Abstract：
OBJECTIVE: We aimed to test whether synthetic T1-weighted imaging derived from a post-contrast Quantitative Transient-state Imaging (QTI) acquisition enabled revealing pathological contrast enhancement in intracranial lesions.
METHODS: The analysis included 141 patients who underwent a 3 Tesla-MRI brain exam with intravenous contrast media administration, with the post-contrast acquisition protocol comprising a three-dimensional fast spoiled gradient echo (FSPGR) sequence and a QTI acquisition. Synthetic T1-weighted images were generated from QTI-derived quantitative maps of relaxation times and proton density. Two neuroradiologists assessed synthetic and conventional post-contrast T1-weighted images for the presence and pattern of pathological contrast enhancement in intracranial lesions. Enhancement volumes were quantitatively compared.
RESULTS: Using conventional imaging as a reference, synthetic T1-weighted imaging was 93% sensitive in revealing the presence of contrast enhancing lesions. The agreement for the presence/absence of contrast enhancement was almost perfect both between readers (k = 1 for both conventional and synthetic imaging) and between sequences (k = 0.98 for both readers). In 91% of lesions, synthetic T1-weighted imaging showed the same pattern of contrast enhancement visible in conventional imaging. Differences in enhancement pattern in the remaining lesions can be due to the lower spatial resolution and the longer acquisition delay from contrast media administration of QTI compared to FSPGR. Overall, enhancement volumes appeared larger in synthetic imaging.
CONCLUSIONS: QTI-derived post-contrast synthetic T1-weighted imaging captures pathological contrast enhancement in most intracranial enhancing lesions. Further comparative studies employing quantitative imaging with higher spatial resolution is needed to support our data and explore possible future applications in clinical trials.
METHODS: The analysis included 141 patients who underwent a 3 Tesla-MRI brain exam with intravenous contrast media administration, with the post-contrast acquisition protocol comprising a three-dimensional fast spoiled gradient echo (FSPGR) sequence and a QTI acquisition. Synthetic T1-weighted images were generated from QTI-derived quantitative maps of relaxation times and proton density. Two neuroradiologists assessed synthetic and conventional post-contrast T1-weighted images for the presence and pattern of pathological contrast enhancement in intracranial lesions. Enhancement volumes were quantitatively compared.
RESULTS: Using conventional imaging as a reference, synthetic T1-weighted imaging was 93% sensitive in revealing the presence of contrast enhancing lesions. The agreement for the presence/absence of contrast enhancement was almost perfect both between readers (k = 1 for both conventional and synthetic imaging) and between sequences (k = 0.98 for both readers). In 91% of lesions, synthetic T1-weighted imaging showed the same pattern of contrast enhancement visible in conventional imaging. Differences in enhancement pattern in the remaining lesions can be due to the lower spatial resolution and the longer acquisition delay from contrast media administration of QTI compared to FSPGR. Overall, enhancement volumes appeared larger in synthetic imaging.
CONCLUSIONS: QTI-derived post-contrast synthetic T1-weighted imaging captures pathological contrast enhancement in most intracranial enhancing lesions. Further comparative studies employing quantitative imaging with higher spatial resolution is needed to support our data and explore possible future applications in clinical trials.
摘要：
目的：我们旨在测试来自对比后定量瞬态成像（QTI）采集的合成T1加权成像是否能够显示颅内病变的病理对比增强。
方法：分析包括141例接受3Tesla-MRI脑部检查并静脉注射造影剂的患者，造影后采集协议包括三维快速破坏梯度回波（FSPGR）序列和QTI采集。从QTI衍生的弛豫时间和质子密度的定量图生成合成的T1加权图像。两名神经放射科医生评估了合成和常规对比后T1加权图像，以了解颅内病变中病理对比增强的存在和模式。定量比较了增强量。
结果：使用常规成像作为参考，合成T1加权成像对显示对比增强病变的敏感性为93%.在阅读器之间（对于常规和合成成像，k=1）和序列之间（对于两个阅读器，k=0.98），对比度增强的存在/不存在的一致性几乎是完美的。在91%的病变中，合成T1加权成像显示与常规成像中可见的对比增强模式相同.与FSPGR相比,剩余病变中的增强模式的差异可能是由于较低的空间分辨率和来自QTI的造影剂施用的较长的采集延迟。总的来说,在合成成像中增强量似乎更大.
结论：QTI衍生的对比后合成T1加权成像在大多数颅内增强病变中捕获病理对比增强。需要采用具有更高空间分辨率的定量成像的进一步比较研究来支持我们的数据并探索在临床试验中可能的未来应用。
方法：分析包括141例接受3Tesla-MRI脑部检查并静脉注射造影剂的患者，造影后采集协议包括三维快速破坏梯度回波（FSPGR）序列和QTI采集。从QTI衍生的弛豫时间和质子密度的定量图生成合成的T1加权图像。两名神经放射科医生评估了合成和常规对比后T1加权图像，以了解颅内病变中病理对比增强的存在和模式。定量比较了增强量。
结果：使用常规成像作为参考，合成T1加权成像对显示对比增强病变的敏感性为93%.在阅读器之间（对于常规和合成成像，k=1）和序列之间（对于两个阅读器，k=0.98），对比度增强的存在/不存在的一致性几乎是完美的。在91%的病变中，合成T1加权成像显示与常规成像中可见的对比增强模式相同.与FSPGR相比,剩余病变中的增强模式的差异可能是由于较低的空间分辨率和来自QTI的造影剂施用的较长的采集延迟。总的来说,在合成成像中增强量似乎更大.
结论：QTI衍生的对比后合成T1加权成像在大多数颅内增强病变中捕获病理对比增强。需要采用具有更高空间分辨率的定量成像的进一步比较研究来支持我们的数据并探索在临床试验中可能的未来应用。
