Probe for heating body tissue

Claim 2

A probe for heating body tissue by high-intensity laser light from a laser light source, said probe comprising: a light guide for coupling to the laser light source and having an exit portion to be introduced into the body tissue; a diffuser element on the light guide made of a base material which is highly transparent to laser light; particles of material highly reflective to laser light embedded in the base material; a tubular sleeve surrounding and spaced from the light guide at a predetermined distance; the tubular sleeve having a cap at an end thereof being made of a material that is transparent to laser light and has good heat conductivity in the area of the diffuser element to transmit heat by conduction and by radiation to the body tissue; the diffuser element being spaced from the cap and surrounded by coolant with coolant between the cap and the diffuser element; the cap allowing isotropic scattering of laser light from the diffuser element; and means including a closed coolant passageway in the tubular sleeve having a channel for flowing coolant through the tubular sleeve toward the body tissue and surrounding the diffuser element to remove a substantial portion of the heat transmitted to the body tissue by heat conduction and from the body tissue, while the laser light source is being operated to produce heat radiation for tumor therapy.

Claim 3

A probe according to claim 1, wherein the particles of highly reflective material are selected from the group consisting of barium sulphate, magnesium oxide and aluminum powder.

Claim 4

A probe according to claim 1 wherein the diffuser element material is selected from the group comprising glass, glass-like plastics, transparent adhesives and methyl acrylates.

Claim 5

A probe according to claim 1 wherein the particles of highly reflective material are homogeneously distributed in the transparent material.

Claim 6

A probe according to claim 1 wherein the particles of highly reflective material are distributed non-homogeneously in said transparent material dependent on a desired radiation characteristic.

Claim 7

A probe according to claim 1 wherein said diffuser element is shaped to produce an approximately spherical heat radiation characteristic.

Claim 8

A probe according to claim 1 wherein said diffuser element is shaped to produce an approximately cylindrical heat radiation characteristic.

Claim 9

A probe according to claim 1 wherein said light guide is hollow and has coolant flowing therein, said light guide and said outer sleeve being spaced to form the passageway for the coolant to flow.

Claim 10

A probe according to claim 1 wherein the tubular sleeve has a free probe end, a membrane divides the passageway in the tubular sleeve into at least two channels extending in parallel to the axis, and wherein said channels communicate in the area of the free probe end.

Claim 11

A probe for heating body tissue by high-intensity laser light from a laser light source, said probe comprising: a light guide for coupling to the laser light source and having an exit portion to be introduced into the body tissue; a diffuser element on the light guide made of a base material which is highly transparent to laser light; particles of material highly reflective to laser light embedded in the base material; a tubular sleeve surrounding and spaced from the light guide at a predetermined distance; the tubular sleeve being made of a material that is transparent to laser light and has good heat conductivity in the area of the diffuser element to transmit heat by conduction and by radiation to the body tissue; and means including a closed coolant passageway in the tubular sleeve having a channel for flowing coolant through the tubular sleeve toward the body tissue to remove a substantial portion of the heat transmitted to the body tissue by heat conduction and from the body tissue while the laser light source is being operated to produce heat radiation for tumor therapy; the tubular sleeve having a free probe end, an inner coaxial sleeve having a radially inner and outer sleeve, the radially inner sleeve surrounding the light guide and forming a first channel portion between said inner sleeve and said light guide and a radially inner one of said sleeves, and a second channel portion being formed between the two sleeves; the two sleeves being transparent and have good heat conductivity at least in the area of the diffuser element, and wherein said two channel portions communicate in the area of the free probe end.

Claim 12

A probe for heating body tissue by high-intensity laser light from a laser light source, said probe comprising: a light guide for coupling to the laser light source and having an exit portion to be introduced into the body tissue; a diffuser element on the light guide made of a base material which is highly transparent to laser light; particles of material highly reflective to laser light embedded in the base material; a tubular sleeve surrounding and spaced from the light guide at a predetermined distance; the tubular sleeve being made of a material that is transparent to laser light and has good heat conductivity in the area of the diffuser element to transmit heat by conduction and by radiation to the body tissue; and means including a closed coolant passageway in the tubular sleeve having a channel for flowing coolant through the tubular sleeve toward the body tissue to remove a substantial portion of the heat transmitted to the body tissue by heat conduction and from the body tissue while the laser light source is being operated to produce heat radiation for tumor therapy; the tubular sleeve having a free probe end, an inner coaxial sleeve having a radially inner and outer sleeve, the radially inner sleeve surrounding the light guide and forming a first channel portion between said inner sleeve and said light guide and a radially inner one of said sleeves, and a second channel portion being formed between the two sleeves; the two sleeves being transparent and have good heat conductivity at least in the area of the diffuser element, and wherein said two channel portions communicate in the area of the free probe end.

Claim 13

A probe according to claim 10 wherein in that the tubular sleeves surrounding the light guide are rigid tubes.

Claim 14

A probe according to claim 1 wherein the outer sleeve surrounding the light guide is flexible.

Claim 15

A probe according to claim 1 wherein the coolant has a sufficient viscosity to flow even at temperatures below 0° C.

Claim 16

A probe according to claim 13 further comprising said coolant which is a mixture of a 0.9% sodium chloride solution and alcohol or methanol.

Claim 17

A probe according to claim 1, wherein the materials forming at least the cap of the probe are nuclear magnetic resonance-compatible.

Claim 18

A probe according to claim 1 wherein a tip on the probe is adapted for puncturing solid tissue at its distal end.

Claim 19

A probe according to claim 1 wherein the cap of the tubular sleeve is made of diamond or quartz glass.

Claim 22

A method in accordance with claim 18 including a cooling system and removing about 80% or more of the laser energy.

Claim 23

A method in accordance with claim 18 including the step of cooling the temperature of the tissue close to the diffuser element down to about 0° C.

Claim 24

A method in accordance with claim 18 including the steps of providing power in the range of 30 watts to 100 watts, and removing about 80% to 90% of the power by the coolant.