Laboratory investigationMicrowave Ablation: An Experimental Comparative Study on Internally Cooled Antenna versus Non-internally Cooled Antenna in Liver Models
Section snippets
Microwave Ablation System
The microwave delivery system (FORSEA; Qinghai Microwave Electronic Institute, Nanjing, China) consists of an MTC-3 microwave generator with frequency of 2450 MHz and power output of 5–95 W, a flexible coaxial cable, a water pump, and a 14-gauge microwave antenna (Fig 1).
We used two types of antennas respectively connected with the same microwave generator through flexible coaxial cable. The NIC and IC antennas (Fig 2) both consist of a 10-cm long cable connection, a 16.5-cm long shaft coated
Ex Vivo Porcine Liver Ablation
Table 1 lists the parameters of ablation zones. The ablation zones of IC antenna had shorter LD and greater SD, and the shapes were more spherical (Fig 3). There were significant differences between the two types of antennas in SD (P < .01), LD (P < .01), and SR (P < .01). There was more charring around the NIC antenna than that around the IC antenna in each ablation lesion.
During each ablation with NIC antenna, the maximum temperature of the antenna shafts (ie, the surface temperature) was up
Discussion
In the past, the temperature of antenna shaft in microwave ablation would rise dramatically with the increase of treatment power in a very short duration and resulted in severe tissue and skin burns and unbearable pains. In addition, the shape of the ablation zone was ellipsoidal (the LD was greater than SD), which was not the optimal shape for tumor therapy; the ideal shape for tumor ablation was spherical. Therefore, the treatment duration was limited to a very short period, the output power
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2023, International Journal of Thermal SciencesA review of antenna designs for percutaneous microwave ablation
2021, Physica MedicaCitation Excerpt :However, this particular design exhibits a better impedance matching from 5 to over 8 GHz than the clinical used 2.45 GHz. The addition of a cooling system to the antenna is another effective way to address the backward heating problem [110–112]. A cooling system has been used in various commercially available MW antennas with favorable clinical outcomes [113,114].
Prussian blue nanoparticles: Synthesis, surface modification, and application in cancer treatment
2018, International Journal of PharmaceuticsRadiofrequency vs Microwave Ablation After Neoadjuvant Transarterial Bland and Drug-Eluting Microsphere Chembolization for the Treatment of Hepatocellular Carcinoma
2017, Current Problems in Diagnostic RadiologyCitation Excerpt :MWA appears to resist heat sink, is unaffected by charring, generates larger ablation zones, shorter ablation times, and does not require grounding pads.6,8 Recent advancements in microwave probe technology allow for more predictable ablation zones,9 which can be tailored to lesion morphology.10 Our institution uses drug-eluting microsphere chemoembolization (DEB-TACE) or transarterial embolization (TAE) before most hepatic thermal ablations for HCC to theoretically augment efficacy by decreasing heat sink, improving lesion visualization, and potentially treat understaged microsatellite disease within the treated angiosome.
Comparative study evaluating the efficiency of cooled and uncooled single-treatment MWA in thyroid nodules after a 3-month follow up
2017, European Journal of Radiology OpenCitation Excerpt :A study of Korkusuz et al. describing initial experiences after cMWA also reported an intra-ablative pain score of 2 which is comparable to the results presented in the current study [9]. He et al. compared the temperatures created at the antenna shaft during IC and NIC MWA and found out, that the temperature during IC MWA did not exceed 20 °C while temperatures up to 90 °C were measured at the non internally cooled antennas shaft [19]. This leads to higher patient pain levels and may lead to severe damages as voice changes and nerve palsy as reported by multiple studies and supported by the results of our study [2,5].
Cooled microwave ablation of thyroid nodules: Initial experience
2016, European Journal of RadiologyCitation Excerpt :Unintended tissue necrosis could not be observed in any of the 9 cases above [25]. A reduction of risks for causing local unintended skin burns by using cooled-shaft antenna compared to non-cooled shaft antenna is proved by studies [25]. A study from Liang et al. including a large collective of 1136 patients suffering malignant liver tumor treated with Ultrasound-guided MWA (583 treated with non-cooled shaft antenna, 553 treated with cooled-shaft antenna) underlines the thesis that the use of a cooled-shaft antenna helps minimizing major complications.