妊娠相关性脑静脉及静脉窦血栓形成和可逆性后部白质脑病的磁共振鉴别

目的探讨MRI和MRV在妊娠相关性脑静脉及静脉窦血栓形成(CVST)和可逆性后部白质脑病综合征(RPLS)鉴别诊断中的价值。方法回顾性分析3例妊娠相关性CVST和6例重度子痫前期、子痫发生RPLS患者的影像学资料。所有患者均行MRI和DSA检查,其中7例患者行MRV检查。结果 3例CVST患者中,1例孤立性大脑上静脉前组血栓形成,MRI表现为相应部位T1WI低、等信号,T2WI、FLAIR等、稍高信号,DWI为等、高信号,ADC图为低、稍高信号;2例横窦血栓形成,表现为双侧枕叶皮质、皮质下白质片状T1WI低信号,T2WI、FLAIR高信号,DWI、ADC高信号,可不对称性地累及顶叶、小脑半球,MRV与DSA检查结果相符。6例RPLS患者MRI显示双侧顶、枕叶皮质、皮质下白质多发性、斑片状、对称性病变,部分严重患者大脑半球呈弥漫性、大片状受累,表现为T1WI低信号,T2WI、FLAIR高信号,DWI、ADC高信号;1例患者MRV检查示左侧横窦未显影,DSA检查示左侧横窦通畅。结论横窦血栓形成和RPLS患者MRI均显示血管源性脑水肿,两者脑水肿主要发生于双侧枕、顶叶,但前者范围较局限,后者范围更广泛,可累及基底节、额叶、颞叶。RPLS患者MRV检查可有假阳性,DSA是鉴别两者的重要检查方法。     

可逆性后部白质脑病综合征的临床及影像学特点

目的 探讨可逆性后部白质脑病综合征（PRES）的临床和影像学特点。方法 回顾性分析7例PRES患者临床及影像学资料。结果 本组继发于妊娠高血压综合征3例，肾功能衰竭3例，高血压1例。临床表现：7例均有头痛及视物模糊，伴有癫痫发作6例，恶心、呕吐4例，轻偏瘫、共济失调各1例。6例行头颅CT检查，3例枕叶低密度影，其中2例广泛脑白质水肿；1例多发小血肿；2例未发现异常。7例MRI检查显示枕叶均受累，同时伴小脑受累3例，脑干2例，额顶叶皮质下白质2例，尾状核、丘脑各1例。在脑叶呈脑回样、在其他部位呈斑片样异常信号；T1WI呈略低或等信号，T2WI和Fair像呈高信号。2例增强扫描1例无强化，1例呈脑回样、斑片样和环状强化。4例DWI扫描，2例呈略高信号，1例呈低信号，1例未见异常。结论 头痛、视觉障碍和癫痫发作是PRES主要临床表现，影像学特征主要为大脑后部白质对称性长T1、长T2信号。     

Marchiafava-Bignami病的临床及影像学研究

目的 探讨Marchiafava-Bignami病(MBD)的临床及影像学改变.方法 回顾性分析了7例MBD患者的临床和CT、MRI资料,包括病灶形态、分布、信号或密度改变等影像学特征:4例同时行CT和MRI检查,2例仅行CT检查,1例仅行MRJ检查.结果 本组患者急性型5例,均表现为胼胝体肿胀及长T1、长T2信号改变,均有双侧脑室周围白质、额叶皮层下白质对称性累及:慢性型2例,胼胝体明显萎缩变薄,并呈长T1、长T2信号及FLAIR像点片状或线样低信号灶.5例患者DWI显示病灶区信号明显增高并有2例出现弥散受限改变.结论 MBD具有特征性MRJ表现,其影像学改变可能反映其临床及预后.     

可逆性脑后部白质病变综合征影像学特点分析

目的探讨可逆性脑后部白质病变综合征的影像学特点。方法回顾性分析11例可逆性脑后部白质病变综合征患者的影像学资料。结果患者中累及枕叶9例,顶叶8例,额叶8例,基底节6例,颞叶2例,胼胝体1例和小脑1例。CT平扫示枕叶、顶叶、额叶、基底节、颞叶、胼胝体和小脑等低密度。MRI平扫示T_1WI为低信号、T_2WI及Flair为高信号。DWI可呈等或稍高信号,ADC可呈等、稍高、高或低信号。结论可逆性脑后部白质病变综合征可累及部位主要局限于顶枕叶,但额叶、基底节、颞叶、胼胝体及小脑等部位亦可受累。Flair、DWI和ADC序列对病变最为敏感。     

表现为家族性偏头痛的CADASIL家系的影像学特点

目的探讨伴皮层下梗死和白质脑病的常染色体显性遗传性脑病(CADASIL)家系的核磁共振(MRI)特点,提高对本病脑内MRI表现的认识。方法记录该CADASIL家系先证者及其亲属的临床表现及影像学检查,并行NOTCH3基因检测。结果本组6例中5例检出NOTCH3基因第14外显子C2182T突变,其中3例与MRI初诊结果一致。头颅核磁共振显示双侧额叶皮层下与侧脑室旁白质内广泛融合的病灶,基本对称性分布的稍长T1T2信号,T2FLAIR呈高信号者4例;外囊T2WI呈高信号3例;基底节区、丘脑腔隙性梗死4例;脑干T2WI呈高信号2例;脑内微出血3例;未见双侧颞极白质病灶(O’Sullivin征)。结论 CADASIL病例MRI存在特征性的病变,MRI对该病的诊断有重要作用。     

脑后部可逆性脑病综合征MRI及DWI表现及临床意义

目的分析脑后部可逆性脑病MRI及DWI的影像学特点。方法 15例经临床诊治及MRI检查的脑后可逆性脑病综合征(Poster revers Tble encephalopathy.syndrome,PRES)患者的资料,均常规MRI及DWI扫描并计算出ADC图。结果 15例双侧大脑半球后部皮层受损,以枕叶、顶叶、颞叶好发,其中11例伴额叶受损,3例伴侧脑室深部白质、基底节受损,2例伴丘脑、小脑半球受损。13例发病时以血管源性水肿为主,2例为细胞毒性水肿。5例在首次检查后7~21d复查,3例病灶为可逆性完全消失,2例大部分病灶可逆性消失,局部有残留病灶。结论脑后部可逆性脑病综合征影像学具有特点,DWI、ADC容易区分血管源性水肿和细胞毒性水肿病灶,有助于临床鉴别及判断预后。     

可逆性后部白质脑病综合征临床特点及影像学改变--附12例临床分析

目的：探讨可逆性后部白质脑病综合征（PRES ）的临床特点和影像学改变。方法回顾性分析12例PRES患者的临床和影像学资料。结果原发病为慢性酒精中毒1例，系统性红斑狼疮伴特发性血小板减少性紫癜1例，余10例均与妊娠相关，其中7例原发病为妊娠高血压综合征（妊高征）。临床主要表现为癫痫发作（9例）、视力障碍（5例）、意识障碍（9例）、头痛（7例）、恶心呕吐（3例）；10例患者存在肾功能损害。颅脑C T 及M R检查示病灶累及顶枕叶（10例）、额叶（3例）、基底节（3例）、小脑（2例）和脑干（2例），M RI均呈长T1长T2信号，T2 flair高信号，DWI等信号（7例）或略高信号（1例）；颅脑CT 呈低密度（8例）或等密度（2例）；边界欠清。经积极对因对症治疗，本组患者症状在中位数4d（QL3.25d，QU5d）后几乎完全缓解，影像学表现在中位数9 d（QL 7.25 d ，QU 10.75 d）后得到完全或大部分恢复。结论 PRES以癫痫发作、视力障碍、意识障碍、头痛、恶心呕吐为主要临床表现，影像学改变以可逆的、多分布于后循环供血区的皮层下脑白质血管源性水肿为特点， MRI呈T1低信号、T2及T2 flair高信号，DWI等/略高信号，CT呈低/等密度。积极治疗后多数患者症状可完全缓解，影像学表现可完全或大部分恢复。     

以可逆性皮层盲为主要表现的可逆性后部白质脑病综合征三例临床和影像学分析

目的探讨主要表现为皮层盲的可逆性后部白质脑病综合征的临床与影像学表现、早期诊断和治疗。方法回顾性分析主要表现为可逆性皮层盲的慢性肾功能衰竭患者1例、先兆子痫和子痫患者各1例的临床、腰椎穿刺和影像学资料。结果3例患者均出现急性双侧完全性皮层盲,伴有高血压、头痛,1例伴有癫痫发作。腰椎穿刺示轻度颅内压增高。头颅MRI示双侧枕叶皮层或皮层下对称性异常信号,T2WI、FLAIR为高信号,DWI为低或等信号,ADC为高信号,提示血管源性水肿。3例患者均诊断为可逆性后部白质脑病综合征,经控制血压、脱水降颅压等治疗,皮层盲在2天内均完全好转,2周后复查头MRI病灶完全消失。结论可逆性皮层盲是可逆性后部白质脑病综合征最为特征性的症状之一,是由于双侧枕叶皮层或皮层下血管源性水肿所致。     

子癇患者的脑部磁共振改变

目的：探讨子癇患者的脑部MRI改变。方法：回顾性分析16例子患者的脑部MRI资料,总结其特点。结果：16例患者均表现为大脑半球皮质、皮质下白质多发病灶,T1WI低信号、T2WI、Flair高信号,DWI等或高信号、表观弥散系数（ADC）图高信号,大部分呈对称分布。其中2例ADC图显示在高信号范围内夹杂局限性低信号改变;2例患者在病灶中央区合并局灶性T1WI稍低信号,T2WI、Flair低信号改变。受累部位以双侧枕、顶叶最常见,其次为基底节、额叶、颞叶,少数累及小脑半球、脑干。部分患者短期内复查MRI完全恢复正常。结论：血管源性脑水肿是子癇患者主要的影像学改变;少数患者可合并细胞毒性脑水肿或脑出血;病变最常见累及后循环,多呈可逆性。     

可逆性后部脑病综合征MRI脑水肿与血清乳酸脱氢酶及脑钠肽的关系

目的探讨可逆性后部脑病综合征(PRES)患者的MRI影像学特点,进一步分析发病时患者脑水肿程度与血清乳酸脱氢酶(LDH)、脑钠肽(BNP)的关系。方法回顾性分析17例PRES患者的临床资料及MRI影像学特征,依据FLAIR、DWI及ADC图评价患者脑水肿类型及程度,分析脑水肿评分与LDH、BNP的相关性。结果MRI显示病灶多数较对称分布在顶、枕叶白质区,少数可累及额叶、基底节区、脑干。17例患者均符合血管源性水肿,其中4例合并细胞毒性水肿。患者血清LDH水平与脑水肿评分有显著相关性(r=0.575,P<0.05),而BNP与脑水肿评分无明显相关性(P>0.05)。结论PRES特征性MRI表现为双侧顶枕叶对称性血管源性水肿,但少数也可合并细胞毒性水肿,且血清LDH水平可作为评估患者脑水肿的参考指标。     

可逆性后部白质脑病综合征的临床及影像学特点

目的探讨可逆性后部白质脑病综合征(RPLS)的临床及影像学特点。方法回顾性分析16例RPLS患者的临床资料。结果患者均为急性起病,其中继发于高血压脑病7例,妊娠子痫9例。患者均出现血压明显升高,其中出现头痛9例,意识障碍9例,癫痫发作13例,视力模糊6例。16例患者MRI均表现为双侧枕叶和/或额、颞、顶叶对称或不对称的T1低信号,T2高信号;其中累及顶叶13例(81.3%),枕叶12例(75.0%),额叶9例(56.3%),颞叶5例(31.3%),小脑4例(25.0%)。弥散加权成像(DWI)显示等/低信号14例,异常高信号2例。所有患者经对症治疗均痊愈。结论 RPLS以血压升高、头痛、视觉异常、意识障碍、癫痫发作为主要临床表现。MRI表现双侧枕叶和/或额、颞、顶叶对称或不对称的T1低信号,T2高信号,经治疗预后良好。     

高血压脑病的CT和MRI表现

目的探讨头部电子计算机断层扫描（CT）和磁共振成像（MRI）对高血压脑病的诊断价值。方法回顾性分析32例高血压脑病患者的头部CT和MRI表现特点，并作文献复习。结果5例患者头部MRI发现异常，未发现头部CT异常患者。结论本病的头部影像学改变为水肿所致，常累及双侧顶、枕叶的应质下白质；MRI的诊断价值优于CT，且对本病的诊断和鉴别诊断方面具有重要意义。     

Diagnostic usefulness of diffusion-weighted magnetic resonance imaging in influenza-associated acute encephalopathy or encephalitis

A magnetic resonance imaging (MRI) study was performed for a 20-month-old girl with an influenza type A infection who presented acute encephalopathy. Conventional MRI performed 8 days after the onset of encephalopathy, including T1-weighted, T2-weighted, and fluid-attenuated inversion recovery imaging, revealed only vague lesions in the right frontal, temporal, and parietal lobes. In contrast, diffusion-weighted imaging (DWI) then demonstrated the lesions much more intensively. On the 26th day, the lesions previously observed on DWI had become less discernible. The hyperintensity observed on DWI might reflect cytotoxic edema. Thus, DWI may be useful for evaluation of acute influenzal encephalopathy/encephalitis.     

扩散加权成像诊断散发性Creutzfeldt-Jakob病价值

目的评价扩散加权成像(DWI)对散发性Creutzfeldt-Jakob病的临床诊断价值。方法回顾性分析21例临床诊断为很可能Creutzfeldt-Jakob病患者临床和MRI资料,总结其DWI特征。结果21例散发性Creutzfeldt-Jakob病患者DWI表现为大脑皮质"飘带"样高信号、尾状核和(或)豆状核高信号。异常信号发生部位以大脑皮质合并基底节区最常见(16例,76.19%),单纯皮质受累3例(14.29%)、单纯基底节区受累2例(9.52%);大脑皮质病灶中以额叶受累最常见(15例,78.95%),其次依次为顶叶(13例,68.42%)、颞叶(12例,63.16%)和枕叶(9例,47.37%)。与常规MRI相比,DWI显示病灶更清晰,病灶部位表观扩散系数值下降。21例中5例随访时,DWI高信号强度和范围有所变化,仅1例异常信号范围缩小。结论散发性Creutzfeldt-Jakob病的DWI表现具有一定特异性,推荐作为拟诊散发性Creutzfeldt-Jakob病的检查方法。     

Case of posterior reversible encephalopathy syndrome with cerebral vasoconstriction]

A 56-year-old woman attended our hospital because of acute severe (thunderclap) headache. Neurological examination was normal and no abnormality was found on head CT or by cerebrospinal fluid examination. A few days later, she experienced a recurrence and suffered a seizure in her left upper and lower extremities. On neurological examination, she had conjugate deviation of the eyes toward the right side and left lower limb paralysis with Chaddock sign. MRI showed multiple hyperintense lesions in the bilateral occipital and parietal lobes, predominantly in the subcortical white matter at the right side on T2-weighted and FLAIR images. We diagnosed posterior reversible encephalopathy syndrome (PRES) because the ADC map showed a vasogenic edema pattern (increased ADC values in the hypodense lesions on diffusion-weighted image). Her blood pressure was normal and there were no underling diseases. As MRA showed vasoconstriction especially in bilateral posterior cerebral arteries, we initiated a therapy with a Ca-channel blocker. On follow-up MRI, the hyperintense lesions on T2-weighted and FLAIR images had almost disappeared, and vasoconstriction was also improved on MRA. This case suggested that cerebral vasoconstriction could underlie both thunderclap headache and PRES.     

Reversible posterior encephalopathy syndrome: case report

The posterior reversible leukoencephalopathy syndrome (PRES) is a recently proposed cliniconeuroradiologic entity.The most common causes of PRES are hypertensive encephalopathy, eclampsia, cyclosporin A neurotoxicity and the uremic encephalopathies.Most patients are markedly hypertensive at presentation, although some have only mildly elevated or even normal blood pressure. Symptoms may include headache, nausea, vomiting, altered mental status, seizures,stupor, and visual disturbances. On CT and MR studies, edema has been reported in a relatively symmetrical pattern, typically in the subcortical white matter and occasionally in the cortex of the occipital and parietal lobes. These often striking imaging findings usually are resolved on follow-up studies obtained after appropriate therapy. Diffusion-weighted images would not show hyperintense signal because of the presence of interstitial rather than cytotoxic edema. We report a case of PRES due to hypertensive encephalopathy studied by CT and MRI.     

颅内表皮样囊肿20例

目的探讨颅内表皮样囊肿(EC)的临床与头颅MRI影像表现,以便提高诊断率。方法经手术病理证实的20例EC的MRI表现。全部患者均进行了常规平扫序列T_1WI、T_2WI、液体衰减反转恢复序列(FLAIR)及弥散加权成像(DWI)、钆对比剂增强扫描(CE-MRI)检查。结果 20例肿瘤脑桥小脑角池12例(左侧7例,右侧5例),桥前池3例,脑实质内2例(右侧枕叶1例,左侧额叶1例,病灶均发生于皮质区或皮质下区),左侧外侧裂池1例,枕大池1例,四脑室1例。其中4例病灶同时受累桥前池、鞍上池、侧裂池及环池等多个脑池间隙;全部病灶均呈囊性改变;13例长T_1WI、长T_2WI信号,4例T_1WI、T_2WI为混杂信号,3例T_1WI、T_2WI均为高信号;11例T_2FLAIR序列检查结果均呈混杂信号,其内可见散在的絮状稍高信号影,6例为低信号,3例为稍高信号;DWI序列检查结果为19例高信号,1例低信号。结论 EC的MRI表现具有特征性,尤其是FLAIR及DWI序列MRI表现有助于对该病的明确诊断。     

MRI-diffusion weighted images of encephalopathy associated with human herpesvirus 6 infection

Encephalopathy associated with human herpes virus 6 infection (HHV-6 encephalopathy) is not rare. The pathophysiology of HHV-6 encephalopathy has not been clearly established and diagnosis in the early stages is difficult. To elucidate the diagnostic value of MRI in the early stages of HHV-6 encephalopathy, we performed MRI including diffusion weighted imaging (DWI) on 6 patients. No abnormalities were found in the T1, T2 weighted images and fluid attenuated inversion recovery (FLAIR) images of any of the patients. DWI revealed an increase of signal in the subcortical white matter of the frontal lobes during the acute phase in all 6 patients. Follow-up MRI in two patients showed lesions expanded to the cortical regions, and disappearance of high signal-lesions followed by atrophy of the corresponding areas in 2 patients. To our knowledge, these findings have not previously been reported in acute encephalopathy and encephalitis and may be characteristic of HHV-6 encephalopathy. DWI may be a useful diagnostic procedure in the early stages of HHV-6 encephalopathy.