Lopez-Prades Sandra, Torrecilla-Vall-Llossera Mónica, Rus Mercedes, Cuatrecasas Miriam, O'Callaghan Joan M
Pathology Department, Hospital Clinic Barcelona, C/Villarroel 170, 08036 Barcelona, Spain.
Faculty of Medicine, University of Barcelona, C/Casanova 143, 08036 Barcelona, Spain.
Sensors (Basel). 2025 Apr 21;25(8):2626. doi: 10.3390/s25082626.
We developed a measurement setup and protocol reliably relating complex permittivity measurements with tissue characterization and specific histological features. We measured 148 fresh human tissue samples across 14 tissue types at 51 frequencies ranging from 200 MHz to 20 GHz, using an open-ended coaxial slim probe. Tissue samples were collected using a punch biopsy, ensuring that the sampled area encompassed the region where complex permittivity measurements were performed. This approach minimized experimental uncertainty related to potential position-dependent variations in permittivity. Once measured, the samples were then formalin-fixed and paraffin-embedded (FFPE) to obtain histological slides for microscopic analysis of tissue features. We observed that complex permittivity values are strongly associated with key histological features, including fat content, necrosis, and fibrosis. Most tissue samples exhibiting these features could be differentiated from nominal values for that tissue type, even accounting for statistical variability and instrumental uncertainties. These findings demonstrate the potential of incorporating fast in situ complex permittivity for fresh tissue characterization in pathology workflows. Furthermore, our work lays the groundwork for enhancing databases where complex permittivity values are measured under histological control, enabling precise correlations between permittivity values, tissue characterization, and histological features.
我们开发了一种测量装置和方案，能可靠地将复介电常数测量与组织特征及特定组织学特征联系起来。我们使用开放式同轴细探头，在200兆赫至20吉赫的51个频率下，对14种组织类型的148个新鲜人体组织样本进行了测量。组织样本通过穿刺活检采集，确保采样区域涵盖进行复介电常数测量的区域。这种方法将与介电常数潜在位置依赖性变化相关的实验不确定性降至最低。测量完成后，样本随后进行福尔马林固定和石蜡包埋（FFPE），以获得用于组织特征显微分析的组织学切片。我们观察到复介电常数与关键组织学特征密切相关，包括脂肪含量、坏死和纤维化。即使考虑到统计变异性和仪器不确定性，大多数表现出这些特征的组织样本也能与该组织类型的标称值区分开来。这些发现证明了在病理学工作流程中纳入快速原位复介电常数以进行新鲜组织表征的潜力。此外，我们的工作为增强在组织学控制下测量复介电常数的数据库奠定了基础，从而实现介电常数、组织特征和组织学特征之间的精确关联。
