System for internal heat treatment of a specific body and its use

A method for calibration of a system for the internal heat treatment of specific bodies by application of microwave energy to an area to be treated, said system comprising:

• a generator for producing microwave energy at a first defined frequency;
• at least two consecutive channels transmitting said microwave energy, each channel generating a microwave treatment signal modulated in amplitude according to a defined, periodic modulation law at a second defined frequency, a carrier wave of the microwave energy of said two consecutive channels exhibiting a phase shift;
• at least one microwave applicator associated with each of said at least two consecutive channels for applying said microwave treatment signal delivered by said channel at separate points in the vicinity of the area to be treated;
• means for calculating and displaying microwave power radiated and instantaneous temperatures of said separate points of the area to be treated;
• a dual-temperature reference radiometer selectively interconnected to each of said at least one microwave applicator for measuring an absolute temperature of a separate point of said separate points associated with said at least one microwave applicator in the vicinity in the area to be treated;
• a three-output calibration module linked to said dual-temperature reference radiometer, a first output of said calibration module being linked to an electrical short-circuit in the microwave frequency band of the radiometer, a second output of said calibration module being linked to a first calibrated resistor of defined value in the frequency band of the radiometer, and a third output of the calibration module being linked to a second calibrated resistor of said defined value;
• a multichannel microwave changeover switch forming a measurement input of said dual-temperature-reference radiometer, said multichannel microwave changeover switch being selectively linked to either one of said at least one microwave applicator or one of said outputs of said calibration module, said dual-temperature-reference radiometer including;
• a first microwave changeover switch comprising two input channels, one connected to an output of said at least one microwave applicator and the other to a microwave short-circuit circuit, and an output being connected to an input channel of said multichannel microwave changeover switch;
• a circulator with three successive channels, a first channel being connected to an output of said multichannel microwave changeover switch, a second channel being connected to an input of a microwave electronic treatment assembly, and a third channel constituting a reference input;
• at least two internal temperature reference sources, and
• second microwave changeover switch with at least two input channels each connected to an output of said at least two reference sources and an output of said second microwave changeover switch being connected to said reference input of said circulator;
• said microwave electronic treatment assembly comprising a synchronization control circuit means for controlling both said first and said second microwave changeover switch, a microwave detector with an input connected through a microwave amplifier to an output of the circulator and a sampling circuit connected to an output of the microwave detector and delivering to said calculating and displaying means corresponding sample values, wherein said method for calibration comprises the steps of:
• a) connecting said measurement input of said dual-temperature-reference radiometer to said first output of said calibration module, resulting in said measurement input of said dual-reference radiometer being short-circuited;
• connecting said second microwave changeover switch of said dual-temperature-reference radiometer to a first temperature reference TR1 and then to a second temperature reference TR2;
• and
• measuring and storing values V01 and V02 of a signal delivered by said sampling circuit when said second microwave changeover switch is connected to said first temperature reference TR1 and said second temperature reference TR2, respectively;
• b) connecting said measurement input of said dual-reference radiometer to said second output of said calibration module, resulting in said measurement input being connected to said first calibrated resistor at a first temperature T1;
• connecting said second microwave changeover switch of said dual-reference radiometer to said first temperature reference TR1 and then to said second temperature reference TR2;
• and
• measuring and storing values V11 and V12 of said signal delivered by said sampling circuit when said second microwave changeover switch is connected to said first temperature reference TR1 and said second temperature reference TR2, respectively;
• c) connecting said measurement input of said dual-reference radiometer to said third output of said calibration module, resulting in said measurement input being connected to said second calibrated resistor at a second temperature T2;
• connecting said second microwave changeover switch of said dual-reference radiometer to said first temperature reference TR1 and then to said second temperature reference TR2;
• and
• measuring and storing corresponding values V21 and V22 of said signal delivered by said sampling circuit when said second microwave changeover switch is connected to said first temperature reference TR1 and said second temperature reference TR2, respectively;
• and
• d) solving the system of linear equations relating to stored values, said values each satisfying a relation of the form:
• Vij=K..DELTA.F (a.K2.times.T.times.(1-.rho.)+Tcab.K2 (1-a).(1-.rho.)-a.sup.2 .rho.+TRj (a.sup.2 +K.sup.2 2..rho.-K.sup.2 1).
• where i.epsilon.]and j.epsilon.
• Vij designates each of said stored values;
• K designates a product of gain G of the chain, with the Boltzmann's constant KB;
• .DELTA.F designates a pass band of said dual-temperature-reference radiometer;
• TRj designates either the first temperature reference TR1 or the second reference temperature TR2 for j=1 and 2 respectively;
• K1 and K2 designate electrical loss coefficients of the first microwave changeover switch of said dual-temperature-reference radiometer for said consecutive channels under consideration;
• a designates electrical losses in a cable linking said measurement input of the dual-reference-temperature radiometer and said inputs of said calibration module;
• Tcab designates a temperature of said cable, with .rho.=0 upon inter-connection of the input of said radiometer to said second or said third input and, thus, to a first or second calibrated resistor, respectively, of the calibration module, and .rho.=1 upon interconnection of the input of said radiometer to said first input and, thus, to said electrical short-circuit of said calibration module.

Method of treating an adenoma of the prostate by application of microwave energy to a given area of the prostate comprising the steps of:

• implanting a rectal applicator and a urethral applicator in the corresponding physiological cavities;
• selectively supplying said rectal applicator with said microwave energy by one of two consecutive channels, wherein said two phase shifted channels comprise a phase-shifted channel and a nonphase shifted channel, p1 supplying said urethral applicator with microwave energy by said phase shifted channel, said given area of the prostate to be treated being situated between said rectal and said urethral applicators, subjecting a carrier wave of the microwave energy transmitted by said two consecutive channels to a relative phase shift;
• emitting a defined microwave energy level to at least one of said applicators;
• and
• modulating said relative phase of the carrier wave of the microwave energy transmitted by said two consecutive channels in order to modulate an energy level transferred to the region of the area to be treated thereby allowing the area to reach a servo controlled temperature for the latter, according to a given slope p or convergence law.