Objective To quantitatively compare and determine the best pancreatic tumor contrast to noise ratio (CNR) in different dual-energy derived datasets. Methods In this retrospective, single center study, 16 patients (9 m...Objective To quantitatively compare and determine the best pancreatic tumor contrast to noise ratio (CNR) in different dual-energy derived datasets. Methods In this retrospective, single center study, 16 patients (9 male, 7 female, average age 59.4±13.2 years) with pathologically diagnosed pancreatic cancer were enrolled. All patients received an abdominal scan using a dual source CT scanner 7 to 31 days before biopsy or surgery. After injection of iodine contrast agent, arterial and pancreatic parenchyma phase were scanned consequently, using a dual-energy scan mode (100 kVp/230 mAs and Sn 140 kVp/178 mAs) in the pancreatic parenchyma phase. A series of derived dual-energy datasets were evaluated including non-liner blending (non-linear blending width 0-500 HU; blending center -500 to 500 HU), mono-energetic (40-190 keV), 100 kVp and 140 kVp. On each datasets, mean CT values of the pancreatic parenchyma and tumor, as well as standard deviation CT values of subcutaneous fat and psoas muscle were measured. Regions of interest of cutaneous fat and major psoas muscle of 100 kVp and 140 kVp images were calculated. Best CNR of subcutaneous fat (CNR F ) and CNR of the major psoas muscle (CNR M ) of non-liner blending and mono-energetic datasets were calculated with the optimal mono-energetic keV setting and the optimal blending center/width setting for the best CNR. One Way ANOVA test was used for comparison of best CNR between different dual-energy derived datasets. Results The best CNR F (4.48±1.29) was obtained from the non-liner blending datasets at blending center -16.6±103.9 HU and blending width 12.3±10.6 HU. The best CNR F (3.28±0.97) was obtained from the mono-energetic datasets at 73.3±4.3 keV. CNR F in the 100 kVp and 140 kVp were 3.02±0.91 and 1.56±0.56 respectively. Using fat as the noise background, all of these images series showed significant differences (P<0.01) except best CNR F of mono-energetic image sets vs. CNR F of 100 kVp image (P=0.460). Similar results were found using muscle as the noise background (mono-energetic image vs. 100 kVp image: P=0.246; mono-energetic image vs. non-liner blending image: P=0.044; others: P<0.01). Conclusion Compared with mono-energetic datasets and low kVp datasets, non-linear blending image at automatically chosen blending width/window provides better tumor to the pancreas CNR, which might be beneficial for better detection of pancreatic tumors.展开更多
Grating-based x-ray phase contrast imaging has attracted increasing interest in recent decades as multimodal and laboratory source usable method.Specific efforts have been focused on establishing a new extraction meth...Grating-based x-ray phase contrast imaging has attracted increasing interest in recent decades as multimodal and laboratory source usable method.Specific efforts have been focused on establishing a new extraction method to perform practical applications.In this work,noise properties of multi-combination information of newly established information extraction method,so-called angular signal radiography method,are investigated to provide guidelines for targeted and specific applications.The results show that how multi-combination of images can be used in targeted practical applications to obtain a high-quality image in terms of signal-to-noise ratio.Our conclusions can also hold true for upcoming targeted practical applications such as biomedical imaging,non-destructive imaging,and materials science.展开更多
目的探讨自主研发的16通道高分辨盆腔专用线圈(16C)在3.0 T盆腔MRI中的应用价值。材料和方法前瞻性招募35例行盆腔MRI的患者,分别用16C线圈和32通道的体部线圈(32C)采集相同的轴位和矢状位T2WI序列。比较相同序列图像中第三骶椎、子宫...目的探讨自主研发的16通道高分辨盆腔专用线圈(16C)在3.0 T盆腔MRI中的应用价值。材料和方法前瞻性招募35例行盆腔MRI的患者,分别用16C线圈和32通道的体部线圈(32C)采集相同的轴位和矢状位T2WI序列。比较相同序列图像中第三骶椎、子宫肌层、前列腺外周带、直肠壁和闭孔内肌的信噪比(signal to noise ratio,SNR)及对比噪声比(contrast to noise ratio,CNR)。由两位诊断医师各自对两组图像质量和直肠轴位图像直肠壁分层结构的显示度进行主观评分。结果两组线圈相同序列的T2WI矢状位第三骶椎、子宫肌层、前列腺外周带和轴位闭孔内肌的SNR差异具有统计学意义(P<0.05),矢状位第三骶椎、子宫肌层和轴位直肠壁对肌肉的CNR差异具有统计学意义(P<0.05),16C组高于32C组。两组线圈相同序列的T2WI图像质量主观评价差异具有统计学意义(P<0.05),16C组图像质量更优。在轴位T2WI直肠壁分层结构的显示度评价方面两组图像差异具有统计学意义(P<0.05),16C组更优。结论16C线圈在3.0 T磁共振设备上成像质量更好,更有利于盆腔疾病的诊断。展开更多
目的探究上腹部能谱CT智能匹配技术在提高图像对比噪声比(CNR)、降低对比剂使用量中的应用。方法选取行上腹部CT平扫以及双期增强扫描患者126例,分为实验组和对照组,各63例。实验组应用上腹部能谱CT智能匹配技术,对比剂含碘量为300 mg/...目的探究上腹部能谱CT智能匹配技术在提高图像对比噪声比(CNR)、降低对比剂使用量中的应用。方法选取行上腹部CT平扫以及双期增强扫描患者126例,分为实验组和对照组,各63例。实验组应用上腹部能谱CT智能匹配技术,对比剂含碘量为300 mg/kg,并采用滤波反投影法(FBP)获得A组图像;然后采用自适应统计迭代重组技术(AISR)获得B组图像。对照组采用常规CT平扫模式(120 k Vp),对比剂含碘量为450 mg/kg,采用FBP获得C组图像。比较三组图像在40 ke V、50 ke V、60 ke V动脉期和门静脉期的图像噪声以及肝、胰、门静脉、腹主动脉的CNR,并对三组图像进行评分。结果三组在40 ke V、50 ke V、60 ke V动脉期和门静脉期的图像噪声比较,差异均有统计学意义(F分别=187.72、246.35、51.98、127.50、23.15、48.96,P均<0.05)。两两比较结果显示,在40ke V动脉期和门静脉期,C组图像噪声低于B组和A组(q分别=8.32、9.37,P均<0.05);在50ke V动脉期和门静脉期时,B组和C组图像噪声均明显低于A组(q分别=5.73、6.84,P均<0.05);在60 ke V动脉期和门静脉期时,B组图像噪声均明显低于A组和C组(q分别=3.83、3.63,P均<0.05)。三组在40 ke V、50 ke V、60 ke V动脉期和门静脉期的肝、胰、腹主动脉(门静脉)CNR值比较,差异具有统计学意义(F分别=8.52、33.94、60.59、72.70、69.38、44.06;8.27、33.65、42.68、79.84、45.73、80.93;10.64、33.14、31.12、59.96、62.93、39.12,P均<0.05)。在40 ke V、50 ke V、60 ke V时,B组动脉期肝、胰、腹主动脉CNR值和门静脉期肝、胰、门静脉CNR值均明显高于A组和C组,差异均有统计学意义(q分别=16.73、8.72、12.71、10.82、14.65、15.71、11.67、12.51、8.77、10.52、9.79、13.80;8.79、12.83、10.62、14.62、10.81、8.51、10.66、12.79、13.72、9.81、10.53、12.49;4.49、5.64、6.82、10.53、7.52、5.93、11.61、9.27、6.31、10.65、9.51、10.11,P均<0.05)。三组在40 ke V、50 ke V、60 ke V动脉期和门静脉期的图像评分比较,差异均有统计学意义(F分别=42.58、77.97、18.30、25.04、4.25、5.14,P均<0.05)。两两比较结果显示,在40 ke V、50 ke V、60 ke V动脉期和门静脉期时,B组的图像评分最高,明显高于A组和C组(q分别=6.94、7.81、6.02、7.10;3.77、4.58、3.20、4.13;2.97、2.29、2.58、2.02,P均<0.05)。结论上腹部能谱CT智能匹配技术能够获得与常规CT平扫模式的对比剂用量,联合应用自适应统计迭代重组技术后,不仅能提高图像CNR以及降低对比剂用量,而且能提高图像质量。展开更多
目的探讨联合应用AIR-魔毯线圈磁共振成像(MRI)对胸椎结核扫描图像信噪比(signal to noise ratio,SNR)、对比噪声比(contrast to noise ratio,CNR)和脂肪抑制成像效果的价值。方法选取我院80例经手术病理证实为胸椎结核患者,按1:1随机...目的探讨联合应用AIR-魔毯线圈磁共振成像(MRI)对胸椎结核扫描图像信噪比(signal to noise ratio,SNR)、对比噪声比(contrast to noise ratio,CNR)和脂肪抑制成像效果的价值。方法选取我院80例经手术病理证实为胸椎结核患者,按1:1随机分为两组,应用常规线圈(脊柱相控阵线圈,头颈联合线圈)、常规线圈联合AIR魔毯线圈对两组患者分别进行扫描。扫描序列包括胸椎矢状位T_(2)WI,T_(1)WI,T_(2)FLEX,进一步测量、比较SNR,CNR及脂肪抑制效果,分析MRI多序列诊断胸腰椎结核的准确率、特异度和灵敏度。结果常规线圈联合AIR-魔毯线圈扫描组,胸椎矢状位图像的SNR、CNR及压脂效果优于常规线圈组。结论联合应用AIR-魔毯线圈的图像SNR、CNR得到提高,脂肪抑制效果稳定良好。展开更多
目的探讨智能快速磁共振技术(intelligent quick magnetic resonance,IQMR)在冈上肌肌腱损伤中的应用价值。材料与方法对40例冈上肌肌腱损伤患者行肩关节冠状位快速T2WI脂肪抑制(T2WI fat saturation,T2WI-FS)和常规T2WI-FS序列扫描,将...目的探讨智能快速磁共振技术(intelligent quick magnetic resonance,IQMR)在冈上肌肌腱损伤中的应用价值。材料与方法对40例冈上肌肌腱损伤患者行肩关节冠状位快速T2WI脂肪抑制(T2WI fat saturation,T2WI-FS)和常规T2WI-FS序列扫描,将快速T2WI-FS序列的图像传入IQMR后处理系统,自动生成T2WI-FS_(IQMR)图像。由两位放射科医师各自独立对T2WI-FS_(快速)、T2WI-FS_(常规)和T2WI-FS_(IQMR)序列的三组图像的病灶细节清晰度、解剖结构清晰度、整体图像伪影和整体图像质量进行定性评分;根据Zlatkin分型对三组图像的冈上肌肌腱损伤程度进行分级评估,并测量比较三组图像的冈上肌、肱骨头和三角肌的信噪比(signal to noise ratio,SNR)、冈上肌与肱骨头的对比噪声比(contrast to noise ratio,CNR1)和三角肌与肱骨头的对比噪声比(CNR2)。结果T2WI-FS_(IQMR)序列较T2WI-FS_(常规)序列的扫描时间缩短了41%。定性分析:T2WI-FS_(IQMR)图像在病灶细节清晰度、解剖结构清晰度、整体图像伪影和整体图像质量方面的评分均优于T2WI-FS_(快速)和T2WI-FS_(常规)序列图像(P<0.001);三组图像在诊断冈上肌肌腱损伤程度分级上差异无统计学意义(P>0.05)。定量分析:T2WI-FS_(IQMR)组图像的冈上肌、肱骨头和三角肌的SNR、冈上肌与肱骨头的CNR1和三角肌与肱骨头的CNR2均大于T2WI-FS_(快速)组和T2WI-FS_(常规)组(P<0.001)。结论在冈上肌肌腱损伤MRI扫描中,IQMR技术可以明显缩短扫描时间,提高图像质量,值得临床推广应用。展开更多
文摘Objective To quantitatively compare and determine the best pancreatic tumor contrast to noise ratio (CNR) in different dual-energy derived datasets. Methods In this retrospective, single center study, 16 patients (9 male, 7 female, average age 59.4±13.2 years) with pathologically diagnosed pancreatic cancer were enrolled. All patients received an abdominal scan using a dual source CT scanner 7 to 31 days before biopsy or surgery. After injection of iodine contrast agent, arterial and pancreatic parenchyma phase were scanned consequently, using a dual-energy scan mode (100 kVp/230 mAs and Sn 140 kVp/178 mAs) in the pancreatic parenchyma phase. A series of derived dual-energy datasets were evaluated including non-liner blending (non-linear blending width 0-500 HU; blending center -500 to 500 HU), mono-energetic (40-190 keV), 100 kVp and 140 kVp. On each datasets, mean CT values of the pancreatic parenchyma and tumor, as well as standard deviation CT values of subcutaneous fat and psoas muscle were measured. Regions of interest of cutaneous fat and major psoas muscle of 100 kVp and 140 kVp images were calculated. Best CNR of subcutaneous fat (CNR F ) and CNR of the major psoas muscle (CNR M ) of non-liner blending and mono-energetic datasets were calculated with the optimal mono-energetic keV setting and the optimal blending center/width setting for the best CNR. One Way ANOVA test was used for comparison of best CNR between different dual-energy derived datasets. Results The best CNR F (4.48±1.29) was obtained from the non-liner blending datasets at blending center -16.6±103.9 HU and blending width 12.3±10.6 HU. The best CNR F (3.28±0.97) was obtained from the mono-energetic datasets at 73.3±4.3 keV. CNR F in the 100 kVp and 140 kVp were 3.02±0.91 and 1.56±0.56 respectively. Using fat as the noise background, all of these images series showed significant differences (P<0.01) except best CNR F of mono-energetic image sets vs. CNR F of 100 kVp image (P=0.460). Similar results were found using muscle as the noise background (mono-energetic image vs. 100 kVp image: P=0.246; mono-energetic image vs. non-liner blending image: P=0.044; others: P<0.01). Conclusion Compared with mono-energetic datasets and low kVp datasets, non-linear blending image at automatically chosen blending width/window provides better tumor to the pancreas CNR, which might be beneficial for better detection of pancreatic tumors.
基金Project supported by the National Natural Science Foundation of China(Grant No.11535015)the National Special Foundation of China for Major Science Instrument(Grant No.61227802)+3 种基金the National Natural Science Foundation of China(Grant Nos.61405120,61605119,61571305,and 11674232)the Natural Science Foundation of Shenzhen,China(Grant No.JCYJ20170302142617703)the Natural Science Foundation of Shenzhen University,China(Grant Nos.2017017 and 2018041)sponsored by the Post-doctoral International Exchange Program of China
文摘Grating-based x-ray phase contrast imaging has attracted increasing interest in recent decades as multimodal and laboratory source usable method.Specific efforts have been focused on establishing a new extraction method to perform practical applications.In this work,noise properties of multi-combination information of newly established information extraction method,so-called angular signal radiography method,are investigated to provide guidelines for targeted and specific applications.The results show that how multi-combination of images can be used in targeted practical applications to obtain a high-quality image in terms of signal-to-noise ratio.Our conclusions can also hold true for upcoming targeted practical applications such as biomedical imaging,non-destructive imaging,and materials science.
文摘目的探讨自主研发的16通道高分辨盆腔专用线圈(16C)在3.0 T盆腔MRI中的应用价值。材料和方法前瞻性招募35例行盆腔MRI的患者,分别用16C线圈和32通道的体部线圈(32C)采集相同的轴位和矢状位T2WI序列。比较相同序列图像中第三骶椎、子宫肌层、前列腺外周带、直肠壁和闭孔内肌的信噪比(signal to noise ratio,SNR)及对比噪声比(contrast to noise ratio,CNR)。由两位诊断医师各自对两组图像质量和直肠轴位图像直肠壁分层结构的显示度进行主观评分。结果两组线圈相同序列的T2WI矢状位第三骶椎、子宫肌层、前列腺外周带和轴位闭孔内肌的SNR差异具有统计学意义(P<0.05),矢状位第三骶椎、子宫肌层和轴位直肠壁对肌肉的CNR差异具有统计学意义(P<0.05),16C组高于32C组。两组线圈相同序列的T2WI图像质量主观评价差异具有统计学意义(P<0.05),16C组图像质量更优。在轴位T2WI直肠壁分层结构的显示度评价方面两组图像差异具有统计学意义(P<0.05),16C组更优。结论16C线圈在3.0 T磁共振设备上成像质量更好,更有利于盆腔疾病的诊断。
文摘目的探究上腹部能谱CT智能匹配技术在提高图像对比噪声比(CNR)、降低对比剂使用量中的应用。方法选取行上腹部CT平扫以及双期增强扫描患者126例,分为实验组和对照组,各63例。实验组应用上腹部能谱CT智能匹配技术,对比剂含碘量为300 mg/kg,并采用滤波反投影法(FBP)获得A组图像;然后采用自适应统计迭代重组技术(AISR)获得B组图像。对照组采用常规CT平扫模式(120 k Vp),对比剂含碘量为450 mg/kg,采用FBP获得C组图像。比较三组图像在40 ke V、50 ke V、60 ke V动脉期和门静脉期的图像噪声以及肝、胰、门静脉、腹主动脉的CNR,并对三组图像进行评分。结果三组在40 ke V、50 ke V、60 ke V动脉期和门静脉期的图像噪声比较,差异均有统计学意义(F分别=187.72、246.35、51.98、127.50、23.15、48.96,P均<0.05)。两两比较结果显示,在40ke V动脉期和门静脉期,C组图像噪声低于B组和A组(q分别=8.32、9.37,P均<0.05);在50ke V动脉期和门静脉期时,B组和C组图像噪声均明显低于A组(q分别=5.73、6.84,P均<0.05);在60 ke V动脉期和门静脉期时,B组图像噪声均明显低于A组和C组(q分别=3.83、3.63,P均<0.05)。三组在40 ke V、50 ke V、60 ke V动脉期和门静脉期的肝、胰、腹主动脉(门静脉)CNR值比较,差异具有统计学意义(F分别=8.52、33.94、60.59、72.70、69.38、44.06;8.27、33.65、42.68、79.84、45.73、80.93;10.64、33.14、31.12、59.96、62.93、39.12,P均<0.05)。在40 ke V、50 ke V、60 ke V时,B组动脉期肝、胰、腹主动脉CNR值和门静脉期肝、胰、门静脉CNR值均明显高于A组和C组,差异均有统计学意义(q分别=16.73、8.72、12.71、10.82、14.65、15.71、11.67、12.51、8.77、10.52、9.79、13.80;8.79、12.83、10.62、14.62、10.81、8.51、10.66、12.79、13.72、9.81、10.53、12.49;4.49、5.64、6.82、10.53、7.52、5.93、11.61、9.27、6.31、10.65、9.51、10.11,P均<0.05)。三组在40 ke V、50 ke V、60 ke V动脉期和门静脉期的图像评分比较,差异均有统计学意义(F分别=42.58、77.97、18.30、25.04、4.25、5.14,P均<0.05)。两两比较结果显示,在40 ke V、50 ke V、60 ke V动脉期和门静脉期时,B组的图像评分最高,明显高于A组和C组(q分别=6.94、7.81、6.02、7.10;3.77、4.58、3.20、4.13;2.97、2.29、2.58、2.02,P均<0.05)。结论上腹部能谱CT智能匹配技术能够获得与常规CT平扫模式的对比剂用量,联合应用自适应统计迭代重组技术后,不仅能提高图像CNR以及降低对比剂用量,而且能提高图像质量。
文摘目的探讨联合应用AIR-魔毯线圈磁共振成像(MRI)对胸椎结核扫描图像信噪比(signal to noise ratio,SNR)、对比噪声比(contrast to noise ratio,CNR)和脂肪抑制成像效果的价值。方法选取我院80例经手术病理证实为胸椎结核患者,按1:1随机分为两组,应用常规线圈(脊柱相控阵线圈,头颈联合线圈)、常规线圈联合AIR魔毯线圈对两组患者分别进行扫描。扫描序列包括胸椎矢状位T_(2)WI,T_(1)WI,T_(2)FLEX,进一步测量、比较SNR,CNR及脂肪抑制效果,分析MRI多序列诊断胸腰椎结核的准确率、特异度和灵敏度。结果常规线圈联合AIR-魔毯线圈扫描组,胸椎矢状位图像的SNR、CNR及压脂效果优于常规线圈组。结论联合应用AIR-魔毯线圈的图像SNR、CNR得到提高,脂肪抑制效果稳定良好。
文摘目的探讨智能快速磁共振技术(intelligent quick magnetic resonance,IQMR)在冈上肌肌腱损伤中的应用价值。材料与方法对40例冈上肌肌腱损伤患者行肩关节冠状位快速T2WI脂肪抑制(T2WI fat saturation,T2WI-FS)和常规T2WI-FS序列扫描,将快速T2WI-FS序列的图像传入IQMR后处理系统,自动生成T2WI-FS_(IQMR)图像。由两位放射科医师各自独立对T2WI-FS_(快速)、T2WI-FS_(常规)和T2WI-FS_(IQMR)序列的三组图像的病灶细节清晰度、解剖结构清晰度、整体图像伪影和整体图像质量进行定性评分;根据Zlatkin分型对三组图像的冈上肌肌腱损伤程度进行分级评估,并测量比较三组图像的冈上肌、肱骨头和三角肌的信噪比(signal to noise ratio,SNR)、冈上肌与肱骨头的对比噪声比(contrast to noise ratio,CNR1)和三角肌与肱骨头的对比噪声比(CNR2)。结果T2WI-FS_(IQMR)序列较T2WI-FS_(常规)序列的扫描时间缩短了41%。定性分析:T2WI-FS_(IQMR)图像在病灶细节清晰度、解剖结构清晰度、整体图像伪影和整体图像质量方面的评分均优于T2WI-FS_(快速)和T2WI-FS_(常规)序列图像(P<0.001);三组图像在诊断冈上肌肌腱损伤程度分级上差异无统计学意义(P>0.05)。定量分析:T2WI-FS_(IQMR)组图像的冈上肌、肱骨头和三角肌的SNR、冈上肌与肱骨头的CNR1和三角肌与肱骨头的CNR2均大于T2WI-FS_(快速)组和T2WI-FS_(常规)组(P<0.001)。结论在冈上肌肌腱损伤MRI扫描中,IQMR技术可以明显缩短扫描时间,提高图像质量,值得临床推广应用。
