首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到19条相似文献,搜索用时 93 毫秒
1.
目的比较多发性硬化(MS)和视神经脊髓炎(NMO)视神经病变的MRI表现差异,探讨其在诊断及鉴别诊断中的价值。方法利用3.0 T磁共振仪对伴有视神经损害的20例MS患者及11例NMO患者行视神经MRI检查,比较MS和NMO视神经病灶断面分布位置,受累视神经的病变节段分布和视神经病变长度的差异。结果MS组视神经病灶周边型的发生率高于NMO,差异有统计学意义(P<0.05);NMO受累视神经管内段和颅内段病变发生率高于MS组,差异均有统计学意义(P<0.05);NMO组的视神经病变长度大于MS组,差异有统计学意义(P<0.05)。结论 MS与NMO视神经病变影像上存在明显的差异,视神经MRI在NMO与MS视神经病变的诊断及鉴别诊断方面有较大的临床价值。  相似文献   

2.
目的:探讨视神经肿瘤的MRI表现。方法:回顾了18例经MRI检查并经临床病理确诊的视神经肿瘤的病例。结果:视神经脑膜瘤8例,表现为视神经增粗1例,梭形肿块5例,软组织肿块2例。MR T1WI呈等或稍低信号,T2WI呈高信号。视神经胶质瘤6例,表现为视神经梭形增粗2例,椭圆形肿块4例,MR T1WI呈等信号,T2WI呈高信号。视神经转移瘤4例,3例为视网膜母细胞瘤累及视神经,MRI表现为眼球内病变侵犯视神经和视交叉,T1WI呈稍低信号,T2WI呈稍高信号;1例为乳腺癌转移至视神经,MRI表现为视神经椭圆形增粗,T1WI呈等信号,T2WI呈高低混杂信号。结论:MRI是检查和诊断视神经肿瘤的重要检查手段,对大多数病变可做出明确诊断。  相似文献   

3.
正常成人眶内段视神经的MRI测量研究   总被引:5,自引:0,他引:5  
目的 :评价正常成人视神经、视神经蛛网膜下腔的 MRI表现 ;通过测量视神经直径和蛛网膜下腔外径 ,建立正常标准。方法 :正常成人志愿受试者 42例 ,按性别和年龄 (18~ 40岁 ,41~ 6 0岁 ,6 0岁以上 )分组 ;采用 1.0 T MRI成像仪 ,环形激化圆形头颅线圈作眶内段视神经 MRI检查 ,应用 fs TSE- T2 加权序列 ,以斜矢状位为基准 ,垂直于视神经作斜冠状位扫描 ,扫描点位于球后 4mm、8mm和眶尖部。结果 :眶内段视神经不等粗 ,由前至后逐渐变细 ,前、后段直径分别为 2 .94± 0 .2 2 mm至 2 .2 4± 0 .2 4mm ,蛛网膜下腔外径不等宽 ,由前至后逐渐变窄 ,前、后段外径分别为 5 .2 5± 0 .2 4mm和 3.5 6± 0 .32 mm,蛛网膜下腔面积也逐渐变小 ,两径线比率则逐渐变大 ;性别和年龄组间无显著差异 (P>0 .0 5 )。结论 :MRI能准确显示视神经和蛛网膜下腔 ,测量结果与解剖学研究有良好的相关性 ,为视神经及蛛网膜下腔的评价提供了客观的定量指标 ,是视神经及相关病变较好的影像学检查方法  相似文献   

4.
视神经脊髓炎脑部异常的MRI表现及相关危险因素分析   总被引:2,自引:1,他引:1  
目的 分析视神经脊髓炎(NMO)脑部异常的MRI表现及特征,探讨脑内病灶发生的相关危险因素.方法 对符合2006年Wingerchuk诊断标准的54例NMO患者行脑部MR检查,分析脑部MRI异常患者病灶的分布及信号特点.采用Logistic回归分析评估脑内病灶发生的相关危险因素.结果 54例NMO患者脑部MRI正常24例(44.4%),MRI表现异常30例(55.6%),以多发的皮层下和皮髓质交界区白质小病灶最常见(13/30,43.3%).典型的NMO脑内病灶位于胼胝体、脑室室管膜下、下丘脑及脑干等部位,表现为斑点、斑片及线状异常信号.16例脑部增强检查均未见异常强化病灶.Logistic回归分析显示病程以及合并自身免疫病或前驱感染史与脑部MRI异常有关联(OR=3.519,P<0.05).结论 NMO患者脑部MRI出现异常信号较常见并有较特异的好发部位.合并系统性自身免疫病或有前驱感染史的NMO患者容易出现脑部MRI异常.
Abstract:
Objective To investigate the MRI features of the brain in patients with neuromyelitis optica (NMO), and to evaluate the correlation between the brain abnormalities and related risk factors.Methods Fifty-four patients with definite NMO according to 2006 Wingerchuk diagnosis criteria were enrolled in this study. MRI scanning of the brain was performed in these patients. Distribution and signalfeatures of all the lesions were analyzed. A Logistic regression analysis was used to evaluate the risk factors of brain abnormalities. Results Twenty-four NMO patients (44. 4%) showed unremarkable findings and thirty (55.6%) showed abnormalities on brain MRI. Multiple and non-specific small lesions in the subcortical white matter and grey-white matter junction were the most frequent abnormalities on brain MRI (13/30, 43. 3%). Typical lesion locations included corpus callosum, subependyma of ventricles,hypothalamus and brain stem. The lesions showed punctate, patchy and linear abnormal signals. Postcontrast MRI showed no abnormal enhancement in 16 cases. Logistic regression analysis showed that coexisting anto-immune disease or infection history had correlations with abnormalities of the brain on MRI (OR=3.519,P <0.05). Conclusions There was a high incidence of brain abnormalities in NMO.Subependymal white matter, corpus callosum, hypothalamus and brain stem were often involved in NMO.NMO patients with coexisting anto-immune disease and infection history had higher risk of brain abnormalities.  相似文献   

5.
前交叉韧带斜冠状面薄层解剖断面与MRI表现对照研究   总被引:5,自引:0,他引:5  
目的对冰冻膝关节前交叉韧带(ACL)斜冠状面薄层解剖断面与正常人膝关节MRI特点进行对照研究,为ACL损伤分级诊断建立基础。方法1例(1只)膝关节标本行斜冠状面MRI确定角度,冰冻后沿斜冠状面1mm层厚铣切,观察ACL薄层解剖特点。选择50名正常人对其ACL进行MR斜冠状面扫描,观察ACL的MRI特点。结果1只膝关节标本的ACL在斜冠状面薄层断面清晰显示其全程走行,清晰地显示ACL前内束与后外束,前内束从股骨髁附着点后上方区自后向外侧及前内侧走行,止于髁间棘附着区前内侧方,后外侧束从股骨髁附着点前下方区,自后外侧及外下走行,止于髁间棘附着区后外侧方。斜冠状面MRI能够显示50名正常人ACL全程,显示率为100%。MRI能够区分ACL前内束与后外束结构,显示前内束自后外侧向前内走行,止于髁间棘附着区前内侧方,后外束自后外侧向外下走行,止于髁间棘附着区后外侧方。MRI显示ACL走行与薄层断面显示的走行一致。结论斜冠状面是观察ACL的最佳方位,临床对怀疑ACL损伤的患者必要时行MR斜冠状面扫描。  相似文献   

6.
目的 :探讨眶内段视神经蛛网膜下腔扩张的MRI表现并评价其临床意义。方法 :回顾性分析 5 6例眶内段视神经蛛网膜下腔扩张的MRI图像。结果 :5 6例包括颅脑肿瘤 2 4例、颅脑外伤 11例、颅内出血 11例、颅内炎症 1例、脑积水 5例及良性颅内高压 4例。双侧眶内段视神经蛛网膜下腔扩张 5 5例 ,单侧扩张 1例。T2 WI等信号视神经周围扩张的蛛网膜下腔呈高信号影 ,在横轴位上呈“双轨征” ,在冠状位上呈“环形征”。眶内段视神经中点处蛛网膜下腔外径宽度为5 9mm± 0 .9mm。 34例肿瘤切除术后或内科治疗后复查 ,9例视神经蛛网膜下腔宽度无明显变化 ,7例扩张程度明显减轻 ,18例恢复正常。结论 :眶内段视神经蛛网膜下腔扩张提示颅内压增高 ,可作为临床评价颅内压增高的重要影像学依据。  相似文献   

7.
目的探讨盲人视神经的MRI和磁共振扩散张量成像(MR-DTI)特点。资料与方法对20例盲人进行视神经常规MRI和DTI扫描,并与20名正常健康者作对照。分别测量盲人和正常人双侧视神经的直径、各向异性(FA)值、平均扩散率(MD)值和水分子平行于纤维走行方向的扩散程度(λ∥)值、水分子垂直于纤维走行方向的扩散程度(λ⊥)值。统计分析采用独立样本t检验,检验水准α=0.05。结果(1)盲人视神经均明显变细、萎缩,在FA图和方向编码彩色(DEC)图上盲人视神经的信号强度较对照组明显降低;(2)盲人视神经的FA值(0.277±0.078)和λ∥值(1.808±0.307)较正常对照组明显降低,盲人视神经的MD值(1.442±0.264)和λ⊥值(1.231±0.225)较正常对照组明显升高,比较均有统计学意义(P均<0.001)。结论常规MRI仅能反映盲人视神经的形态学变化,而MR-DTI对视神经的信号变化非常敏感,并且可以定量反映盲人视神经萎缩后轴索和髓鞘的病理变化。  相似文献   

8.
垂体高度的断层解剖及MRI测量   总被引:3,自引:0,他引:3  
目的:通过尸体断层标本和MRI对照测量垂体的高度,为垂体的影像学诊断提供诊断标准、材料和方法:利用35例成人尸体断层标本,在各个断面上测量垂体的高度;在103例成人冠状头颅MRI上测量垂体的高度,并按年龄和性别分为十二组。将断层标本和MRI的测量数据进行比较。结果:在断层标本上测量垂体的平均高度为5.3±0.6(4.0-7.6)mm;MRI上的平均高度为5.4±1.3(4.0-8.3)mm。两组数据比较,无显著性差异(P>0.05)。男性垂体的平均高度为5.3±1.2(4.0-7.2)mm,女性垂体的平均高度为5.5±1.4(4.0-8.3)mm。女性垂体的平均高度大于男性。各年龄组比较显示,20岁以后,随年龄增长,垂体高度逐渐下降。结论:在MRI诊断中,垂体高度女性≥9mm,男性≥8mm可考虑垂体异常。垂体高度女性大于男性;20岁以后,随年龄增长,垂体高度有逐渐下降的趋势。  相似文献   

9.
目的 探讨DTI在视神经脊髓炎(NMO)患者视神经病变中的诊断价值.方法 选取28例NMO患者和38名健康志愿者进行视神经DTI扫描,并对视神经眶内段前部、中部及后部进行各向异性分数(FA值)测量.将NMO患者根据视力是否受损及视觉诱发电位(VEP)是否异常分为单眼受累组(10只眼)、双眼受累组(36只眼)及看似正常组(10只眼),所有患者进行扩展残疾状况量表(EDSS)评分.采用单因素方差分析、ROC曲线分析及Spearman相关分析,对各组间FA值及FA值与病程、EDSS评分等的相关性进行分析.结果 各组间FA值比较差异有统计学意义(F=43.54,P<0.01).其中,单眼受累组(0.29±0.08)、双眼受累组(0.27±0.08)及看似正常组视神经(0.35±0.13)FA值较正常对照组(0.45±0.07)减低,差异均有统计学意义(P值均<0.01),双眼受累组FA值较看似正常组FA值减低(P<0.01).ROC曲线分析显示正常对照组与单眼受累组、双眼受累组、看似正常组以及全部NMO患者组曲线下面积分别为0.92、0.95、0.74及0.91,其诊断视神经受损的敏感度分别为80%、86%、50%及79%,特异度均为95%.相关性分析显示FA值与NMO患者各组EDSS评分均无相关性,FA值与双眼受累组病程呈负相关(r=-0.371,P<0.05).结论 NMO患者视神经均存在不同程度的损害,视神经DTI可以简单有效地定量评估NMO患者视神经的损害.  相似文献   

10.
正常胃的MRI表现与扫描技术   总被引:1,自引:0,他引:1       下载免费PDF全文
目的:研究正常胃的MRI表现和扫描技术。方法:在胃不同充盈状态下,采用单次屏气快速扫描序列,共进行72人次MRI平扫和7次增强检查,分析正常胃的MRI表现和图像质量。结果:按充盈程度不同,胃壁形态可分为扩张不良,适度扩张、充分扩张3型表现。MRI能较好显示胃及其与邻近器官的关系。胃壁厚度平均值在适度扩张下为2.7mm,在充分扩张下为2.4.T2WI图像均无运动伪影,79%的T1WI图像在使用解痉剂后无运动伪影。结论:采用单次屏气快速扫描序列,MRI能获得满意的胃部图像,较好显示胃及其与邻近解剖关系。  相似文献   

11.
Measurements of the intraorbital optic nerve were made using high-resolution coronal MRI in 10 adults with autosomal dominant optic atrophy. Comparisons were made with previous studies of 10 normal adult subjects. The cross-sectional diameters of the optic nerve and the perineural subarachnoid space were measured and a ratio of there diameters at anterior, mid and posterior positions along the optic nerve was determined. We found a statistically significant difference in the mean optic nerve: sheath ratio between the control group and patients with autosomal dominant optic atrophy. At anterior, mid and posterior locations along the optic nerve it is significantly smaller in patients with optic atrophy. We have demonstrated that the loss of ganglion cells, previously documented in dominant optic atrophy, is associated with a significant loss of optic nerve tissue and thinning of the nerve along its length. Received: 6 July 1999/Accepted: 22 July 1999  相似文献   

12.
目的:探讨MRI对喉及下咽癌术前分期及术后评价中的临床应用价值。方法:26例喉及下咽癌患者(原发性肿瘤23例、术后复发3例)进行MRI扫描,分析其MRI表现,将结果与手术病理及CT扫描作比较。结果:MRI能较好地显示肿瘤的部位、大小及其侵犯范围。MRI对术前肿瘤分期及诊断颈部淋巴结转移的准确性为91%。高于CT扫描的87%及83%。结论:MRI扫描喉及下咽癌术前分期及术后评价有较大的帮助。  相似文献   

13.
视神经肿瘤的CT、MRI诊断   总被引:6,自引:2,他引:4  
目的 探讨视神经肿瘤的CT、MRI表现。方法 对病理学或临床证实的30例视神经肿瘤患者行CT、MR检查。结果 脑膜瘤17例,表现为视神经增粗3例,梭形肿块11例,不规则眶内肿块3例;CT为软组织密度;MR T1W1呈中等或低信号,T2W2呈中等或高信号;肿瘤钙化5例,肿瘤内“轨道征”10例,均有明显强化,累及管内段及颅内段3例,同时发现肿瘤有流空血管影5例。视神经胶质瘤8例,3例表现为视神经弥漫性增粗,5例表现为梭形肿块;CT为软组织密度;MR T1W1呈低信号,T2W2呈高信号,均明显强化;累及管内段、视交叉6例,2例伴发神经纤维瘤病。视神经转移瘤5例,4例为视网膜母细胞瘤侵及视神经,l例肺癌转移至视神经。结论 CT、MR检查不仅可以推测视神经肿瘤的性质,还可以明确肿瘤侵及范围,对临床诊断和治疗具有指导作用。  相似文献   

14.
MRI of the optic nerve in benign intracranial hypertension   总被引:2,自引:2,他引:0  
We investigated the MRI appearance of the optic nerve and its cerebrospinal-fluid-containing sheath in 17 patients with benign intracranial hypertension (BIH) and 15 normal controls. Using phased-array local coils, 3-mm coronal T2-weighted fat-suppressed fast spin-echo images were obtained with an in-plane resolution of < 0.39 mm. The optic nerve and its sheath were clearly differentiated. An enlarged, elongated subarachnoid space around the optic nerve was demonstrated in patients with BIH. High-resolution MRI of the optic nerve offers additional information which may be of value for diagnosis and in planning and monitoring treatment. Received: 12 February 1996 Accepted: 2 March 1996  相似文献   

15.
PURPOSE: To evaluate manganese (Mn2+)-enhanced MRI in a longitudinal study of normal and injured rat visual projections. MATERIALS AND METHODS: MRI was performed 24 hours after unilateral intravitreal injection of MnCl2 (150 nmol) into adult Fischer rats that were divided into four groups: 1) controls (N = 5), 2) dose-response (N = 10, 0.2-200 nmol), 3) time-response with repeated MRI during 24-168 hours post injection (N = 4), and 4) optic nerve crush (ONC) immediately preceding the MnCl2 injection (N = 7). Control and ONC animals were reinjected with MnCl2 20 days after the first injection, and MRI was performed 24 hours later. RESULTS: In the control group, the optic projection was visualized from the retina to the superior colliculus, with indications of transsynaptic transport to the cortex. There was a semilogarithmic relationship between the Mn2+ dose and Mn2+ enhancement from 4 to 200 nmol, and the enhancement decayed gradually to 0 by 168 hours. No Mn2+-enhanced signal was detected distal to the ON crush site. In the control group, similar enhancement was obtained after the first and second MnCl2 injections, while in the ONC group the enhancement proximal to the crush site was reduced 20 days post lesion (20 dpl). CONCLUSION: Mn2+-enhanced MRI is a viable method for temporospatial visualization of normal and injured ON in the adult rat. The observed reduction in the Mn2+ signal proximal to the ONC is probably a result of retrograde damage to the retinal ganglion cells, and not of Mn2+ toxicity.  相似文献   

16.
目的:探讨颅脑外伤患者眶内段视神经蛛网膜下腔扩张与颅内压增高的关系。方法:14例颅脑外伤并颅内压增高及蛛网膜下腔出血患者,在伤后2d内进行MRI检查,并在斜冠状位重T2加权图像上测量视神经球后4mm、10mm、16mm处蛛网膜下腔的外径,MRI检查结束后4h内进行腰穿,在施放脑脊液前测量脑脊液压力。经保守治疗6~14d,临床症状明显好转后,再重复一次MRI检查及腰穿脑脊液压力测定,对所得数据进行统计分析。结果:14例颅脑外伤并急性颅内压增高患者,首次检查脑脊液压力为2.31±0.24kPa,视神经眶内段前、中、后各测量点蛛网膜下腔的外径(左右侧平均值)分别为6.5±0.5mm、5.5±0.5mm、4.9±0.5mm,由前向后逐渐变窄(P<0.01)。经保守治疗好转后,脑脊液压力降低为1.75±0.21kPa,此时各测量点蛛网膜下腔外径分别为4.2±1.0mm、3.6±0.9mm、3.2±0.7mm,较首次检查明显变窄(P<0.01)。前、中、后各测量点的蛛网膜下腔的外径与脑脊液压力的相关系数分别为0.864、0.858、0.837(P<0.01)。结论:眶内段视神经蛛网膜下腔扩张程度与颅内压呈显著的正相关关系,可作为临床评价颅脑损伤患者颅内压增高程度的定量指标。  相似文献   

17.

Objective

To prospectively compare the renal safety of meglumine gadoterate (Gd-DOTA)-enhanced magnetic resonance imaging (MRI) to a control group (unenhanced MRI) in high-risk patients.

Methods

Patients with chronic kidney disease (CKD) scheduled for MRI procedures were screened. The primary endpoint was the percentage of patients with an elevation of serum creatinine levels, measured 72?±?24 h after the MRI procedure, by at least 25 % or 44.2 μmol/l (0.5 mg/dl) from baseline. A non-inferiority margin of the between-group difference was set at ?15 % for statistical analysis of the primary endpoint. Main secondary endpoints were the variation in serum creatinine and eGFR values between baseline and 72?±?24 h after MRI and the percentage of patients with a decrease in eGFR of at least 25 % from baseline. Patients were screened for signs of nephrogenic systemic fibrosis (NSF) at 3-month follow-up.

Results

Among the 114 evaluable patients, one (1.4 %) in the Gd-DOTA-MRI group and none in the control group met the criteria of the primary endpoint [Δ?=??1.4 %, 95%CI = (?7.9 %; 6.7 %)]. Non-inferiority was therefore demonstrated (P?=?0.001). No clinically significant differences were observed between groups for the secondary endpoints. No serious safety events (including NSF) were noted.

Conclusion

Meglumine gadoterate did not affect renal function and was a safe contrast agent in patients with CKD.

Key points

? Contrast-induced nephropathy (CIN) is a potential problem following gadolinium administration for MRI. ? Meglumine gadoterate (Gd-DOTA) appears safe, even in patients with chronic kidney disease. ? Gd-DOTA only caused a temporary creatinine level increase in 1/70 such patients. ? No case or sign of NSF was detected at 3-month follow-up.  相似文献   

18.
盛华强  赵斌 《医学影像学杂志》2006,16(10):1084-1087
目的:探讨MRI推断侵袭性垂体瘤质地、侵袭性的价值。方法:35例行MR检查侵袭性垂体瘤病人,测量T1WI及T2WI肿瘤信号与脑白质信号的比值和强化前后肿瘤T1WI信号强度比值,与其术中所见及术后病理对照,术中据肿瘤硬度分为质软、中等、硬;术后瘤体送检,结果进行统计学分析。结果:T2WI瘤体与白质信号比值与瘤体质地有明显相关性(P<0.01);MRI所示垂体瘤海绵窦及鞍周侵袭与术中及术后病理总符合率达85.3%。结论:MRI可以在术前准确预测侵袭性垂体瘤的质地、侵袭性。  相似文献   

19.

Objectives

To evaluate whether MR diffusion tensor imaging (DTI) of the optic nerve and optic radiation in glaucoma patients provides parameters to discriminate between mild and severe glaucoma and to determine whether DTI derived indices correlate with retinal nerve fibre layer (RNFL) thickness.

Methods

3-Tesla DTI was performed on 90 subjects (30 normal, 30 mild glaucoma and 30 severe glaucoma subjects) and the FA and MD of the optic nerve and optic radiation were measured. The categorisation into mild and severe glaucoma was done using the Hodapp–Parrish–Anderson (HPA) classification. RNFL thickness was also assessed on all subjects using OCT. Receiver operating characteristic (ROC) analysis and Spearman's correlation coefficient was carried out.

Results

FA and MD values in the optic nerve and optic radiation decreased and increased respectively as the disease progressed. FA at the optic nerve had the highest sensitivity (87%) and specificity (80%). FA values displayed the strongest correlation with RNFL thickness in the optic nerve (r = 0.684, p ≤ 0.001) while MD at the optic radiation showed the weakest correlation with RNFL thickness (r = −0.360, p ≤ 0.001).

Conclusions

The high sensitivity and specificity of DTI-derived FA values in the optic nerve and the strong correlation between DTI-FA and RNFL thickness suggest that these parameters could serve as indicators of disease severity.  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号