目的探讨压缩感知(CS)技术在无对比剂MR冠状动脉血管成像(NMRCA)中应用的最佳加速因子及其可行性。方法2021年8至11月,前瞻性收集阜阳市人民医院31例疑似冠心病,同时完成冠状动脉CT血管成像和3.0 T NMRCA序列扫描的患者的影像学资料。NM...目的探讨压缩感知(CS)技术在无对比剂MR冠状动脉血管成像(NMRCA)中应用的最佳加速因子及其可行性。方法2021年8至11月,前瞻性收集阜阳市人民医院31例疑似冠心病,同时完成冠状动脉CT血管成像和3.0 T NMRCA序列扫描的患者的影像学资料。NMRCA扫描序列包括常规灵敏度编码(SENSE)序列(加速因子为2)和基于SENSE的CS序列(加速因子分别为4、5、6)。采用Friedman检验和Wilcoxon秩和检验比较4组序列之间的图像质量主观评分及冠状动脉和心肌之间的信号对比度(CMCR)的差异。结果CS序列CS4、CS5和CS6的扫描时间分别为(269±36)、(214±29)、(178±26)s,较常规SENSE2[(343±46)s]分别缩短21.5%、37.5%和48.0%。4组图像的主观评分具有良好的一致性(Kappa=0.769,95%CI为0.738~0.800)。CS4组主观评分及CMCR值与SENSE2组差异无统计学意义(P>0.05),CS5组部分冠状动脉节段及CS6组各冠状动脉节段均与SENSE2组差异具有统计学意义(P<0.05)。结论基于CS技术3.0 T NMRCA具有较好的可行性,CS4可以在保证冠状动脉图像质量下,缩短成像时间,在NMRCA中具有较好的临床应用价值。展开更多
This paper presents an accurate and efficient algorithm for solving the generalized elastic net regularization problem with smoothed l0 penalty for recovering sparse vector. Finding the optimal solution to the unconst...This paper presents an accurate and efficient algorithm for solving the generalized elastic net regularization problem with smoothed l0 penalty for recovering sparse vector. Finding the optimal solution to the unconstrained l0 minimization problem in the recovery of compressive sensed signals is an NP-hard problem. We proposed an iterative algorithm to solve this problem. We then prove that the algorithm is convergent based on algebraic methods. The numerical result shows the efficiency and the accuracy of the algorithm.展开更多
Background:In congenital heart disease(CHD)patients,detailed three-dimensional anatomy depiction plays a pivotal role for diagnosis and therapeutical decision making.Hence,the present study investigated the applicabil...Background:In congenital heart disease(CHD)patients,detailed three-dimensional anatomy depiction plays a pivotal role for diagnosis and therapeutical decision making.Hence,the present study investigated the applicability of an advanced cardiovascular magnetic resonance(CMR)whole heart imaging approach utilizing nonselective excitation and compressed sensing for anatomical assessment and interventional guidance of CHD patients in comparison to conventional dynamic CMR angiography.Methods:86 consecutive pediatric patients and adults with congenital heart disease(age,1 to 74 years;mean,35 years)underwent CMR imaging including a freebreathing,ECG-triggered 3D nonselective SSFP whole heart acquisition using compressed SENSE(nsWHcs).Anatomical assessability and signal intensity ratio(SIR)measurements were compared with conventional dynamic 3D-/4D-MR angiography.Results:The most frequent diagnoses were partial anomalous pulmonary venous drainage(17/86,20%),transposition of the great arteries(15/86,17%),tetralogy of Fallot(12/86,14%),and a single ventricle(7/86,8%).Image quality of nsWHcs was rated as excellent/good in 98%of patients.nsWHcs resulted in a reliable depiction of all large thoracic vessels(anatomic assessability,99%–100%)and the proximal segments of coronary arteries and coronary sinus(>90%).nsWHcs achieved a homogenously distributed SIR in all cardiac cavities and thoracic vessels without a significant difference between pulmonary and systemic circulation(10.9±3.5 and 10.6±3.4;p=0.15),while 3D angiography showed significantly increased SIR for targeted vs.non-targeted circulation(PA-angiography,15.2±8.1 vs.5.8±3.6,p<0.001;PV-angiography,7.0±3.9 vs.17.3±6.8,p<0.001).Conclusions:The proposed nsWHcs imaging approach provided a consistently high image quality and a homogeneous signal intensity distribution within the pulmonary and systemic circulation in pediatric patients and adults with a wide spectrum of congenital heart diseases.nsWHcs enabled detailed anatomical assessment and three-dimensional rec展开更多
文摘目的探讨压缩感知(CS)技术在无对比剂MR冠状动脉血管成像(NMRCA)中应用的最佳加速因子及其可行性。方法2021年8至11月,前瞻性收集阜阳市人民医院31例疑似冠心病,同时完成冠状动脉CT血管成像和3.0 T NMRCA序列扫描的患者的影像学资料。NMRCA扫描序列包括常规灵敏度编码(SENSE)序列(加速因子为2)和基于SENSE的CS序列(加速因子分别为4、5、6)。采用Friedman检验和Wilcoxon秩和检验比较4组序列之间的图像质量主观评分及冠状动脉和心肌之间的信号对比度(CMCR)的差异。结果CS序列CS4、CS5和CS6的扫描时间分别为(269±36)、(214±29)、(178±26)s,较常规SENSE2[(343±46)s]分别缩短21.5%、37.5%和48.0%。4组图像的主观评分具有良好的一致性(Kappa=0.769,95%CI为0.738~0.800)。CS4组主观评分及CMCR值与SENSE2组差异无统计学意义(P>0.05),CS5组部分冠状动脉节段及CS6组各冠状动脉节段均与SENSE2组差异具有统计学意义(P<0.05)。结论基于CS技术3.0 T NMRCA具有较好的可行性,CS4可以在保证冠状动脉图像质量下,缩短成像时间,在NMRCA中具有较好的临床应用价值。
文摘This paper presents an accurate and efficient algorithm for solving the generalized elastic net regularization problem with smoothed l0 penalty for recovering sparse vector. Finding the optimal solution to the unconstrained l0 minimization problem in the recovery of compressive sensed signals is an NP-hard problem. We proposed an iterative algorithm to solve this problem. We then prove that the algorithm is convergent based on algebraic methods. The numerical result shows the efficiency and the accuracy of the algorithm.
文摘Background:In congenital heart disease(CHD)patients,detailed three-dimensional anatomy depiction plays a pivotal role for diagnosis and therapeutical decision making.Hence,the present study investigated the applicability of an advanced cardiovascular magnetic resonance(CMR)whole heart imaging approach utilizing nonselective excitation and compressed sensing for anatomical assessment and interventional guidance of CHD patients in comparison to conventional dynamic CMR angiography.Methods:86 consecutive pediatric patients and adults with congenital heart disease(age,1 to 74 years;mean,35 years)underwent CMR imaging including a freebreathing,ECG-triggered 3D nonselective SSFP whole heart acquisition using compressed SENSE(nsWHcs).Anatomical assessability and signal intensity ratio(SIR)measurements were compared with conventional dynamic 3D-/4D-MR angiography.Results:The most frequent diagnoses were partial anomalous pulmonary venous drainage(17/86,20%),transposition of the great arteries(15/86,17%),tetralogy of Fallot(12/86,14%),and a single ventricle(7/86,8%).Image quality of nsWHcs was rated as excellent/good in 98%of patients.nsWHcs resulted in a reliable depiction of all large thoracic vessels(anatomic assessability,99%–100%)and the proximal segments of coronary arteries and coronary sinus(>90%).nsWHcs achieved a homogenously distributed SIR in all cardiac cavities and thoracic vessels without a significant difference between pulmonary and systemic circulation(10.9±3.5 and 10.6±3.4;p=0.15),while 3D angiography showed significantly increased SIR for targeted vs.non-targeted circulation(PA-angiography,15.2±8.1 vs.5.8±3.6,p<0.001;PV-angiography,7.0±3.9 vs.17.3±6.8,p<0.001).Conclusions:The proposed nsWHcs imaging approach provided a consistently high image quality and a homogeneous signal intensity distribution within the pulmonary and systemic circulation in pediatric patients and adults with a wide spectrum of congenital heart diseases.nsWHcs enabled detailed anatomical assessment and three-dimensional rec
