Lasers in Medical Science

, Volume 4, Issue 1, pp 41–53 | Cite as

A mathematical model for interstitial laser treatment of tumours using four fibres

  • Michael Davis
  • John Dowden
  • Adrian Steger
  • Phiroze Kapadia
  • Paul Whiting


A mathematical model is employed to discuss the region treated by local hyperthermia, when the source of heat is a laser whose energy is directed into the treatment region through four optical fibres ending at the corners of a square. If treatment is over a period that is substantially longer than the time for the temperature distribution to reach equilibrium, a steady state model using four point sources can be employed to obtain a general idea of the temperatures reached and the region treated for different power levels and sizes of square. For shorter times, and for more accurate estimation of the regions treated, numerical calculation on a computer is essential. The details of the calculation depend on individual cases, but we demonstrate here that such computations are possible, and present a series of typical results. A comparison is made with the results of a series of experiments on canine liver, showing that it is possible to obtain good qualitative and numerical agreement.

Key words

Mathematical model Laser surgery Optical fibres Tumours Thermal diffusion Multiple fibres 


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Copyright information

© Baillière Tindall 1989

Authors and Affiliations

  • Michael Davis
    • 1
  • John Dowden
    • 2
  • Adrian Steger
    • 3
  • Phiroze Kapadia
    • 1
  • Paul Whiting
    • 1
  1. 1.Department of PhysicsUniversity of EssexColchesterUK
  2. 2.Department of MathematicsUniversity of EssexColchesterUK
  3. 3.The Rayne Institute, Faculty of Clinical SciencesUniversity CollegeLondonUK

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