Brown B H, Highfield P E, Tidy J A
The University of Sheffield, Sheffield, UK.
Technical consultant, Manchester, UK.
J Electr Bioimpedance. 2020 Nov 6;11(1):81-86. doi: 10.2478/joeb-2020-0012. eCollection 2020 Jan.
Colposcopy can be used with Electrical Impedance Spectroscopy (EIS) as an adjunct, to assess the presence of High Grade Cervical Intra-epithelial Neoplasia (CIN2+). This analysis of longitudinal data has used the results from women with a negative colposcopy, in order to see if the initial (index) EIS results were able to predict the women who subsequently developed CIN2+. A further objective was to investigate what tissue structural changes might be reflected in the electrical impedance spectra.
847 patients were referred with low grade cytologly. EIS measurements were made around the transformation zone of the cervix during colposcopy. Every EIS spectrum was matched to a template representing CIN2+ and the result was positive if the match exceeded a probability index threshold. The colposcopic impression was also recorded. All the women who developed biopsy proven CIN2+ within three years of the index colposcopy were identified.
The median follow-up was 30.5 months. Where both CI and EIS were initially positive, there was an increased prevalence (8.13%) of CIN2+ developing as opposed to 3.45% in the remaining patients (p=0.0159). In addition, if three or more EIS spectra were positive there was a higher prevalence (9.62% as opposed to 3.56% p=0.0132) of CIN2+ at three years. The index spectra recorded from the women who developed CIN2+ showed EIS changes consistent with increases in the extracellular volume and in cell size inhomogeneity.
EIS does offer prognostic information on the risk of CIN2+ developing over the three-year period following the EIS measurements. The changes in EIS spectra are consistent with an increase in cell size diversity as pre-malignancy develops. These changes may be a consequence of increased genetic diversity as neoplasia develops.
阴道镜检查可与电阻抗光谱法（EIS）联合使用，以评估高级别宫颈上皮内瘤变（CIN2+）的存在情况。这项纵向数据分析利用了阴道镜检查结果为阴性的女性的数据，旨在观察初始（索引）EIS结果能否预测随后发展为CIN2+的女性。另一个目的是研究电阻抗光谱中可能反映出哪些组织结构变化。
847例患者因低级别细胞学检查结果而被转诊。在阴道镜检查期间，对宫颈转化区进行EIS测量。每个EIS光谱都与代表CIN2+的模板进行匹配，如果匹配超过概率指数阈值，则结果为阳性。同时记录阴道镜检查印象。确定了所有在索引阴道镜检查后三年内活检证实为CIN2+的女性。
中位随访时间为30.5个月。当阴道镜检查印象和EIS最初均为阳性时，CIN2+的发生率增加（8.13%），而其余患者为3.45%（p=0.0159）。此外，如果三个或更多EIS光谱为阳性，则三年时CIN2+的发生率更高（9.62%，而p=0.0132时为3.56%）。发展为CIN2+的女性记录的索引光谱显示，EIS变化与细胞外体积增加和细胞大小不均匀性增加一致。
EIS确实提供了关于EIS测量后三年内发展为CIN2+风险的预后信息。EIS光谱的变化与癌前病变发展过程中细胞大小多样性增加一致。这些变化可能是肿瘤发生过程中基因多样性增加的结果。
