的发病机制及病理生理学改变。     

Intracranial hypertension with reversible cerebral edema: Atypical presentation of neuropsychiatric systemic lupus erythematosus

We described in this article a 19-year-old girl with an intracranial hypertension as an initial presentation of neuropsychiatric lupus. The brain MRI showed diffuse, bilateral and symmetrical white and grey matter hyperintensities. These lesions completely disappeared after 3 months of treatment. Diffuse cerebral edema with or without leukoencephalopathy in neuropsychiatric systemic lupus erythematosus is an extremely rare entity.     

Posterior reversible encephalopathy syndrome: a possible late interaction between cytotoxic agents and general anaesthesia

A 49-year-old woman who had previously received treatment with cytotoxic drugs for metastatic gestational trophoblastic disease (GTD) presented with a witnessed tonic–clonic seizure, headache, confusion and blindness, 6 days after the uneventful administration of a general anaesthetic and 2 months after cessation of chemotherapy. Magnetic resonance imaging showed relatively symmetrical, subcortical, white matter abnormalities, predominantly affecting the occipital, posterior temporal and parietal lobes and the cerebellum. T2-dependent abnormalities and elevated regional apparent diffusion coefficient were present in a pattern typical for posterior reversible encephalopathy syndrome (PRES). The clinical and radiological manifestations were resolved completely with supportive therapy. This case of PRES may be a late complication of gemcitabine or cisplatin therapy precipitated by a general anaesthetic, or associated electrolyte or blood pressure disturbance.     

Corpus callosum infarcts with atypical clinical and radiologic presentations

Infarcts of the corpus callosum have not been well documented in the radiologic literature. We present five cases that were unusual in either their clinical or radiologic presentation or both. Biopsies were performed in three of the five cases, and in time, all lesions evolved in a pattern consistent with infarct. Recognition of the varied clinical and radiologic presentation of infarcts of the corpus callosum will obviate the need for biopsy in most patients.     

采用优化的基于体素的形态测量学方法研究不同类型智力障碍患儿脑灰质容积的变化

目的 利用优化的基于体素的脑形态学分析法(VBM),分别比较以操作缺陷为主和以语言缺陷为主的智力障碍患儿与正常儿童脑灰质容积的差异,探究患儿脑区灰质发育与操作和语言缺陷之间的联系.方法 选取9例以操作缺陷为主(操作缺陷组)和11例以语言缺陷为主(语言缺陷组)的智力障碍患儿,以及分别与之性别、年龄及优势利手相匹配的正常对照组儿童11、14名,行三维快速扰相梯度回波(FSPGR)序列高分辨率脑MR扫描,然后采用VBM方法进行图像分析.采用独立样本t检验比较操作缺陷组和语言缺陷组与相应正常对照组间灰质总容积差异以及不同区域脑灰质容量差异.结果 操作缺陷组患儿脑灰质容积总量平均值[(1.030 ±0.078)×106 mm3]明显大于正常对照组[(0.984±0.058) ×106 mm3],差异有统计学意义(t=-2.6,P＜0.05);患儿脑局部区域灰质容积较正常对照组高的脑区包括:后扣带回、右侧额上回、左侧楔叶、左侧额中回和左侧尾状核体部.语言缺陷组患儿脑灰质容积总量[(1.002±0.068)×106 mm3]明显大于正常对照组[(0.957±0.057) ×106mm3],差异有统计学意义(t=-3.0,P＜0.05);患儿脑局部区域灰质容积较正常对照组高的脑区包括:双侧丘脑、左侧颞下回、左侧额下回和左侧小脑.结论 VBM能够显示常规MRI表现正常的智力障碍患儿中的脑灰质发育异常.不同临床表型的智力障碍患儿脑灰质容积改变区域分布存在差异.     

脑后部可逆性脑病综合征的CT、MRI诊断

目的探讨CT、MRI在诊断脑后部可逆性脑病综合征（PRES）中的价值。方法8例女性PRES患者中6例为孕妇，1例肺癌手术后化疗患者，1例高血压患者，均行MR静脉成像（MRV）、T1WI、T2WI、水抑制序列（FLAIR）成像及扩散加权成像（DWI）；其中2例行CT平扫，5例行增强MRI及三维增强MR血管成像（3DCEMRA）。结果CT示病灶呈低密度，边界不清。8例患者MRV显示脑静脉、静脉窦通畅，无狭窄、异常扩张及血栓形成征象。MRI显示双侧顶枕叶（8例）、基底节区（2例）、额叶（4例）多发异常信号，主要位于双侧顶枕叶皮质下白质内，3例患者皮质亦受累。在T1WI病灶呈等或略低信号，T1WI及FLAIR呈高信号，以FLAIR像显示皮质病变为佳。DWI显示大部分病灶呈等信号，表观扩散系数（ADC）图呈等或高信号。部分病灶DWI及ADC图均表现为高信号。随访MRI显示所有患者病灶范围、数目逐渐变小、减少。5例行增强扫描患者显示病灶呈轻度强化，3D CEMRA显示强化沿双侧大脑前动脉、大脑中动脉及大脑后动脉终末支分布，部分呈“葡萄状”。随访增强扫描显示病灶强化范围及程度逐渐缩小、消失。结论FRES好发于顶枕叶白质，但也可见于基底节、额叶及脑皮质。病变为血管源性水肿，增强T1WI及3D CEMRA显示病灶有可逆性强化。以MRFLAIR及T2WI序列显示病灶最佳。     

慢性脑缺血患者脑血流动力学与脑代谢改变的影像学研究

目的 探讨慢性脑缺血患者影像学特点,评价其脑血流动力学与脑代谢之间的相关性.方法 对55例临床拟诊为慢性脑缺血的患者行常规头颅CT平扫和CT灌注(CTP)检查.以CTP图为参考,对出现脑灌注异常患者共43例行单体素质子磁共振波谱(1H-MRS)检查.测量灌注异常区与对侧脑组织血流动力学和代谢参数,分析两者之间的相关性.结果 55例慢性脑缺血患者中有43例发现脑灌注异常,CTP及1H-MRS显示病变侧平均通过时间(MTT)、达峰时间(TTP)较对侧明显延长,氮-乙酰天门冬氨酸∕肌酸(NAA/Cr)、氮-乙酰天门冬氨酸∕胆碱(NAA/Cho)较对侧降低,差异均有统计学意义(P＜0.01);脑血容量(CBV)、胆碱∕肌酸(Cho/Cr)高于对侧镜像区,差异有统计学意义(P＜0.05);脑血流量(CBF)较对侧略低,差异无统计学意义(P＞0.05);另外12例未见灌注异常.灌注异常区NAA/Cho与MTT、TTP均呈负相关(P＜0.01).结论 慢性脑缺血患者存在脑血流动力学和脑代谢的异常,脑代谢异常可在一定程度上反映脑血流动力学损害情况.     

Giant angiomyolipoma with atypical arteriovenous shunting: CT and angiographic studies

The advent of both ultrasound and computerized tomography made the pre-operative diagnosis of angiomyolipoma much easier. However, differentiation from retroperitoneal, perinephric space and especially intrarenal liposarcoma remains difficult or impossible. Angiographic findings are atypical and often do not allow differentiation from renal cell carcinoma. Early filling of the renal vein in renal cell carcinoma is sometimes used to distinguish renal cell carcinoma from angiomyolipoma. A case of a giant angiomyolipoma with arteriovenous shunting and early filling of the renal vein is described.