Implantable apparatus for localized heating of tissue

Patent · Thu Jan 01 00:00:00 EST 1987

OSTI ID:866306

Doss, James D ^[1]

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1. Los Alamos, NM

With the object of repetitively treating deep-seated, inoperable tumors by hyperthermia as well as locally heating other internal tissue masses repetitively, a receiving antenna, transmission line, and electrode arrangment are implanted completely within the patient's body, with the receiving antenna just under the surface of the skin and with the electrode arrangement being located so as to most effectively heat the tissue to be treated. An external, transmitting antenna, driven by an external radio-frequency energy source, is closely coupled to the implanted receiving antenna so that the energy coupled across the air-skin interface provides electromagnetic energy suitable for heating the tissue in the vicinity of the implanted electrodes. The resulting increase in tissue temperature may be estimated by an indirect measurement of the decrease in tissue resistivity in the heated region. This change in resistivity appears as a change in the loading of the receiving antenna which can be measured by either determining the change in the phase relationship between the voltage and the current appearing on the transmitting antenna or by measuring the change in the magnitude of the impedance thereof. Optionally, multiple electrode arrays may be activated or inactivated by the application of magnetic fields to operate implanted magnetic reed switches.

• Research Organization: Los Alamos National Laboratory (LANL), Los Alamos, NM (United States)
• DOE Contract Number: W-7405-ENG-36
• Assignee: United States of America as represented by United States (Washington, DC)
• Patent Number(s): US 4679561
• OSTI ID: 866306
• Country of Publication: United States
• Language: English

Related Subjects

implantable
apparatus
localized
heating
tissue
repetitively
treating
deep-seated
inoperable
tumors
hyperthermia
locally
internal
masses
receiving
antenna
transmission
line
electrode
arrangment
implanted
completely
patient
surface
arrangement
located
effectively
heat
treated
external
transmitting
driven
radio-frequency
energy
source
closely
coupled
air-skin
interface
provides
electromagnetic
suitable
vicinity
electrodes
resulting
increase
temperature
estimated
indirect
measurement
decrease
resistivity
heated
region
change
appears
loading
measured
determining
phase
relationship
voltage
current
appearing
measuring
magnitude
impedance
optionally
multiple
arrays
activated
inactivated
application
magnetic
fields
operate
reed
switches
direct measurement
localized heating
electrode array
transmitting antenna
transmission line
magnetic field
magnetic fields
energy source
electromagnetic energy
receiving antenna
multiple electrode
closely coupled
magnetic energy
reed switch
frequency energy
radio-frequency energy
phase relationship
direct measure
energy coupled
magnetic reed
tissue mass
interface provides
internal tissue
table apparatus
locally heating
/607/