单个椎体压缩骨折：恶性和急性良性压缩骨折MR鉴别诊断

目的通过对31例单个椎体压缩骨折(包括恶性和由于骨质疏松造成的良性急性压缩骨折)的MR征象进行观察统计,鉴别其良恶性。方法31例单发椎体压缩骨折患者,其中恶性压缩骨折16例,良性急性压缩骨折15例。均通过活检及3～6个月随访观察证实。进行MR平扫(T1WI,T2WI)及增强扫描。结果单个椎体的恶性和急性良性压缩骨折的MR鉴别诊断主要通过形态学改变及增强后病变形态(共7个征象)进行分析。(1)急性良性压缩骨折椎体压缩程度大;病变不累及整个椎体;多数病灶沿终板分布,椎体前缘或后缘多正常或略凹陷,椎体后缘骨折可形成骨碎片后突;椎弓根多不受累;很少累及周围软组织;椎体静脉多清晰;典型强化方式为沿终板的带状强化。(2)恶性压缩骨折椎体压缩程度小;病变多侵及整个椎体;压缩后椎体前缘和/或后缘多向外凸;多侵及椎弓根;周围软组织受侵;椎体静脉多受侵显示不清;病灶多呈结节状强化。结论区分良性急性压缩骨折和恶性压缩骨折主要依靠形态学的改变和增强后病灶强化的形态,增强后信号增强程度对鉴别上述两种压缩骨折没有显著作用。     

MRI液体征象在良恶性椎体压缩骨折鉴别诊断中的价值

目的评价MRI液体征象在良、恶性椎体压缩骨折鉴别诊断中的价值。资料与方法回顾性分析200例椎体压缩骨折患者(压缩椎体296个)的MRI及临床资料,其中良性椎体压缩227个,恶性椎体压缩69个。卡方检验分析液体征象出现与骨折病因及椎体压缩程度是否相关。良、恶性椎体压缩骨折的诊断依据为穿刺活检,明确的影像表现,临床及MRI随访,有无明确肿瘤病史等。结果液体征象多位于邻近骨折的上、下终板缘,信号强度于T2WI及短恢复时间反转恢复序列(STIR)像上类似于脑脊液信号。良、恶性椎体压缩骨折出现液体征象分别为22%(51/227)和7%(5/69),经卡方检验两组之间差异有统计学意义(χ2=7.99,P=0.005)。在良性椎体压缩骨折中,液体征象出现与椎体压缩程度密切相关。组织学检查证实液体征象区为小碎骨片和纤维组织。结论MRI液体征象是良性椎体压缩骨折的特征性表现,可以此与恶性椎体压缩骨折鉴别。     

MRI在良、恶性椎体压缩骨折中的鉴别

压缩骨折指各种原因引起的椎体高度减小,病变椎体与相邻正常椎体相比,椎体高度减低至少 20%,轻微的形态及轮廓改变不包括在内。根据椎体压缩的程度分为 4级: 1级,椎体压缩度低于正常椎体的25%; 2级,椎体压缩度为正常椎体的 25% ~50%; 3级,椎体压缩度为正常椎体的 50% ~70%; 4级,椎体压缩度高于正常椎体的 75% [1]。恶性肿瘤引起的椎体压缩骨折为恶性压缩骨折,骨质疏松及外伤性压缩骨折为良性骨折。值得注意的是在有明确恶性肿瘤病史的患者,也常常发生椎体良性压缩骨折。有相当部分患者单纯表现为良性压缩骨折或单纯恶性压缩骨折,也有部…     

椎体压缩性骨折的磁共振诊断

目的分析椎体良、恶性压缩性骨折的MRI表现.材料和方法22例椎体良性压缩性骨折及49例病理性压缩性骨折患者,男43例,女28例,年龄34～76岁,平均58.3岁.全部行MR平扫+增强扫描.结果压缩椎体的信号改变对骨折甚为敏感,但对良、恶性骨折的鉴别缺乏特异性.压缩椎体残留有正常的骨髓信号者多见于良性骨折(P＜0.001).压缩椎体后缘膨出、椎管狭窄常见于病理性骨折(P＜0.001).椎弓根受侵(P＜0.001)及椎旁软组织肿块(P＜0.001)是病理性骨折所特有的征象.增强后椎体信号均匀与否对诊断有帮助(P＜0.001).结论病理性压缩性骨折多表现为椎弓根信号异常,椎体后缘明显膨隆,椎管狭窄,椎旁软组织肿块及增强后压缩椎体不均匀强化.椎弓根变形膨大一般不出现于良性骨折.     

MRI、CT对良恶性脊柱压缩骨折病因的诊断价值

目的 评价MRI、CT对良、恶性脊柱压缩骨折病因的鉴别诊断价值.方法 回顾性分析经临床确诊的脊柱压缩骨折64例86个椎体,外伤性压缩骨折15例18个椎体,老年骨质疏松性压缩骨折21例30个椎体,恶性压缩骨折28例38个椎体.MRI和CT分别重点观察了椎体信号或密度、椎体后缘形态、椎弓根及椎旁软组织形态、MRI增强的强化方式.结果 恶性压缩骨折28例38个椎体,较特异性的征象有:(1)椎体后缘呈球形凸出;(2)椎弓根膨大呈T2WI高信号;(3)T1WI呈广泛均匀低信号,且不均匀强化;(4)瘤样椎旁软组织肿块随强化时间延迟逐渐增大.良性压缩骨折36例48个椎体,较特异性的征象有:(1)椎体后上、下部分向后移位或成角;(2)骨折线下方盘状或带状低信号带;(3)T1WI部分正常骨髓信号保留,呈条带状均匀强化;(4)椎旁软组织块随强化时间延迟而吸收缩小.结论 MRI对恶性脊柱压缩骨折诊断具有较高的敏感性和特异性,CT对良性压缩骨折诊断具有明显的优势,二者联合检查,能明显地提高良、恶性脊柱压缩骨折病因的诊断符合率.     

椎体压缩性骨折的影像学诊断

目的探讨MR扫描对椎体原发性骨质疏松压缩性骨折及转移瘤所致的压缩性骨折的诊断及鉴别诊断的价值及表现。材料与方法对30例椎体原发性骨质疏松压缩性骨折和30例转移瘤压缩性骨折进行回顾性分析。结果椎体原发性骨质疏松性压缩骨折的特点椎体变形可分为楔形变、双凹形、扁平形,椎体后上角后突入椎管具有特异性;椎体信号特点椎体终板下或椎体中央带状T1WI低信号或椎体后部等信号外,椎体前部低信号,增强扫描后椎体信号强度与相邻正常椎体相同。转移瘤所致压缩性骨折的特点椎体后部皮质后突,T1WI上椎体内及椎弓根弥漫性低信号,增强扫描呈明显不均匀强化。结论增强扫描和非增强扫描的MR检查对椎体良恶性压缩骨折的鉴别有一定的价值。     

MR化学位移成像技术对脊柱压缩骨折病因的研究

目的:评价MR化学位移成像序列对脊柱压缩骨折病因的鉴别诊断价值.材料和方法:53例(共97个椎体)脊柱椎体压缩行MRI平扫和化学位移序列检查.其中病理性骨折31例(61个椎体,包括转移性肿瘤26例、骨髓瘤1例、结核4例);单纯性骨折22例36个椎体,包括单纯外伤所致15例,骨质疏松7例.病理性骨折者行CT导引下经皮骨穿刺检查或手术病理证实,部分临床证实;外伤或骨质疏松所致椎体压缩骨折均符合临床、实验室检查及MRI表现,部分随访证实.结果:快速梯度回波反相位序列上,41个病理性压缩椎体为高信号,20个椎体表现基本为等或稍低信号;而25个单纯性压缩椎体在快速梯度回波反相位序列上则表现为低信号,11个椎体表现为等或稍高信号,卡方检验P＞0.05.在快速梯度回波正相位序列上,压缩椎体基本上均为低信号.脊柱病理性骨折的反相位/正相位信号比是1.27 /-0.35,而良性压缩骨折反相位/正相位信号比是0.83 /-0.28,经统计分析P＜0.05.结论:化学位移序列在鉴别脊柱单纯性和病理性压缩骨折方面有较高的应用价值.     

DWI在鉴别脊椎良恶性病变中的应用价值

目的:探讨DWI在鉴别脊椎良恶性病变中的应用价值。方法:分析经病理和/(或)临床随访证实的脊柱压缩性骨折患者共50例82个病变椎体,其中良性组20例,34个椎体;恶性组30例,48个椎体。选取50例中的正常椎体35例共35节椎体作为对照组。均行MRI常规序列及DWI扫描;分析良恶性病变的DWI信号特点,并定量测定3组椎体的ADC值,进行统计学分析。结果:良性及恶性组病灶DWI序列均可表现为高、等、低或混杂信号,且2组信号表现差异无统计学意义;良性组、恶性组、对照组ADC值分别为(2.23±0.25)×10-3 mm2/s,(1.62±0.27)×10-3 mm2/s及(0.43±0.34)×10-3 mm2/s,经t检验,各组间ADC值差异均有统计学意义(P<0.05)。结论:DWI信号改变不能用于鉴别椎体良恶性病变,而ADC值具有重要的鉴别诊断价值。     

DWI在良、恶性椎体压缩骨折鉴别诊断中的应用

目的 :评价DWI在良、恶性椎体压缩骨折鉴别诊断中的应用价值。方法 :应用GE HDX 1.5 T超导MRI仪对169例患者的266个椎体行DWI和常规扫描,分别测量并计算ADC值。根据临床表现、影像学资料、病理结果将266个椎体分为正常椎体组33例33个椎体,良性压缩骨折组77例103个椎体(胸椎40个,腰椎63个),恶性压缩骨折组59例130个椎体(颈椎6个,胸椎50个,腰椎67个,骶椎7个)。对各组参数行F检验。结果:正常组ADC值平均为(0.616 0±0.380 7)×10-3mm2/s,良性组为(1.754 7±0.456 3)×10-3mm2/s,恶性组为(1.211 5±0.590 8)×10-3mm2/s。正常组、良性组、恶性组两两比较差异均有统计学意义。结论:正常组ADC值最小,恶性组次之,良性组最大,正常组、良性组、恶性组均有交叉。DWI对椎体的良、恶压缩骨折的鉴别诊断有一定价值。     

椎体良恶性压缩性骨折的MRI表现及其诊断

目的探讨脊椎良恶性压缩性骨折的MRI表现及其诊断.材料和方法回顾性分析171例201个椎体压缩性骨折的MRI表现,按良恶性病因分类.结果87%(71/82)恶性骨折无骨髓信号;83%(43/52)骨质疏松骨折完全保留骨髓信号."倒楔形”及"扁形”盘状压缩是恶性肿瘤压缩较典型表现."扁形”凹状压缩、椎体后上角突向椎管、T1WI椎体终板下带状低信号是椎体骨质疏松压缩的较典型表现.结合外伤史、发现骨折线、多伴骨髓信号改变为外伤骨折的诊断要点.结论MRI对良恶性脊椎压缩性骨折的诊断及鉴别诊断有较大意义.     

多发椎体压缩骨折良恶性MRI鉴别诊断

目的MRI鉴别多发椎体良恶性压缩骨折。方法171个椎体压缩骨折（良性77个、恶性94个）,16个经椎体活检,其余经3～6个月MRI追踪确诊。行T     

对良、恶性椎体压缩性骨折MRI鉴别诊断的再认识

目的：提高对椎体压缩性骨折定性征象的认识。方法：回顾性分析经临床确诊的椎体压缩性骨折56例78个椎体，外伤性骨折11例15个椎体；非外伤性骨折17例25个椎体；恶性压缩性骨折28例38个椎体，MRl分别重点观察了椎体骨髓信号、椎体后缘的形态、MRI增强的强化方式、椎弓根的形态及椎旁软组织的形态。结果：恶性压缩性骨折较特异性的MRI征象有：(1)L1WI像上椎体呈广泛均匀低信号；(2)椎体后缘呈球形凸出；(3)T2WI像上椎弓根膨大且可见高信号；(4)T2WI／I像受累椎体的不均一强化；(5)瘤样椎旁软组织肿块。结论：MRI的特征性改变能准确地鉴别良、恶性椎体压缩性骨折。     

Single shot fast spin echo diffusion-weighted MR imaging of the spine; Is it useful in differentiating malignant metastatic tumor infiltration from benign fracture edema?

PURPOSE: This study aims to evaluate the usefulness of single shot fast spin echo diffusion-weighted MR imaging (DWSSFSE) in differentiating malignant metastatic tumor infiltration of vertebral bone marrow from benign vertebral fracture edema. MATERIALS AND METHODS: Forty-six consecutive patients with 59 acute osteoporotic or traumatic vertebral fractures (mean age = 59) and 31 patients with 98 vertebral metastasis including 20 pathologic fractures (mean age = 53) were included in this study. Diffusion-weighted MR images were obtained by single-shot fast spin echo technique with diffusion gradient (b = 500 s/mm2, TR/TE: 5002/99) by using a 1.5 T MR scanner (Signa MR/i; GE Medical Systems, Milwaukee, WI, USA). T1- and T2-weighted images and short inversion time inversion-recovery (STIR) images were available in all 157 lesions, while contrast-enhanced images were available in 98 metastatic lesions. We evaluated signal intensity patterns on DWSSFSE in 157 lesions, which showed low signal intensity on T1-weighted images in both benign fractures and metastasis. The lesions on DWSSFSE were categorized as low, intermediate, and high signal intensity relative to presumed normal vertebra by concordant inspection of two experienced musculoskeletal radiologists. RESULTS: In benign fractures, DWSSFSE images showed low signal intensity in 56 vertebrae (95%) in 43 patients (93%) and intermediate signal intensity in only 3 vertebrae (5%) in 3 patients (7%). On the other hand, metastases most commonly had low signal intensity in 57 vertebrae (58%) in 25 patients (80%), intermediate signal intensity in 35 vertebrae (36%) in 16 patients (52%), and high signal intensity in 6 vertebrae (6%) in 3 patients (10%). Thus, intermediate and high signal intensities are far more common than benign fractures. Such differences in signal intensity were statistically significant (chi-square test, P < .05). High or intermediate signal intensity on DWSSFSE was highly specific for the diagnosis of metastatic tumor infiltration of the spine (sensitivity: 42%; specificity: 95%; true positive rate: 93%; false negative rate: 52%). CONCLUSIONS: DWSSFSE of the spine may be useful in differentiating metastatic tumor infiltration of vertebral bone marrow from benign fracture edema.     

MR多种成像技术在原发性骨质疏松椎体骨折鉴别诊断中的应用

目的 :探讨MR多种成像技术对鉴别原发性骨质疏松椎体骨折与其它原因所致病理性骨折的价值。方法 :对14例原发性骨质疏松椎体压缩骨折和 2 0例转移瘤所致骨折患者行MRI检查 ,成像序列均包括SET1 WI、FSET2 WI、STIR、DWI和增强SET1 WI抑脂序列 ,分析病变椎体在不同MR成像序列上的信号表现 ,计算病变区的强化比率、ADC值和骨髓对比率 ,进行统计学分析。结果 :SET1 WI、FSET2 WI、STIR和增强扫描上病变椎体横形分层样信号、椎体后上角后突及前后径增加、附件信号异常、邻近椎间盘信号增高、局部软组织肿块及椎管内结构受累在两组间发生率差异明显 ,骨质疏松骨折与转移瘤所致骨折的ADC值无显著性差异 (P >0 .0 5 ) ,两者强化比率和骨髓对比率有显著性差异 (P <0 .0 1)。结论 :MR多种成像技术联合应用对原发性骨质疏松椎体骨折与其它原因所致病理性骨折的鉴别可提供很大帮助     

MRI对椎体骨折的诊断价值

目的:探讨MRI对椎体压缩性(陈旧与新鲜)和隐匿性骨折的诊断价值。方法:对34例椎体骨折于初诊及伤后3,6,12个月行脊柱MRI检查,分析其信号改变与临床的关系。结果:37个骨折椎体急性期均表现为T1WI低信号、T2WI高信号,伤后3和6个月时分别有7个(18.9%)和22个骨折椎体(59.5%)恢复正常,12个月时全部恢复正常信号。伤后不同时期MRI检查结果相差十分显著。6个椎体陈旧骨折,与正常椎体信号无差别。8个隐匿性骨折椎体形态无异常,MRI T1WI、T2WI示椎体内横行条状低信号,3个月复查50%恢复正常,6个月复查基本恢复正常。结论:MRI能判断骨折修复的不同时期,鉴别椎体陈旧与新鲜骨折,尤其是存在多个椎体变形时则更具诊断价值;MRI检查对隐匿性骨折敏感。     

MR扩散加权平面回波成像对良恶性椎体骨折鉴别诊断的价值

目的　探讨单次激发平面回波SE序列扩散加权成像对良、恶性椎体压缩性骨折鉴别诊断的价值。资料与方法　对 46例 5 9个骨折椎体MR常规平扫后行扩散加权成像 ,良性组 2 7例 40个骨折椎体 ,恶性组 19例 19个骨折椎体 ,取b =0 ,2 0 0 ,40 0s/mm2 。测量病变椎体的信号强度比和信噪比。结果　在DWI上 ,良性骨折椎体与邻近正常椎体相比均呈低或等信号 ,恶性骨折椎体则呈高信号 ,2组骨折椎体的信号强度比和信噪比间存在显著差异(P <0 .0 1) ,诊断准确率 98%。而常规T1WI、T2 WI及STIR的误诊率达 6 .8%。结论　单次激发平面回波扩散加权成像对良、恶性椎体压缩性骨折的鉴别诊断是一种简便、有效的补充手段。     

CT and radiography of bacterial respiratory infections in AIDS patients

OBJECTIVE: Acute vertebral collapse is common, and it is sometimes difficult to determine whether the cause is benign or malignant. Recently, diffusion-weighted imaging has been reported to be useful for differentiating the two types. The purpose of this study was to evaluate diffusion abnormalities quantitatively in benign and malignant compression fractures using line scan diffusion-weighted imaging. SUBJECTS AND METHODS. Line scan diffusion-weighted imaging was prospectively performed in 17 patients with 20 acute vertebral compression fractures caused by osteoporosis or trauma, in 12 patients with 16 vertebral compression fractures caused by malignant tumors, and in 35 patients with 47 metastatic vertebrae without collapse. Images were obtained at b values of 5 and 1,000 sec/mm(2). The apparent diffusion coefficient (ADC) was measured in vertebral compression fractures and metastatic vertebrae without collapse. RESULTS: The ADC (mean +/- SD) was 1.21 +/- 0.17 x 10(-3) mm(2)/sec in benign compression fractures, 0.92 +/- 0.20 x 10(-3) mm(2)/sec in malignant compression fractures, and 0.83 +/- 0.17 x 10(-3) mm(2)/sec in metastatic vertebral lesions without collapse. The ADC was significantly higher in benign compression fractures than in malignant compression fractures (p < 0.01), although the two types showed considerable overlap. CONCLUSION: Although the quantitative assessment of vertebral diffusion provides additional information concerning compressed vertebrae, the benign and malignant compression fracture ADC values overlap considerably. Therefore, even a quantitative vertebral diffusion assessment may not always permit a clear distinction between benign and malignant compression fractures.     

Vertebral collapse model: combined diagnostic imaging

Ninety-eight consecutive patients with 344 collapsed vertebrae underwent conventional and/or digital radiography and MRI. Vertebral collapse was due to osteopenia (16 cases), trauma (17 cases), and vertebral osteonecrosis (3 cases). Other causes were: spondylodiscitis (9 patients), primary neoplasm (4 patients), metastases (37 patients), and hemomyelopathies (7 patients); 5 patients bore vertebral angiomas. Sixty-three patients also underwent CT and 25 bone scintigraphy. As far as collapsed vertebral endplates are concerned, according to a previous classification, outcomes were divided into 4 groups. Type 1 (focal concave collapse) was observed in 10% of benign lesions and in 1% of malignant ones; type 2 (diffuse concave collapse) in 24% of benign and in 16% of malignant lesions; type 3 (focal collapse with an acute angle) in 11% of benign and malignant lesions, and type 4 (diffuse collapse with an acute angle) in 11% of benign and in 26% of malignant lesions. Neural arch involvement was observed in 3% of benign lesions and in 16% of malignant ones; paravertebral soft-tissue involvement in 6% of benign and in 29% of malignant lesions; vertebral canal involvement in 11% of benign lesions and in 20% of malignant ones. The intervertebral disk proximal to vertebral collapse was more involved in benign lesions (24%) than in malignant ones (8%). MR signal followed 4 main patterns: low signal on T1-weighted images and high signal on proton-density and T2-weighted images (2% of benign lesions, 49% of malignant ones), low signal on all sequences (7% of benign lesions and 25% of malignant ones), isointense signal on all sequences (50% of benign and 21% of malignant lesions), and high signal on all sequences (41% of benign lesions and 0% of malignant ones).     

Vertebrae adjacent to spinal bone lesion are inconsistent reference markers: a magnetic resonance spectroscopic viewpoint

PURPOSE: To ascertain the suitability of vertebrae adjacent to spinal bone lesions as a signal intensity reference on MRI, and compare the MR spectroscopic appearance of vertebral body compression fractures due to malignant tumor infiltration, bone weakening (e.g., osteoporosis), and/or minor trauma. MATERIALS AND METHODS: Twenty-five patients with spinal compression fractures underwent routine spinal MRI with an additional 1H MRS study protocol to assess the percent fat fraction of the compressed vertebrae as well as the adjacent bony environment. Peak areas for water and total lipid were calculated from short-TE single-voxel 1H MR spectra using the LCModel analyzing tool. RESULTS: There were consistent water-only patterns in the fractured vertebra suggesting either near complete marrow replacement by malignant tissue or local edematous fluid/hemorrhage within the marrow spaces. However, the adjacent vertebrae showed a wide range of patterns from a dominant lipid signal to the inverse of a pronounced water level. These results far exceed the normal variation expected based on age and sex. CONCLUSION: The results suggest that the adjacent vertebrae may not be an accurate reference, especially in diffusion-weighted imaging (DWI), because of the large difference between the two compartments. Furthermore, in the case of gradient-echo measurements, the in-phase vs. opposed-phase effects are significant.     

Benign and malignant processes: normal values and differentiation with chemical shift MR imaging in vertebral marrow

PURPOSE: To establish retrospectively a range of values for signal intensity change in normal vertebral marrow by using chemical shift magnetic resonance (MR) imaging and to assess the use of this technique in differentiating benign from malignant marrow abnormalities. MATERIALS AND METHODS: Institutional Review Board approval for this retrospective, HIPAA-compliant study was obtained; informed consent was waived. A total of 569 normal vertebrae in 75 patients (42 women, 33 men; mean age, 57.5 years; age range, 26-84 years) (control group) and 221 lesions in 92 patients (50 women, 42 men; mean age, 59.0 years; age range, 27-85 years) (study group) who had focal vertebral marrow abnormalities were studied by using 1.5-T chemical shift MR imaging. Imaging time was less than 1 minute. The proportional change in signal intensity on in-phase compared with out-of-phase images was calculated by using 1 x 1-cm regions of interest (ROIs) in the control group and ROIs as large as possible for focal lesions in the study group. This change in signal intensity (expressed as a percentage) was compared with that of normal levels and benign and malignant lesions. For statistical analysis, a random effect model was used that was adjusted for multiple comparisons. RESULTS: A substantial decrease in signal intensity was noted for all normal vertebrae (mean, 58.5%) and for benign lesions, including endplate degeneration (mean, 52.2%), Schmorl nodes with edema (mean, 58.0%), hemangiomas (mean, 49.4%), and benign fractures (mean, 49.3%). Metastases exhibited either a minimal decrease or an increase in signal intensity (mean, 2.8%). Although there was some overlap in the range of signal intensity values among malignant lesions, benign lesions, and normal marrow, the differences in signal intensity loss for normal marrow and benign and malignant lesions were significant (P < .01 for all pairwise comparisons after adjusting for multiplicity). CONCLUSION: Bone marrow in the vertebral bodies displays somewhat variable behavior at chemical shift MR imaging. Results suggest that a decrease in signal intensity greater than 20% on out-of-phase images compared with in-phase images should be used as a cutoff threshold for normalcy to allow distinction between benign and malignant causes of vertebral marrow abnormalities.