皮肤组织介电常数:日间时间和皮肤深度的依赖性
1Department of Medical Education, Dr. Kiran C. Patel College of Allopathic Medicine, Nova Southeastern University, Fort Lauderdale, Florida, USA.
Clinical physiology and functional imaging
|November 17, 2024
概括
用组织介电常数 (TDC) 测量的皮肤水含量,在一天中略有下降,特别是在较浅的深度. 在临床相关的2.5mm深度下,这一日内变化是最小的.
科学领域:
- 皮肤病学 皮肤病学
- 生物物理学的生物物理.
- 医疗器械 医疗器械 医疗器械
背景情况:
- 皮肤的水含量对于了解皮肤生理学和诊断诸如等疾病至关重要.
- 组织介电常数 (TDC) 是衡量皮肤水分的一种常见方法.
- 目前的临床TDC测量通常使用单个深度 (2.5mm),可能会忽视日内变化.
研究的目的:
- 为了研究皮肤组织介电常数 (TDC) 在多个测量深度中的一天内变化.
- 为了确定皮肤水测量的日间时间 (TOD) 和深度依赖.
- 为临床实践提供有关TDC测量时间和深度选择的信息.
主要方法:
- 十二名参与者在两天内每隔2小时自测前臂TDC.
- 在四个深度进行测量:0.5mm,1.5mm,2.5mm和5.0mm.
- 参与者接受了统一测量技术的标准化培训.
主要成果:
- 从早上到晚上观察到TDC略有下降,最明显的是0.5mm (4%的减少).
- 在1.5mm (2.7%的减少) 时,TDC的减少不那么显著.
- 在2.5mm或5.0mm深处没有发现TDC的显著TOD-依赖性下降.
结论:
- 皮肤TDC在一天中呈现较小的下降趋势,在较浅的水深处的影响更大.
- 临床相关性在于了解基于TDC的皮肤水估计的可靠性,考虑到TOD和深度.
- 在临床相关的深度 (≥2.5mm),TOD诱导的皮肤水的变化是微不足道的 (≤4%).
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