MRS评估骨关节炎患者骨髓脂肪含量的变化

目的探讨氢质子磁共振波谱成像(MRS)评估绝经后女性髋部骨关节炎(OA)患者骨髓脂肪分数(FF)的变化。方法收集绝经后髋部骨关节炎患者(n=31)及健康对照组(n=22)行腰3椎体MRS检查及骨密度测定,计算骨髓FF。测定骨代谢标记物总I型前胶原氨基端肽(PINP)及骨吸收标志物I型胶原羧基端肽β(β-CTX)。结果 OA患者骨密度、PINP及β-CTX均高于正常对照组,差异有统计学意义。OA患者骨髓FF(58.5%±6.3%)较正常对照组(50.2%±5.2%)增高14.2%(t=2.411,P0.001),校正骨密度值,组间骨髓FF仍存在统计学差异。OA组及健康对照组骨髓FF均与骨密度(r分别为-0.532、-0.497,P均0.001)存在负相关性,但与PINP及β-CTX无线性相关性。结论绝经后髋部OA骨量虽然并未明显下降,但OA存在骨髓脂肪增多,提示OA存在骨脆性增高。     

~1H-MRS与DWI在骨质疏松症中的初步应用

目的 探讨绝经后女性腰椎骨髓脂肪分数(fat fraction,FF)、表观扩散系数(apparent diffusion coefficient,ADC)值与骨密度(bone mineral densities,BMD)的关系.资料与方法 将行腰椎双能量X线吸收测定(dual X-rayabsorptionmetry,DXA)的60例绝经后女性根据T值分为3组:骨质正常组(T>-1.0)20例,骨质减少组(T=-1.0～-2.5)20例,骨质疏松组(T<-2.5)20例.所有研究对象均行氢质子磁共振波谱分析(~1H MR spectroscopy,~1H-MRS)、MR扩散加权成像(diffusion weighted imaging,DWI),分别测定L_3椎体FF和ADC值.采用组间t检验对不同骨质组间FF、ADC值差异进行统计学分析.采用Pearson相关分析3组间FF、ADC值与BMD的相关性. 结果骨质疏松组脂肪含量[(59.1±8.8)%,P=0.003]与骨质减少组脂肪含量[(54±7.6)%,P=0.039]均比骨质正常组[(49±9.1)%]高.骨质疏松组比骨质减少组椎体脂肪含量高(P=0.045).椎体骨髓ADC值与T值无相关性.所有绝经后女性患者FF值与T值呈负相关(r=-0.46,P<0.01),与ADC值间呈轻度负相关(r=-0.25,P<0.05),但骨质疏松组中FF值与ADC值间呈较明显负相关(r=-0.72,P<0.01).ADC值与T值无相关性(r=0.315,P>0.05).结论 绝经女性椎体骨髓脂肪含量随着BMD的减小而增大.MRS可作为BMD检查的辅助手段.MRS与DWI可以无创性了解骨质疏松症患者骨髓的生理、病理变化,单纯DWI并不能反映BMD的改变.     

绝经后新诊断2型糖尿病腰椎骨髓脂肪成分的MRS测定

目的探讨磁共振波谱成像(MRS)用于定量绝经后新诊断2型糖尿病(T2DM)病人骨髓脂肪成分的变化,并分析其与糖化血红蛋白(HbA1C)的相关性。方法收集25例绝经后新诊断T2DM女性病人,年龄(57.4±4.5)岁,以25例健康女性作为对照者,年龄(56.6±4.0)岁。两组均行腰3椎体1H-MRS扫描,计算骨髓脂肪含量(FC)及不饱和脂肪指数(UFI)。测定被检者空腹血糖及HbA1C。采用独立样本t检验比较组间年龄、体质量指数(BMI)、血糖、HbA1C、FC及UFI差异,采用Pearson相关分析两组的FC、UFI与血糖及HbA1C的相关性。结果T2DM组骨髓FC值(63.2%±7.4%)与正常对照组(60.9%±6.9%)差异无统计学意义,但T2DM组骨髓UFI(6.1%±0.8%)较正常对照组(7.6%±0.9%)降低(t=-3.775,P0.001)。T2DM组HbA1C7.0%者的骨髓FC(66.0%±6.3%)高于HbA1C≤7.0%者(57.6%±6.5%)(t=2.893,P0.001)。T2DM组骨髓FC与HbA1C呈高度正相关(r=0.801,P0.001),而骨髓UFI与HbA1C水平呈负相关(r=-0.746,P0.001),但FC(r=0.226,P=0.206)和UFI(r=-0.184,P=0.589)与血糖无相关性。结论 T2DM病人腰椎骨髓FC可无明显变化,但UFI明显降低。T2DM骨髓脂肪成分与HbA1C密切相关,MRS测定骨髓脂肪组分可看作血糖控制程度的标志。     

磁共振波谱成像评估初发2型糖尿病患者骨髓脂肪含量

目的探讨磁共振波谱成像(MRS)定量评估初发2型糖尿病(T2DM)骨髓脂肪含量变化及其与胰岛素抵抗的相关性。方法初发T2DM患者及年龄匹配的正常对照组(n=32/组)行双能X线骨密度测定及股骨颈MRS扫描,分别获得骨密度(BMD)及骨髓脂肪分数(FF)。检查2组研究对象空腹血糖(FPG)、糖化血红蛋白(Hb A1c)、胰岛素(FINS)及血脂指标(TC、TG、HDL-C、LDL-C),利用稳态模式评估法评价胰岛素抵抗(HOMA-IR)。结果初发T2DM组BMD值与对照组无统计学差异。初发T2DM组FF值显著高于正常对照组(P0.001),校正糖代谢、脂代谢及BMD值,2组间FF值仍存在统计学差异(F值=16.763,P=0.012)。FF与HOMA-IR呈中度正相关性(r=0.683,P0.001),校正BMI,FF与HOMA-IR仍然存在正相关性(r=0.592,P=0.018)。结论初发T2DM患者骨髓脂肪增高,骨髓脂肪增多可能是胰岛素抵抗的影响因素之一。     

改良正反相位成像法对绝经后女性腰椎骨髓脂肪含量的评价

目的探讨MR多种正反相位成像法对绝经后女性腰椎骨髓脂肪含量的诊断效能。方法前瞻性选择绝经后女性56例,年龄55～83岁,平均年龄(62.8±4.02)岁。全部患者分别应用轻T_1权重正反相位法、重T_1权重正反相位法及三回波正反相位法分别扫描其腰椎,分析三种正反相位法腰椎骨髓脂肪分数比FF的均值;之后全部患者经双能X线骨质密度诊断仪扫描后分成骨量正常组(n=38)、骨量减少组(n=18);应用ROC曲线评价三种正反相位法的腰椎骨髓脂肪FF均值对绝经后女性骨量减少的诊断效能。结果 1)轻T_1权重正反相位法骨量减少组的FF均值大于骨量正常组(P0.05);年龄、体重对FF均值的影响有统计学意义(P=0.002;0.016);FF均值同年龄呈Pearson正相关(r=0.691,P=0.00),FF均值同体重呈Pearson负相关(r=-0.658,P=0.00);2)三回波正反相位法骨量减少组的FF均值大于骨量正常组(P0.05);年龄、体重对FF均值的影响有统计学意义(P=0.004;0.005);FF均值同年龄呈Pearson正相关(r=0.672,P=0.00),FF均值同体重呈Pearson负相关(r=-0.681,P=0.00);3)重T_1权重正反相位法骨量减少组同骨量正常组的FF均值无统计学意义(P=0.057);4)轻T_1权重正反相位法、三回波正反相位法的腰椎FF均值诊断绝经后女性骨量减少的ROC曲线下面积、诊断阈值、敏感度、特异度分别为0.852、0.871;0.3478、0.3663;81.6%、86.8%;77.8%、72.2%。重T_1权重正反相位法腰椎FF均值诊断绝经后女性骨量减少的ROC曲线下面积0.462。结论轻T_1权重正反相位法、三回波正反相位法的腰椎骨髓脂肪FF均值对绝经后女性腰椎骨髓脂肪含量的诊断有一定的效能。     

动态增强MRI评价去势兔骨质疏松腰椎骨髓灌注:与BMD和MVD对照研究

目的用MR动态增强观察去势兔骨质疏松腰椎的骨髓灌注变化,并与骨密度(BMD)、免疫组织化学对照。材料与方法新西兰大白兔22只,随机分为2组(实验组12只,对照组10只)。双侧卵巢切除术后3、5、7个月分别行动态增强MRI和双能X线吸收测量法(DEXA)检测腰椎骨髓灌注的最大增强百分比(Emax)、增强斜率(ES)和BMD,并与组织的微血管密度(MVD)对照。结果双侧卵巢切除去势法(OVX)组兔在术后7个月时腰椎BMD与对照组相比明显降低(P<0.05)。术后3个月和5个月两组间腰椎的Emax和ES值均无明显差异(P>0.05);术后第7个月OVX组腰椎的灌注较对照组明显下降,Emax和ES值均明显降低(P<0.05);对照组腰椎骨髓MVD计数平均为67.58±11.6;而OVX组的MVD计数为39.32±9.54,明显少于对照组(P<0.05)。OVX组兔术后7个月腰椎动态增强MRI的Emax、ES和组织的MVD呈正相关(r分别为0.866和0.771,P<0.05);Emax、ES和腰椎BMD之间亦有明显的正相关性(r分别为0.714和0.820,P<0.05)。结论去势兔骨质疏松后腰椎骨髓的血液灌注明显下...     

骨髓脂肪含量对预测骨质疏松性椎体骨折风险的初步应用

目的 探讨MRS骨髓脂肪含量对预测骨质疏松性椎体骨折风险的价值.方法 13例椎体骨折及19例无椎体骨折女性患者行双能X线吸收仪(DXA)检查,测定椎体骨密度(BMD)及MRS扫描计测L3椎体骨髓脂肪分数(FF),FF值对骨质疏松(OP)及OP性椎体骨折的诊断价值和临界值采用受试者工作特征曲线(ROC)来判断.结果 FF与BMD存在负相关 性,r=-0.527,P=0.002.FF判断DXA诊断的骨质疏松ROC曲线下面积为0.762,95%CI(59.4%～93.0%),敏感性78.6%,特异性61.1%.FF判断椎体骨折的ROC曲线下面积为0.819,95%CI(68.9%～94.9%),敏感性84.6%,特异性64.5%.结论 骨髓脂肪含量对预测OP性椎体骨折有潜在价值,为研究OP性骨折风险评估提供了一种新的思路.     

MRS动态评价骨质疏松模型兔骨髓质量变化规律

目的 MRS动态评价骨质疏松模型兔骨髓质量变化规律的可行性.方法 40只8月龄雌兔随机分为假手术组(A组,n=20)及去势+肌注半琥珀酸甲强龙组(B组,n=20).2组术后2、4、8、10周分别行L5椎体MRS扫描及血清骨代谢标记物检测.每组在每个时间点动物数5只.结果 术后2、4、8、10周A、B组骨髓脂肪分数(FF)分别为(41.20±4.85)%、(43.48±5.03)%、(45.10±4.61)%、(46.35±5.66)%和(46.20±5.24)%、(58.23±3.84)%、(64.39±5.53)%、(66.13±6.14)%.第4周开始,2组FF差异有统计学意义(P<0.01).结论 MRS可早期、无创性地动态评价骨质疏松骨髓质量,为研究骨质疏松骨髓发展变化规律及疗效评估提供了一种新的思路.     

胰腺导管腺癌患者具有较高的腰椎骨髓脂肪含量的影像研究

目的探讨胰腺导管腺癌腰椎骨髓脂肪含量的变化。方法收集32例经MDCT及病理组织学证实的胰腺导管腺癌患者(年龄41~76岁)及32例人口学匹配的健康受试者行MRI水-脂分离成像获取腰椎骨髓脂肪分数(FF),测定血糖、血脂指标(TC、TG、HDL-c、LDL-c)及胰岛素水平。多元Logistic回归分析胰腺导管腺癌的影响因子。结果胰腺导管腺癌患者FF(67.9%±7.8%)明显高于正常对照组(49.6%±6.5%),且组间血脂指标存在统计学意义(P均0.05)。Logistic回归分析发现,慢性胰腺炎史及FF是胰腺导管腺癌的危险因素,OR值分别为1.304(95%CI为1.102~1.780)及1.521(95%CI为1.115~2.004)(P均0.01)。结论胰腺导管腺癌患者具有较高腰椎骨髓脂肪含量。     

~1H MRS对椎体骨髓研究初步应用

目的 探讨椎体骨髓脂肪含量(fat fraction,FF)在不同年龄组、性别的变化规律及与骨密度(bone mineral densities,BMD)的相关性.方法 对85名年龄21～70岁健康志愿者及20名已行腰椎双能量X线吸收测定(dual X-ray absorptionmetry,DXA)诊断为骨质疏松的老年男女进行前瞻性MR波谱分析,测定L_3椎体脂肪分数值(fat fraction,FF).健康志愿者按每10岁为一个年龄段,将其分为5组,每组16～18人.结果 21～30岁组、31～40岁组、41～50岁组、51～60岁组、>60岁组和骨质疏松组的FF分别为30.7%±4.4%、35.5%±6.8%、41.9%士6.6%、46.8%±5.5%、51.7%±5.2%和59.2%±7.4%;除>60岁组和骨质疏松组外,各组L_3椎体脂肪含量男性均比女性高(P<0.05),其中,41～50岁组中的男女差别最大,达11.1%.骨质疏松组FF与BMD呈负相关关系(γ=-0.6,P<0.01).结论 正常椎体骨髓脂肪含量随年龄而逐渐增加,~1H MRS可作为评价骨质量的新手段.     

Rapid Increase in Marrow Fat Content and Decrease in Marrow Perfusion in Lumbar Vertebra Following Bilateral Oophorectomy: An MR Imaging-Based Prospective Longitudinal Study

ObjectiveBilateral oophorectomy leads to reduced bone mineral density (BMD), and reduced BMD is associated with increased marrow fat and reduced marrow perfusion. Purpose of this study was to investigate how soon these changes occur following surgical oophorectomy.ResultsReduced BMD, increased marrow FF, and reduced marrow perfusion occurred synchronously post-oophorectomy. There was a sharp decrease of 12.5 ± 7.2% in BMD (n = 6), a sharp increase of 92.2 ± 46.3% (n = 6) in FF, a sharp decrease of 23.6 ± 3.9% in maximum contrast enhancement (n = 5), and of 45.4 ± 7.7% for enhancement slope (n = 5) during the initial 3 months post surgery. BMD and marrow perfusion continued to decrease, and marrow FF continued to increase at a slower rate during the following 18 months. Friedman test showed a significant trend for these changes (p < 0.05).ConclusionBilateral oophorectomy leads to a rapid decrease in lumbar BMD, an increase in marrow fat content, and a decrease in marrow blood perfusion.     

Spinal multiparametric MRI and DEXA changes over time in men with prostate cancer treated with androgen deprivation therapy: a potential imaging biomarker of treatment toxicity

Objectives

To explore changes in bone mineral density (BMD) measured by DEXA and MRS fat fraction (FF), Dixon FF, and ADC in lower spinal vertebral bodies in men with prostate cancer treated with androgen deprivation therapy (ADT).

Methods

Twenty-eight men were enrolled onto a clinical trial. All received ADT. DEXA imaging was performed at baseline and 12 months. L-spine MRI was done at baseline and 6 months.

Results

The number of patients who underwent DEXA, Dixon, ADC, and MRS at baseline/follow-up were 28/27, 28/26, 28/26, and 22/20. An increase in FF was observed from T11 to S2 (average 1 %/vertebra). There was a positive correlation between baseline MRS FF and Dixon FF (r?=?0.85, p?<?0.0001) and a negative correlation between MRS FF and ADC (r?=?-0.56, p?=?0.036). Over 6 months, MRS FF increased by a median of 25 % in relative values (p?=?0.0003), Dixon FF increased (p?<?0.0001) and ADC values decreased (p?=?0.0014). Men with >5 % BMD loss after 1 year had triple the percentage increase in MRS FF at 6 months (61.1 % vs. 20.9 %, p?=?0.19).

Conclusions

Changes are observed on L-spine MRI after 6 months of ADT. Further investigation is warranted of MRS change as a potential predictive biomarker for later BMD loss.

Key Points

? Spinal marrow fat fraction increases after 6 months of androgen deprivation therapy. ? More inferior vertebral bodies tend to have higher fat fractions. ? MRS fat fraction changes were associated with later changes in DEXA BMD.

     

Gender and age groups interactions in the quantification of bone marrow fat content in lumbar spine using 3T MR spectroscopy: A multivariate analysis of covariance (Mancova)

Introduction

There is an age-related conversion of red to yellow bone marrow in the axial skeleton, with a gender-related difference less well established. Our purpose was to clarify the variability of bone marrow fat fraction (FF) in the lumbar spine due to the interaction of gender and age groups.

Methods

44 healthy volunteers (20 males, 30–65 years old and 24 females, 30–69 years old) underwent 3T magnetic resonance spectroscopy (MRS) and conventional MRI examination of the lumbar spine; single-voxel spectrum was acquired for each vertebral body (VB). After controlling body mass index (BMI), a two-way between-groups multivariate analysis of covariance (MANCOVA) assessed the gender and age group differences in FF quantification for each lumbar VB.

Results

There was a significant interaction between gender and age group, p = .017, with a large effect size (partial η² = .330). However the interaction explained only 33% of the observed variance. Main effects were not statistically significant. BMI was non-significantly related to FF quantification.

Conclusions

Young males showed a high FF content, which declined in the 4th decade, then increased the next 3 decades to reach a FF content just below the initial FF means. Females’ FF were low in the 3rd decade, depicted an accelerated increase in the 4th decade, then a gradual increase the next 3 decades to reach a FF content similar to males’ values. Our findings suggest that quantification of bone marrow FF using MRS might be used as a surrogate biomarker of bone marrow activity in clinical settings.     

mDixon Quant脂肪定量技术对强直性脊柱炎骶髂关节炎的应用研究

目的 探讨mDIXON Quant脂肪定量技术在强直性脊柱炎骶髂关节病变中的应用价值。方法 收集诊断明确的强直性脊柱炎患者63名,20名健康志愿者。所有受试者均行双侧骶髂关节常规扫描、mDIXON Quant检查。观察患者的影像表现、BASDAI评分、实验室指标将患者分为3组：早期活动组、慢性活动组、非活动组,在mDIXON Quant序列脂肪分数映射图中测量三组骨髓水肿区、脂肪沉积区以及四组病变外区的脂肪分数,比较早期活动组、慢性活动组骨髓水肿病灶以及慢性活动组、非活动组的脂肪沉积病灶脂肪分数的差异。应用单因素方差分析比较4组间病变外区骨髓的脂肪分数的差异。结果 骨髓水肿灶的脂肪分数：慢性活动组高于早期活动组,脂肪分数分别为（30.0±10.6）％、（20.3±10.2）％,脂肪沉积区的脂肪分数：非活动组高于慢性活动组,脂肪分数分别为（89.4±1.1）％、（81.6±1.7）％,病变外区骨髓的脂肪分数,四组间脂肪分数差异无统计学意义（F=1.37,P＞0.05）。结论 mDIXON Quant技术通过测量脂肪分数,可以量化骶髂关节炎骨髓水肿区、脂肪沉积区的脂肪含量,在判断病情变化中具有价值。     

磁共振波谱技术在腰椎原发性骨质疏松中的诊断价值

目的探讨磁共振(MR)波谱脂肪测量技术评估腰椎原发性骨质疏松的价值。方法利用1.5T MR波谱(MRS)及双能X线吸收法(DXA)对56例研究对象进行检查,收集腰椎L3椎体脂肪比(FF)及L1~4椎体骨密度(BMD)值,以T值-2.5为临界点分为2组,将T值>-2.5定为阴性组和T值≤-2.5定为阳性组,采用Pearson法对FF-MRS与BMD作相关性分析。结果阴性组与阳性组之间的FF及BMD差异均有统计学意义(P<0.01),FF与BMD平均值存在高度负相关关系(r=-0.806,P<0.01)。结论MR波谱因其在评估骨质量方面有较好的优势,可为原发性骨质疏松评估提供一个有效的辅助方法。     

椎体骨髓状况的磁共振波谱评估

目的 探讨椎体氢质子磁共振波谱对椎体骨髓状况的评估价值. 方法 对152例(30～80岁,平均58岁±14岁)女性志愿者进行腰椎MR检查.首先常规扫描矢状位T_2WI、T_1WI和横轴位T_2WI.MR常规扫描结束后采用单体素PRESS序列对L_2～L_4椎体进行波谱采集,相应谱线采用SAGE 7.0软件分析并计算相关椎体MRS定量指标.结果 随年龄增大椎体脂肪含量(FF%)逐步增加;椎体水峰线宽(LW)随年龄增加呈逐渐变窄趋势;椎体脂峰线宽未见明显变化趋势.结论氢质子磁共振波谱可以在常规腰椎磁共振基础上无创性地评估椎体骨髓变化状况.     

Age, gender, and skeletal variation in bone marrow composition: a preliminary study at 3.0 Tesla

PURPOSE: To evaluate the efficacy of MR Spectroscopy (MRS) at 3.0 Tesla for the assessment of normal bone marrow composition and assess the variation in terms of age, gender, and skeletal site. MATERIALS AND METHODS: A total of 16 normal subjects (aged between eight and 57 years) were investigated on a 3.0 Tesla GE Signa system. To investigate axial and peripheral skeleton differences, non-water-suppressed spectra were acquired from single voxels in the calcaneus and lumbar spine. In addition, spectra were acquired at multiple vertebral bodies to assess variation within the lumbar spine. Data was also correlated with bone mineral density (BMD) measured in six subjects using dual-energy X-ray absorptiometry (DXA). RESULTS: Fat content was an order of magnitude greater in the heel compared to the spine. An age-related increase was demonstrated in the spine with values greater in men compared to female subjects. Significant trends in vertebral bodies within the same subjects were also shown, with fat content increasing L5 > L1. Population coefficient of variation (CV) was greater for fat fraction (FF) compared to BMD. CONCLUSION: Significant normal variations of marrow composition have been demonstrated, which provide important data for the future interpretation of patient investigations.     

3.0T MR IDEAL-IQ序列对成年女性腰椎脂肪含量测量及临床价值

目的:采用IDEAL-IQ序列对不同年龄成年女性腰椎椎体脂肪含量进行定量分析,间接反映其骨质强度。方法:选取60例健康女性及15例发生腰椎压缩性骨折的成年女性,对每位受试者行腰椎MRI常规序列及IDEAL-IQ序列扫描,在GE后处理工作台上测量其椎体的脂肪分数。结果:对不同年龄组腰椎椎体平均脂肪分数(fatfraction,FF)值及同一年龄组不同椎体的FF值均采用单因素方差分析,结果均具有统计学差异(P值均小于0.05)。随着受试者年龄的增加,腰椎椎体内骨髓脂肪含量逐渐增加,椎体脂肪分数与年龄呈明显的相关性(r=0.82,P<0.05),不同椎体的脂肪分数变化程度也不一样,脂肪分数越高其骨质强度越低。结论:3.0T磁共振IDEAL-IQ序列不失为测量椎体内脂肪含量的快速、可靠的方法,并可早期发现女性椎体骨质强度的变化。     

急性白血病骨髓浸润的动态增强MRI研究及临床意义

目的：采用动态增强MRI(DCE-MRI)分析急性白血病(AL)患者骨髓浸润微循环血流动力学特点及临床意义。方法 47例AL患者行快速小角度激发梯度同波(FLASH)序列T1WI冠状面髋部DCE-MRI,分别在腰椎及双侧髂骨设置ROI,绘制时间-信号强度曲线(ETCs),计算最大强化率（Emax）、强化斜率(slop...