Assembly for heat treatment of biological tissues
The invention concerns an assembly for heat treatment of a region of a biological tissue ( 410 ) comprising energy-generating means ( 100 ) to supply energy to the region; means ( 200 ) for measuring and recording spatial temperature distribution in said region; a control unit ( 300 ) comprising means for point-to-point digital processing of the temperature distribution in the region. The invention is characterised in that the energy-generating means comprise means( 110 ) for spatial and temporal distribution of the power available to them on said region, the control unit ( 300 ) comprising means ( 330, 350 ), based on the temperature distribution, for controlling the amount and distribution of energy supplied by the generating means ( 100 ).
1. A method of heat treating a region of biological tissue comprising:
supplying energy to the region including using a transducer for spatially and temporally distributing the energy applied to the aforesaid region;
measuring and recording the spatial temperature distribution in said region using mapping means selected from an MRI or ultrasonic imaging device,
point-by-point processing of the spatial temperature distribution in the region using a computer control station,
wherein the computer control station controls the amount and distribution of energy supplied by the transducer to a target zone of a controlled region.
2. The method of claim 1 , further comprising moving the transducer by a hydraulic system that is connected to the computer control station.
3. The method of claim 1 , wherein the transducer is operably connected to a sinusoidal signal generator, an amplifier and a convertor.
4. The method of claim 3 , wherein the convertor connects the sinusoidal signal generator to the computer control station.
5. The method of claim 1 , further comprising estimating energy losses in the region of biological tissue on the basis of an estimate of the thermal conductivity and of the spatial temperature distribution in the region and its surroundings using the computer control station.
6. The method of claim 1 , further taking into account the thermal conductivity at each point in the region.
7. The method of claim 6 , further comprising
measuring the temperature at each point of a plurality of points, sampling the region and at regular time intervals and
deducing therefrom an estimate of the change in temperature as a function of thermal conductivity from one point of the spatial sample to another.
8. The method of claim 1 , wherein the transducer is an ultrasonic transducer.
9. The method of claim 1 , comprising calculating the amplitude pw of the power to be supplied at a point {right arrow over (r)} at an instant t+Δt using a relationship of the type:
pw
=
Tp
(
r
→
+
Δ
t
)
-
FT
-
1
(
T
*
(
k
→
,
t
)
ⅇ
-
k
2
D
Δ
t
)
FT
-
1
(
α
1
-
ⅇ
-
k
2
D
Δ
t
Dk
2
S
*
(
k
→
)
)
where Tp({right arrow over (r)},t+Δt) is the reference temperature at that point at the moment t+Δt, FT −1 is an inverse Fourier transform, T*({right arrow over (k)},t) is the Fourier transform of the temperature measured at the moment t, D is the heat diffusion coefficient for the tissue, αis the energy absorption coefficient for the tissue, S*({right arrow over (k)}) the Fourier transform of the spatial distribution of the applied energy S({right arrow over (r)}).
10. The method of claim 1 , wherein the transducer comprises energy sources of the ultrasound, laser, microwave or radiofrequency type.
11. A method for the heat treatment of a region of biological tissue comprising:
supplying energy to the region including using a transducer moved by a hydraulic system;
measuring and recording the spatial temperature distribution by using an MRI apparatus in said region,
numerical processing for the point-by-point processing of the spatial temperature distribution in the region using a computer control station,
wherein generating energy to the region comprises a transducer for spatially and temporally distributing the power applied to the aforesaid region, and the computer control station controls the amount and distribution of the energy supplied by the transducer, sinusoidal signal generator, amplifier, and convertor and further wherein the amplitude pw of the power to be supplied at a point {right arrow over (r)}at an instant t+Δt is calculated using a relationship of the type:
pw
=
Tp
(
r
→
+
Δ
t
)
-
FT
-
1
(
T
*
(
k
→
,
t
)
ⅇ
-
k
2
D
Δ
t
)
FT
-
1
(
α
1
-
ⅇ
-
k
2
D
Δ
t
Dk
2
S
*
(
k
→
)
)
where Tp({right arrow over (r)},t+Δt) is the reference temperature at that point at the moment t+Δt, FT −1 is an inverse Fourier transform, T*({right arrow over (k)}, t) is the Fourier transform of the temperature measured at the moment t, D is the heat diffusion coefficient for the tissue, α is the energy absorption coefficient for the tissue, S*({right arrow over (k)}) is the Fourier transform of the spatial distribution of the applied energy S({right arrow over (r)}).