Seidel G, Beller K D, Aaslid R, Hummel R P, Thibaut U, Vidal-Langwasser M, Kukat B, Kaps M
Department of Neurology, Medical University at Lübeck, Germany.
J Neuroimaging. 1998 Apr;8(2):83-7. doi: 10.1111/jon19988283.
Ultrasound contrast agents improve the signal-to-noise ratio of reflected ultrasound, enhancing the diagnostic value of transcranial Doppler (TCD). In dog studies, we investigated the time course of TCD signal amplitude after application of a phospholipid-containing ultrasound contrast agent (BY963) filled with different gases. The median time of Doppler amplitude enhancement exceeding 5 dB was determined using isoflurane-, isopentane-, trichlortrifluoroethane-, air-, argon-, and perfluoropentane-filled BY963 (69, 72, 75, 78, 88, and 245 seconds respectively). The decrease of time-intensity curve and the duration of signal enhancement showed significant differences comparing the different gases (p = 0.04 and 0.03, respectively). The time course of in vitro stability of BY963 agitated with the different gases measured by absorbance of light (500 nm) showed a retarded decay for perfluoropentane, a rapid decrease for air, isopentane, trichlortrifluoroethane, and argon, and a very rapid decrease using isoflurane. The time course of the different gases depended on the physiochemical properties (lipophilicity and the solubility in water) of the gas encoated in the phospholipid shell. Perfluoropentane-filled BY963 showed the highest in vitro stability and the longest duration of TCD enhancement compared with the other gases used.
超声造影剂可提高反射超声的信噪比，增强经颅多普勒（TCD）的诊断价值。在犬类研究中，我们研究了应用填充不同气体的含磷脂超声造影剂（BY963）后TCD信号幅度的时间进程。使用填充异氟烷、异戊烷、三氯三氟乙烷、空气、氩气和全氟戊烷的BY963确定多普勒幅度增强超过5 dB的中位时间（分别为69、72、75、78、88和245秒）。比较不同气体时，时间-强度曲线的下降和信号增强的持续时间显示出显著差异（分别为p = 0.04和0.03）。通过光吸收（500 nm）测量的用不同气体搅拌的BY963的体外稳定性时间进程显示，全氟戊烷的衰减延迟，空气、异戊烷、三氯三氟乙烷和氩气快速下降，而异氟烷使用时下降非常迅速。不同气体的时间进程取决于包裹在磷脂壳中的气体的物理化学性质（亲脂性和在水中的溶解度）。与使用的其他气体相比，填充全氟戊烷的BY963显示出最高的体外稳定性和最长的TCD增强持续时间。
