We have recently proposed an optical method for assessing heart structure that uses polarized light measurement of birefringence as an indicator of tissue anisotropy.The highly aligned nature of healthy cardiac muscle...We have recently proposed an optical method for assessing heart structure that uses polarized light measurement of birefringence as an indicator of tissue anisotropy.The highly aligned nature of healthy cardiac muscle tissue has a detectable effect on the polarization of light,resulting in a measurable phase shift(“retardance”).When this organized tissue structure is perturbed,for example after cardiac infarction(heart attack),scar tissue containing disorganized collagen is formed,causing a decrease in the measured retardance values.However,these are dependent not only on tissue anisotropy,but also on the angle between the tissue’s optical anisotropy direction and the beam interrogating the sample.To remove this experimental ambiguity,we present a method that interrogates the sample at two different incident beam angles,thus yielding enough information to uniquely determine the true magnitude and orientation of the tissue optical anisotropy.We use an infarcted porcine heart model to compare these polarimetryderived anisotropy metrics with those obtained with diffusion tensor magnetic resonance imaging(DT-MRI).The latter yields the anisotropy and the direction of tissue water diffusivity,providing an independent measure of tissue anisotropy.The optical and MR results are thus directly compared in a common ex vivo biological model of interest,yielding reasonable agreement but also highlighting some technique-specific differences.展开更多
目的探讨3.0 T MR扩散张量成像(DTI)、骨膜蛋白(Periostin)及溶血磷脂酸(LPA)联合检测在心肌梗死(MI)后左心室重构(LVR)中的预测价值。方法回顾性纳入100例MI病人并收集其临床及入院当天和出院后12个月的影像资料。通过病人出院后12个...目的探讨3.0 T MR扩散张量成像(DTI)、骨膜蛋白(Periostin)及溶血磷脂酸(LPA)联合检测在心肌梗死(MI)后左心室重构(LVR)中的预测价值。方法回顾性纳入100例MI病人并收集其临床及入院当天和出院后12个月的影像资料。通过病人出院后12个月复查超声心动图所得到的左室质量指数(LVMI)将病人分为LVR组(46例)和非LVR组(54例),其中LVR组男30例,女16例,平均年龄(61.31±9.43)岁;非LVR组男35例,女19例,平均年龄(57.93±10.15)岁。收集接受3.0 T DTI扫描MI病人的影像特征,包括梗死区(CIZ)、边缘区(PIZ)及非梗死区(NIZ)的各向异性分数(FA)和平均扩散系数(MD),采用ELISA法检测病人血清Periostin、LPA水平。采用t检验及卡方检验比较2组临床指标和MRI表现的差异,采用多因素Logistic回归分析各项临床指标对MI后心室重构的危险程度,采用受试者操作特征(ROC)曲线下面积(AUC)评估各临床因素对预后的预测价值。结果与非LVR组相比,LVR组的CIZ区FA值及MD值存在差异(P<0.05),而PIZ区与NIZ区的FA值及MD值差异无统计学意义(P>0.05)。LVR组的Periostin、LPA显著高于非LVR组(P<0.05)。高血压、Periostin高水平、LPA高水平、FA降低及MD升高是影响MI病人左心室重构的独立危险因素(均P<0.05);LPA、Periostin、FA及MD预测LVR的AUC分别是0.801、0.864、0.611、0.664,4种指标联合检测对LVR预测的AUC最大为0.904,敏感度为89.6%,特异度为82.4%。结论Periostin、LPA水平、DTI检查FA值及MD值均与MI后心室重构有关,可用于早期预测MI病人LVR。展开更多
基金Support from the Natural Sciences and Engineering Research Council of Canada,the Canadian Institutes of Health Research and the Canadian Foundation for Innovation,is gratefully acknowledged
文摘We have recently proposed an optical method for assessing heart structure that uses polarized light measurement of birefringence as an indicator of tissue anisotropy.The highly aligned nature of healthy cardiac muscle tissue has a detectable effect on the polarization of light,resulting in a measurable phase shift(“retardance”).When this organized tissue structure is perturbed,for example after cardiac infarction(heart attack),scar tissue containing disorganized collagen is formed,causing a decrease in the measured retardance values.However,these are dependent not only on tissue anisotropy,but also on the angle between the tissue’s optical anisotropy direction and the beam interrogating the sample.To remove this experimental ambiguity,we present a method that interrogates the sample at two different incident beam angles,thus yielding enough information to uniquely determine the true magnitude and orientation of the tissue optical anisotropy.We use an infarcted porcine heart model to compare these polarimetryderived anisotropy metrics with those obtained with diffusion tensor magnetic resonance imaging(DT-MRI).The latter yields the anisotropy and the direction of tissue water diffusivity,providing an independent measure of tissue anisotropy.The optical and MR results are thus directly compared in a common ex vivo biological model of interest,yielding reasonable agreement but also highlighting some technique-specific differences.
文摘目的探讨3.0 T MR扩散张量成像(DTI)、骨膜蛋白(Periostin)及溶血磷脂酸(LPA)联合检测在心肌梗死(MI)后左心室重构(LVR)中的预测价值。方法回顾性纳入100例MI病人并收集其临床及入院当天和出院后12个月的影像资料。通过病人出院后12个月复查超声心动图所得到的左室质量指数(LVMI)将病人分为LVR组(46例)和非LVR组(54例),其中LVR组男30例,女16例,平均年龄(61.31±9.43)岁;非LVR组男35例,女19例,平均年龄(57.93±10.15)岁。收集接受3.0 T DTI扫描MI病人的影像特征,包括梗死区(CIZ)、边缘区(PIZ)及非梗死区(NIZ)的各向异性分数(FA)和平均扩散系数(MD),采用ELISA法检测病人血清Periostin、LPA水平。采用t检验及卡方检验比较2组临床指标和MRI表现的差异,采用多因素Logistic回归分析各项临床指标对MI后心室重构的危险程度,采用受试者操作特征(ROC)曲线下面积(AUC)评估各临床因素对预后的预测价值。结果与非LVR组相比,LVR组的CIZ区FA值及MD值存在差异(P<0.05),而PIZ区与NIZ区的FA值及MD值差异无统计学意义(P>0.05)。LVR组的Periostin、LPA显著高于非LVR组(P<0.05)。高血压、Periostin高水平、LPA高水平、FA降低及MD升高是影响MI病人左心室重构的独立危险因素(均P<0.05);LPA、Periostin、FA及MD预测LVR的AUC分别是0.801、0.864、0.611、0.664,4种指标联合检测对LVR预测的AUC最大为0.904,敏感度为89.6%,特异度为82.4%。结论Periostin、LPA水平、DTI检查FA值及MD值均与MI后心室重构有关,可用于早期预测MI病人LVR。
