儿童白质消融性脑白质病的MRI表现

目的 探讨白质消融性脑白质病(VWM)的MRI特征表现.方法 回顾性分析2008年至2013年间经本院儿科基因确诊为VWM的10例患儿的临床及MR资料.由2名资深的神经放射医师进行阅片,对白质病变部位(大脑、小脑、脑干、胼胝体及内外囊)、范围、信号特点、有无囊变、脑萎缩及基底节受累等进行分析.结果 10例大脑中央白质均弥漫受累,9例部分皮层下白质受累,7例伴U形纤维受累;7例伴有囊变;8例内囊后肢受累,7例外囊受累,8例胼胝体内缘(透明隔缘)受累.2例丘脑和苍白球出现异常信号,6例脑干白质受累,7例小脑白质受累.结论 大脑中央白质出现弥漫对称的异常信号伴囊变是VWM特征性的MRI表现,对该病的诊断具有重要价值.     

MRI对原发性中枢神经系统淋巴瘤的诊断

目的 探讨原发性中枢神经系统淋巴瘤(primary central nervous system lymphoma,PCNSL)的MRI特点,提高对PCNSL的认识和诊断水平.方法 回顾性分析21例经手术病理或穿刺活检证实的PCNSL的MR表现,并结合文献研究MRI特征.结果 单发7例,多发7例,弥漫性生长7例,共33个肿瘤,其中额叶12个,脑室旁8个,颞叶、顶叶、透明隔、小脑蚓部各2个,枕叶、基底节区、丘脑、脑干、小脑各1个; 4例肿瘤累及胼胝体.肿瘤实质MR T1WI呈等或稍低信号,T2WI呈等或稍高信号,信号较均匀;18例肿瘤实质强化明显,信号均匀,可呈现"尖角征"和"脐凹征"及具有特征性的"蝴蝶征",3例出现环形强化.结论 PCNSL MR检查具有特征性表现,MRI检查对PCNSL具有独特的诊断价值.     

儿童异染性脑白质营养不良的MRI表现

目的 观察异染性脑白质营养不良（MLD）的特征性表现。方法 回顾分析我院经生化检查证实的MLD共11例,观察MRI上脑内白质病变的部位和特殊结构（白质纤维束、丘脑、胼胝体）受累的情况。结果 11例均表现为双侧脑室周围白质T2WI对称高信号,10例双侧半卵圆中心T2WI对称高信号;4例累及皮层下白质。8例累及胼胝体膝部,9例累及压部,两者同时受累为8例;7例累及内囊后肢,4例累及外囊,4例累及脑干皮质脊髓束（3例中脑,1例桥脑）。1例累及小脑白质,8例半卵圆中心T2WI有虎纹征,8例T2WI丘脑呈低信号;5例侧脑室扩大,1例全脑萎缩。结论 MLD的典型表现为双侧半卵圆中心和侧脑室周围白质T2WI对称高信号,早期皮层下白质不受累,胼胝体膝部和压部受累为重要征象;另外征象包括脑干皮质脊髓束和内、外囊受累及虎纹征。     

足月新生儿低血糖脑病的MRI表现

目的 探讨足月新生儿低血糖脑病的MRI表现.方法 回顾性分析16例低血糖脑病的MR资料,其中男10例,女6例,所有病例均在患者出生后6 d内进行,包括常规T1WI,T2WI和Flair,DWI扫描.其中4例1~3月后再次复查MR.结果 16例首次检查T1异常8例,表现为皮层下白质呈低信号,4例皮层呈高信号.T2异常6例,表现为高信号区.DWI异常12例,表现为对称性高信号区.分布部位:双侧顶枕叶10例,胼胝体压部4例,双额叶1例,双屏状核1例,侧脑室旁白质4例,小脑上脚、脑干腹侧1例.1~3月后复查4例,有2例表现为局限性脑皮层萎缩,胼胝体变细.结论 足月新生儿低血糖脑损伤最易发生顶枕叶后部脑组织,其次胼胝体,小脑亦可受累.DWI上对称性高信号具有一定的特征性.     

伴皮质下梗死和白质脑病常染色体显性遗传性脑动脉病CT平扫特点

目的：探讨伴皮质下梗死和白质脑病的常染色体显性遗传性脑动脉病（CADASIL）CT平扫特点。方法：对8例经临床、MRI、病理学及基因检查确诊为CADASIL患者的CT平扫资料进行回顾性分析。结果：CADASIL患者脑CT平扫特点主要表现为颞极、额叶前部白质疏松,可伴有腔隙性梗死灶,随年龄增长上述病灶逐渐加重。结论：CADASIL病例CT平扫存在特征性的脑白质病变,CT对该病的筛选有重要作用。     

MRI诊断Canavan病一例

患儿 男,4岁.出生后4个月开始出现头大,发育落后;近2年逐渐出现眼震,双下肢行走困难.尿枪:N-乙酰天冬氨酸(NAA)浓度增高.常规MRI表现:大脑皮层下白质弥漫对称性长T1、长T2信号,双侧苍白球、丘脑、中脑背盖、小脑齿状核、内外囊均受累,而脑室旁白质和壳核正常(图1,2).扩散加权成像(DWI)上受累的皮层下白质呈明显的高信号,受累灰质核团成等或高信号(图3).单体素点解析氢质子MR波谱(1H-MRS)上NAA峰显著升高(图4).MR诊断为Canavan病.     

吸毒引起中毒性脑病的MRI表现

目的探讨吸食毒品引起中毒性脑病的MRI表现.材料与方法4例男性,年龄28～40岁.均吸毒品海洛因.吸毒史2～4年.结果(1)临床表现4例均出现程度不同的锥体外系症状、精神症状和智力障碍.(2)MRI表现①脑白质受累型表现为半卵圆中心、内囊、胼胝体和小脑齿状核周围白质和中脑导水管周围白质对称性长T1和长T2改变,②神经核团受累型两侧小脑半球齿状核和两侧丘脑外侧核对称性长T1和长T2改变.结论长期大量吸食毒品对中枢神经系统产生明显的毒性作用.大脑、小脑半球白质和胼胝体、丘脑外侧核和小脑齿状核是主要的累及部位.     

亚急性1,2-二氯乙烷中毒性脑病的CT、MR表现

目的:探讨1,2-二氯乙烷中毒性脑病的CT、MR表现.方法:回顾性分析5例经临床证实的1,2-二氯乙烷中毒性脑病的CT和MR资料,CT检查5例,MR检查3例.结果:CT检查病灶表现为低密度,两侧对称.5例均广泛累及两侧大脑半球白质(累及皮层下弓形纤维为主).累及两侧齿状核4例,丘脑、苍白球受累各3例.3例MRI均表现为上述部位广泛性T1WI低信号,T2WI高信号.CT、MRI都显示脑回肿胀,脑室系统受压变小.结论:1,2-二氯乙烷中毒性脑病具有较典型的CT、MRI特征,结合毒物接触史可明确诊断.     

磁共振成像对孕产妇可逆性后部脑病综合征预后的诊断价值

目的 评价磁共振成像(MRI)对孕产妇可逆性后部脑病综合征(reversible posterior leukoencephalopathy syndrome,RPLS)预后的诊断价值.方法 收集临床确定为RPLS孕产妇7 例的MR资料.总结临床预后与患者早期病灶在T1WI、T2WI、DWI上的特征、分布、演变的关系.结果 7 例患者中仅1 例预后较差,问话不答、意识不清仍存在,其早期MRI示双侧额、顶、颞、枕叶皮层及白质、小脑、脑干、基底节大片状稍长T1稍长T2信号影,DWI仅示右侧基底节斑片状高信号,余大部分病灶未见显示,MRA、MRV均未见脑血管异常,复查MRI示病变仍存在.其余6 例预后较佳,视物不清、头痛、抽搐症状明显好转,其中5 例早期MRI示双侧顶叶、枕叶斑点片状稍长T1稍长T2信号影,DWI均未见病灶显示.5 例MRA、MRV均未见脑血管异常.1 例早期MRI仅示胼胝体压部斑片状稍长T1稍长T2信号影,DWI呈高信号,MRA示双侧大脑前动脉共干,MRV未见异常.结论 RPLS多累及顶、枕叶,一般预后较佳.大部分病灶DWI上呈低信号,提示RPLS是血管源性水肿.     

一氧化碳中毒迟发性脑病的MRI表现

目的:研究一氧化碳(CO)中毒迟发性脑病的MRI特征.方法:回顾性分析32例CO中毒迟发性脑病患者的MRI和临床资料.结果:CO中毒迟发性脑病MRI表现可分为三型:①神经核团受累型;②脑白质受累型;③皮层受累型.MRI特征:苍白球为对称性的卵圆形长T1、长T2信号,皮层下白质为对称性的弥漫、模糊云雾状长T1、长T2信号,侧脑室周围、半卵圆中心白质亦为对称云絮状长T1、长T2信号,胼胝体常受累.MRI显示苍白球合并脑白质受累者及皮层受累者,临床表现较重.结论:CO中毒迟发性脑病MRI表现有一定特征性,且能反应其病理过程,并对CO中毒迟发性脑病的诊断和评价临床表现、预后均有意义.     

Distribution of cranial MRI abnormalities in patients with symptomatic and subclinical CADASIL

Cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy (CADASIL) is a rare, inherited cause of early stroke and dementia, with a poor prognosis. This study was performed to clarify lesion appearance and pattern of lesion distribution in CADASIL. 20 members of a single family were tested for the CADASIL gene mutation and studied with cranial MRI. Scans were evaluated for lesion load and pattern of lesion distribution. 19 patients had cranial MRI, of whom 11 had normal MRI scans, were clinically unaffected and tested negative for the CADASIL gene mutation. The remaining eight patients had abnormal cranial MRI scans: seven patients were positive for the CADASIL gene mutation and one (untested) patient was severely clinically affected. Three of the patients who tested positive for the CADASIL gene mutation were clinically unaffected at the time of imaging. All eight patients with abnormal cranial MRI had subcortical white matter abnormalities, mostly in frontal and temporal lobes. Lesions involving the corpus callosum were present on sagittal T2 weighted images in four of five clinically affected and one of three clinically unaffected patients. Lesions involving the deep grey nuclei and the brain stem were common. On T1 weighted images, lesions were either poorly defined (confluent white matter hypointensity) or well defined (cystic infarcts or enlarged perivascular spaces). Atrophy was infrequent. Familiarity with the range of cranial MRI appearances may aid diagnosis of CADASIL. Recognition of cranial imaging features in asymptomatic CADASIL patients could prompt earlier diagnosis.     

2个CADASIL患者的弥散张量成像与20例正常人的比较

目的　分析2例CADASIL患者的MR特点及弥散张量指标的变化。方法　收集2例通过病理和基因检查确诊为CA DASIL的先证者的临床资料,对其进行常规MR扫描和弥散张量成像,将弥散张量成像的指标与20例正常志愿者的指标进行比较。结果　2例CADASIL患者的MR主要表现为双侧额顶叶白质内多发腔梗、脱髓鞘改变和双侧颞叶前部白质脱髓鞘。1例患者双侧外囊、内囊后肢、胼胝体膝部和压部的部分各向异性(FA)值均小于正常组的平均值减去2倍标准差,另1例患者左侧外囊的FA值小于对照组的平均值减去2倍标准差。结论　常规MR表现和弥散张量成像指标的测量均反映了CADASIL患者中存在严重的白质病变。     

MRI findings in neuro-beh?et's disease.

AIM: To evaluate the pattern and site of involvement in neuro-Beh?et's disease (NBD). MATERIALS AND METHODS: Twenty-one patients with NBD were evaluated. Using 1.5T magnetic resonance imaging (MRI), T1-weighted axial and sagittal images, gadolinium enhanced axial and coronal images and T2-weighted axial images were obtained. RESULTS: The brainstem, basal ganglia, cerebral white matter, internal capsule, thalamus and spinal cord were involved in eighteen, nine, nine, seven, six and two patients, respectively. In nine patients with cerebral white matter involvement, four had subcortical involvement and three had periventricular involvement, in addition to two patients with focal deep white matter lesions. Among the brainstem lesions, pons involvement was seen in fourteen patients, all had ventrally located lesions, and nine had tegmental involvement. Midbrain involvement was seen in fourteen patients; the cerebral peduncle was involved in 11 of these. Five patients had brainstem atrophy: two cases were demonstrated at initial MRI, the other three cases were seen on follow-up MRI. Pyramidal signs, the most common neurological signs, were demonstrated in fourteen patients. Follow-up MRI was obtained 10 days to 20 months after the initial MRI in eight cases; all showed changes in size, shape and site of involvement. After gadolinium enhancement, thirteen patients demonstrated mottled non-confluent enhancement in the brainstem (eight patients), posterior limb of the internal capsule (three patients), pachymeninges (two patients) and spinal cord (two patients). CONCLUSION: NBD manifests a reversible course, but chronic NBD may result in brainstem atrophy. Characteristic involvement along the corticospinal tract is well correlated with neurological signs.     

The spatial distribution of MR imaging abnormalities in cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy and their relationship to age and clinical features

BACKGROUND AND PURPOSE: Cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy (CADASIL) is a condition causing recurrent subcortical strokes. MR imaging, which shows focal lacunar infarcts and leukoaraiosis, plays a central role in the diagnosis and evaluation. We studied MR imaging abnormalities in a large prospectively recruited cohort of CADASIL patients to describe the spatial distribution of abnormalities, determine how this distribution alters with age, and identify any correlations with the clinical features of the disease. METHODS: In this study, 112 CADASIL subjects from 64 families were prospectively recruited. MR imaging scans were graded by a single neuroradiologist, by using the modified Scheltens scale, to quantify the severity of high-signal-intensity changes in different brain regions. RESULTS: Lesion load increased progressively with age. Scores were maximal in the frontal, parietal, and anterior temporal cortex, and the external capsule; intermediate in the pons; and relatively low in the corpus callosum, caudate, globus pallidus, cerebellum, midbrain, and medulla. Anterior temporal pole involvement was common at all ages and, when present, usually confluent, but this was absent in 33% of patients 20-29 years of age. A history of stroke correlated with total Scheltens score and internal capsule and pontine scores. Dementia correlated with total Scheltens score and subcortical white matter score, whereas depression correlated with subcortical white matter score but not total Scheltens score. CONCLUSIONS: There is a characteristic pattern of MR imaging abnormalities in CADASIL that aids in differential diagnosis; however, some characteristic features, such as anterior temporal pole involvement, can be absent. MR imaging lesion load correlated with some clinical features including stroke and dementia, whereas depression is more common in individuals with deep white matter changes.     

长巨脑动脉的影像诊断

目的探讨长巨脑动脉的影像特征.材料与方法对13例患者的MRI表现、DSA或MRA显示的异常血管分布和形态进行分析.结果MRI能够显示位于桥前池、鞍上池等处粗大的血管流空信号、病变压迫的确切部位(颅神经、脑干、颞叶内侧)、脑缺血灶以及伴随的脑动静脉畸形.无以往的出血表现.血管造影显示延长、增宽和扭曲的脑血管,8例发生在椎-基底动脉,2例发生在颈动脉,3例两系统同时受累.有1例伴有一侧颈动脉闭塞,另2例分别伴发脑动静脉畸形和多发脑动脉瘤.结论MRI和血管造影技术相结合,有助于对该病进行全面评价.     

常染色体显性遗传性脑动脉病伴皮层下梗死和白质脑病患者的MR定量指标及其与临床的关系

目的 对常染色体显性遗传性脑动脉病伴皮层下梗死和白质脑病(CADASIL)患者的白质高信号和脑体积进行定量分析,并探讨其与临床的关系.方法 15例通过病理检查确诊为CADASIL的患者进行常规MR扫描,统计脑半卵圆中心、内囊后肢、外囊、胼胝体和颞极白质受病变累及情况.利用计算机后处理软件计算标准化颅脑体积和白质高信号占颅脑体积的百分比,并与年龄、美国国立卫生研究院卒中量表(NIHSS)和简易精神状态检查(MMSE)量表评分进行Spearman相关性分析.结果 CADASIL患者的白质病变累及部位依次为:半卵圆中心(13/15)、颞极白质(10/15)、外囊(8/15)、内囊后肢(5/15)、胼胝体(4/15).白质高信号占颅脑体积的百分比为(5.7±1.4)%,标准化颅脑体积为(1602±58)×103mm3.年龄与标准化颅脑体积呈负相关(r=-0.555,P＜0.05);白质高信号百分比与NIHSS、MMSE量表评分分别呈正、负相关(r=0.522,P＜0.05;r=-0.679,P＜0.01);标准化颅脑体积与NIHSS评分呈负相关(r=-0.624,P＜0.05).结论 CADASIL患者的白质高信号和脑体积可以定量测量,这两种影像学指标可以在一定程度上反映患者的病情.白质高信号的发展可能预示患者认知功能的下降.     

Subcortical lacunar lesions: an MR imaging finding in patients with cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy

PURPOSE: To assess the prevalence and distribution of subcortical lacunar lesions (SLLs) in patients with cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy (CADASIL), to determine whether SLLs are an abnormal finding by studying their prevalence in healthy subjects, and to assess whether SLLs occur in other conditions associated with small vessel disease and white matter areas of high signal intensity (WMH). MATERIALS AND METHODS: The presence of SLLs, their location, and their relation to other abnormalities were assessed on magnetic resonance (MR) images (T1-weighted, T2-weighted, and fluid-attenuated inversion-recovery) obtained in 34 CADASIL patients and 20 healthy family members. Three additional control groups of healthy volunteers, elderly patients with vascular risk factors, and patients with another hereditary small vessel disease were also screened for the presence and location of SLLs. Sensitivity and specificity of the presence of SLLs for the diagnosis of CADASIL were assessed. RESULTS: SLLs were found in 20 (59%) of CADASIL patients. Incidence of SLLs increased with age (20%, <30 years; 50%, 30-50 years; 80%, >50 years). SLLs invariably occurred in the anterior temporal lobes and in areas where diffuse WMH expanded into arcuate fibers. From the anterior temporal lobe, the lesions could extend dorsally into the temporal lobes and rostrally into the frontal lobes. Lesions were not found in the parietal and occipital lobes. None of the control subjects had SLLs. Specificity and sensitivity of SLLs for CADASIL were 100% and 59%, respectively. CONCLUSION: SLLs are an abnormal finding at MR imaging that frequently occur in CADASIL patients.     

Cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy: structural MR imaging changes and apolipoprotein E genotype

BACKGROUND AND PURPOSE: Apolipoprotein E (apoE) genotype plays an important role in the development, maintenance, and response to injury of the central nervous system. It has been suggested that apoE epsilon4 genotype is a risk factor for several neurologic disorders. We investigated the correlation between the apoE genotype and radiologic data in patients with cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy (CADASIL). METHODS: T1-weighted, dual fast spin-echo, T2*-weighted gradient echo, and fluid-attenuated inversion recovery MR imaging scans were obtained from 36 CADASIL patients (21-59 years of age). The number of lacunar infarcts and microbleeds and the presence of subcortical lacunar lesions were determined. The amount of white matter hyperintensities was assessed by using semiautomated segmentation software. The relation between the radiologic endophenotype of CADASIL and the apoE genotype was assessed by using a Student t test for unpaired data and Fisher exact test. RESULTS: White matter hyperintensities, lacunar infarcts, microbleeds, and subcortical lacunar lesions were not found to be associated with the presence of an epsilon4 allele. CONCLUSION: The variability of structural MR imaging lesions in CADASIL is independent of apoE genotype and other processes must underlie the variable natural history of the disease.     

Cortical hypometabolism and crossed cerebellar diaschisis suggest subcortically induced disconnection in CADASIL: an 18F-FDG PET study.

Cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy (CADASIL) is an inherited small-vessel disease caused by mutations in the NOTCH3 gene. As in sporadic small-vessel disease, ischemic lesions are largely confined to subcortical structures, whereas the cortex is spared. CADASIL, therefore, may serve as a model to study subcortically induced remote effects. The purpose of this study was to evaluate with (18)F-FDG PET whether regional cerebral metabolic rate of glucose (rCMRglc) is altered in CADASIL patients and, if so, whether there is evidence of subcortically induced disconnection. METHODS: Eleven CADASIL patients (7 women, 4 men; mean age, 55.8 +/- 6.7 y) without cortical lesions on brain MR images underwent PET after intravenous injection of 120 MBq (18)F-FDG, with calculation of rCMRglc according to a previously published method. For further processing, patient studies were registered to a template of a healthy control group and region-of-interest-based and voxelwise comparisons were performed. RESULTS: In CADASIL patients, mean rCMRglc was significantly reduced in all cortical and subcortical structures, compared with the values in healthy volunteers. In the subcortical gray matter, metabolic rates, given as the percentage of the mean of healthy volunteers, were 49.7%, 65.3%, and 51.6% in the caudate, putamen, and thalamus, respectively. Among cortical structures, the values were 66.9%, 67.9%, 67.2%, and 76.5% for the frontal, parietal, temporal, and occipital lobes, respectively. On an individual level, most patients showed marked asymmetry and inhomogeneities of cortical glucose metabolism. In 6 (55%) CADASIL patients, there was evidence of crossed cerebellar diaschisis. CONCLUSION: This study showed that cortical glucose metabolism is significantly lower in CADASIL patients than in healthy volunteers. The observed decrease in rCMRglc may in part be explained by a reduction of cerebral blood flow and neuronal loss. In addition, our data provide evidence of remote effects secondary to the functional disruption of subcortical fiber tracts in this particular type of small-vessel disease.     

妊娠期高血压疾病合并可逆性后部脑病综合征的影像学特征

目的：探讨妊娠期高血压疾病合并可逆性后部脑病综合征（RPES）的影像学特征,提高对此病的认识。方法：回顾性分析35例妊娠期高血压合并RPES患者的临床及影像学特征。首次影像学检查：CT检查19例,MRI检查16例。影像学复查：17例患者于首次检查后3～14d进行复查,平均复查间隔时间为6d,其中CT复查7例,MRI复查10例。结果：RPES主要表现为对称性皮层下脑水肿,于CT图像上呈不规则形低密度区,于MRT。wI上呈高信号,主要位于双侧顶枕叶（32／35）,其次是额叶（23／35）和颞叶（16／35）,也累及深部脑白质（15／35）和基底节区（11／35）,小脑（5／35）和脑干（3／35）偶有累及;合并蛛网膜下腔出血2例。MRI增强扫描：5例患者病灶均未见强化;MRA：左侧大脑中动脉闭塞1例,正常3例;2例患者MRV检查均正常;DWI：病灶多呈等信号或低信号（10／12）,ADC图上呈高信号;DWI示2例病灶中出现斑点状高信号,ADC图提示此区域扩散受限。复查：17例患者治疗后CT或MRI复查显示病灶完全消失13例,病灶范围明显缩小4例。结论：妊娠期高血压疾病合并RPES的影像学表现有一定特征性,主要表现为皮层下脑白质血管源性水肿,以累及后循环供血区域为主,双侧较对称,治疗后病变范围迅速减小甚至消失。