脊椎转移瘤的M砌诊断

目的同顾性分析脊椎转移瘤的MRI诊断特征及规律。方法本组20例患者,男16列、女4例,均先行MRI平扫,其中2例加增强扫描、2例加脂肪抑制序列扫描。结果胸椎受累8例,腰椎受累6例,颈椎受累1例,胸腰椎同时受累4例,颈胸椎同时受累1例;T1WI呈低信号14例,呈等信号6例;T2WI呈高信号12例,呈等信号6例,呈低信号2例。结论MRI对脊椎转移瘤的检出具有高度的敏感性;脊椎转移瘤多呈多发性、跳跃分布;脊椎转移瘤T1WI上多呈低信号或等信号,T2WI上信号不定,脂肪抑制序列呈高信号。     

胰腺癌的低磁场MRI表现

目的探讨低磁场MRI诊断胰腺癌的价值。方法回顾性分析我院78例经手术和病理证实的胰腺癌的MRI表现。结果肿瘤的低磁场MRI主要表现为胰腺出现局部软组织肿块或全部肿大，轮廓、信号异常，T1加权像呈等或低信号，信号不均匀，T2加权像信号不均匀增高；肝内外胆管、胰管扩张，邻近组织及器官受累。结论低磁场MRI能较好地显示胰腺癌的大小、形态和继发的胆、胰管梗阻、扩张以及肿瘤转移、侵袭范围，有利于肿瘤的诊断。     

无骨折脱位型急性颈脊髓损伤的MRI特点及意义

目的探讨无骨折脱位型急性颈脊髓损伤的MRI改变特点及其在脊髓损伤程度、预后及治疗中的作用。方法回顾性分析26例无骨折脱位型急性颈脊髓损伤的MRI和临床资料。结果无骨折脱位型急性颈脊髓损伤MRI绝大多数表现为脊髓水肿，急性期T1加权像等信号，T2加权像高信号。慢性期部分T1加权像局限性低信号，T2加权像局限性高信号。MRI T2加权像单节段脊髓水肿预后较双节段以上者好。结论无骨折脱位型急性颈脊髓损伤MRI信号改变及其范围能反映脊髓损伤程度，提示预后，指导治疗。     

青少年和成人脊柱嗜酸性肉芽肿的影像学表现

目的探讨青少年和成人脊柱嗜酸性肉芽肿(EG)在影像学表现的差异。方法分析21例手术后病理证实的脊柱EG,比较青少年和成人脊柱EG在X线平片、CT扫描和MRI影像上的差异。结果青少年脊柱EG具有典型X线片表现—扁平椎,成人不具有类似典型的表现;CT扫描青少年和成人类似,均表现为患椎椎体溶骨性破坏;MRI青少年和成人患椎T1加权像均表现为等信号,而T2加权像,青少年呈现等信号或中等信号增高,且相邻椎间盘呈现高信号改变。成人呈现高信号改变,患椎相邻椎间盘呈现高信号改变或中等信号。结论脊柱EG青少年X线平片具有典型改变,成人则无。CT、MRI可以显示病变侵犯椎体的程度和范围及脊髓损伤程度,从而决定治疗方式。     

强直性脊柱炎患者胸腰椎应力骨折的临床及影像学特点

目的:探讨强直性脊柱炎(ankylosing spondylitis,AS)患者胸腰椎应力骨折的临床及影像学特点.方法:8例AS患者发生胸腰椎应力骨折,男性5例,女性3例,年龄29～60岁,平均46.2岁.骨折部位:T9～T11 1例,T11～T12 3例,T12～L1 4例.对其临床表现和X线片、CT及MRI检查资料进行回顾性分析.结果:首发症状主要为腰背疼痛突然加重;主要症状为腰背部疼痛经过一段稳定期后突然加剧或为腰背部疼痛加重,呈持续性;查体均有骨折节段的压痛和叩击痛,6例伴胸腰椎后凸畸形;例患者脊髓功能Frankel分级为D级.X线片示8例均为胸腰椎应力骨折,骨折线经椎间隙,有假关节形成;检查示5例椎板骨折、椎间盘-椎体骨溶解及反应性硬化,1例可见椎体的骨皮质连续性中断、椎体破坏及溶骨性腔隙,2例可见椎体骨皮质连续性中断、椎板边缘不整及真空现象;榆查均有假关节节段不规则的低信号带延及后柱结构,其中6例表现为T1加权像低信号、T2加权像高信号,2例表现为T1加权像低信号、T2加权像低信号.结论:根据AS患者胸腰椎应力骨折的临床及影像特点,可以早期做出明确诊断.     

腰骶神经根囊肿的临床诊断和治疗探讨

目的：探讨腰骶神经根囊肿的临床诊断及治疗方法。方法：27例神经根囊肿患者，男17例，女10例，年龄42～65岁，平均53．6岁。其中有7例保守治疗，20例行手术治疗。手术中13例行囊肿大部分切除，残余部分缝合包绕囊内神经根；7例行囊肿大部分切除后用骶棘肌填塞交通孔。并对腰骶神经根囊肿的临床表现以及CT、脊髓造影、MRI等影像学资料进行分析。结果：CT扫描可见椎体后缘凹陷性压迹9例。脊髓造影显示神经根有囊状充盈11例。MRI显示囊肿在Tl加权像呈低信号，T2加权像呈高信号，信号与脑脊液一致。结论：MRI对本病诊断和鉴别诊断具有重要的临床价值；对保守治疗无效者，应行椎板开窗减压和囊肿摘除术。     

MRI诊断骨质疏松性椎体压缩性骨折所致椎体缺血性坏死

目的　评价MRI诊断骨质疏松性骨折所致椎体缺血性坏死的价值。方法　分析 7例骨质疏松性骨折椎体缺血性坏死的MRI表现。结果　矢状位MRI显示水平方向的带状区 ,T1加权像为低信号 ,T2 加权像为高信号 ,周围有低信号区包绕。结论　MRI检查可作为骨质疏松性骨折椎体缺血性坏死可靠的诊断依据     

颅骨巨细胞瘤的影像学诊断

目的分析颅骨骨巨细胞瘤的CT和MRI表现。方法收集8例经手术和病理证实的颅骨骨巨细胞瘤。全部病例均行CT和MRI检查(其中6例行增强CT检查,5例行增强MRI检查)。所有病例均行外科手术切除。术后2周,行放射治疗,剂量4500～6000cGy,时间为5～6周。结果CT显示不同程度的骨质破坏和钙化。大部分肿瘤边界清晰,MRIT1加权像呈低信号,T2加权像呈不均匀信号。T1加权像低信号区在T2加权像上随回波时间延长信号仍呈低信号而提示钙化。所有病例术后随访均无明显变化。结论CT能准确显示骨质破坏情况及钙化程度,MRI在显示病变的范围方面要优于CT,两者结合是诊断颅骨骨巨细胞瘤的最佳影像学检查方法。手术切除与术后放疗相结合是治疗颅骨骨巨细胞瘤较好的方法。     

MRI对骨质疏松性椎体压缩性骨折的诊断价值与转移性肿瘤所致椎体骨折的鉴别

目的:评价MRI对于骨质疏松性椎体骨折与转移性肿瘤所致椎体骨折的鉴别诊断价值.方法:分析76例老年人急性椎体骨折的MRI表现,其中原发性骨质疏松症56例,转移性肿瘤23例.共计T1、T2加权像114个椎体,Gd增强T1加权像36个椎体.结果:转移性肿瘤组表现为椎体后缘球形突出、椎体T1加权像呈弥漫性低信号、Gd增强像不均匀强化、椎弓根增大及不均匀强化、椎旁软组织肿块,与骨质疏松性骨折差异有显著性(P<0.05)或非常显著性(P<0.01).结论:MRI对于老年人良、恶性椎体骨折的鉴别具有十分重要的价值.     

椎间失稳致兔椎间盘退变磁共振影像计量分析

目的 :探讨由于椎间失稳诱发的椎间盘退变在磁共振成像 (magneticresonanceimaging ,MRI)中的表现。方法 :选用新西兰兔 15只 ,随机分为手术组 9只、对照组 6只 ,手术组沿L3～ 6棘突作后正中切口 ,剥离骶棘肌和关节突附丽肌肉 ,切除棘上、棘间韧带和关节突关节外后 1/ 2 ;对照组作相同皮肤切口即缝合。所有动物在标准条件下饲养 ,分别于术后 2、 4、 8个月行腰椎MRI检查及髓核信号值测量。结果 :术后 2～ 8个月 ,对照组腰椎未见异常 ,而手术组L3～ 6椎间盘则相继出现T2 加权像低信号、腰椎后凸畸形、T1加权像低信号、椎间盘后突和硬膜囊受压等改变。对手术组手术节段及其邻近节段椎间盘髓核信号值的定量分析显示 ,T2 加权像信号值减低在术后 2、 4、8个月均具有统计学意义 ,而T1加权像信号值减低在术后 8个月具有统计学意义 ;T2 信号值减低主要发生于术后 2个月 ,T1信号值减低发生于术后 8个月。结论 :脊柱失稳可诱发椎间盘退变。髓核T2 加权像低信号是椎间盘退变的早期和先发征象 ,T1加权像显示形态改变较好 ,但T1信号值在退变早期变化不明显。     

自发性脊柱硬膜外血肿的非典型MRI表现与鉴别诊断

目的 提高对自发性脊柱硬膜外血肿非典型MRI表现的认识.方法 对2000年至2008年来院的10例自发性脊柱硬膜外血肿非典型MRI表现进行分析,男7例,女3例;年龄12--64岁,平均32.1岁.所有病例均无明显的外伤史.常规行矢状位T1WI、T2WI,横轴位TwI,8例行增强扫描.结果 血肿呈梭形、椭圆形,位于脊髓的侧后方或后方的硬膜外腔.血肿发生于颈段5例,胸段3例,胸腰段2例.病灶与脊髓之间有一低信号线状影相隔,尤以T2WI显示最佳.血肿范围多在2～4个椎体,总量约5～10 ml,均值为(6.9±1.8)ml.在T1WI图像上,6例表现为等信号,4例表现为高信号;在T2WI图像上,6例表现为混杂高信号,4例表现为混杂低信号.5例血肿壁边缘轻度强化.6例血肿MRI信号比较典型.4例血肿MRI信号不典型.活动性出血以及血肿因时间而演变是血肿征象不典型的原因.本组4例误诊的原因:(1)活动性出血所致血肿征象不典型;(2)血肿位于狭窄的腔隙内;(3)临床上无外伤史.结论 根据血肿演变的规律,结合起病时间及可能存在活动性出血对血肿MRI信号进行分析,有利于对非典型血肿的诊断和鉴别诊断.     

Prognostic relevance of the postoperative evolution of intramedullary spinal cord changes in signal intensity on magnetic resonance imaging after anterior decompression for cervical spondylotic myelopathy

OBJECT: Areas of intramedullary signal intensity changes (hypointensity on T1-weighted magnetic resonance [MR] images and hyperintensity on T2-weighted MR images) in patients with cervical spondylotic myelopathy (CSM) have been described by several investigators. The role of postoperative evolution of these alterations is still not well known. METHODS: A total of 47 patients underwent MR imaging before and at the end of the surgical procedure (intraoperative MR imaging [iMRI]) for cervical spine decompression and fusion using an anterior approach. Imaging was performed with a 1.5-tesla scanner integrated with the operative room (BrainSuite). Patients were followed clinically and evaluated using the Japanese Orthopaedic Association (JOA) and Nurick scales and also underwent MR imaging 3 and 6 months after surgery. RESULTS: Preoperative MR imaging showed an alteration (from the normal) of the intramedullary signal in 37 (78.7%) of 47 cases. In 23 cases, signal changes were altered on both T1- and T2-weighted images, and in 14 cases only on T2-weighted images. In 12 (52.2%) of the 23 cases, regression of hyperintensity on T2-weighted imaging was observed postoperatively. In 4 (17.4%) of these 23 cases, regression of hyperintensity was observed during the iMRI at the end of surgery. Residual compression on postoperative iMRI was not detected in any patients. A nonsignificant correlation was observed between postoperative expansion of the transverse diameter of the spinal cord at the level of maximal compression and the postoperative JOA score and Nurick grade. A statistically significant correlation was observed between the surgical result and the length of a patient's clinical history. A significant correlation was also observed according to the preoperative presence of intramedullary signal alteration. The best results were found in patients without spinal cord changes of signal, acceptable results were observed in the presence of changes on T2-weighted imaging only, and the worst results were observed in patients with spinal cord signal changes on both Tl- and T2-weighted imaging. Finally, a statistically significant correlation was observed between patients with postoperative spinal cord signal change regression and better outcomes. CONCLUSIONS: Intramedullary spinal cord changes in signal intensity in patients with CSM can be reversible (hyperintensity on T2-weighted imaging) or nonreversible (hypointensity on T1-weighted imaging). The regression of areas of hyperintensity on T2-weighted imaging is associated with a better prognosis, whereas the T1-weighted hypointensity is an expression of irreversible damage and, therefore, the worst prognosis. The preliminary experience with this patient series appears to exclude a relationship between the time of signal intensity recovery and outcome of CSM.     

Brown-Séquard-plus syndrome due to stab injury: a case report

STUDY DESIGN: Case report. OBJECTIVE: To describe the mechanism of injury in this case and its clinical features. Magnetic resonance (MR) images of hemorrhage in spinal cord injury due to stab wound are discussed. METHODS: We describe the case of a 21-year-old woman who was stabbed in the right side of her neck and developed left-sided Brown-Séquard syndrome plus loss of bilateral proprioceptive sensation. Neither plain radiographs nor computed tomography of the cervical spine demonstrated any foreign bodies or fractures of the cervical spine. T2-weighted cervical MR images confirm spinal cord hemiresection at C5-C6. RESULTS: MR imaging was performed serially at 4 days, 4 weeks, and 8 weeks after trauma. The signal pattern of the spinal cord at the site of injury varied iso, iso, and low on T1-weighted consecutive images. Meanwhile, high signal intensity on T2-weighted images was consistent during the 8 weeks after incidence of trauma. A T2-weighted sagittal image showed a tiny spot of low intensity in the high signal band at the site of penetration, demonstrating hemosiderin formation in the spinal cord. The patient was treated conservatively and, recovered from Frankel grade C to grade D. CONCLUSION: Spinal cord injuries (SCI) following stab wounds are rare. MR imaging is definitely useful for recording and monitoring the pathology of SCI.     

Diagnosis and surgical treatment of spinal hemangioblastoma

Spinal hemangioblastoma is a rare tumor. Its incidence varies from 1.6 to 2.1% of primary spinal cord tumors. In this report, the authors described MRI (magnetic resonance imaging) of spinal hemangioblastoma and its surgical results. [MATERIALS AND METHODS] This series included 10 spinal hemangioblastomas studied with CT or MRI. There were 8 men and 2 women. The age ranged from 21 to 68 years, with a mean age of 45 years. 6 patients were preoperatively and postoperatively studied with a resistive 0.15 T system (Toshiba MRT 15A) or a superconductive 1.5 T system (GE Signa or Siemens Magnetom). The lesions were single in 8 out of 10 patients and multiple in 2. 10 spinal hemangioblastomas were located in intramedullary space and 2 in both intramedullary and extramedullary space. 8 out of 10 patients (80%) were associated with cyst. [RESULTS] (1) MRI In T1-weighted MR images after administration of Gd-DTPA, the solid component of the tumor enhanced brilliantly. The enhanced lesions contained serpiginous areas of signal void, reflecting vascular structures in 5 out of 6 cases. The intrinsic spinal cord signal was heterogenous with low intensity areas representing the associated cyst. The cyst appeared either isointensive to cerebrospinal fluid (CSF) or hyperintense relative to CSF and slightly hypointense relative to the spinal cord. The precise delineation of the tumor was impossible without enhancement. Noncontrast T1-weighted MR images displayed diffuse widening of the spinal cord. On T2-weighted MR images, all regions of the spinal cord enlargement increased in signal. (2) Postoperative results All 10 cases of spinal hemangioblastomas were totally removed with good postoperative results and the associated cysts were drained. The postoperative MRI showed the disappearance of the tumor and significant reduction in the size of the cyst. [CONCLUSION] (1) Gd-DTPA enhanced MRI was useful in defining and outlining the solid component of spinal hemangioblastoma. (2) The complete removal of the tumor with only drainage of the cyst was possible with good postoperative results.     

脊髓型颈椎病手术前后MRI的研究

目的：评价脊髓型颈椎病手术前后MRI表现及临床意义。方法：46例患者颈前路手术前后均行MRI的检查,按脊髓的受压程度及脊髓内信号改变分类,观察比较术前和术后MRI的变化与临床表现的关系。结果：脊髓受压程度与临床症状的严重程度密切相关,受压程度越重,临床表现越重（P＞0．05）,术后脊髓形态无恢复、髓内高信号未消失者术后恢复差。高信号消失或明显降低者术前症状轻,手术效果较好。结论：MRI对脊髓型颈椎病预后判断有重要意义。     

Multishot diffusion-weighted imaging features in spinal cord infarction

OBJECTIVE: The purpose of this study was to use a multishot, navigator-corrected, echo-planar (EP) pulse sequence to perform clinical diffusion-weighted imaging (DWI), analyze the DWI findings in ischemic spinal cord lesions, and discuss the value of DW magnetic resonance imaging (MRI) in distinguishing infarction (especially in the subacute stage) from inflammatory diseases and tumors of the spinal cord. METHODS: Six patients (two male, four female) with typical sudden onset of neurologic deficits caused by spinal cord ischemia were evaluated. There were no definite etiologies in these patients. Three cases occurred in the thoracolumbar region and three others occurred in the cervical cord. DWI was performed within 1-12 days after the initial neurologic symptoms by using a Philips Gyroscan 1.5 T MR system. Four patients had other scans including contrast-enhanced MRI and fluid-attenuated inversion recovery (FLAIR) scans. Two cases were followed up with MR images in 3 months. All the patients were imaged using a multishot, navigator-corrected, EP pulse sequence; apparent diffusion coefficient (ADC) values were calculated on the sagittal-oriented plane. RESULTS: MR abnormalities were demonstrated on sagittal T2-weighted images with "patch-like" or "strip-like" hyperintensities (six of six) and spinal cord enlargement (five of six). Axial T2-weighted images showed bilateral (six of six) hyperintensities. In one patient, only the posterior spinal artery territory was involved. The spinal cord was mainly affected at the cervical (three of six) and thoracolumbar (three of six) regions. Two cases involved the conus medullaris (T10-L1). The intensity of lesion signals in DW images depended on how soon after the onset of illness the scan was carried out and whether hemorrhage had occurred. In this group of patients, ADC values of lesions ranged from 0.23 x 10(-3) to 0.47 x 10(-3) mm2/s (average value 0.36 +/- 0.10 x 10(-3) mm2/s), markedly lower than the values of normal parts (average value 0.89 +/- 0.08 x 10(-3) mm2/s). There were obviously significant differences between areas with lesions and normal regions (P < 0.01). All cases had better signal contrast in DW images than in T2-weighted images. Dynamic or repeated DWI examinations may help analyze the degree of injury and recovery. Most lesions (three of four) showed nonenhanced effects in the contrast-enhanced MRI except one lesion, which showed irregular slight enhancement. FLAIR images showed poor signal contrast between lesions and normal tissue and thus are not fit for displaying infarct lesions. CONCLUSIONS: MRI is useful in detecting spinal cord infarction. DWI (especially multishot DWI) of the spinal cord may provide additional information for the assessment of ischemic changes and help improve in differentiating diagnosis.     

Cervical myelopathy due to OPLL: clinical evaluation by MRI and intraoperative spinal sonography

BACKGROUND: Concerning the relationship between morphology and clinical outcome, there have been many reports using computed tomography/myelography but not so many using axial magnetic resonance imaging (MRI) of the spinal cord. This is the first report to correlate axial cord image, intensity changes in MRI, and cord expansion pattern using intraoperative ultrasonography. OBJECTIVE: The objectives were to correlate MRI studies, axial cord images/expansion, and changes in MRI intensity to see if there is a direct prognostic significance to these changes and to determine whether preoperative axial MRI images of the spinal cord predict recovery from compressive myelopathy. METHODS: Posterior cervical decompressions with laminoplasty were performed in 44 patients with cervical myelopathy due to ossification of the posterior longitudinal ligament. On T2-weighted MR images, the cross-sectional shape of the cord at the level of maximal compression was categorized as boomerang, teardrop, or triangle. Additionally, with use of intraoperative ultrasonography, the expansion pattern of the cord that occurred intraoperatively was contrasted with that seen on postoperative MR images. RESULTS: Clinical recovery rates were the worst for those with triangular, intermediate for those with boomerang, and the best for those with teardrop shape. Preoperative low T1 and high T2 signals were found in most cases with triangular cord configurations. Triangular cord configurations showed the least expansion among the three categorized spinal cords. CONCLUSION: Patients with triangular deformity of the cord have atrophy as confirmed on MR studies where there is a low T1 and high T2 signal in the cord. Poor postoperative clinical recovery correlates with the lack of postoperative cord expansion on either MR or ultrasound evaluations. Those with either teardrop or boomerang deformities demonstrate a relatively good recovery rate.     

Increased MR signal intensity due to cervical myelopathy. Analysis of 29 surgical cases

The cases of 29 patients with cervical myelopathy, who had been treated by anterior spine fusion, were reviewed. The relationship between pre- and postoperative magnetic resonance (MR) images was investigated with special reference to increased signal intensity in the spinal cord on the T2-weighted images and the relevance of this finding to clinical conditions. Preoperatively, there were areas of increased signal intensity in 12 patients whereas there were no areas of increased signal intensity in the other 17. The lesions were not clearly demonstrated on T1-weighted images. The pre- and postoperative clinical condition of the patients whose preoperative MR images showed areas of increased signal intensity in the spinal cord on T2-weighted images was worse than that of the patients who did not have areas of increased signal intensity. Of the 12 patients with regions of increased signal intensity preoperatively, five showed decreased signal intensity postoperatively compared to the preoperative levels and seven had no change. The postoperative recovery of the five patients who showed decreased signal intensity postoperatively was better than that of the seven patients who exhibited no change. The areas of increased MR signal in the spinal cord might be due to edema, cord gliosis, demyelination, or microcavities.     

The value of T1-weighted coronal MRI scans in diagnosing occult fracture of the hip

A delay in establishing the diagnosis of an occult fracture of the hip that remains unrecognised after plain radiography can result in more complex treatment such as an arthroplasty being required. This might be avoided by earlier diagnosis using MRI. The aim of this study was to investigate the best MR imaging sequence for diagnosing such fractures. From a consecutive cohort of 771 patients admitted between 2003 and 2011 with a clinically suspected fracture of the hip, we retrospectively reviewed the MRI scans of the 35?patients who had no evidence of a fracture on their plain radiographs. In eight of these patients MR scanning excluded a fracture but the remaining 27 patients had an abnormal scan: one with a fracture of the pubic ramus, and in the other 26 a T(1)-weighted coronal MRI showed a hip fracture with 100% sensitivity. T(2)-weighted imaging was undertaken in 25?patients, in whom the diagnosis could not be established with this scanning sequence alone, giving a sensitivity of 84.0% for T(2)-weighted imaging. If there is a clinical suspicion of a hip fracture with normal radiographs, T(1)-weighted coronal MRI is the best sequence of images for identifying a fracture.