Ionita Ciprian N, Garcia Victor L, Bednarek Daniel R, Snyder Kenneth V, Siddiqui Adnan H, Levy Elad I, Rudin Stephen
Dept. of Biomedical Engineering, State University of New York at Buffalo ; Dept. of Neurosurgery, State University of New York at Buffalo ; Toshiba Stroke and Vascular Research Center, State University of New York at Buffalo.
Toshiba Stroke and Vascular Research Center, State University of New York at Buffalo.
Proc SPIE Int Soc Opt Eng. 2014 Mar 13;9038:90380L. doi: 10.1117/12.2041347.
Parametric imaging maps (PIM's) derived from digital subtraction angiography (DSA) for the cerebral arterial flow assessment in clinical settings have been proposed, but experiments have yet to determine the reliability of such studies. For this study, we have observed the effects of different injection techniques on PIM's. A flow circuit set to physiologic conditions was created using an internal carotid artery phantom. PIM's were derived for two catheter positions, two different contrast bolus injection volumes (5ml and 10 ml), and four injection rates (5, 10, 15 and 20 ml/s). Using a gamma variate fitting approach, we derived PIM's for mean-transit-time (MTT), time-to-peak (TTP) and bolus-arrivaltime (BAT). For the same injection rates, a larger bolus resulted in an increased MTT and TTP, while a faster injection rate resulted in a shorter MTT, TTP, and BAT. In addition, the position of the catheter tip within the vasculature directly affected the PIM. The experiment showed that the PIM is strongly correlated with the injection conditions, and, therefore, they have to be interpreted with caution. PIM images must be taken from the same patient to be able to be meaningfully compared. These comparisons can include pre- and post-treatment images taken immediately before and after an interventional procedure or simultaneous arterial flow comparisons through the left and right cerebral hemispheres. Due to the strong correlation between PIM and injection conditions, this study indicates that this assessment method should be used only to compare flow changes before and after treatment within the same patient using the same injection conditions.
已经有人提出了从数字减影血管造影（DSA）得出的参数成像图（PIM），用于临床环境中的脑动脉血流评估，但实验尚未确定此类研究的可靠性。在本研究中，我们观察了不同注射技术对PIM的影响。使用颈内动脉模型创建了一个设置为生理条件的血流回路。针对两个导管位置、两种不同的对比剂团注注射量（5毫升和10毫升）以及四种注射速率（5、10、15和20毫升/秒）得出了PIM。使用伽马变量拟合方法，我们得出了平均通过时间（MTT）、达峰时间（TTP）和团注到达时间（BAT）的PIM。对于相同的注射速率，较大的团注会导致MTT和TTP增加，而较快的注射速率会导致MTT、TTP和BAT缩短。此外，导管尖端在脉管系统内的位置直接影响PIM。实验表明，PIM与注射条件密切相关，因此，对其进行解释时必须谨慎。PIM图像必须取自同一患者才能进行有意义的比较。这些比较可以包括介入手术前后立即拍摄的治疗前和治疗后图像，或者通过左右脑半球进行的同时动脉血流比较。由于PIM与注射条件之间的强相关性，本研究表明，这种评估方法仅应用于在相同注射条件下比较同一患者治疗前后的血流变化。
