系统性红斑狼疮性脑病的MRI表现

目的 探讨系统性红斑狼疮性脑病(NPSLE)的MRI特点.方法 回顾性分析21例经临床证实的NPSLE患者颅脑MRI图像,根据其DWI行ADC图重建,测量病灶及正常脑组织的ADC值并进行对照.结果 21例NPSLE患者中颅脑MRI检查发现异常者20例,阳性率为95%.MRI异常表现包括:(1)DWI高信号14例,11例多发,3例单发;14例中4例合并脑萎缩;病灶部位皮层下白质较皮层多见;皮层DWI高信号病灶ADC值减低(t=2.513,P=0.019),白质DWI高信号病灶ADC值升高(t=2.877,P=0.007).(2)单纯脑萎缩2例.(3)脑白质稀疏2例.(4)软化灶2例,其中1例合并脑萎缩.(5)5例NPSLE行MRI增强检查,2例强化,表现为沿脑回分布的条状、小片状强化.结论 MRI在判断NPSLE脑部病变的有无、部位、进展及转归中起重要作用.     

脑脂肪栓塞的CT和MRI诊断(附3例分析)

目的 :分析脑脂肪栓塞 (CFE)的CT和MRI表现 ,以提高对此病的早期诊断。方法 :对 3例CFE患者的临床及CT和MRI资料进行分析。结果 :3例CFE患者CT检查均为阴性 ,MRI示双侧额叶皮层下脑白质区、基底节、放射冠、半卵圆中心区多发散在点状异常信号影 ,1例T1WI表现为低信号 ,2例未见异常 ,3例T2 WI均表现为点状较高信号 ,DWI上 3例均有点状高信号。结论 :有近期骨折病史者 ,一旦出现神经系统症状 ,要想到CFE的可能 ,应早期行颅脑MRI检查 ,常规选择T1WI、T2 WI和DWI多种序列成像技术进行检查。     

粘多糖贮积症的颅脑CT及MRI表现

目的:探讨粘多糖贮积症的颅脑CT及MRI表现特征.方法:对经临床和实验室检查确诊为粘多糖贮积症的6例患者行颅脑CT及MRI扫描,分析其影像学表现.6例患者均行CT平扫,其中2例行CT增强扫描;6例患者中4例行MRI检查,其中1例行增强扫描.结果:CT平扫6例中4例显示两侧大脑半球白质内散在低密度灶,增强后病灶未见强化;1例仅见脑室扩大,1例未见异常.MRI检查4例中2例显示脑实质多发小囊状信号由脑室边缘向各脑叶呈放射状分布,脑白质病变呈斑片状长T1、长T2信号,增强后所有脑内病灶均未见强化;1例脑室扩大,白质减少;1例仅显示脑白质信号异常.MRI还显示3例齿状突发育不良伴周围软组织增厚,2例颅颈结合区硬脑脊膜增厚伴椎管狭窄.本组1例行脑组织活检,电镜显示神经元内有空泡状包涵体及斑马体.结论:粘多糖贮积症的颅脑CT及MRI表现有一定特征,可在一定程度上为临床诊断、估计病损程度、监察病变进程及选择治疗方案提供依据.     

后循环可恢复性脑病综合症（PRES）的MR诊断

目的：明确PRES的发病机制、临床及影像学表现，明确MRI在该病诊断中的作用。材料与方法：对8例可疑病人进行临床及影像学检查，跟踪随访并进行回顾性分析。结果：8例患者均出现双侧长T1、长T2信号，其中6例（75％）患者DWI检查呈显著低信号，ADC值明显高于正常脑白质。而有2例（25％）患者DWI呈稍高信号。经临床治疗，4例患者完全康复，另外4例患者复查MR仍可见片状长T1长T2信号。结论：PRES的MRI检查有一定特异性，因此在该病诊断中具有重要的诊断价值。     

儿童急性坏死性脑病的影像学分析

目的分析儿童急性坏死性脑病(ANEC)的颅脑影像学特征,探讨其对临床的指导价值。方法回顾性分析2013年1月至2018年10月武汉儿童医院22例确诊为ANEC患儿的临床及影像资料。患儿病初均有高热,前驱感染后迅速出现神经功能恶化。首次影像检查中,所有患儿均行头颅MRI检查,其中6例MRI检查前行头颅CT检查。MRI随访中,4例失访,6例仅行1次短期随访(<14 d),12例接受1~2次短期及1~4次长期随访(>14 d)。影像学检查重点观察丘脑、脑干、脑白质和基底节区等部位,以及整个随访中是否有出血及软化灶形成。结果所有ANEC患儿的影像学表现中均累及双侧丘脑,其他对称病变部位包括大脑白质(14例)、基底节区(15例)、脑干(16例)、小脑(9例)、胼胝体(2例)和海马(1例),不对称病灶患儿3例,分别见于大脑白质(2例)及小脑(1例)。最典型的头颅MRI表现为急性期在表观扩散系数(ADC)图上,丘脑呈"三色模式"(中央高信号和周围低信号环,以及丘脑周围高信号)或"双色模式"(丘脑中央低信号及边缘高信号)。影像学随访中,MRI上出现出血、脑软化可能提示临床预后差。结论ANEC为快速进展型脑病,具有典型影像学特点,出血、脑软化可能提示不良预后。     

成人型神经元核内包涵体病的影像学表现

目的:探讨成人型神经元核内包涵体病(NIID)的影像学特征。方法:收集5例NIID的临床与影像学资料,分析其CT和MRI表现。结果:4例行CT平扫示脑白质呈低密度。4例行MRI扫描,T_1WI示脑白质呈低信号,T_2WI、T_2FLAIR呈高信号,DWI示皮髓质交界处(U型纤维)持续性高信号,即皮层下火焰征、尿布征;2例行增强扫描,未见明显强化。结论:NIID的影像学表现具有一定特征,掌握其影像学表现可提高对该病的诊断水平。     

成人脑白质病的CT、MRI诊断

目的 探讨成人脑白质病的影像学特征，为临床诊断和治疗提供可靠依据。资料与方法对经临床证实的63例脑白质病影像学表现进行总结分析。结果 血管性脱髓鞘42例，硬化性脱髓鞘7例，感染性脱髓鞘6例，中毒性脱髓鞘4例，脑白质营养不良性脱髓鞘4例。CT表现为脑白质内多发斑片状低密度区，MRI表现为脑白质内多发长T2信号。结论MRI较CT能更清晰地显示脑白质异常，准确地反映病理改变的特点，有助于进一步提高对脑白质病变的诊断水平。     

继发性骨肉瘤的临床特点及影像学表现

目的:分析继发性骨肉瘤的临床特点及影像学表现.方法:回顾性分析经手术病理证实的25例继发性骨肉瘤患者的病例资料.25例均行X线及CT检查(5例行增强CT),16例行MRI增强检查.结果:本组患者的中位年龄45岁(14～76岁),中位恶变时间为8年(0.5～18.0年).25例中骨纤维结构不良、骨母细胞瘤等良性肿瘤或肿瘤样病变恶变12例,表现为溶骨性破坏、软组织肿块形成及病灶迅速增大等与原发骨肉瘤相仿的影像学改变;骨巨细胞瘤植骨后恶变继发性骨肉瘤8例、金属植入相关的继发性骨肉瘤2例,均表现为移植骨吸收、周围出现明显软组织肿块及肿瘤骨形成;放疗后继发性骨肉瘤2例,以成骨性骨质破坏为主;Paget病继发性骨肉瘤1例,表现为在患骨增粗、不规则变形基础上,出现溶骨性破坏及软组织肿块.病理结果:镜下有不同程度的细胞异形性、肿瘤骨形成.所有病例术后随访时间为1.5～12.0年(平均3.4年),8例出现肺部转移.结论:病理组织学上继发性骨肉瘤与原发性骨肉瘤无明显差异,但结合其临床资料及影像学表现可明确诊断.     

甲基丙二酸尿症及丙酸尿症的颅脑MRI研究

目的:探讨甲基丙二酸尿症及丙酸尿症的颅脑MRI表现。方法:对16例甲基丙二酸尿症和丙酸尿症的婴幼患儿的临床资料及颅脑MRI进行分析总结。结果:16例中男10例,女6例,发病年龄为出生后～2岁。治疗前行头颅MRI检查8例,表现为脑萎缩5例,其中3例伴脑白质减少,另2例伴双侧基底节信号异常,表现为T1FLAIR稍低、T2FLAIR高信号、DWI高信号;头颅CT检查1例,表现为交通性脑积水。通过治疗后随访MRI7例,表现为MRI和DWI阴性1例,双侧基底节持续T1FLAIR稍低、T2FLAIR高信号、DWI稍高信号1例,内囊前后肢及脑干T1FLAIR低信号1例;余4例中,MRI表现好转2例,呈进行性改变2例。结论:甲基丙二酸尿症和丙酸尿症的MRI表现缺乏特异性,主要为不同程度的脑萎缩、髓鞘化延迟和基底节的异常信号,特别是苍白球。MRI的异常改变可通过合理治疗而有所改善,然而长期的异常影像学改变则预示着神经系统呈不可逆的、进行性的损害。     

佩梅病的头颅MRI表现及其与临床、基因分型的关系

目的 探讨佩梅病( PMD)患儿的头颅MRI特点,以及与临床及基因分型的关系.方法 回顾性分析16例经临床诊断为佩梅病患儿的临床和影像资料.患儿均为男性,年龄5个月至9岁8个月.由儿科神经医师对患儿的症状和体征进行检查,将其按照临床症状进行临床分型.由影像科医师对头颅MRI图像的特点进行分析,病灶的位置包括苍白球、锥体束、胼胝体、小脑白质、半卵圆中心,判断大、小脑是否萎缩、是否有“豹纹征”.结果 临床诊断经典型佩梅病8例,中间型7例,先天型1例.16例佩梅病患儿MRI均以广泛的脑白质髓鞘化延迟为特点,病灶累及苍白球13例、锥体束7例、胼胝体11例、小脑白质7例、半卵圆中心12例、脑萎缩5例、小脑萎缩1例,5例有“豹纹征”.锥体束和小脑白质受累在点突变患儿中多见;临床症状较重的中间型及先天型患儿出现小脑白质病变频率较高;“豹纹征”多见于经典型患儿,提示患儿的髓鞘化程度相对较高.结论 佩梅病患儿的头颅MRI具有典型的影像特点,其影像学表现与临床分型和基因突变类型有一定的相关性.     

Disseminated necrotizing leukoencephalopathy following chemoradiation therapy for acute lymphoblastic leukemia

Disseminated necrotizing leukoencephalopathy (DNL) is a potentially fatal complication of treatment involving intrathecal administration of chemotherapeutic agents such as methotrexate (MTX) alone or in combination with cranial radiotherapy (RT). We describe a case of acute lymphoblastic leukemia (ALL) treated with high-dose intravenous and intrathecal methotrexate combined with craniospinal RT resulting in DNL. Typical MR imaging features of progressive deep white matter lesions showing a characteristic pattern of enhancement after contrast was seen in this case. Deep white matter lesions with ring-like enhancement and calcifications were seen on CT; it showed a mass effect at one stage, which is not typical for DNL. Long-term clinical and imaging follow-up were helpful for the diagnosis in this case. This work was presented at the 280th Japan Radiological Society meeting, Chihokai Kansai, July 2, 2005     

MRI in methotrexate-related leukoencephalopathy: Disseminated necrotising leukoencephalopathy in comparison with mild leukoencephalopathy

We report two fatal cases of methotrexate (MTX)-induced disseminated necrotising leukoencephalopathy (DNL) in which MRI was repeated from the onset. Initial T2-weighted images showed multiple areas of high signal, mainly in deep cerebral white matter, which on follow-up, spread and coalesced to involve the entire white matter. Small irregular low-signal foci on T2-weighted images were seen within the high-signal lesions. Multiple areas of contrast enhancement corresponded to these low-signal foci. The condition of both patients deteriorated and they died. We compared their MRI findings with those of seven patients with mild MTX-related leukoencephalopathy, six of whom were asymptomatic; one had transient neurological symptoms. They showed no contrast enhancement, but rather mild-to-moderate diffuse high signal in deep white matter, which later disappeared. These findings suggest that multiple low-signal foci on T2-weighted images with contrast enhancement may be characteristic of DNL, and that contrast-enhanced imaging is useful to differentiate this condition from mild leukoencephalopathy.     

Leukoencephalopathy following high-dose intravenous methotrexate chemotherapy: Quantitative assessment of white matter attenuation using computed tomography

Summary A clinical or subclinical leukoencephalopathy occurs in some children after treatment of acute lymphatic leukemia with prophylactic cranial radiation therapy and parenteral or intrathecal methotrexate. We have observed a similar clinical leukoencephalopathy in patients with bone tumors treated with intravenous high-dose methotrexate and citrovorum factor without cranial irradiation. CT scans of such patients may indicate decreased white matter attenuation, but visual appraisal of this phenomenon is occasionally misleading. A computerized method for analyzing white matter hypodensity by determining the mean attenuation coefficient for one or several contiguous CT slices has therefore been developed. Serial comparisons of this mean attenuation coefficient appear to be more reliable than simple visual appraisal.     

Osteogenic sarcoma: MR signal abnormalities of the brain in asymptomatic patients treated with high-dose methotrexate

The advent of lesions with high signal intensity in periventricular white matter was incidentally observed on T2-weighted images in one patient who underwent magnetic resonance (MR) imaging of the brain after administration of high-dose methotrexate (HDMTX) for osteogenic sarcoma. Twenty-one additional symptom-free patients who had been treated with the same regimen and 10 patients who had undergone cisplatin-based chemotherapy for testicular cancer also underwent examination. Fourteen of the patients with osteosarcoma showed high-signal-intensity lesions in white matter on T2-weighted images. The interval between the last course of chemotherapy and MR imaging was a factor in this finding, as 12 of 14 patients who underwent examination within 2 years after chemotherapy had a positive finding, as opposed to two of eight patients who underwent examination later. The patients with testicular cancer had normal MR images. The occurrence of MR imaging abnormalities in asymptomatic patients treated with HDMTX for osteogenic sarcoma may be subclinical evidence of treatment-related central nervous system toxicity.     

可逆性胼胝体压部病变综合征的磁共振成像诊断及预后评估

目的探讨可逆性胼胝体压部病变综合征的磁共振成像(MRI),分析其预后。方法回顾性分析2014年1月至2017年12月经我院诊断的50例可逆性胼胝体压部病变综合征的MRI影像学资料,分析患者的影像学特征。结果MRI诊断表现胼胝体压部孤立性,圆形或弧形,少数为斑片状,边界清晰。4例T1WI信号改变不明显,其余患者T1WI呈等或稍低信号,T2WI呈稍高信号,FLAIR为稍高信号,信号均匀,病变周围水肿和占位效应不明显,44例T1WI增强扫描病灶无明显强化特征;DWI呈明显高信号且表现扩散系数(ADC)呈低信号;5例行磁敏感加权成像(SWI)检查,4例行MRS检查,5例行MRA检查,结果未见异常特征;3例行扩散张量成像(DTI)检查显示各向异性分数(FA)值减低。45例复查MRI表现为胼胝体压部病变完全消失,无神经系统受累症状,预后效果好;3例DWI信号欠均匀,中央区见稍低信号,预后较差;1例随访发现患有严重神经系统后遗症,四肢无自主运动,长期卧床,预后不良。结论MRI能为RESLES临床诊断提供重要依据,结合其临床症状,为临床诊治提供重要参考依据,一般预后良好。     

脊柱滑膜肉瘤的影像特征分析

目的 探讨脊柱滑膜肉瘤的影像表现,提高对该病的认识.方法 回顾性分析经手术病理证实的4例(男2例,女2例)脊柱滑膜肉瘤的临床及影像资料,重点分析影像特点及手术病理特征.结果 4例患者均行CT及MRI平扫,3例患者行CT及MRI增强检查.CT平扫等密度2例,稍高密度2例;增强扫描不均匀强化3例.T1WI序列:2例低信号,2例等信号;T2WI序列:1例高信号,1例稍高信号,2例混杂高信号;T2WI压脂序列:2例高信号,1例混杂高信号,1例稍高信号;DWI序列:4例明显高信号.T1WI增强序列:1例明显强化,2例不均匀强化.结论 脊柱滑膜肉瘤CT及MRI影像表现具有一定的特征性,结合临床表现有助于提高对本病的认识及诊断.     

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.     

磁共振弥散加权成像在脑梗死诊断与评估中的应用研究

目的:研究磁共振弥散加权成像在脑梗死诊断与评估方面的作用。方法:本组共18例,均接受包括弥散加权成像(DWI)在内的颅脑磁共振检查。结果:脑梗死随着病变时间的增加,其表观弥散系数(ADC)发生一系列的变化,在急性期病变局部的ADC减低,在DWI中显示为高信号,在ADC图像上显示为低信号,稳定期病变局部的ADC逐渐恢复到正常水平附近,慢性期病变局部的ADC增加,在DWI呈低信号,在ADC图像上呈高信号。结论:磁共振弥散加权成像能比较准确、可靠地诊断早期脑梗死并反映脑梗死的病理生理基础。     

成人幕上毛细胞型星形细胞瘤的MRI诊断

目的：探讨成人幕上毛细胞型星形细胞瘤的MRI影像表现。方法：回顾性分析16例病理证实的成人幕上毛细胞型星形细胞瘤的MRI影像资料。结果：16例中单发14例，多发2例。7例肿块位于脑表面者，相邻的颅骨均见弧形受压、变薄。肿块呈囊实性，椭圆形，境界清楚，无瘤周水肿，T1WI呈低信号，T2WI呈混杂高信号，增强后实性部分呈多环状或不规则强化，囊壁强化或无强化。结论：成人幕上大脑半球毛细胞型星形细胞瘤的MRI表现具有一定特征，MRI可提示诊断和指导临床治疗。     

AIDS脑部病变影像学表现分析

目的总结AIDS脑部病变影像学表现,为AIDS脑部病变的影像诊断提供依据。方法回顾性分析19例神经系统型AIDS患者脑部CT和MRI表现。结果5例HIV脑炎中,3例表现为双侧大脑半球白质区对称性异常信号,2例表现为脑萎缩。2例弓形体脑炎影像学表现为基底节区和额顶叶多发密度或/和信号异常,增强T1WI呈多发环状高信号。3例脑淋巴瘤分别表现为双侧大脑半球单发或多发结节,周围伴水肿,增强T1WI呈结节状或不均匀强化。3例脑梗塞表现为基底节区局限性低密度影。2例进行性多灶性白质脑病表现为额顶叶脑白质区多发斑片状异常信号。1例霉菌感染表现为脑干信号异常,增强T1WI呈环状强化;1例霉菌性脑膜炎和2例单纯颅内压增高患者,影像学无异常表现。结论CT和MRI检查可以发现大部分AIDS脑部病变,并可根据影像学表现和其它相关检查做出定性诊断。