Department of Radiology, Thomas Jefferson University, Philadelphia, Pennsylvania.
Department of Vascular Ultrasound, Shanghai General Hospital, Shanghai, China.
J Ultrasound Med. 2019 Jul;38(7):1865-1873. doi: 10.1002/jum.14884. Epub 2018 Dec 17.
To investigate 3-dimensional subharmonic aided pressure estimation (SHAPE) for measuring intraplaque pressure and the pressure gradient across the plaque cap as novel biomarkers for potentially predicting plaque vulnerability.
Twenty-seven rabbits received a high-cholesterol diet for 2 weeks before a balloon catheter injury to denude the endothelium of the aorta, followed by 8 to 10 weeks of the high-cholesterol diet to create arteriosclerotic plaques. SHAPE imagings of the resulting plaques were performed 12, 16, and 20 weeks after injury using a LOGIQ 9 scanner with a 4D10L probe (GE Healthcare, Milwaukee, WI) before and during an infusion of Definity (Lantheus Medical Imaging, North Billerica, MA) and Sonazoid (GE Healthcare, Oslo, Norway). The ratios of the maximum subharmonic magnitudes at baseline and during the infusion were correlated with the intraplaque pressure and pressure gradient across the plaque cap obtained from direct measurements.
Ten rabbits died prematurely after the balloon injury procedure or due to toxicity from the high-cholesterol diet, whereas 2 rabbits were excluded for other conditions. Five rabbits were scanned in the 12-, 16-, and 20-week groups, respectively. Even after 20 weeks, the plaques that developed were very small (mean ± SD, 0.9 ± 0.4 × 0.14 ± 0.05 cm). Definity performed better than Sonazoid in this application but still only achieved a moderate correlation with pressure across the plaque cap (Definity, r = -0.40; Sonazoid, r = 0.22) and intraplaque pressure (Definity, r = -0.19; Sonazoid, r = -0.11).
Initial findings from plaque pressure estimation using 3-dimensional SHAPE technique showed only moderate correlations with reference standards, but that may be have been due to weaknesses in the animal model studied.
研究三维亚谐波辅助压力估计（SHAPE）测量斑块内压力和斑块帽内压力梯度，作为预测斑块易损性的潜在新型生物标志物。
27 只兔子在接受高胆固醇饮食 2 周后，接受球囊导管损伤以去除主动脉内皮，然后再接受高胆固醇饮食 8 至 10 周，以形成动脉粥样硬化斑块。在损伤后 12、16 和 20 周，使用 LOGIQ 9 扫描仪和 4D10L 探头（GE Healthcare，密尔沃基，威斯康星州）进行 SHAPE 成像，在 Definity（Lantheus Medical Imaging，北比勒陀利亚，马萨诸塞州）和 Sonazoid（GE Healthcare，奥斯陆，挪威）输注前后进行。在基线和输注期间，最大亚谐波幅度的比值与直接测量获得的斑块内压力和斑块帽内压力梯度相关。
10 只兔子在球囊损伤后程序中过早死亡，或因高胆固醇饮食的毒性而死亡，而 2 只兔子因其他情况被排除。在 12、16 和 20 周组中分别对 5 只兔子进行了扫描。即使在 20 周后，形成的斑块仍然非常小（平均±标准差，0.9±0.4×0.14±0.05cm）。与斑块帽内压力（Definity，r=-0.40；Sonazoid，r=0.22）和斑块内压力（Definity，r=-0.19；Sonazoid，r=-0.11）相比，Definity 在该应用中表现优于 Sonazoid，但仍仅达到中度相关性。
使用三维 SHAPE 技术进行斑块压力估计的初步结果仅与参考标准有中度相关性，但这可能是由于所研究的动物模型的弱点所致。
