Haemmerich Dieter, Staelin S T, Tsai J Z, Tungjitkusolmun S, Mahvi D M, Webster J G
Department of Surgery, University of Wisconsin-Madison, 600 Highland Avenue, WI 53792, USA.
Physiol Meas. 2003 May;24(2):251-60. doi: 10.1088/0967-3334/24/2/302.
Knowledge of electrical tissue conductivity is necessary to determine deposition of electromagnetic energy and can further be used to diagnostically differentiate between normal and neoplastic tissue. We measured 17 rats with a total of 24 tumours of the K12/TRb rat colon cancer cell line. In each animal we measured in vivo hepatic tumour and normal tissue conductivity at seven frequencies from 10 Hz to 1 MHz, at different tumour stages between 6 and 12 weeks after induction. Conductivity of normal liver tissue was 1.26 +/- 0.15 mS cm(-1) at 10 Hz, and 4.61 +/- 0.42 mS cm(-1) at 1 MHz. Conductivity of tumour was 2.69 +/- 0.91 mS cm(-1) at 10 Hz, and 5.23 +/- 0.82 mS cm(-1) at 1 MHz. Conductivity was significantly different between normal and tumour tissue (p < 0.05). We determined the percentage of necrosis and fibrosis at the measurement site. We fitted the conductivity data to the Cole-Cole model. For the tumour data we determined Spearman's correlation coefficients between the Cole-Cole parameters and age, necrosis, fibrosis and tumour volume and found significant correlation between necrosis and the Cole-Cole parameters (p < 0.05). We conclude that necrosis within the tumour and the associated membrane breakdown is likely responsible for the observed change in conductivity.
了解电组织传导性对于确定电磁能量的沉积是必要的，并且可进一步用于在诊断上区分正常组织和肿瘤组织。我们测量了17只患有共24个K12/TRb大鼠结肠癌细胞系肿瘤的大鼠。在每只动物中，我们在诱导后6至12周的不同肿瘤阶段，于10 Hz至1 MHz的七个频率下测量了体内肝肿瘤和正常组织的传导性。正常肝组织在10 Hz时的传导性为1.26±0.15 mS cm(-1)，在1 MHz时为4.61±0.42 mS cm(-1)。肿瘤在10 Hz时的传导性为2.69±0.91 mS cm(-1)，在1 MHz时为5.23±0.82 mS cm(-1)。正常组织和肿瘤组织之间的传导性存在显著差异(p < 0.05)。我们确定了测量部位的坏死和纤维化百分比。我们将传导性数据拟合到Cole-Cole模型。对于肿瘤数据，我们确定了Cole-Cole参数与年龄、坏死、纤维化和肿瘤体积之间的Spearman相关系数，并发现坏死与Cole-Cole参数之间存在显著相关性(p < 0.05)。我们得出结论，肿瘤内的坏死及相关的细胞膜破裂可能是观察到的传导性变化的原因。
