低场磁共振成像在无骨折脱位型颈髓损伤诊治中的应用

目的探讨低场强磁共振成像(MRI)在无骨折脱位型颈髓损伤临床诊治中的应用。方法收集19例无骨折脱位的颈髓损伤患者的MRI表现、临床资料,总结MRI检查在无骨折脱位型脊髓损伤诊治中的重要性。结果本组病例中X线、CT检查均未见骨折脱位,有颈椎间盘突出及椎体后缘增生、后纵韧带骨化,黄韧带肥厚、小关节突增生所致椎管狭窄,颈髓前、后受压,其中:颈髓前方受压14例,颈髓后方受压5例,颈髓前后同时受压6例;颈髓损伤平面对应椎管狭窄、脊髓受压平面:颈3~4水平11例,颈4~5水平5例,颈5~6水平2例,有1例颈髓损伤平面不同于脊髓受压平面。MRI信号表现:脊髓肿胀、脊髓水肿、脊髓挫伤。结论 MRI检查是诊断无骨折脱位的脊髓损伤的最准确、最有效检查方法,为临床医师评估预后、制定合理的治疗方案,提供可靠依据。     

急性无骨折脱位型颈髓损伤的MRI诊断价值探讨

目的:探讨MRI对急性无骨折脱位型颈髓损伤的诊断价值.方法:回顾108例经X线和CT证实无骨折脱位型颈髓损伤的MRI表现,分析其影像特征.结果:无骨折脱位型颈髓损伤可累及颈髓任一平面,而以C<,4>、C<,5>椎体对应平面最多见(63.3%),其中广泛水肿型51例,出血水肿型19例,局限型38例.此外,24例共计38个椎体骨挫伤;85例183个椎间盘髓核突出,相应平面硬膜囊及脊髓受压,以C<,4/5>、C<,5/6>椎间盘突出多见(85.2%);17例可见前纵韧带增厚及水肿信号;32例可见颈后部软组织水肿信号.结论:MRI不但能够早期发现急性无骨折脱位型颈髓损伤,并且能够对脊髓损伤进行分类,同时能够发现韧带及肌肉损伤,在诊断、治疗及预后判断中均具有重要价值.     

无骨折脱位型颈髓损伤的MR研究

目的：研究无骨折脱位型颈髓损伤的MR检查价值。方法：对70例无骨折脱位型颈髓损伤患者的MR表现进行回顾性分析。结果：无骨折脱位型颈髓损伤多发生在C3-5节段，其病理改变以水肿为主，急性期MR表现为T1WI等信号，T2WI高信号，慢性期表现为T1WI低信号，T2WI高信号。结论：MR检查能发现无骨折脱位型颈髓损伤的细微病理改变。     

无骨折脱位型颈髓损伤的MRI分析

目的 :探讨无骨折脱位型颈髓损伤的发生机理、好发部位及MRI特点。材料和方法 :回顾性分析 43例无骨折脱位型颈髓损伤的MRI表现。结果 :共发现脊髓异常MR信号 46处 ,多位于C4-6水平 ,异常信号T1WI为低信号、等信号或高信号 ;T2WI为信号均匀或不均匀的高信号。结论 :MRI能显示脊髓损伤的范围和病理改变 ,明确脊髓损伤处有无突出椎间盘的持续性压迫。是无骨折脱位型颈髓损伤最好的检查方法     

无骨折脱位型颈髓损伤的MRI诊断

目的：探讨无骨折脱位颈髓损伤的ＭＲＩ特点及意义。方法：１０例无骨折脱位颈髓损伤的ＭＲＩ和临床资料，分析其受伤脊髓的位置、信号和外力特点及临床脊髓功能表现。结果：无骨折脱位颈髓损伤多发生在Ｃ３～４节段。ＭＲＩ的信号特点是急性期Ｔ１加权等信号，Ｔ２加权高信号；慢性期Ｔ１加权低信号、Ｔ２加权高信号，异常信号范围局限，多位于脊髓背侧。结论：ＭＲＩ能对无骨折脱位的颈髓损伤作出精细、正确的诊断，对其治疗和预后有指导意义     

膝关节Ⅴ型骨挫伤的MRI诊断及临床意义

目的 评价MRI对膝关节Ⅴ型骨挫伤的诊断价值及临床意义.方法 从1672例急性膝关节外伤的MRI资料中筛选出具有Ⅴ型骨挫伤的患者,分析其膝关节MRI表现.结果 Ⅴ型骨挫伤发生率2.6%(43/1672),表现为同时累及髌骨内下缘及股骨外髁前外缘的异常信号,在T_1WI上表现为低信号,在T_2WI上表现为等或稍高信号,在压脂PDWI上为高信号,在矢状面、冠状面及横断面上均可以敏感发现.MRI上显示骨折9例,软骨损伤29例,髌骨向外半脱位或脱位27例.髌骨内侧支持带损伤37例,在横断面上显示最佳并能进行分级.结论 MRI能准确显示膝关节Ⅴ型骨挫伤,对髌骨一过性脱位的诊断和治疗有重要意义.在MR检查中发现Ⅴ型骨挫伤时应加作髌骨横断面检查,以评估髌骨内侧支持带的损伤情况.     

慢性肩袖病变的MR特点——大体解剖和组织学对照研究

目的:与大体解剖和组织学对照,探讨慢性肩袖损伤的MR影像特点。材料和方法:采用Philips Gy- roscant 1.0-NT磁共振扫描仪。对20只人离体肩关节标本进行MR成像。结果:肌腱变性表现为T_1W/ PDW信号增高,无明显形态改变。依据组织学结果,我们将慢性肌腱部分撕裂分为三型:典型撕裂口(Ⅰ型)表现为肌腱撕裂口T_2WI水样高信号;瘢痕型(Ⅱ型)信号表现多样,常表现为T_2序列稍高信号伴肌腱显著增粗,多见于慢性肩袖损伤;肌腱内撕裂(Ⅲ型)与肌腱变性难以区分。肌腱完全撕裂包括"隧道征"、宽大裂口伴或不伴肌腱断端退缩三种表现。结论:慢性肩袖损伤尤其是肩袖部分撕裂的MR表现较为复杂,必须将信号和形态特点相结合慎重诊断。     

枕寰枢复合体创伤的影像学诊断

目的:探讨枕寰枢复合体(C_0-C_1-C_2)创伤的影像学诊断。方法:回顾性分析40例枕寰枢复合体创伤的X线、三维CT及MRI表现。结果:X线平片发现枕寰枢复合体骨折共15例,寰枢关节脱位7例,枢椎滑脱2例。三维CT发现枕寰枢复合体骨折28例,骨折合并寰枢关节脱位10例,寰枕关节半脱位5例,寰枢关节无骨折型脱位或半脱位8例。X线、CT检查阴性4例。MRI检查示28例枕寰枢骨折患者椎体有骨髓挫伤水肿表现,18例延髓或颈髓形态或信号异常,15例椎旁软组织及韧带损伤。结论:联合X线、三维CT及MRI诊断枕寰枢复合体创伤,可提高诊断准确性,为临床治疗提供依据。     

磁共振弥散张量成像在无骨折脱位型颈脊髓损伤的临床应用研究

目的 探讨磁共振弥散张量成像(MR-DTI)技术在无骨折脱位型颈脊髓损伤临床应用的可行性及其诊断价值.方法 收集病例组21例无骨折脱位型颈脊髓损伤患者和对照组27例健康志愿者行常规MR及MR-DTI检查,分别测定各向异性分数(fractional anisotropy,FA)值、表观弥散系数(apparent diffusion coefficient,ADC)值.结果 正常人颈髓MR-DTI的FA值=0.645±0.016,ADC值=(0.919±0.017)×10-3mm2/s.无骨折脱位型颈脊髓损伤MR-DTI的FA值=0.501±0.022,ADC值=(1.008±0.287)×10-3 mm2/s;与对照组对比:无骨折脱位型颈脊髓损伤中FA值明显降低,两者的差异具有统计学意义(P＜0.05),而ADC值略增高,两者的差异无统计学意义(P＞0.05).结论 DTI可以更加敏感的探测到无骨折脱位型颈脊髓损伤的发生,可为颈髓损伤程度的评估提供有价值的信息.     

急性颈髓损伤的高场强MRI信号特征及临床意义

目的探讨急性颈髓损伤后高场强MRI特征性表现,并分析其与临床神经功能相关性.材料和方法对54例急性颈髓损伤患者AsIA分级后行高场强MR成像,分析创区颈髓不同信号特点与神经功能缺失的相关性.结果28例颈髓损伤于T2wI表现为"环征"信号特点,其临床表现为脊髓完全损伤;26例MRI表现为长T1长T2信号变化,临床表现为脊髓不完全损伤,其损伤的长度反映出不同神经功能缺失,长度大于2.39±0.3cm,其神经功能缺失严重,长度小于0.84±0.05cm,神经功能损伤较轻.结论高场强MRI所表现不同信号特征可反映不同临床神经功能.     

Correlation of MR imaging findings with intraoperative findings after cervical spine trauma

BACKGROUND AND PURPOSE: There are limited data correlating MR imaging and anatomic findings of ligamentous injury in cervical spine trauma. This study compares acute MR imaging with surgical observations of disk/ligamentous injury after blunt cervical trauma. MATERIALS AND METHODS: Consecutive patients with acute cervical spine trauma who underwent preoperative MR imaging and surgery from 1998 to 2001 were identified. MR imaging was obtained within 48 hours of injury for most patients. All scans included sagittal T1, T2 fat-saturated, and short tau inversion recovery sequences. At surgery, extent of injury at the operated level was recorded on a standardized form for either anterior or posterior structures or both depending upon the operative approach. MR examinations were separately evaluated by 2 readers blinded to the intraoperative findings. Radiologic and surgical findings were then correlated. RESULTS: Of 31 patients, an anterior surgical approach was chosen in 17 patients and a posterior approach in 13 patients. In one patient anterior and posterior approaches were utilized. Seventy-one percent of patients had spinal cord injury on MR imaging. MR imaging was highly sensitive for injury to disk (93%), posterior longitudinal ligament (93%), and interspinous soft tissues (100%), but it was less sensitive for injury to the anterior longitudinal ligament (71%) and ligamentum flavum (67%). For most ligamentous structures, there was limited agreement between specific MR imaging findings and injury at surgery. CONCLUSION: In acute cervical spine trauma, MR imaging has moderate to high sensitivity for injury to specific ligamentous structures but limited agreement between specific MR imaging findings and injury at surgery. MR imaging may overestimate the extent of disruptive injury when compared with intraoperative findings, with potential clinical consequences.     

3.0T临床型MR多发性硬化大鼠脊髓成像的初步研究

目的：探索应用3.0T临床型MR设备进行多发性硬化（MS）大鼠脊髓成像的可行性。方法：用髓鞘少突胶质细胞糖蛋白多肽35-55（MOG35-55）致敏Lewis大鼠制备MS动物模型实验性自身免疫性脑脊髓炎（EAE）大鼠10只,正常对照组大鼠4只。3.0T临床型MR（Siemens Trio Tim）扫描仪配用正交腕关节线圈,行T2W、T1W和Gd-DTPA增强T1W的三维容积扫描,体素0.06-0.08mm3。结果：大鼠脊髓T2WI具有较高的空间分辨率,颈髓、胸髓和腰髓等节段显示清晰。脊髓灰质和白质的对比度较弱。MOG35-55-EAE大鼠病灶出现在颈髓和胸髓,矢状位重组图像显示病灶细节清晰,呈条片状,T2高信号,T1等信号,4个脊髓病灶均未见Gd-DTPA强化。结论：应用3.0T临床型MR扫描仪配备小正交腕关节线圈进行MOG35-55-EAE大鼠脊髓MR成像是可行的,为小动物脊髓疾病的活体体外监测提供了一种能广泛应用的无创性手段。     

颈椎前纵韧带断裂的早期MRI评估

目的:探讨急性颈椎创伤中前纵韧带断裂的早期MRI诊断.方法:经手术证实有43处前纵韧带断裂的25例急性颈椎外伤患者纳入研究,男21例,女4例,年龄35～75岁,平均54岁.采用1.5T磁共振成像仪,完成矢状面T<,1>WI(FSE)、T<,2>WI(FRFSE)和脂肪抑制(STIR)成像,层厚3～4mm.2名高级职称医师共同在线阅读MRI图像,以手术结果为参照、回顾性分析前纵韧带断裂及其前后相邻结构的MRI表现.结果:MRI共显示25例30个(30/43,69.8%,其中5例各见2个)颈椎前纵韧带断裂平面,其中25个显示韧带完伞断裂,矢状位上连续2～3个层面表现为粗线状异常信号改变,5个显示不完全断裂,矢状位上仅一个层面上表现为细线状或斑点状异常信号改变,异常信号表现为T<,1>WI上等信号、T<,2>WI上高信号、STIR上高信号.23例(23/25,92%)伴有椎前筋膜出血水肿,全部伴有椎间盘损伤(100%),4例患者(16%)见5处椎体前缘撕脱骨折或骨赘骨折,21例(84%)表现颈椎不稳.结论:急性颈椎创伤MRI早期检查有助于前纵韧带断裂的诊断,同时可以发现伴发改变.     

自发性脊髓硬膜外血肿的MRI诊断

目的 探讨自发性脊柱硬膜外血肿MRI表现特征.方法 对9例自发性脊髓硬膜外血肿的MRI表现作回顾性分析,本组患者均无明显的外伤史,发病后4～24h行MRI检查5例,1～3天行MRI检查3例,5天行MRI检查1例.常规横轴面、矢状面T2WI、TIWI及T2 WI脂肪抑制技术.结果 血肿发生于颈段4例,胸段2例,颈胸交界部2例,腰段1例.9例均表现为脊髓硬膜外梭形,长度7～12cm.血肿位于脊髓正后方4例,脊髓右后方3例,脊髓左后方1例,脊髓正前方1例,脊髓不同程度受压移位,脊髓与血肿间见线条状低信号影.4～24h行MRI检查5例,于T2 WI上呈稍高信号3例,高信号1例,等信号1例;于T11WI上呈等信号3例,等低信号2例.1～3天行MRI检查3例,于T2WI上呈低信号1例,等信号1例,等低信号1例;于T1WI上呈等信号2例,等低信号1例.5天行MRI检查1例,于T2 WI上呈低信号;T1WI上呈稍高信号.9例中T2WI压脂上呈低信号3例,等信号4例,高信号2例.结论 MRI是诊断自发性脊髓硬膜外血肿的最佳检查方法,不仅可以清楚地显示血肿的部位及范围,而且可以清楚地显示血肿新旧程度.     

Exclusion of unstable cervical spine injury in obtunded patients with blunt trauma: is MR imaging needed when multi-detector row CT findings are normal?

PURPOSE: To retrospectively determine what information, if any, magnetic resonance (MR) imaging of the cervical spine in obtunded and/or "unreliable" patients with blunt trauma adds to multi-detector row computed tomography (CT) of the entire cervical spine (including routine multiplanar sagittal and coronal reformations) when the CT findings are normal. MATERIALS AND METHODS: The study was HIPAA compliant and institutional review board approved. Informed consent was not required. From April 2001 to November 2003, 1400 trauma patients underwent MR imaging of the cervical spine to evaluate potential cervical spine injuries. Multi-detector row CT of the cervical spine was performed with a four- or 16-detector row scanner. MR imaging of the cervical spine was performed with transverse gradient-echo, sagittal intermediate-weighted, sagittal short inversion time inversion-recovery, and sagittal T1- and T2-weighted fast spin-echo sequences. Many MR examinations were performed to exclude soft-tissue injuries in the cervical spine of obtunded patients with blunt trauma in whom cervical spine injury could not be excluded with physical examination. Complete cervical spine MR studies were obtained to evaluate soft-tissue injuries in 366 obtunded patients with blunt trauma (281 male and 85 female patients; age range, 13-92 years; mean age, 42.1 years). The patients had previously undergone total cervical spine multi-detector row CT with normal findings. The results obtained with these two modalities were compared. RESULTS: MR images were negative for acute injury in 354 of the 366 patients and negative for cervical spine ligamentous injury in 362. Seven of the 366 patients had cervical cord contusions, four patients had ligamentous injuries, three patients had intervertebral disk edema, and one patient had a cord contusion, a ligamentous injury, and an intervertebral disk injury. Four patients had ligamentous injuries; however, all of these patients had ligament injuries limited to only one of the three columns of cervical spine ligament support. Multi-detector row CT had negative predictive values of 98.9% (362 of 366 patients) for ligament injury and 100% (366 of 366 patients) for unstable cervical spine injury. CONCLUSION: A normal multi-detector row CT scan of the total cervical spine in obtunded and/or "unreliable" patients with blunt trauma enabled the authors to exclude unstable injuries on the basis of findings at follow-up cervical spine MR imaging.     

MR imaging in radiation myelopathy.

PURPOSE: Using MR imaging, we assessed the signal, size, and enhancing characteristics of the cervical cord in patients in whom radiation myelopathy developed after radiotherapy for nasopharyngeal carcinoma. PATIENTS AND METHODS: Ten patients, 3 men and 7 women, aged from 32 to 77 years, were included. MR imaging was performed 1 to 53 months after clinical manifestations of myelopathy. RESULTS: Two cases showed atrophy of the cervical cord without abnormal signal intensity; in the others, a long segment of the cervical cord demonstrated low signal intensity on T1-weighted images and high signal intensity on T2- or T2*-weighted images. Some of these cases also showed swelling of the cord. Focal enhancement at C1-C2 area after intravenous administration of Gd-DTPA was seen in four cases. CONCLUSIONS: There is a correlation between the time of MR imaging after onset of symptoms and MR findings. When MR scans were obtained more than 3 years after onset of symptoms, atrophy of the cervical cord was noted without abnormal signal intensity. When MR was performed less than 8 months after onset of symptoms, a long segment of the cervical cord demonstrated abnormal signal intensity with or without associated swelling of the cord and focal enhancement.     

椎管内微小占位性病变的MRI诊断

目的:研究椎管内微小占位性病变的MRI特征及其对病变定性、定位诊断的意义。材料与方法:24例椎管内微小占位性病变患者(男12例,女12例,年龄23～67岁,平均29.1岁)均经PHILIPS 1.0NT型MR仪行常规T_1WI、T_2WI磁共振成像,其中6例又经Gd-DTPA增强扫描。全部病例的椎管内占位病变均经病理证实,并对其MRI表现进行了回顾性分析。结果:24例的病变经病理证实,18例为胚胎源性肿瘤(10例表皮样囊肿,4例皮样囊肿,4例畸胎瘤),4例为神经源性肿瘤(3例神经鞘瘤,1例神经纤维瘤),以及脊膜瘤与脂肪瘤各1例。各种占位性病变的MRI表现随其不同的组织学来源而有很大差别。表皮样囊肿多为均质长T_1长T_2信号。皮样囊肿以短T_1,长T_2信号为主。畸胎瘤呈混杂信号。神经鞘瘤为T_1WI低信号、T_2WI高信号,Gd-DTPA增强扫描后,囊壁均匀强化,偶见强化附壁结节。神经纤维瘤呈均质长T_1、长T_2信号,Gd-DTPA增强扫描后,病灶呈异常对比增强。脊膜瘤呈长T_1、稍长T_2信号,Gd-DTPA增强扫描后,病灶呈异常对比强化,并见局部硬脊膜增厚强化而形成的硬膜尾征。结论:各种病变的MRI表现随其组织学来源不同而有明显差异,它们在椎管内微小占位性病变的定性、定位诊断中起着重要作用,其诊断准确性优于X线椎管造影与CT。     

蜂蛰致中枢神经系统损伤的磁共振表现(附3例报告并文献复习)

目的探讨蜂蛰伤中枢神经系统损伤的磁共振影像表现及治疗后的影像转归。方法收集3例蜂蛰伤后出现中枢神经系统异常患者的临床及影像资料,3例均行头颅磁共振检查,经治疗后均行磁共振复查。结果2例表现为双侧基底核团对称性病变,在T1WI、T2WI上呈稍高信号,DWI呈高及稍高信号,其中1例合并双侧额顶枕叶皮层层状坏死,T1WI呈条状高信号;1例表现为右侧额顶颞枕叶、基底节区、侧脑室旁、左侧枕顶叶急性期脑梗塞;3例经治疗后临床症状好转,磁共振复查范围均较前减小,T1信号由高到低,T2信号由高到稍高,DWI由高到稍高。结论蜂蛰致中枢神经系统损伤可表现为双侧苍白球纹状体坏死、皮层层状坏死及脑梗塞等,影像表现有一定的特点,及时治疗后病变的MRI影像变化与临床症状好转相符。     

Acute spontaneous spinal epidural hematomas.

BACKGROUND AND PURPOSE: Although previous reports have characterized MR imaging features of spinal epidural hematomas (EDH), few cases have been reported during the acute or hyperacute phase within the first 48 hours. Our goal in this investigation was to correlate the MR imaging features of acute (< or =48 hours) spontaneous EDH with clinical management and outcome. METHODS: Eight patients with acute spontaneous EDH (five men and three women; age range, 31-81 years) underwent MR imaging at 1.5 T (T1-weighted, n = 8; T1-weighted after the administration of 0.1 mmol/kg contrast material, n = 6; T2-weighted, n = 8; and T2-weighted, n = 4). The interval from symptom onset to hospital admission ranged from immediate to 5 days. Two neuroradiologists reviewed the MR images for signal characteristics, contrast enhancement, and cord compression. Treatment and clinical outcome were correlated with the imaging findings. RESULTS: The EDH were located in the cervical (n = 3), cervicothoracic (n = 2), thoracolumbar (n = 2), and lumbar (n = 1) regions. On T1-weighted images, the signal intensity of the EDH was isointense to spinal cord in five cases, hyperintense in two cases, and hypointense in one case and did not correlate with time to imaging. Isointensity on T1-weighted images persisted for 5 days in one case. On T2-weighted images, all EDHs were hyperintense with focal, heterogeneous hypointensity. Cord compression was severe in six patients, moderate in one patient, and minimal in one patient. Four cases were treated conservatively with complete resolution or improvement of symptoms within 1 to 3 weeks. CONCLUSION: MR imaging findings were useful in establishing the diagnosis of EDH but did not influence management or predict outcome in this series. Heterogeneous hyperintensity to cord with focal hypointensity on T2-weighted images should suggest the diagnosis of acute spinal EDH. Severity of neurologic impairment had the greatest impact on management and outcome. Nonoperative treatment may be successful in cases with minimal neurologic deficits, despite cord compression revealed by MR imaging.