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Sensitivity investigation of open-ended coaxial probe in skin cancer detection. Phys Eng Sci Med 2023; 46:609-621. [PMID: 36913123 DOI: 10.1007/s13246-023-01236-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2022] [Accepted: 02/16/2023] [Indexed: 03/14/2023]
Abstract
Open-ended coaxial probe method is one of the most common modalities in measuring dielectric properties (DPs) of biological tissues. Due to the significant differences between the tumors and normal tissues in DPs, the technique can be used to detect skin cancer in the early stage. Although various studies have been reported, systematic assessment is in urgent need to advance it to clinical applications, for its parameters interactions and detecting limitations remained unclear. In this study, we aim to provide a comprehensive examination of this method, including the minimum detectable tumor size by using a three-layer skin model via simulation and demonstrated that open-ended coaxial probe method can be used for detection of early-stage skin cancer. The smallest detecting size are subject to different subtypes: for BCC, inside the skin is 0.5 mm radius × 0.1 mm height; for SCC, inside the skin is 1.4 mm × 1.3 mm in radius and height; the smallest distinguishing size of BCC is 0.6 mm × 0.7 mm in radius and height; for SCC is 1.0 mm × 1.0 mm in radius and height; for MM is 0.7 mm × 0.4 mm in radius and height. The experiment results showed that sensitivity was affected by tumor dimension, probe size, skin height, and cancer subtype. The probe is more sensitive to cylinder tumor radius than height growing on the surface of the skin while the smallest size probe is the most sensitive among the working probes. We provide a detailed systematic evaluation of the parameters employed in the method for further applications.
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Sasaki K, Porter E, Rashed EA, Farrugia L, Schmid G. Measurement and image-based estimation of dielectric properties of biological tissues —past, present, and future—. Phys Med Biol 2022; 67. [DOI: 10.1088/1361-6560/ac7b64] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2022] [Accepted: 06/22/2022] [Indexed: 12/23/2022]
Abstract
Abstract
The dielectric properties of biological tissues are fundamental pararmeters that are essential for electromagnetic modeling of the human body. The primary database of dielectric properties compiled in 1996 on the basis of dielectric measurements at frequencies from 10 Hz to 20 GHz has attracted considerable attention in the research field of human protection from non-ionizing radiation. This review summarizes findings on the dielectric properties of biological tissues at frequencies up to 1 THz since the database was developed. Although the 1996 database covered general (normal) tissues, this review also covers malignant tissues that are of interest in the research field of medical applications. An intercomparison of dielectric properties based on reported data is presented for several tissue types. Dielectric properties derived from image-based estimation techniques developed as a result of recent advances in dielectric measurement are also included. Finally, research essential for future advances in human body modeling is discussed.
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Abboud T, Hahn G, Just A, Paidhungat M, Nazarenus A, Mielke D, Rohde V. An insight into electrical resistivity of white matter and brain tumors. Brain Stimul 2021; 14:1307-1316. [PMID: 34481094 DOI: 10.1016/j.brs.2021.08.023] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2021] [Revised: 08/27/2021] [Accepted: 08/31/2021] [Indexed: 11/19/2022] Open
Abstract
BACKGROUND There is a lack of information regarding electrical properties of white matter and brain tumors. OBJECTIVE To investigate the feasibility of in-vivo measurement of electrical resistivity during brain surgery and establish a better understanding of the resistivity patterns of brain tumors in correlation to the white matter. METHODS A bipolar probe was used to measure electrical resistivity during surgery in a prospective cohort of patients with brain tumors. For impedance measurement, the probe applied a constant current of 0.7 μA with a frequency of 140 Hz. The measurement was performed in the white matter within and outside peritumoral edema as well as in non-enhancing, enhancing and necrotic tumor areas. Resistivity values expressed in ohmmeter (Ω∗m) were compared between different intracranial tissues and brain tumors. RESULTS Ninety-two patients (gliomas WHO II:16, WHO III:10, WHO IV:33, metastasis:33) were included. White matter outside peritumoral edema had higher resistivity values (13.3 ± 1.7 Ω∗m) than within peritumoral edema (8.5 ± 1.6 Ω∗m), and both had higher values than brain tumors including non-enhancing (WHO II:6.4 ± 1.3 Ω∗m, WHO III:6.3 ± 0.9 Ω∗m), enhancing (WHO IV:5 ± 1 Ω∗m, metastasis:5.4 ± 1.3 Ω∗m) and necrotic tumor areas (WHO IV:3.9 ± 1.1 Ω∗m, metastasis:4.3 ± 1.3 Ω∗m), p=<0.001. No difference was found between low-grade and anaplastic gliomas, p = 0.808, while resistivity values in both were higher than the highest values found in glioblastomas, p = 0.003 and p = 0.004, respectively. CONCLUSIONS The technique we applied enabled us to measure electrical resistivity of white matter and brain tumors in-vivo presumably with a significant effect with regard to dielectric polarization. Our results suggest that there are significant differences within different areas and subtypes of brain tumors and that white matter exhibits higher electrical resistivity than brain tumors.
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Affiliation(s)
- Tammam Abboud
- Department of Neurosurgery, University Medical Center Göttingen, Robert-Koch-Straße 40, 37075, Göttingen, Germany.
| | - Günter Hahn
- Department of Anesthesiology, EIT Research Unit, University Medical Center Göttingen, Robert-Koch-Straße 40, 37075, Göttingen, Germany
| | - Anita Just
- Department of Anesthesiology, EIT Research Unit, University Medical Center Göttingen, Robert-Koch-Straße 40, 37075, Göttingen, Germany
| | - Mihika Paidhungat
- Department of Neurosurgery, University Medical Center Göttingen, Robert-Koch-Straße 40, 37075, Göttingen, Germany
| | - Angelina Nazarenus
- Department of Neurosurgery, University Medical Center Göttingen, Robert-Koch-Straße 40, 37075, Göttingen, Germany
| | - Dorothee Mielke
- Department of Neurosurgery, University Medical Center Göttingen, Robert-Koch-Straße 40, 37075, Göttingen, Germany
| | - Veit Rohde
- Department of Neurosurgery, University Medical Center Göttingen, Robert-Koch-Straße 40, 37075, Göttingen, Germany
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Han J, Gao Y, Nan X, Yu X, Liu F, Xin SX. Effect of radiofrequency inhomogeneity on water-content based electrical properties tomography and its correction by flip angle maps. Magn Reson Imaging 2021; 78:25-34. [PMID: 33450296 DOI: 10.1016/j.mri.2020.12.020] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2020] [Revised: 12/24/2020] [Accepted: 12/31/2020] [Indexed: 10/22/2022]
Abstract
Water-content based electrical properties tomography (wEPT) can retrieve electrical properties (EPs) from water-content maps. B1+ field information is not involved in the traditional magnetic resonance electrical properties tomography approach. wEPT can be performed through conventional MR scanning, such as T1-weighted spin-echo imaging, which provides convenient access to multiple clinical applications. However, the inhomogeneous radiofrequency (RF) field induced by RF coils would cause inaccuracy in wEPT reconstructions during MR scanning. We conducted a detailed investigation to evaluate the effect of inhomogeneous RF field on wEPT reconstructions to guarantee that EP mapping is desired for clinical practice. Two important considerations are involved, namely, multiple typical coil configurations and various flip angles (FAs). We proposed a correction scheme with actual FA mapping to calibrate the RF inhomogeneity and finally validated it by using human imaging at 3 T. This study illustrates a detailed evaluation for wEPT under imperfect RF homogeneity and further provides a feasible correction procedure to mitigate it. The profound knowledge of wEPT provided in our work will benefit its performance in clinical applications.
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Affiliation(s)
- Jijun Han
- School of Biomedical Engineering, Southern Medical University, Guangzhou, Guangdong, China
| | - Yunyu Gao
- School of Biomedical Engineering, Southern Medical University, Guangzhou, Guangdong, China
| | - Xiang Nan
- Center for Biomedical Engineering, University of Science and Technology of China, Hefei, Anhui, China
| | - Xuefei Yu
- School of Biomedical Engineering, Southern Medical University, Guangzhou, Guangdong, China
| | - Feng Liu
- School of Information Technology and Electrical Engineering, University of Queensland, Brisbane, QLD, Australia
| | - Sherman Xuegang Xin
- School of Biomedical Engineering, Southern Medical University, Guangzhou, Guangdong, China; School of Medicine, South China University of Technology, Guangzhou, Guangdong, China.
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Huang S, Cai W, Han S, Lin Y, Wang Y, Chen F, Shao G, Liu Y, Yu X, Cai Z, Zou Z, Yao S, Wang Q, Li Z. Differences in the dielectric properties of various benign and malignant thyroid nodules. Med Phys 2020; 48:760-769. [PMID: 33119125 DOI: 10.1002/mp.14562] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2020] [Revised: 08/28/2020] [Accepted: 10/14/2020] [Indexed: 12/26/2022] Open
Abstract
PURPOSE This experiment was conducted to investigate the dielectric properties of different types of thyroid nodules. Our goal was to find a simple and fast method to detect thyroid diseases at different stages from the dielectric properties of thyroid nodules. METHODS We used the open-ended coaxial line method to measure the dielectric permittivities of thyroid tissues from 155 patients at frequencies ranging from 1 to 4000 MHz. Tissues that were investigated included normal thyroid tissue and benign and malignant thyroid nodules (nodular goiter, follicular adenoma, papillary carcinoma, and follicular carcinoma), as determined from pathological reports. Differences in dielectric properties were measured between each nodule and the surrounding 1 cm of tissue. RESULTS The analysis results revealed that the dielectric permittivity and conductivity values were positively correlated with the degree of malignancy of the nodule (normal < benign < malignant; all differences P < 0.05). This was more obvious at frequencies within 20~70 MHz, following the order normal tissue < nodular goiter < follicular adenoma < papillary carcinoma < follicular carcinoma. A significant difference (P < 0.05) in dielectric permittivity and conductivity was found when comparing these nodules with the surrounding 1 cm of tissue. CONCLUSIONS Normal, benign, and malignant nodules were successfully distinguished from one another, and dielectric permittivity was found to be a more sensitive parameter than conductivity. In particular, different disease types can be distinguished at a stimulation frequency of 20~70 MHz, which shows that dielectric properties have application prospects for the detection and diagnosis of cancer. At the same time, the dielectric parameter differences between the surrounding 1 cm of tissue and the diseased nodule can distinguish the tumor and its surrounding tissues in real time during surgery to determine the tumor boundary.
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Affiliation(s)
- Shengyi Huang
- Department of General Surgery, Zhujiang Hospital, Southern Medical University, Guangzhou, 510280, China
| | - Weizhen Cai
- Department of General Surgery, Zhujiang Hospital, Southern Medical University, Guangzhou, 510280, China
| | - Shuai Han
- Department of General Surgery, Zhujiang Hospital, Southern Medical University, Guangzhou, 510280, China
| | - Yu Lin
- Department of Pathology, Zhujiang Hospital, Southern Medical University, Guangzhou, 510280, China
| | - Yu Wang
- Department of Pathology, Zhujiang Hospital, Southern Medical University, Guangzhou, 510280, China
| | - Fei Chen
- Department of Thyroid Surgery, Zhujiang Hospital, Southern Medical University, Guangzhou, 510280, China
| | - Guoli Shao
- Special Medical Service Center, Zhujiang Hospital, Southern Medical University, Guangzhou, 510280, China
| | - Yonghong Liu
- School of Biomedical Engineering, Southern Medical University, Guangzhou, 510515, China
| | - Xuefei Yu
- School of Biomedical Engineering, Southern Medical University, Guangzhou, 510515, China
| | - Zhai Cai
- Department of General Surgery, Zhujiang Hospital, Southern Medical University, Guangzhou, 510280, China
| | - Zenan Zou
- Department of General Surgery, Zhujiang Hospital, Southern Medical University, Guangzhou, 510280, China
| | - Shun Yao
- Department of General Surgery, Zhujiang Hospital, Southern Medical University, Guangzhou, 510280, China
| | - Qiaohui Wang
- Department of General Surgery, Zhujiang Hospital, Southern Medical University, Guangzhou, 510280, China
| | - Zhou Li
- Department of General Surgery, Zhujiang Hospital, Southern Medical University, Guangzhou, 510280, China
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Duan S, Zhu Y, Liu F, Xin SX. Numerical Experiments on the Contrast Capability of Magnetic Resonance Electrical Property Tomography. Magn Reson Med Sci 2020; 19:77-85. [PMID: 31019159 PMCID: PMC7067912 DOI: 10.2463/mrms.mp.2018-0167] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022] Open
Abstract
Purpose: Magnetic resonance electrical property tomography (MR EPT) is a technique for non-invasively obtaining the electric property (EP) distribution of biological tissues, with a promising potential for application in the early detection of tumors. However, the contrast capability (CC) of this technique has not been fully studied. This work aims to theoretically explore the CC for detecting the variation of EP values and the size of the imaging region. Methods: A simulation scheme was specifically designed to evaluate the CC of MR EPT. The simulation study has the advantage that the magnetic field can be accurately obtained. EP maps of the designed phantom embedded with target regions of designated various sizes and EPs were reconstructed using the homogeneous Helmholtz equation based on B1+ with different signal-to-noise ratios (SNRs). The CC was estimated by determining the smallest detectable EP contrast when the target region size was as large as the Laplacian kernel and the smallest detectable target region size when the EP contrast was the same as the difference between healthy and malignant tissues in the brain, based on the reconstructed EP maps. Results: Using noise free B1+, the smallest detectable contrastσ and contrastεr were 1% and 3%, respectively, and the smallest detectable target region size was 1 mesh unit (the base unit size used in the simulation) for conductivity and relative permittivity. The smallest detectable EP contrast and target region size were decreased as the B1+ SNR increased. Conclusion: The CC of MR EPT was related with the SNR of the magnetic field. A small EP contrast and size were necessary for detection at a high-SNR magnetic field. Obtaining a high-SNR magnetic field is important for improving the CC of MR EPT.
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Affiliation(s)
- Song Duan
- Department of Radiation Oncology, Sun Yat-sen Memorial Hospital, Sun Yat-sen University
| | - Yurong Zhu
- Department of Biomedical Engineering, Southern Medical University
| | - Feng Liu
- School of Information Technology and Electrical Engineering, University of Queensland
| | - Sherman Xuegang Xin
- School of Medicine, South China University of Technology, Guangzhou Higher Education Mega Centre
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Yu X, Sun Y, Cai K, Yu H, Zhou D, Lu D, Xin SX. Dielectric Properties of Normal and Metastatic Lymph Nodes Ex Vivo From Lung Cancer Surgeries. Bioelectromagnetics 2020; 41:148-155. [PMID: 31912926 DOI: 10.1002/bem.22246] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2019] [Accepted: 12/26/2019] [Indexed: 12/26/2022]
Abstract
The dielectric properties of normal and tumor human tissues have been widely reported in recent years. However, the dielectric properties of intrathoracic lymph nodes (LNs) have not been reported. In this communication, we measured the dielectric properties (i.e., permittivity and conductivity) of ex vivo intrathoracic LNs obtained from lung cancer surgeries. Results show that the permittivity and conductivity of metastatic LNs are higher than those of normal LNs over the frequency range of 1 MHz-4 GHz. Statistically significant differences are observed at single specific frequencies (64, 128, 298, 433, and 915 MHz and 2.45 GHz). Our study provides the basic data to support future-related research and fills the research gap on the dielectric properties of LNs in the lungs. Bioelectromagnetics. 2020;41:148-155. © 2020 Bioelectromagnetics Society.
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Affiliation(s)
- Xuefei Yu
- School of Biomedical Engineering, Southern Medical University, Guangzhou, China
| | - Ying Sun
- School of Biomedical Engineering, Southern Medical University, Guangzhou, China
| | - Kaican Cai
- Department of Thoracic Surgery, Nanfang Hospital, Southern Medical University, Guangzhou, China
| | - Hongfeng Yu
- School of Biomedical Engineering, Southern Medical University, Guangzhou, China
| | - Difu Zhou
- Department of Medical Equipment, The Second Affiliated Hospital of Guangzhou Medical University, Guangzhou, China
| | - Di Lu
- Department of Thoracic Surgery, Nanfang Hospital, Southern Medical University, Guangzhou, China
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孙 颖, 于 洪, 周 地, 辛 学, 卢 笛, 蔡 开, 余 学. [Analysis of dielectric properties of metastatic and non-metastatic lymph nodes from lung cancer surgeries using an open-ended coaxial probe]. NAN FANG YI KE DA XUE XUE BAO = JOURNAL OF SOUTHERN MEDICAL UNIVERSITY 2019; 39:1364-1369. [PMID: 31852649 PMCID: PMC6926085 DOI: 10.12122/j.issn.1673-4254.2019.11.15] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Subscribe] [Scholar Register] [Received: 01/03/2019] [Indexed: 11/24/2022]
Abstract
OBJECTIVE To investigate the differences in dielectric properties (relative dielectric constant and conductivity) between metastatic and non-metastatic lymph nodes (LNs). METHODS An open-end coaxial probe (1 MHz to 4 GHz) was used to measure the dielectric properties of the LNs obtained from 76 lung cancer patients. According to the results of pathological examination, the LNs were divided into metastatic and non-metastatic LNs, and the metastatic LNs were divided into lung squamous cell carcinomas and adenocarcinoma. The differences in dielectric properties of the LNs were analyzed at 1 MHz to 4 GHz and at 6 single frequencies (64, 128, 298, 433, 915, and 2450 MHz). RESULTS The metastatic LNs showed higher dielectric properties than non-metastatic LNs in the frequency range from 1 MHz to 4 GHz. No significant differences were found in the dielectric properties between metastatic LNs of lung squamous cell carcinoma and adenocarcinoma. At the 6 single frequencies, the metastatic and non-metastatic LNs showed significant differences in their dielectric properties (P < 0.01). CONCLUSIONS The open-ended coaxial probe technology is not capable of identifying the pathological type of the primary lung cancer from which the metastatic LNs are derived, but it can identify the differences in dielectric properties between metastatic and non-metastatic LNs, and thus provide a reliable means for identification of LN metastasis of lung cancer.
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Affiliation(s)
- 颖 孙
- 南方医科大学生物医学工程学院,广东 广州 510515School of Biomedical Engineering, Southern Medical University, Guangzhou 510515, China
| | - 洪峰 于
- 南方医科大学生物医学工程学院,广东 广州 510515School of Biomedical Engineering, Southern Medical University, Guangzhou 510515, China
| | - 地福 周
- 广州医科大学附属第二医院设备科,广东 广州 510000Department of Medical Equipment, Second Affiliated Hospital of Guangzhou Medical University, Guangzhou 510000, China
| | - 学刚 辛
- 华南理工大学医学院,广东 广州 510000School of Medicine, South China University of Technology, Guangzhou 510000, China
| | - 笛 卢
- 南方医科大学南方医院胸外科,广东 广州 510515Department of Thoracic Surgery, Nanfang Hospital, Southern Medical University, Guangzhou 510515, China
| | - 开灿 蔡
- 南方医科大学南方医院胸外科,广东 广州 510515Department of Thoracic Surgery, Nanfang Hospital, Southern Medical University, Guangzhou 510515, China
| | - 学飞 余
- 南方医科大学生物医学工程学院,广东 广州 510515School of Biomedical Engineering, Southern Medical University, Guangzhou 510515, China
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Jovanov E. Vital Sign Monitoring Using Capacitive Sensing. ANNUAL INTERNATIONAL CONFERENCE OF THE IEEE ENGINEERING IN MEDICINE AND BIOLOGY SOCIETY. IEEE ENGINEERING IN MEDICINE AND BIOLOGY SOCIETY. ANNUAL INTERNATIONAL CONFERENCE 2018; 2018:5930-5933. [PMID: 30441686 DOI: 10.1109/embc.2018.8513528] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Unobtrusive vital sign monitoring is essential for most wearable monitoring applications. This paper presents a new method for unobtrusive vital sign monitoring based on the change in capacitance of passive sensors in contact with the user's body. Unlike traditional capacitive coupling that is commonly used for elimination of the DC component of bioamplifiers, we propose monitoring of heart rate using galvanically isolated capacitive sensors. This paper presents the theory of operation and the implementation of a prototype device for heart rate monitoring. A prototype capacitive sensor was implemented using parallel coplanar plates in contact with the tip of the finger. Preliminary testing allowed us to observe changes in capacitance in the range of 0.1-0.3 pF per heartbeat, or 0.3-0.9% of the measured signal. The detected heart rate was validated using a PPG sensor positioned on the same hand. During a single recording session of 772 s, the detected heart rate was within 3 BPM 42% of the time. Proposed method is sensitive to motion artefacts; however, processing of signals collected from multiple contact points may facilitate removal of motion artifacts. Since many microcontrollers directly support high quality monitoring of capacitance on multiple I/O pins, the proposed method provides a promising solution for a low-power, low-cost, multi-contact monitoring.
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周 地, 翟 伟, 孙 颖, 韩 帅, 黄 陆, 辛 学, 厉 周, 余 学. [Differences in dielectric properties between mucosal and serosal surface of malignant colorectal tissues, adjacent tissues at 1 cm and 3 cm and normal colorectal tissues]. NAN FANG YI KE DA XUE XUE BAO = JOURNAL OF SOUTHERN MEDICAL UNIVERSITY 2018; 38:434-442. [PMID: 29735444 PMCID: PMC6765664 DOI: 10.3969/j.issn.1673-4254.2018.04.11] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Subscribe] [Scholar Register] [Received: 12/02/2017] [Indexed: 06/08/2023]
Abstract
OBJECTIVE To investigate the differences in dielectric properties (relative permittivity and conductivity) between the mucosal surface and serosal surface of malignant colorectal tissues, adjacent tissues at 1 cm and 3 cm from the tumor focus and normal colorectal tissues. METHODS The dielectric properties of the mucosal and serosal surface of malignant colorectal tissues, adjacent tissues (1 cm and 3 cm) and normal colorectal tissues from 39 patients with colorectal cancer were measured with an open-ended coaxial probe within the frequency range of 50 MHz-3 GHz, and the corresponding dielectric properties were analyzed respectively; statistical tests of the data were used to analyze the dielectric properties at 6 specific frequency points. RESULTS The dielectric properties were significantly higher in the malignant mucosa surface than in the adjacent tissues and normal colorectal tissues at the 6 specific frequency points (P<0.01). The dielectric properties decreased progressively in adjacent tissues at 1 cm and 3 cm and normal mucosa surface. The mucosal and serosal surface of malignant tissues showed significant differences in dielectric properties at 64 MHz, 128 MHz, 298 MHz, 433 MHz, and 915 MHz (P<0.01) but not at 2450 MHz (P>0.01), but such differences were not observed in normal tissues (P>0.01). CONCLUSION The dielectric properties of the mucosal surface of the mucosal decrease in the order of malignant colorectal tissue, adjacent tissues at 1 cm and 3 cm from the tumor foci and normal colorectal tissues. The dielectric properties are higher in the mucosal surface than in the serosal surface in the malignant tissue, but comparable in normal colorectal tissues.
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Affiliation(s)
- 地福 周
- 南方医科大学生物医学工程学院,广东 广州 510515School of Biomedical Engineering, Southern Medical University, Guangzhou 510515, China
| | - 伟科 翟
- 南方医科大学珠江医院普外科,广东 广州 510280Department of General Surgery, Zhujiang Hospital, Southern Medical University, Guangzhou 510280, China
| | - 颖 孙
- 南方医科大学生物医学工程学院,广东 广州 510515School of Biomedical Engineering, Southern Medical University, Guangzhou 510515, China
| | - 帅 韩
- 南方医科大学珠江医院普外科,广东 广州 510280Department of General Surgery, Zhujiang Hospital, Southern Medical University, Guangzhou 510280, China
| | - 陆茂 黄
- 南方医科大学生物医学工程学院,广东 广州 510515School of Biomedical Engineering, Southern Medical University, Guangzhou 510515, China
| | - 学刚 辛
- 南方医科大学生物医学工程学院,广东 广州 510515School of Biomedical Engineering, Southern Medical University, Guangzhou 510515, China
| | - 周 厉
- 南方医科大学珠江医院普外科,广东 广州 510280Department of General Surgery, Zhujiang Hospital, Southern Medical University, Guangzhou 510280, China
| | - 学飞 余
- 南方医科大学生物医学工程学院,广东 广州 510515School of Biomedical Engineering, Southern Medical University, Guangzhou 510515, China
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张 洒, 厉 周, 辛 学. [Support vector machine?assisted diagnosis of human malignant gastric tissues based on dielectric properties]. NAN FANG YI KE DA XUE XUE BAO = JOURNAL OF SOUTHERN MEDICAL UNIVERSITY 2017; 37:1637-1642. [PMID: 29292258 PMCID: PMC6744023 DOI: 10.3969/j.issn.1673-4254.2017.12.13] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Subscribe] [Scholar Register] [Received: 07/14/2017] [Indexed: 06/07/2023]
Abstract
OBJECTIVE To achieve differential diagnosis of normal and malignant gastric tissues based on discrepancies in their dielectric properties using support vector machine. METHODS The dielectric properties of normal and malignant gastric tissues at the frequency ranging from 42.58 to 500 MHz were measured by coaxial probe method, and the Cole?Cole model was used to fit the measured data. Receiver?operating characteristic (ROC) curve analysis was used to evaluate the discrimination capability with respect to permittivity, conductivity, and Cole?Cole fitting parameters. Support vector machine was used for discriminating normal and malignant gastric tissues, and the discrimination accuracy was calculated using k?fold cross? RESULTS The area under the ROC curve was above 0.8 for permittivity at the 5 frequencies at the lower end of the measured frequency range. The combination of the support vector machine with the permittivity at all these 5 frequencies combined achieved the highest discrimination accuracy of 84.38% with a MATLAB runtime of 3.40 s. CONCLUSION The support vector machine?assisted diagnosis is feasible for human malignant gastric tissues based on the dielectric properties.
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Affiliation(s)
- 洒 张
- 南方医科大学生物医学工程学院,广东 广州 510515School of Biomedical Engineering, Southern Medical University, Guangzhou 510515, China
| | - 周 厉
- 南方医科大学珠江医院普外科,广东 广州 510280Department of General Surgery, Zhujiang Hospital, SouthernMedical University, Guangzhou 510280, China
| | - 学刚 辛
- 南方医科大学生物医学工程学院,广东 广州 510515School of Biomedical Engineering, Southern Medical University, Guangzhou 510515, China
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