title: Evaluation of a dual-arm Archimedean spiral array for microwave hyperthermia.
abstract: OBJECTIVE
  This effort describes a third-party performance evaluation of a novel, commercial, dual-armed Archimedean spiral array hyperthermia applicator. The applicator is analysed for its ability to couple efficiently into muscle equivalent phantom loads, operate over a broad bandwidth to help accommodate variable tissue properties and generate predictable and repeatable SAR contours that are adaptable to clinically probable disease shapes.
  
  
  METHODS
  Characterization of the applicator includes E-field and return-loss measurements in liquid muscle tissue-equivalent phantom, as well as comparison of 'treatment-planning' simulations of several possible array SAR patterns with measured SAR from non-coherently driven spiral array antennae.
  
  
  RESULTS
  The applicator demonstrates a reasonably low return loss over a large bandwidth and the ability to generate a very uniform heating pattern. Ability to adjust SAR contours spatially to fit specific shapes is also demonstrated.
  
  
  CONCLUSIONS
  This device should prove a welcome addition to a currently limited set of superficial heating applicators to provide controllable heating of superficial tissue disease.
authors.affiliation: University of California San Francisco, San Francisco, CA, USA.
authors.forename: J E
authors.initials: JE
authors.lastname: Johnson
authors.forename: D G
authors.initials: DG
authors.lastname: Neuman
authors.forename: P F
authors.initials: PF
authors.lastname: Maccarini
authors.forename: T
authors.initials: T
authors.lastname: Juang
authors.forename: P R
authors.initials: PR
authors.lastname: Stauffer
authors.forename: P
authors.initials: P
authors.lastname: Turner
mesh_terms: D004867:Equipment Design; D006801:Humans; D006979:Hyperthermia, Induced / Q000295:instrumentation* / Q000706:statistics & numerical data; D066298:In Vitro Techniques; D008872:Microwaves / Q000627:therapeutic use*; D009132:Muscles; D019047:Phantoms, Imaging; D013813:Therapy, Computer-Assisted