粘性弹性聚烯胺MR弹性成形幻象具有可调节的缩比,独立于剪切刚度
L Tyler Williams1, Zheng Cao1, Ali H Lateef1
1Department of Biomedical Engineering, University of Delaware, Newark, DE, 19716, USA.
Journal of the mechanical behavior of biomedical materials
|March 27, 2024
概括
这项研究使用聚烯胺凝开发了新的磁共振弹性成像 (MRE) 幻影. 这些幻影允许独立调整缓冲比率,这对于精确的MRE评估组织力学至关重要.
科学领域:
- 生物医学工程 生物医学工程
- 材料科学 材料科学 材料科学
- 医疗成像医学成像
背景情况:
- 定量磁共振成像 (MRI) 技术需要生理学模拟的测试样本,称为幻影,以准确开发.
- 磁共振弹性图 (MRE) 估计了组织的机械性质,但需要具有独立调节特性的幻影,特别是阻尼率,这一直是具有挑战性的.
- 聚烯胺 (PAA) 水凝对MRE幽灵有希望,但纯PAA具有较低的阻尼;将线性PAA (LPAA) 链纳入PAA网络可以创建粘弹性水凝.
研究的目的:
- 为了评估线性聚烯胺 (LPAA) /聚烯胺 (PAA) 凝作为生理上准确的MRE幻影.
- 为了确定LPAA/PAA凝是否允许独立调整缓比,而不是剪切刚度.
- 为了验证这些凝的使用,测试MRE估计的缓冲比.
主要方法:
- 幻影被制造的PAA度是恒定的 (15.3%重量%) 和不同的LPAA度 (4.5%至8.0%重量%).
- 磁共振弹性成像 (MRE) 在9.4 T和400 Hz振动下进行,以测量阻尼比和剪切刚度.
- 进行了10 Hz的风湿测量,以独立验证幻影的阻尼比率.
主要成果:
- 在缓冲比率和LPAA含量之间观察到显著的正相关性 (p < 0.001).
- 在所有LPAA度中,剪切刚度保持不变,表明减比的独立可调性.
- MRE和类风湿学给出了与LPAA含量 (0.0073对0.0075) 相比的缓冲比率几乎相同的斜率.
结论:
- 聚烯胺凝带有被困的线性聚烯胺链作为有效的MRE幻影.
- 这些LPAA/PAA凝能够独立调整减压比,这对于MRE精度至关重要.
- 这些发现验证了使用这些凝来开发和测试MRE技术来估计缓比率的有效性.
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