Division of Women's and Children's Health, University of New South Wales, Randwick, NSW, Australia.
Ultrasound Med Biol. 2012 Aug;38(8):1345-51. doi: 10.1016/j.ultrasmedbio.2012.04.007. Epub 2012 Jun 12.
The aim of this study is to quantify fetoplacental cardiac cycle variation in virtual organ computer-aided analysis (VOCAL) power Doppler (PD) indices by novel application of spatio-temporal imaging correlation (STIC). We recruited 25 healthy women (20-34 weeks gestation) with uncomplicated, viable singleton pregnancies with anterior placentae. Three four-dimensional (4-D) STIC PD datasets of the fetoplacental circulation were obtained above the placental cord insertion. The vascularization index (VI), flow index (FI) and vascularization-flow index (VFI) were calculated offline using a standardized spherical sonobiopsy technique for all frames of the cardiac cycle. Clear maximum (systole) and minimum (diastole) values with progressive fluctuation were seen in the majority of datasets (VI 66/75 [88%]; FI 58/75 [77%]; VFI 68/75 [91%]). Variation from mean was: VI ± 3.33% (0.34%-9.69%); VFI ± 3.46% (0.27%-10.02%); FI ± 0.74% (0.14%-1.60%). All indices were significantly higher in systole than diastole (p < 0.001). Mean systolic:diastolic ratios were: VI 1.07 (SD 0.06), FI 1.01 (SD 0.01) and VFI 1.07 (SD 0.06). Intraclass correlation coefficients (ICCs) for the frames ascribed to systole and diastole and to the mean value across the cardiac cycle of the indices (95% confidence interval [CI]) were: systole VI 0.91 (0.83-0.96), FI 0.85 (0.72-0.92), VFI 0.92 (0.85-0.96); diastole VI 0.91 (0.84-0.96), FI 0.84 (0.71-0.92), VFI 0.92 (0.86-0.96); mean VI 0.91 (0.84-0.96), FI 0.84 (0.72-0.92), VFI 0.92 (0.86-0.96). There is clear cardiac cycle variation in VOCAL indices of fetoplacental blood flow, establishing the need to control for phase of the cardiac cycle, and raising the possibility of future 4-D evaluation of vascular flow change or impedance.
本研究旨在通过时空成像相关（STIC）的新应用，量化虚拟器官计算机辅助分析（VOCAL）能量多普勒（PD）指数中胎-胎盘心脏周期的变化。我们招募了 25 名健康女性（20-34 周妊娠），具有简单、可行的单胎妊娠和前胎盘。在胎盘脐带插入上方获得三个胎儿-胎盘循环的四维（4-D）STIC PD 数据集。使用标准化的球形 sonobiopsy 技术计算所有心脏周期帧的血管化指数（VI）、流量指数（FI）和血管化-流量指数（VFI）。在大多数数据集（VI 66/75 [88%]；FI 58/75 [77%]；VFI 68/75 [91%]）中可见到清晰的最大（收缩期）和最小（舒张期）值，且呈渐进波动。从平均值的变化为：VI ± 3.33%（0.34%-9.69%）；VFI ± 3.46%（0.27%-10.02%）；FI ± 0.74%（0.14%-1.60%）。所有指数在收缩期均显著高于舒张期（p < 0.001）。平均收缩期：舒张期比值为：VI 1.07（SD 0.06），FI 1.01（SD 0.01）和 VFI 1.07（SD 0.06）。分配给收缩期和舒张期以及整个心动周期指数的平均值的帧的组内相关系数（ICC）（95%置信区间[CI]）为：收缩期 VI 0.91（0.83-0.96），FI 0.85（0.72-0.92），VFI 0.92（0.85-0.96）；舒张期 VI 0.91（0.84-0.96），FI 0.84（0.71-0.92），VFI 0.92（0.86-0.96）；平均 VI 0.91（0.84-0.96），FI 0.84（0.72-0.92），VFI 0.92（0.86-0.96）。在胎儿-胎盘血流的 VOCAL 指数中存在明显的心动周期变化，这表明需要控制心动周期的阶段，并提出了未来评估血管流量变化或阻抗的 4-D 可能性。
