1
|
Jiang AN, Wang S, Yang W, Zhao K, Bai XM, Zhang ZY, Wu W, Chen MH, Yan K. The Role of a Curved Electrode with Controllable Direction in the Radiofrequency Ablation of Liver Tumors Behind Large Vessels. Cardiovasc Intervent Radiol 2019; 42:893-904. [PMID: 30761411 DOI: 10.1007/s00270-019-02182-0] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/08/2018] [Accepted: 02/05/2019] [Indexed: 01/16/2023]
Abstract
PURPOSE To investigate the role of a novel curved radiofrequency ablation (RFA) electrode with controllable direction in the ablation of tumors behind large hepatic vessels in ex vivo bovine and in vivo canine liver experiments. MATERIALS AND METHODS Approval from the institutional animal care and use committee was obtained. In ex vivo experiments, conventional multi-tines expandable electrodes, conventional monopolar straight electrodes and novel curved electrodes were used in the ablation of the bovine liver (n = 90). The ablated area, parallel axis, vertical axis and shape of different electrodes were compared. Then, 24 beagle dogs (10 months old, female) were used for in vivo experiments. Visual tumor targets deeply located in the portal vein were established, and ultrasound-guided liver ablation was performed with different electrodes. The ablation range, target coverage rate, percentage of normal tissue injury and damage to adjacent vessels were evaluated. The Kruskal-Wallis test and the Chi-squared test were used for statistical analysis. RESULTS For the ex vivo study with a 3-cm electrode, the ablation area of the multi-tines expandable electrode group (7.14 ± 0.16 cm2) was significantly larger than that of the novel curved electrode group (5.01 ± 0.30 cm2, P < 0.001) and the monopolar straight electrode group (5.43 ± 0.15 cm2, P < 0.001). The results obtained with the 4-cm electrode in the three groups were in accordance with those of the 3-cm electrode. In vivo, the normal tissue damage area of the novel curved electrode group was smaller than that of the multi-tines expandable electrode group (1.10 ± 0.18 cm2 vs. 4.00 ± 0.18 cm2, P < 0.001). The target coverage rate of the novel curved electrode group was better than that of the monopolar straight electrode group (100% vs. 80.86 ± 1.68%, P < 0.001). The hematoxylin and eosin (H&E) and TUNEL staining results showed that the ablation necrosis area was adjacent to large vessels, but the vascular wall was not significantly damaged in the novel curved electrode group. CONCLUSION Our preliminary results showed that the novel curved RFA electrode with controllable direction could achieve accurate ablation for tumors behind large hepatic vessels, with a better target coverage rate and less damage to normal tissue, than conventional multi-tines expandable electrodes and monopolar straight electrodes.
Collapse
Affiliation(s)
- An-Na Jiang
- Department of Ultrasound, Key Laboratory of Carcinogenesis and Translational Research (Ministry of Education/Beijing), Peking University Cancer Hospital and Institute, 52 Fucheng Road, Haidian District, Beijing, 100142, China
| | - Song Wang
- Department of Ultrasound, Key Laboratory of Carcinogenesis and Translational Research (Ministry of Education/Beijing), Peking University Cancer Hospital and Institute, 52 Fucheng Road, Haidian District, Beijing, 100142, China
| | - Wei Yang
- Department of Ultrasound, Key Laboratory of Carcinogenesis and Translational Research (Ministry of Education/Beijing), Peking University Cancer Hospital and Institute, 52 Fucheng Road, Haidian District, Beijing, 100142, China.
| | - Kun Zhao
- Department of Ultrasound, Key Laboratory of Carcinogenesis and Translational Research (Ministry of Education/Beijing), Peking University Cancer Hospital and Institute, 52 Fucheng Road, Haidian District, Beijing, 100142, China
| | - Xiu-Mei Bai
- Department of Ultrasound, Key Laboratory of Carcinogenesis and Translational Research (Ministry of Education/Beijing), Peking University Cancer Hospital and Institute, 52 Fucheng Road, Haidian District, Beijing, 100142, China
| | - Zhong-Yi Zhang
- Department of Ultrasound, Key Laboratory of Carcinogenesis and Translational Research (Ministry of Education/Beijing), Peking University Cancer Hospital and Institute, 52 Fucheng Road, Haidian District, Beijing, 100142, China
| | - Wei Wu
- Department of Ultrasound, Key Laboratory of Carcinogenesis and Translational Research (Ministry of Education/Beijing), Peking University Cancer Hospital and Institute, 52 Fucheng Road, Haidian District, Beijing, 100142, China
| | - Min-Hua Chen
- Department of Ultrasound, Key Laboratory of Carcinogenesis and Translational Research (Ministry of Education/Beijing), Peking University Cancer Hospital and Institute, 52 Fucheng Road, Haidian District, Beijing, 100142, China
| | - Kun Yan
- Department of Ultrasound, Key Laboratory of Carcinogenesis and Translational Research (Ministry of Education/Beijing), Peking University Cancer Hospital and Institute, 52 Fucheng Road, Haidian District, Beijing, 100142, China
| |
Collapse
|
2
|
Pezeshki PS, Davidson SR, Akens MK, Murphy K, McCann C, Sherar M, Whyne CM, Yee AJM. Helical coil electrode radiofrequency ablation designed for application in osteolytic vertebral tumors--initial evaluation in a porcine model. Spine J 2015; 15:1832-40. [PMID: 25819585 DOI: 10.1016/j.spinee.2015.03.028] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/23/2014] [Revised: 03/02/2015] [Accepted: 03/17/2015] [Indexed: 02/03/2023]
Abstract
BACKGROUND CONTEXT Radiofrequency ablation (RFA) is emerging as a complementary treatment for vertebral metastases. Traditional RFA induces frictional heating leading to local tissue necrosis but often yields small, incomplete, and inhomogeneous zones of ablation in bone. We have developed a new bone-specific RFA electrode that uses a nontraditional frequency (27.12 MHz) and geometry (helical), exploiting a magnetic field and an electric field to generate larger and more comprehensive treatment zones. PURPOSE The purpose of the study was to evaluate the feasibility and safety of the Bone Coil RFA electrode in the spine. STUDY DESIGN This is a preclinical in vivo study based on basic science. METHODS Under institutional approval, six healthy Yorkshire pigs received a sham and an RF treatment in two adjacent cervical vertebrae. To deploy the Bone Coil RFA device in dense porcine vertebrae, a surgical approach was required; an irrigated coring drill bit created a cylindrical path in the vertebral bodies through which the RFA electrodes were placed. The electronic circuit was completed by four grounding pads. Treatment was delivered for 10 minutes at 20 W (n=1), 25 W (n=1), and 30 W (n=4). To monitor the thermal rise and for safety, fiber-optic probes recorded temperatures in the center of each coil and near the spinal foramen. After the procedure, animals were monitored for 2 weeks. Magnetic resonance imaging (MRI) was completed immediately after treatment and at 14 days. Magnetic resonance image segmentation and histology were used to evaluate the ablation volume. RESULTS Comprehensive treatment of the porcine vertebrae was demonstrated by temperature monitoring, MRI, and histology. Large zones of RF ablation were obtained (RF: 3.72±0.73 cm3 vs. sham: 1.98±0.16 cm3, p<.05), confined within the vertebral body. Internal temperatures were elevated with RF (66.1 °C-102.9 °C), without temperature rise outside of the vertebrae (38.2 °C ± 1.5 °C). Mobility, neurological responses, and behavior were normal, consistent with preprocedural examination. Magnetic resonance imaging best visualized ablation at Day 14. Histology revealed comprehensive homogeneous coagulative necrosis with little peripheral sign of repair. CONCLUSIONS The Bone Coil RFA device created large intravertebral ablation volumes with no neurologic sequelae. Radiofrequency thermal ablation (clearly distinguished from the much smaller effects arising from core drilling) corresponded to the homogeneous necrosis visible on histology.
Collapse
Affiliation(s)
- Padina S Pezeshki
- Institute of Biomaterials & Biomedical Engineering (IBBME), University of Toronto, Rosebrugh Building, RM 407 164 College St, Toronto, ON M5S 3G9, Canada; Sunnybrook Health Sciences Centre 2075 Bayview Ave, Room MG 371B Toronto, ON M4N 3M5, Canada
| | - Sean R Davidson
- Techna Institute, University Health Network, 124-100 College St, Toronto, Ontario M5G 1P5, Canada
| | - Margarete K Akens
- Institute of Biomaterials & Biomedical Engineering (IBBME), University of Toronto, Rosebrugh Building, RM 407 164 College St, Toronto, ON M5S 3G9, Canada; Techna Institute, University Health Network, 124-100 College St, Toronto, Ontario M5G 1P5, Canada
| | - Kieran Murphy
- Institute of Biomaterials & Biomedical Engineering (IBBME), University of Toronto, Rosebrugh Building, RM 407 164 College St, Toronto, ON M5S 3G9, Canada; Techna Institute, University Health Network, 124-100 College St, Toronto, Ontario M5G 1P5, Canada
| | - Claire McCann
- Sunnybrook Health Sciences Centre 2075 Bayview Ave, Room MG 371B Toronto, ON M4N 3M5, Canada
| | - Michael Sherar
- Institute of Biomaterials & Biomedical Engineering (IBBME), University of Toronto, Rosebrugh Building, RM 407 164 College St, Toronto, ON M5S 3G9, Canada; Techna Institute, University Health Network, 124-100 College St, Toronto, Ontario M5G 1P5, Canada
| | - Cari M Whyne
- Institute of Biomaterials & Biomedical Engineering (IBBME), University of Toronto, Rosebrugh Building, RM 407 164 College St, Toronto, ON M5S 3G9, Canada; Sunnybrook Health Sciences Centre 2075 Bayview Ave, Room MG 371B Toronto, ON M4N 3M5, Canada
| | - Albert J M Yee
- Institute of Biomaterials & Biomedical Engineering (IBBME), University of Toronto, Rosebrugh Building, RM 407 164 College St, Toronto, ON M5S 3G9, Canada; Sunnybrook Health Sciences Centre 2075 Bayview Ave, Room MG 371B Toronto, ON M4N 3M5, Canada.
| |
Collapse
|
3
|
Yeung SH, Pradhan R, Feng X, Zheng Y. Focused Magnetic Resonance Coupling Coils for Electromagnetic Therapy Applications. IEEE Trans Biomed Eng 2015; 62:2602-2610. [PMID: 25751862 DOI: 10.1109/tbme.2015.2408432] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Abstract
This paper presents the design and construction of a pair of figure-of-eight coils, coupled by magnetic resonance coupling (MRC), which could generate (150 V/m per Ampere) electric field at the focal points for electromagnetic therapy related applications. The E field generated at the targeted site would be significantly enhanced under the same amount of current flowing through the MRC figure-of-eight coils compared to normal coils, due to the superposition of E field contributed by the coils. Furthermore, the MRC figure-of-eight coil is designed and the results are verified in theory, simulation, and experiments. In the ex vivo tissue measurement, 35% current and 82% ohmic power improvements were observed. Since it can enhance the current and ohmic power, the MRC figure-of-eight coils are promising solutions for electromagnetic therapy applications. The potential applications of the coils include noninvasive radio frequency (RF) stimulation, thermoacoustic imaging, electromagnetic field therapies, and RF ablation, etc.
Collapse
Affiliation(s)
- Sai Ho Yeung
- School of Electrical and Electronic Engineering, Nanyang Technological University, Nanyang Avenue, Singapore
| | - Raunaq Pradhan
- School of Electrical and Electronic Engineering, Nanyang Technological University
| | - Xiaohua Feng
- School of Electrical and Electronic Engineering, Nanyang Technological University
| | - Yuanjin Zheng
- School of Electrical and Electronic Engineering, Nanyang Technological University
| |
Collapse
|
4
|
Costanzo GGD, Francica G, Pacella CM. Laser ablation for small hepatocellular carcinoma: State of the art and future perspectives. World J Hepatol 2014; 6:704-715. [PMID: 25349642 PMCID: PMC4209416 DOI: 10.4254/wjh.v6.i10.704] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/02/2013] [Revised: 06/17/2014] [Accepted: 07/29/2014] [Indexed: 02/06/2023] Open
Abstract
During the last two decades, various local thermal ablative techniques for the treatment of unresectable hepatocellular carcinoma (HCC) have been developed. According to internationally endorsed guidelines, percutaneous thermal ablation is the mainstay of treatment in patients with small HCC who are not candidates for surgical resection or transplantation. Laser ablation (LA) represents one of currently available loco-ablative techniques. In this article, the general principles, technique, image guidance, and patient selection are reported. Primary effectiveness, long-term outcome, and complications are also discussed. A review of published data suggests that LA is equivalent to the more popular and widespread radiofrequency ablation in both local tumor control and long-term outcome in the percutaneous treatment of early HCC. In addition, the LA technique using multiple thin laser fibres allows improved ablative effectiveness in HCCs greater than 3 cm. Reference centres should be equipped with all the available techniques so as to be able to use the best and the most suitable procedure for each type of lesion for each patient.
Collapse
|