MR T2?mapping定量分析腰椎小关节退变关系研究

目的 探讨MR T2?mapping成像技术在定量分析腰椎小关节退变中的可行性及应用价值.方法 收集因慢性腰痛来本院就诊的患者51例及健康志愿者17例,采用3.0T MR对L1~S1腰椎小关节进行扫描,获取T2 WI及T2?mapping横断位图像,分别用于小关节形态学分级及关节软骨T2?值测定,行数据统计分析.结果 病例组与对照组小关节软骨T2?值差异无统计学意义(P>0.05);病例组不同Weishaupt分级的小关节软骨T2?值的单因素方差分析提示:0级与1级、0级与2级小关节软骨T2?值间均有显著性差异(P=0.001),0级与3级、1级与2级、1级与3级、2级与3级间小关节软骨T2?值间均无显著性差异(P>0.05).结论 MR T2?mapping成像技术在定量评价腰椎小关节早期退变中具有提示性价值.     

磁共振T2-mapping及T2*-mapping对兔腰椎间盘退变的定量研究

目的:探讨T2-mapping及T2*-mapping成像对椎间盘退变的诊断价值.方法:将30只新西兰大白兔随机分为正常对照组(15只)和糖尿病模型组(15只),两组中按时间(1月、3月、6月)随机各均分为3组.按分组时间对实验兔脊柱行T2 WI、T2-SPAIR、T2-mapping和T2*-mapping序列矢状面...     

MRI T1rho对无症状者腰椎间盘早期退变的评估价值

目的 探讨MR T1 rho对无症状志愿者腰椎间盘早期退变的评估价值,并分析T1 rho值与Pfirrmann等级、椎间盘不同解剖水平及性别的相关性.方法 对45例无症状大学生进行腰椎MRI检查,分别采集腰椎矢状位T1WI及T2WI、轴位T2WI、矢状位T1rho图像,按Pfirrmann分级标准在T2 WI图像上对无症状志愿者腰椎间盘进行等级分级,通过后处理软件在矢状位T1 rho上分别测量髓核(NP)和纤维环(AF)的T1 rho值,并分析其与Pfirrmann 等级、椎间盘不同解剖水平及性别的相关性.结果 腰椎间盘NP的T1rho值与Pfirrmann分级呈负相关(r=-0.63,P＜0.001),且各腰椎间盘NP区T1rho值明显高于AF(P＜0.001),但椎间盘各解剖节段的NP/AF区T1rho值未见明显差异,并且男女之间差异不大.结论 T1rho值与椎间盘退变等级密切相关,且对无症状志愿者椎间盘早期退变具有重要预测价值.     

DTI及T2 mapping对腰椎间盘退变的诊断价值

目的：探讨磁共振扩散张量成像(DTI)表观扩散系数(ADC)、各向异性分数(FA)以及 T2 mapping T2值定量评估腰椎间盘退变程度的价值。方法健康志愿者12例,男8例,女4例;慢性下腰痛患者28例,男15例,女13例;年龄19~70岁。行腰椎MRI矢状位T2 WI、DTI、T2 mapping成像。对 L1~S1椎间盘进行Pfirrminn退变分级,测量各腰椎间盘髓核 ADC 值、FA 值以及T2值并分析其与不同腰椎间盘退变分级的相关性,比较 ADC值、FA值以及T2值对腰椎间盘退变的诊断价值。结果腰椎间盘的平均ADC值、T2值与Pfirrminn分级呈显著负相关关系,相关系数分别为r=-0.779,r=-0.708(P<0.001);FA值与Pfirrminn分级呈正相关关系,但是相关关系不密切(相关系数r=0.474,P<0.001)。结论 DTI和T2 mapping可以定量评估腰椎间盘的退变程度,其诊断价值为 ADC 值最高,T2值次之,FA 值较差。     

磁共振T2弛豫时间和ADC评估腰椎间盘退变的对比研究

目的:探讨MRI定量测量T2弛豫时间和表观扩散系数(ADC)对腰椎间盘退变的诊断价值和临床意义.方法:46例无症状青年志愿者行腰椎常规MRI、T2-mapping和DWI检查.由两位医师分别对椎间盘进行Pfirrmann分级,并间隔一周2次测量髓核的T2值和ADC值.结果:同一观察者或不同观察者间测量的T2值和ADC值的一致性均较好(ICC=0.86～0.93,P＜0.01).髓核T2值及ADC值均与Pfirrmann分级呈负相关,但以T2值相关性更佳(rT2 =-0.70,P＜0.01;rADc=-0.60,P＜0.01).髓核T2值和ADC值在不同Pfirrmann分级之间的差异均有统计学意义(F=60.6和72.3,P＜0.01);各级间两两比较,T2值的差异均有统计学意义(P＜0.05).但ADC值在Pfirrmann Ⅰ级与Ⅱ级间的差异无统计学意义(P＞0.05).T2值和ADC值鉴别Ⅰ级与Ⅱ级、Ⅱ级与Ⅲ级、Ⅲ级与Ⅳ级椎间盘的ROC曲线下面积分别为0.86、0.92和0.80(P均＜0.01);0.69(P＜0.01)、0.90(P＜0.01)和0.74(P＜0.05).结论:T2值和ADC值均能定量评估腰椎间盘退变,二者相互结合能更全面地观察椎间盘早期退变的特征.     

基于mDIXON-Quant定量T2*值在腰椎间盘退行性变程度评估中的临床价值分析

目的探讨MRI mDIXON-Quant定量T₂^*值在腰椎间盘退行性变程度评估中的临床价值。方法在2019年3月~2019年11月招募年龄19~78岁,进行腰椎常规MRI及mDIXON-Quant检查,纳入标准且图像质量满意的共98例,平均年龄(42.2±17.1)岁。根据Pfirrmann标准将L₁/L₂~L₅/S₁椎间盘进行退行性变分级,并采用水-脂分离(mDIXON-Quant)技术定量测量相应椎间盘的T₂^*值。采用SPSS 19.0软件,运用一般线性方差t检验对不同检查者L₁~S₁椎间盘相应的T₂^*值与Pfirrmann分级进行比较,P<0.05为差异有统计学意义。用Pearson等级相关分析T₂^*与Pfirrmann分级的相关性,据相关系数r判断相关程度。结果L₁/L₂~L₅/S₁椎间盘在Pfirrmann分级与T₂^*值差异均有统计学意义(P<0.05)。分析L₁/L₂~L₅/S₁椎间盘在Pfirrmann分级与T₂^*值有相关性,L₁/L₂和L₂/L₃呈弱负相关,L₃/L₄呈强负相关,L₄/L₅和L₅/S₁呈中等程度的负相关。T₂^*值随着Ⅰ~Ⅴ组排序信号的变化呈现出下降趋势,尤其是Ⅱ~Ⅴ级的T₂^*值下降明显。结论基于MRI mDIXON-Quant序列T₂^*值定量评估腰椎间退行性变的程度不仅扫描时间短、重复性高、操作简便,尤其对下腰椎间盘退行性变的定量分析,不易受观察者主观因素的影响,可在一定程度上评估腰椎间盘退行性变。     

磁共振扩散峰度成像与T2 mapping成像对颈椎间盘退变的诊断价值

目的 探讨扩散峰度成像（DKI）、T₂ mapping成像定量参数对颈椎间盘退变程度的应用。方法 对临床因颈痛就诊的80例颈椎间盘退变患者行颈椎T₂WI、DKI及T₂ mapping定量成像扫描,按照Miyazaki分级进行颈椎间盘退变程度分类,对颈椎髓核的DKI定量参数值平均扩散系数（MD）、平均扩散峰度（MK）及T₂ mapping参数T₂值与Miyazaki分级、被检者性别和椎间盘形态的关系进行分析。结果 MD值与Miyazaki分级呈显著负相关（r=-0.850,P<0.01）,MK值与Miyazaki分级呈显著正相关（r=0.785,P<0.01）,T₂值与Miyazaki分级呈显著负相关（r=-0.851,P<0.01）。C_6/7节段T₂值（56.51±24.58）高于C_2/3（50.43±18.13）、C_3/4（49.96±17.51）、...     

腰椎间盘退变MRI分级系统的一致性评价

目的 评价腰椎间盘退变MRI不同分级系统的一致性.方法 40例腰背部疼痛和/或坐骨神经痛患者以及20例无症状志愿者,均行常规腰椎MRI平扫.基于矢状位T2WI,3名不同工作经验的影像诊断医师根据Pfirrmann's,Griffith's和Modified Pfirrmann's分级,分别独立评价300个腰椎间盘,每种分级均评价2次,每次间隔2～3周.采用Kappa检验,分别计算不同分级系统的组内及组间一致性.结果 3种方法的组内和组间Kappa值:Pfirrmann's分级组内一致性Kappa值0.781～0.845,组间一致性Kappa值0.651～0.791;Griffith's分级组内一致性Kappa值0.762～0.865,组间一致性Kappa值0.649～0.801;Modified Pfirrmann's分级组内一致性Kappa值0.795～0.890,组间一致性Kappa值0.695～0.822.结论 Modified Priffmann's分级系统是一个可重复的、一致性较高的方法,特别适用于评价早期腰椎间盘退变.     

MRI定量技术对椎间盘退变突出的临床应用研究

目的 应用MRI水脂分离技术(Dixon)联合T₂WI定量测量腰椎间盘水含量,分析椎间盘水含量与年龄、椎间盘高度、椎间盘退变、椎间盘突出及其诊断效能的相关性。方法 搜集77例因下腰痛进行腰椎MRI检查,在T₂-Dixon序列经过后处理测得椎间盘水含量,同时在T₂WI矢状位序列正中层面测量椎间盘高度,对比Pfirrmann(Pm)分级,分析各节段椎间盘水含量与年龄、椎间盘高度、椎间盘退变、椎间盘突出的相关性。结果 椎间盘水含量与Pm分级具有显著相关性,随着分级的增高,椎间盘含水量逐渐下降。将每个节段椎间盘水含量进行两两相比,下位椎间盘水含量低于上位椎间盘,差异有统计学意义(P<0.05)。L_4/5、L₅/S₁椎间盘的高度变化与椎间盘退变程度分级有关;且年龄与椎间盘水含量呈负相关。结论 常规的T₂-Dixon序列测量的椎间盘水含量与椎间盘退变存在显著的相关性,对椎间盘突出具有较敏感的诊断效能,且低位椎间盘变性程度更高。     

Quantitative T2 evaluation at 3.0T compared to morphological grading of the lumbar intervertebral disc: a standardized evaluation approach in patients with low back pain

Background

The purpose of our investigation was to compare quantitative T2 relaxation time measurement evaluation of lumbar intervertebral discs with morphological grading in young to middle-aged patients with low back pain, using a standardized region-of-interest evaluation approach.

Patients and methods

Three hundred thirty lumbar discs from 66 patients (mean age, 39 years) with low back pain were examined on a 3.0 T MR unit. Sagittal T1-FSE, sagittal, coronal, and axial T2-weighted FSE for morphological MRI, as well as a multi-echo spin-echo sequence for T2 mapping, were performed. Morphologically, all discs were classified according to Pfirrmann et al. Equally sized rectangular regions of interest (ROIs) for the annulus fibrosus were selected anteriorly and posteriorly in the outermost 20% of the disc. The space between was defined as the nucleus pulposus. To assess the reproducibility of this evaluation, inter- and intraobserver statistics were performed.

Results

The Pfirrmann scoring of 330 discs showed the following results: grade I: six discs (1.8%); grade II: 189 (57.3%); grade III: 96 (29.1%); grade IV: 38 (11.5%); and grade V: one (0.3%). The mean T2 values (in milliseconds) for the anterior and the posterior annulus, and the nucleus pulposus for the respective Pfirrmann groups were: I: 57/30/239; II: 44/67/129; III: 42/51/82; and IV: 42/44/56. The nucleus pulposus T2 values showed a stepwise decrease from Pfirrmann grade I to IV. The posterior annulus showed the highest T2 values in Pfirrmann group II, while the anterior annulus showed relatively constant T2 values in all Pfirrmann groups. The inter- and intraobserver analysis yielded intraclass correlation coefficients (ICC) for average measures in a range from 0.82 (anterior annulus) to 0.99 (nucleus).

Conclusions

Our standardized method of region-specific quantitative T2 relaxation time evaluation seems to be able to characterize different degrees of disc degeneration quantitatively. The reproducibility of our ROI measurements is sufficient to encourage the use of this method in future investigations, particularly for longitudinal studies.     

经皮椎体后凸成形术对邻近椎间盘退行性变的相关性分析

目的 探讨胸腰段椎体新近压缩性骨折经皮椎体后凸成形术(percutaneous kyphoplasty,PKP)后加剧相邻椎间盘退行性变的机制,比较术后不同时间椎间盘退行性变程度间的差异.方法 选取胸腰段新近压缩骨折患者PKP术65例患者临床资料,于术前后均有磁共振成像检查资料,分成术后随访时间≤12个月和＞12个月两...     

In vivo 3.0‐tesla magnetic resonance T1ρ and T2 relaxation mapping in subjects with intervertebral disc degeneration and clinical symptoms

The purpose of this study is (1) to determine the correlation between T_1ρ and T₂ and degenerative grade in intervertebral discs using in vivo 3.0‐T MRI, and (2) to determine the association between T_1ρ and T₂ and clinical findings as quantified by the SF‐36 Questionnaire and Oswestry Disability Index. Sixteen subjects participated in this study, and each completed SF‐36 and Oswestry Disability Index questionnaires. MRI T_1ρ and T₂ mapping was performed to determine T_1ρ (77 discs) and T₂ (44 discs) in the nucleus of the intervertebral disc, and T₂‐weighted images were acquired for Pfirrmann grading of disc degeneration. Pfirrmann grade was correlated with both T_1ρ (r = ?0.84; P < 0.01) and T₂ (r = ?0.61; P < 0.01). Mixed‐effects models demonstrate that only T_1ρ was associated with clinical questionnaires (R²_SF‐36 = 0.55, R²_O.D.I. = 0.56; P < 0.05). Although the averaged values of T_1ρ and T₂ were significantly correlated, they presented differences in spatial distribution and dynamic range, thus suggesting different sensitivities to tissue composition. This study suggests that T_1ρ may be sensitive to early degenerative changes (corroborating previous studies) and clinical symptoms in intervertebral disc degeneration. Magn Reson Med 63:1193–1200, 2010. © 2010 Wiley‐Liss, Inc.     

Assessment of intervertebral disc degeneration with magnetic resonance single‐voxel spectroscopy

This study examined the feasibility of using short‐echo water‐suppressed point‐resolved spectroscopy (PRESS) on a clinical 3T magnetic resonance (MR) scanner for evaluating biochemical changes in degenerated bovine and cadaveric human intervertebral discs. In bovine discs (N = 17), degeneration was induced with papain injections. Degeneration of human cadaveric discs (N = 27) was assessed using the Pfirrmann grading on T₂‐weighted images. Chemicals in the carbohydrate region (Carb), the choline head group (Cho), the N‐acetyl region (N‐acetyl), and the lipid and lactate region (Lac+Lip) were quantified using ¹H PRESS, and were compared between specimens with different degrees of degeneration. The correlation between the spectroscopic findings and glycosaminoglycan (GAG) quantification using biochemical assays was determined. Significant differences were found between the ratios (N‐acetyl/Cho, N‐acetyl/Lac+Lip) acquired before and after papain injection in bovine discs. For human cadaveric discs, significant differences in the ratios (N‐acetyl/Carb, N‐acetyl/Lac+Lip) were found between discs having high and low Pfirrmann scores. Significant correlations were found between N‐acetyl/Lac+Lip and GAG content in bovine discs (R = 0.77, P = 0.0007) and cadaveric discs (R = 0.83, P < 0.0001). Significant correlation between N‐acetyl/Cho and GAG content was also found in cadaver discs (R = 0.64, P = 0.0039). This study demonstrates for the first time that short‐echo PRESS on a clinical 3T MR scanner can be used to noninvasively and can reproducibly quantify metabolic changes associated with degeneration of intervertebral discs. Magn Reson Med, 2009. © 2009 Wiley‐Liss, Inc.     

腰椎间盘早期退变定量MRI研究的新进展

腰椎间盘退变引起的下腰痛是影响人们健康的重要原因,MRI 技术是诊断腰椎间盘退变的主要手段,特别是MR扩散加权成像、T2 mapping成像、T1ρ加权成像、钠MRI、软骨延迟钆增强MRI 和MR 波谱成像等新技术能够通过对蛋白聚糖、水等椎间盘细胞外基质成分进行检测,从而达到早期诊断腰椎间盘退行性变的目的。从上述几个方面综合论述MRI技术用于定量分析研究早期腰椎间盘退变的新进展,并就各自的优缺点进行比较。     

腰椎失稳致大鼠椎间盘蜕变的组织学和影像学观察

目的:建立大鼠椎间盘蜕变的动物模型,并对其组织学和影像学改变进行观察。方法:采用SD大鼠30只,手术对照组15只,手术模型组15只。后正中切口,剥离骶棘肌并向两侧分开,显露L1~6棘突,切除,暴露双侧椎板、关节突,咬除L1~6的小关节的外1/2部分,切断椎板间韧带;对照组仅行皮肤切开。X线检查大鼠腰椎的影像学改变,收集大鼠腰椎间盘组织,行HE染色观察组织学的表现。结果:手术模型组于术后3个月时出现椎间隙的楔形改变,于术后6个月时出现终板软骨的钙化和椎间隙的狭窄,术后9个月时则更为明显,同手术对照组相比有显著性差异(P<0.05);组织学改变于术后3个月时即可见髓核的皱缩,终板的轻度钙化,纤维环的排列不规则,术后6个月和9个月时可见髓核的纤维化,终板钙化明显纤维环板层状结构消失。结论:腰椎失稳可以引起大鼠的椎间盘的蜕变,为不直接损伤椎间盘组织建立椎间盘蜕变动物模型的好方法。