MRI在股骨头缺血坏死中的应用

为了确定ＭＲＩ对股骨头缺血坏死的诊断作用，尤其是在早期病变中的诊断价值，分析了１５例共２０个股骨头缺血坏死的ＭＲＩ，并与普通Ｘ线检查对比。结果发现ＭＲＩ在发现早期病变方面优于Ｘ线，ＳＴＩＲ（短时间反转回复）序列是发现早期病变的敏感序列。股骨头缺血坏死的ＭＲＩ表现为：（１）早期病变中央区Ｔ１ＷＩ高、Ｔ２ＷＩ中等信号；中期呈Ｔ１ＷＩ、Ｔ２ＷＩ高信号或Ｔ１ＷＩ低、Ｔ２ＷＩ高信号；晚期呈Ｔ１ＷＩ、Ｔ２ＷＩ低信号。（２）病变周围“双线征”。（３）软骨下骨折线。（４）关节积液。     

腰椎间盘变性时终板的MR信号分析

目的：探讨腰椎间盘变性时终板的ＭＲ改变。方法：使用自旋回波（ＳＥ）序列,矢状位Ｔ１ＷＩ,Ｔ２ＷＩ。观察７０例总共１１１个普性腰椎间盘的软骨终板信号改变的特征。结果：ＭＲＩ显示三种类 终板信号改变：１．Ｔ１ＷＩ低信号,Ｔ２ＷＩ高信号。２．Ｔ１ＷＩ、Ｔ２ＷＩ均呈低信号。３．Ｔ１ＷＩ高信号,Ｔ２ＷＩ等或稍高信号。结论：ＭＲ不仅可以软骨终在骨质硬化而产生的长Ｔ１、短Ｔ２信号,还可以显示因终板血管芽的纤维化     

后纵韧带骨化症的MRI初探

目的：探讨后纵韧带骨化症（ＯＰＬＬ）的磁共振成像（ＭＲＩ）信号特点及与病理的相关性。方法：４０例ＯＰＬＬ患者采用ＳＥ序列Ｔ１ＷＩ及快速小角度Ｔ２ＷＩ矢状面扫描，并于Ｔ２ＷＩ观察脊髓内信号强度的变化；９例行ＣＴ扫描。结果：骨化灶一般为无信号、信号不均。连续型９例，分节型９例，局限型１４例，混合型８例。骨化灶信号强度与病理的关系：高信号区为小骨髓腔，等信号区为新生小血管，低信号区为增生的纤维软骨，无信号区为骨细胞。Ｔ２ＷＩ脊髓内高信号９例。结论：ＭＲＩ不仅能显示骨化，还能了解骨化灶的组成成份，并能无损伤地观察脊髓受压的情况。对脊髓本身的变化可以得出病理水平的诊断。     

脑血吸虫病的MRI诊断

目的：探讨脑血吸虫病ＭＲＩ表现特点及诊断价值。方法：对９例经手术病理或临床证实的脑血吸虫病的ＭＲＩ资料进行回顾性分析。结果：（１）９例中,２例单发,７例多发,分布于顶颞枕叶皮层和皮层下区,其中２例同时见于小脑和脑干;（２）平扫：Ｔ１ＷＩ虫卵肉芽肿病灶为稍长Ｔ１略低信号,呈斑点状或结节状,同周围低信号水肿分界欠清;Ｔ２ＷＩ为等Ｔ２信号,常被水肿高信号掩盖;（３）Ｇｄ－ＤＴＰＡ增强扫描,病灶大多呈明显     

术后腰椎间盘炎的MRI诊断

目的：总结术后腰椎间盘炎的ＭＲＩ表现,以提高对本病的认识。方法：对１５例经病理和临床证实的术后腰椎音盘炎就ＭＲＩ表现进行了回顾性分析。结果：ＭＲＩ表现包括：（１）椎音隙变窄,以及邻近的椎体骨髓信号呈长Ｔ１长Ｔ２信号;（２）Ｔ２ＷＩ上髓核内低信号裂隙消失;（３）椎旁软组织肿胀;（４）ＭＲ增强后受累椎间隙和邻近椎体的信号明显增强。结论：ＭＲＩ能全面评价术后腰椎间盘炎,对其诊断有重要价值。     

颅内先天性表皮样囊肿的MRI诊断

为了探讨ＭＲＩ对颅内表皮样囊肿的诊断价值，观察了２０例经手术和病理证实的颅内先天性表皮样囊肿的ＭＲＩ表现，其中１２例有ＣＴ对照。Ｔ１加权像（Ｔ１ＷＩ）１８例呈低信号，其信号强度介于脑脊液和脑皮质之间，另２例呈明显高信号。Ｔ２加权像（Ｔ２ＷＩ）均呈高信号，但普遍有信号不均匀现象。１２例有ＣＴ者均呈低密度。颅内先天性表皮样囊肿好发于桥脑小脑角，有在中线生长的趋势，并常沿脑裂隙及脑池生长。ＭＲＩ显示病变范围优于ＣＴ，但对钙化的显示ＣＴ优于ＭＲＩ。结果提示：ＭＲＩ对颅内表皮样囊肿能作出定性诊断。     

小脑梗塞的MRI诊断及临床分析

目的：了解ＭＲＩ对小脑梗塞的诊断并结合临床进行分析。方法：对我院１６例病例行回顾性分析法。结果：小脑见Ｔ１ＷＩ呈长Ｔ１低信号，Ｔ２ＷＩ呈长Ｔ２高信号，边缘清楚光没，病灶无强化结论：ＭＲＩ对后颅窝病变，如小脑梗塞的诊断具有可靠性和准确性。     

脑血吸虫病的MRI诊断(附9例报告)

目的：探讨脑血吸虫病ＭＲＩ表现特点及诊断价值。方法：对９例经手术病理或临床证实的脑血吸虫病的ＭＲＩ资料进行回顾性分析。结果：（１）９例中,２例单发;７例多发,分布于顶颞枕叶皮层和皮层下区,其中２例同时见于小脑和脑干;（２）平扫：Ｔ１ＷＩ虫卵肉芽肿病灶为稍长Ｔ１略低信号,呈斑点状或结节状,同周围低信号水肿分界欠清;Ｔ２ＷＩ为等Ｔ２信号,常被水肿高信号掩盖;（３）Ｇｄ ＤＴＰＡ增强扫描,病灶大多呈明显均一强化;（４）灶周水肿较重而占位效应相对较轻;（５）吡喹酮驱虫治疗,病灶缩小,水肿消退。结论：结合病史与脑脊液血吸虫免疫学试验,ＭＲＩ是诊断本病的可靠方法。     

兔眼部植入物CT和MRI诊断

将硅胶带、硅胶海绵、人工晶状体、甲基纤维素和硅油置入４只兔的８眼内和眼球周围，探讨其ＣＴ和ＭＲＩ表现。植入物置入后２ｈ内完成ＣＴ和ＭＲＩ。ＭＲＩ选用ＳＥ序列Ｔ１ＷＩ、ＰＤＷＩ、Ｔ２ＷＩ和Ｆｌａｓｈ２ｄ序列。结果：３枚硅胶带和２枚人工晶状体ＣＴ未显示，ＭＲＩ呈低信号全部显示；３枚硅胶海绵ＣＴ显示低密度，ＭＲＩ呈低信号，均被检出；玻璃体内硅油ＣＴ呈高密度，Ｔ１ＷＩ和ＰＤＷＩ呈高信号，Ｔ２ＷＩ和Ｆｌａｓ     

兔眼玻璃体内生物组织异物CT和MRI诊断

将１０枚生物组织异物（巩膜、角膜、结膜、横纹肌和脂肪各２枚）分别置入５只兔的１０只眼玻璃体内，并与眼内积气、出血和青枝柳条对照，探索眼内生物组织异物的ＣＴ和ＭＲＩ表现。ＣＴ和ＭＲＩ在置入异物后２ｈ内完成。结果：巩膜、角膜、结膜和横纹肌ＣＴ图像上密度高于玻璃体，ＣＴ值４７～５２．５Ｈｕ。Ｔ１ＷＩ呈略高信号，Ｔ２ＷＩ和Ｆｌａｓｈ２ｄ序列呈低信号；脂肪呈脂肪性低密度，Ｔ１ＷＩ和ＰＤＷＩ呈明显高信号，Ｔ２ＷＩ和Ｆｌａｓｈ２ｄ序列呈相对低信号；８枚中４枚小于１．５ｍｍ×１ｍｍ×０．８ｍｍ的巩膜、角膜、结膜和横纹肌ＣＴ漏检；Ｔ１ＷＩ检出５枚，ＰＤＷＩ未显示１枚，Ｆｌａｓｈ２ｄ和Ｔ２ＷＩ全部检出。结果提示：ＭＲＩ检出眼内巩膜、角膜、结膜和横纹肌优于ＣＴ，ＳＥ序列、Ｔ２ＷＩ和Ｆｌａｓｈ２ｄ序列是检出这些组织的优选序列，但ＣＴ和ＭＲＩ不能分辨其组织类别，并且难与新鲜木异物区别；ＣＴ和ＭＲＩ联合应用能确定眼内脂肪性异物的性质，且能有效与眼内干木异物、积气和出血鉴别     

新生儿低血糖脑损伤的MRI表现及鉴别

目的探讨新生儿低血糖脑损伤的MRI表现及其与新生儿缺血缺氧性脑病的鉴别与联系。方法回顾性分析明确诊断为低血糖脑损伤的19例患儿的MRI表现及临床资料。结果 19例行DWI扫描均发现斑片状、条状及脑回样高信号,其中受累部位双侧顶枕叶皮层及皮层下白质18例,胼胝体受累9例,侧脑室旁脑白质受累5例,基底核受累2例,尾状核头部受累1例。常规MRI中6例内囊后肢T1加权高信号消失,5例因脑室周围及胼胝体压部出血表现为小片状短T1、短T2信号或短T1、长T2信号,3例表现为双侧顶枕叶皮层脑回样短T1及皮层下稍长T1信号,1例因双侧顶枕叶皮层及皮层下脑水肿表现为稍长T1、稍长T2信号。尚有3例同时伴有硬膜下血肿。3个月后2例复查MRI,均发现双侧顶枕叶多发软化灶。结论低血糖脑损伤多发生于大脑半球后部顶枕叶皮层及皮层下白质区,具有一定特征性,在临床中应引起重视,要结合临床病史及好发部位,以防误诊漏诊,造成严重后果。     

胼胝体原发颅脑恶性淋巴瘤的MRI诊断

目的:探讨胼胝体原发性颅脑恶性淋巴瘤的MRI表现特征。方法:回顾分析6例经手术病理或临床试验性治疗证实胼胝体原发性颅脑恶性淋巴瘤的MRI表现,并进行相关文献复习。结果:胼胝体原发性颅脑恶性淋巴瘤病灶多呈蝴蝶状、团块状及斑片状,可对称分布,肿瘤周围水肿较轻。T2WI多呈高及略高信号,T1WI呈低或略低信号。增强扫描多为中高度明显均匀强化,占位效应较轻。结论:胼胝体原发性颅脑恶性淋巴瘤MRI影像学表现具有一定的特征性,根据肿瘤生长部位、形态、信号及增强特征,有助于提高其诊断准确率,为临床治疗方案的制定提供可靠和客观的信息。     

新生儿低血糖脑损伤的磁共振表现及弥散加权成像优势

目的探讨新生儿低血糖脑损伤的核磁共振成像(MRI)表现及磁共振弥散加权成像技术(DWI)优势。方法回顾性分析临床诊断为低血糖脑损伤的19例患者的MRI和DWI表现。。结果 19例患者中,18例顶枕叶皮质及皮质下白质受累,9例胼胝体受累,6例内囊后肢高信号消失,5例侧脑室旁脑白质受累,2例基底节受累,1例尾状核头部受累。所有患者DWI均可见异常(100%),但仅有48.4%于常规MRI序列表现为阳性。3个月后2例复查MRI,均发现双侧顶枕叶多发软化灶。结论低血糖脑损伤最常见的发生部位是大脑半球后部顶枕叶皮质及皮质下白质区;DWI扫描可以发现早期的低血糖脑损伤,较常规MRI更为敏感。     

MRI of white matter pathways]

CT scan shows some relatively large white matter pathways such as corpus callosum or internal capsule, while MRI provides more sophisticated display of cerebral white matter pathways, based partly on difference in the water content, which improves contrast resolution of structures that cannot be appreciated on CT scanning. The white matter shows slightly high signal intensity in T1WI as compared with the peripheral gray matter. In contrast, it is relatively low signal intensity in long TR sequence. The signal intensity is correlated with myelination, density of myelin fibers and possibly iron deposition. In this study, we collected data on 30 patient, aged from 3 to 60 years average 38 years of normal MRI study of the brain. We routinely obtained T1 Weighted image (T1WI, TR/TE 500-600/20 msec), dual echoes image of proton density image (PDI, TR/TE 2000-3000/20 msec), T2 weighted image (T2WI, TR/TE 2000-3000/80-120 msec), in axial and coronal sections. In some cases sagittal section was also imaged. We identified the white matter pathways based on the data from the axial and coronal sections of 2 autopsy specimens. We also consulted several textbooks and literature reviews of gross and MRI anatomy. The following white matter pathways could be clearly observed on MRI: 1. Projection fibers: corona radiata and internal capsule; 2. Commissural fibers: corpus callosum and anterior commissure; 3. Associated fibers: superior occipito-frontal fasciculus, superior longitudinal fasciculus, ucinate fasciculus, cingulum bundle, optic radiation fornix and mammillothalamic tract.     

苯丙酮尿症研究十八年

将自1984年以来在中日友好医院开展的有关苯丙酮尿症(PKU)的主要研究工作总结如下：(1)1984年10月-2002年9月,共诊治苯丙酮尿症(PKU)患者603例。经新生儿筛查发现并在出生后3个月内开始治疗者136例,195例在3-12个月时就诊,272例1岁以上就诊。晚发现的467例PKU患者均有PKU的症状和体征,119例合并癫痫。经低苯丙氨酸饮食治疗,早治患者的智能和体格发育正常,晚治者的异常行为明显改善、智能也有不同程度提高。22个PKU家庭作了产前基因诊断,防止了第二胎患病胎儿的出生。(2)采用高效液相色谱仪(HPLC)对369例高苯丙氨酸血症(HPA)患者进行尿液喋呤测定,22例诊断为四氢生物喋呤(BH4)缺乏症。对18例BH4缺乏症患者及其家系进行基因分析,发现6种基因突变,其中259C→T和286G→A为中国北方人的常见突变。18例患者接受了BH4、L—多巴及5—羟色胺联合治疗,疗效满意。(3)未经治疗的PKU患者的脑电图(EEG)及颅脑磁共振成像(MRI)异常均具有高发生率。脑电图异常所见主要为痫样放电,少数为背景活动异常。颅脑MRI异常以T2WI上脑白质内散在斑片高信号灶最为常见,其次为脑髓鞘化发育延迟及脑发育不良。经低苯丙氨酸饮食治疗后,绝大多数患者脑电图及脑MRI随之改善。(4)将29例晚治的经典型PKU患者的基因型与治疗前的智能障碍程度作一比较,22例基因型与智力表型相符,7例不符,提示晚治PKU患者的基因型与其治疗前的智力表型有较好的一致性。     

急性一氧化碳中毒后迟发性脑病的临床表现、CT及MRI

目的 :探讨急性一氧化碳中毒后迟发性脑病 (DEACMP)患者的头部CT及磁共振成像 (MRI)改变的特点和诊断价值。方法 :分析 2 0例DEACMP患者的临床表现、CT及MRI资料。结果 :DEACMP患者的主要临床表现为智能、人格改变 ;头部CT的特征表现为双侧大脑白质弥漫性低密度改变 ,以两侧或单侧基底节区或苍白球区低密度改变最明显 ;MRI表现为脑室周围白质和半卵圆中心双侧对称的点状、斑片状或融合性病灶 ,T2 加权呈高信号 ,T1加权呈低信号 ,基底节或苍白球区呈慢性缺血性改变。偶见病灶主要位于大脑皮层。结论 :本病的诊断主要依靠病史、临床表现和影像学检查。头部MRI对本病的诊断、鉴别诊断明显优于CT     

Magnetic resonance imaging of severe, long-term, opiate-abuse patients without neurologic symptoms may show enlarged cerebrospinal spaces but no signs of brain pathology of vascular origin

BACKGROUND: Recreational drug abuse is one of the most important risk factors for stroke in young adults. Abuse of opiates may lead to severe acute neurologic problems due to ischemia or hemorrhage. In contrast, their minor effects on brain structures are not well established. We evaluated brain magnetic resonance images (MRI) of opiate-dependent subjects who had no major neurologic symptoms or psychiatric disorder. METHODS: Seventeen opiate-dependent patients and 17 controls underwent 1.5 T MRI. Any abnormalities in signal intensity of the brain were recorded. Areas of vermis, corpus callosum, and midline internal skull surface (MISS) were measured from midline sagittal slice. To evaluate size of cortical sulci, sylvian fissures, and ventricles, axial images were compared with standard sets of reference images. In addition, bifrontal and sylvian-fissure ratios were measured. RESULTS: Only one patient had a small subcortical post-traumatic lesion; otherwise, gray and white matter showed normal signal intensities. Opiate-dependent subjects had significantly wider sylvian fissures (p=0.008, Mann-Whitney U) and larger ventricles (p=0.04) than controls. Bifrontal and sylvian-fissure ratios were significantly higher in patient group than in controls (p=0.013 and p=0.005, respectively). CONCLUSIONS: No signs of brain pathology of vascular origin were found. From the clinical point of view, we want to emphasize that in the first acute neurologic attack of opiate-dependent patients, any abnormal signal intensity in MRI is most probably associated with the patient's current situation. Sylvian fissures and ventricles were wider in opiate-dependent subjects than in controls, which may be related to brain atrophy located especially in frontal and temporal lobes.     

Magnetic resonance imaging in hepatolenticular degeneration. Analysis of 9 cases.

Nine patients with biochemically proved Wilson's disease underwent magnetic resonance imaging (MRI) of the brain. Areas of abnormal signal, long T1 and long T2, caused by gliosis and edema were seen in the lenticula, thalami, caudatum, brain stem as well as in the dentate nuclei. The abnormalities were bilateral and symmetric. Asymmetric focal white matter lesions were noted in a few patients. Focal atrophies were seen in the head of caudatum. Symmetric cavitations were only seen in the lenticular nuclei. Acute progressive type (2 patients) was characterized by cavity formation, and chronic progressive type (7 patients) by gliosis, edema and focal atrophy.

     

急性型胼胝体变性的临床表现和影像学特点

目的：探讨急性型胼胝体变性（M BD ）的临床表现和影像学特点。方法对该院诊治的3例急性型M BD患者进行回顾性分析,包括临床表现、实验室检查、影像学检查（头颅CT、MRI）和随访结果。结果3例患者均急性起病,主要表现为意识障碍、精神异常、癫痫发作、谵妄性震颤、高热等;CT与MRI可见胼胝体膝部和压部病灶,CT示病灶为低密度,MRI表现为 T1WI等或低信号,T2WI高信号,液体衰减反转恢复序列高信号,弥散加权成像（DWI）高信号,ADC等或低信号;3例均伴发双侧大脑半球白质对称性病灶,1例出现脑桥臂对称性病灶,1例胼胝体膝部及体部出现类似“三明治”样改变。结论急性型M BD临床表现多样,无特异性,但具有特征性影像学表现。     

儿童胼胝体发育异常的磁共振成像影像分析及临床价值

目的探讨胼胝体发育不良的的磁共振影像表现及其临床价值。方法回顾性分析132例胼胝体发育不良的磁共振影像及临床资料。结果总结所有入组病例的MR图像征象,单纯胼胝体发育不良者40例,其中胼胝体完全未发育者2例,部分未发育者13例,胼胝体发育不良者11例,胼胝体部分发育不良者14例。单纯性胼胝体发育异常主要表现为胼胝体部分或完全发育不良,变薄,或者胼胝体部分或完全未发育。胼胝体发育异常伴其他脑发育异常者92例。除了单纯性胼胝体的结构或形态异常,还伴有包括侧脑室增大、三脑室扩大上移,脑积水,透明隔缺如或透明隔间腔,脑白质发育不良,灰白质异位、脑裂畸形、脑回发育畸形、颅骨发育畸形,先天性表皮样囊肿及脑肿瘤等。临床上,部分患儿无明显的症状和体征,重者主要表现为不同程度发育迟缓、癫痫。单纯性胼胝体发育异常的临床症状较伴有其他脑发育异常的轻。结论 MRI能够很好的显示胼胝体发育异常,并能对伴随的其他脑发育异常做出全面的评估。