title: An optimal sliding choke antenna for hepatic microwave ablation.
abstract: Microwave ablation (MWA) is a minimally invasive technique increasingly used for thermal therapy of liver tumors. Effective MWA requires efficient interstitial antennas that destroy tumors and a margin of healthy tissue, in situ, while minimizing damage to the rest of the organ. Previously, we presented a method for optimizing MWA antenna designs by coupling finite element method models of antennas with a real-coded, multiobjective genetic algorithm. We utilized this procedure to optimize the design of a minimally invasive choke antenna that can be used to create near-spherical ablation zones of adjustable size (radius 1-2 cm) by adjusting treatment durations and a sliding structure of the antenna. Computational results were validated with experiments in ex vivo bovine liver. The optimization procedure yielded antennas with reflection coefficients below -30 dB, which were capable of creating spherical ablation zones up to 2 cm in radius using 100 W input power at 2.45 GHz with treatment durations under 2 min.
authors.affiliation: Department of Radiation Oncology, University of California, San Francisco, CA 94143, USA. prakashp@radonc.ucsf.edu
authors.forename: Punit
authors.initials: P
authors.lastname: Prakash
authors.forename: Mark C
authors.initials: MC
authors.lastname: Converse
authors.forename: John G
authors.initials: JG
authors.lastname: Webster
authors.forename: David M
authors.initials: DM
authors.lastname: Mahvi
mesh_terms: D055011:Ablation Techniques / Q000295:instrumentation*; D000465:Algorithms; D000818:Animals; D002417:Cattle; D003198:Computer Simulation; D004867:Equipment Design; D020342:Finite Element Analysis; D008099:Liver / Q000601:surgery*; D008872:Microwaves / Q000627:therapeutic use*; D008954:Models, Biological; D015203:Reproducibility of Results