Dermal abrasion

A method of dermal abrasion, which includes:

• exposing a source of sterile liquid to a flow of pressurized gas, thereby to cause a pumped supply thereof into a fluid delivery head;
• supplying the pressurized gas to the fluid delivery head;
• combining the gas and liquid supplied to the fluid delivery head, wherein the fluid delivery head has a fluid outlet with a predetermined internal diameter, so as to provide a gas-liquid outflow in the form of a sterile liquid mist jet suspended in a high velocity gas stream;
• and
• exposing to the mist jet, at a preselected distance from the fluid outlet, a portion of skin surface sought to be abraded, thereby separating therefrom at least a portion of the epidermis and removing therefrom the resulting tissue debris.

Apparatus for dermal abrasion, which includes:

• a container for a sterile liquid;
• a fluid delivery head having a liquid entry port and a gas entry port, fluid outlet apparatus, and valve apparatus located between said entry ports and said fluid outlet apparatus and for selectably permitting respective liquid and gas flows from said entry ports to said fluid outlet apparatus;
• liquid conduit apparatus extending between a liquid inlet located within said container and a liquid outlet connected to said liquid entry port of said delivery head;
• gas conduit apparatus extending between a gas inlet and a gas outlet, wherein said gas inlet is connected to a source of pressurized gas and said gas outlet is connected to said gas entry port of said delivery head, and wherein said gas conduit apparatus is connected to said container via an intermediate outlet port;
• and
• apparatus for selectably exposing said source of sterile liquid to a flow of pressurized gas flowing from said gas inlet to said gas outlet and into said gas entry port of said fluid delivery head, thereby to pump said sterile liquid along said liquid conduit apparatus, from said inlet to said outlet, and into said liquid entry port of said fluid delivery head,
• wherein said fluid outlet apparatus includes at least one gas-liquid combining member arranged to receive said gas and liquid flows and to combine them into a gas-liquid outflow which is operative to exit said fluid outlet apparatus in the form of at least one sterile liquid mist jet suspended in a high velocity gas stream, and wherein each jet is operative, when brought to within a preselected distance from the skin surface to be abraded, to separate therefrom at least a portion of the epidermis,
• and wherein said fluid outlet apparatus defines a fluid outlet port having a predetermined diameter and wherein said preselected distance is not greater than 50 times said predetermined diameter
• wherein said gas flow exits said valve apparatus into said gas-liquid combining member at a pressure of a first magnitude and said combining member is operative to cause a pressure drop in the gas flow therethrough such that the pressure of the gas-liquid outflow downstream of said fluid outlet is of a second magnitude, wherein said first magnitude is at least twice said second magnitude so as to cause a shock wave in the gas-liquid flow downstream of said fluid outlet apparatus and atomizing of the liquid portion of said outflow into microscopic droplets thereby to form a liquid mist suspended in the gas portion of said outflow,
• and wherein said fluid outlet apparatus further includes at least one interior nozzle member arranged to provide an outflow of sterile liquid and each said interior nozzle member includes:
• a rear portion configured to fit over said interior nozzle member and arranged to fit over said interior nozzle member so as to define a passageway therebetween for gas flow;
• a waist portion defined by a forward tapering of said rear portion;
• a front portion defining an opening and tapering rearwardly towards said waist portion,
• wherein said passage way is formed so as to be increasingly constricted towards said front portion of said nozzle member, such that said gas flow passing through said passageway is accelerated to at least sonic velocity,
• and wherein said front portion widens toward said opening thereof such that said accelerated gas flow expands and thus undergoes a drop in pressure to a pressure which is sub-atmospheric, such that when said nozzle opening is brought to within a pre-selected distance from the skin surface to be abraded, at least a portion of the epidermis is separated from the skin surface.

Apparatus for dermal abrasion, which includes:

• a container for a sterile liquid;
• a fluid delivery head having a liquid entry port and a gas entry port, fluid outlet apparatus, and valve apparatus located between said entry ports and said fluid outlet apparatus and for selectably permitting respective liquid and gas flows from said entry ports to said fluid outlet apparatus;
• liquid conduit apparatus extending between a liquid inlet located within said container and a liquid outlet connected to said liquid entry port of said delivery head;
• gas conduit apparatus extending between a gas inlet and a gas outlet, wherein said gas inlet is connected to a source of pressurized gas and said gas outlet is connected to said gas entry port of said delivery head, and wherein said gas conduit apparatus is connected to said container via an intermediate outlet port;
• and
• apparatus for selectably exposing said source of sterile liquid to a flow of pressurized gas flowing from said gas inlet to said gas outlet and into said gas entry port of said fluid delivery head, thereby to pump said sterile liquid along said liquid conduit apparatus, from said inlet to said outlet, and into said liquid entry port of said fluid delivery head,
• wherein said fluid outlet apparatus includes at least one gas-liquid combining member arranged to receive said gas and liquid flows and to combine them into a gas-liquid outflow which is operative to exit said fluid outlet apparatus in the form of at least one sterile liquid mist jet suspended in a high velocity gas stream, and wherein each jet is operative, when brought to within a preselected distance from the skin surface to be abraded, to separate therefrom at least a portion of the epidermis,
• wherein said gas flow exits said valve apparatus into said gas-liquid combining member at a pressure of a first magnitude and said combining member is operative to cause a pressure drop in the gas flow therethrough such that the pressure of the gas-liquid outflow downstream of said fluid outlet is of a second magnitude, wherein said first magnitude is at least twice said second magnitude so as to cause a shock wave in the gas-liquid flow downstream of said fluid outlet apparatus and atomizing of the liquid portion of said outflow into microscopic droplets thereby to form a liquid mist suspended in the gas portion of said outflow,
• and wherein said fluid outlet apparatus defines a fluid outlet port, said fluid outlet apparatus including at least one interior nozzle member having an interior diameter wherein said preselected distance is not greater than 50 times said internal diameter, said interior nozzle member arranged to provide an outflow of sterile liquid, each said interior nozzle member including:
• a rear portion configured to fit over said interior nozzle member and arranged to fit over said interior nozzle member so as to define a passageway therebetween for gas flow;
• a waist portion defined by a forward tapering of said rear portion;
• a front portion defining an opening and tapering rearwardly towards said waist portion,
• wherein said passage way is formed so as to be increasingly constricted towards said front portion of said nozzle member, such that said gas flow passing through said passageway is accelerated to at least sonic velocity,
• and wherein said front portion widens toward said opening thereof such that said accelerated gas flow expands and thus undergoes a drop in pressure to a pressure which is sub-atmospheric, such that when said nozzle opening is brought to within a pre-selected distance from the skin surface to be abraded, at least a portion of the epidermis is separated from the skin surface.

Apparatus for dermal abrasion, which includes:

• a container for a sterile liquid;
• a fluid delivery head having a liquid entry port and a gas entry port, fluid outlet apparatus, and valve apparatus located between said entry ports and said fluid outlet apparatus and for selectably permitting respective liquid and gas flows from said entry ports to said fluid outlet apparatus;
• liquid conduit apparatus extending between a liquid inlet located within said container and a liquid outlet connected to said liquid entry port of said delivery head;
• gas conduit apparatus extending between a gas inlet and a gas outlet, wherein said gas inlet is connected to a source of pressurized gas and said gas outlet is connected to said gas entry port of said delivery head, and wherein said gas conduit apparatus is connected to said container via an intermediate outlet port;
• and
• apparatus for selectably exposing said source of sterile liquid to a flow of pressurized gas flowing from said gas inlet to said gas outlet and into said gas entry port of said fluid delivery head, thereby to pump said sterile liquid along said liquid conduit apparatus, from said inlet to said outlet, and into said liquid entry port of said fluid delivery head,
• wherein said fluid outlet apparatus includes at least one gas-liquid combining member arranged to receive said gas and liquid flows and to combine them into a gas-liquid outflow which is operative to exit said fluid outlet apparatus in the form of at least one sterile liquid mist jet suspended in a high velocity gas stream, and wherein each jet is operative, when brought to within a preselected distance from the skin surface to be abraded, to separate therefrom at least a portion of the epidermis,
• wherein said gas flow exits said valve apparatus into said gas-liquid combining member at a pressure of a first magnitude and said combining member is operative to cause a pressure drop in the gas flow therethrough such that the pressure of the gas-liquid outflow downstream of said fluid outlet is of a second magnitude, wherein said first magnitude is at least twice said second magnitude so as to cause a shock wave in the gas-liquid flow downstream of said fluid outlet apparatus and atomizing of the liquid portion of said outflow into microscopic droplets thereby to form a liquid mist suspended in the gas portion of said outflow,
• and wherein said fluid outlet apparatus defines a fluid outlet port, said fluid outlet apparatus including at least one interior nozzle member having an interior diameter wherein said preselected distance is within a range of 1 to 5 times said internal diameter, said interior nozzle member arranged to provide an outflow of sterile liquid, each said interior nozzle member including:
• a rear portion configured to fit over said interior nozzle member and arranged to fit over said interior nozzle member so as to define a passageway therebetween for gas flow;
• a waist portion defined by a forward tapering of said rear portion;
• a front portion defining an opening and tapering rearwardly towards said waist portion,
• wherein said passage way is formed so as to be increasingly constricted towards said front portion of said nozzle member, such that said gas flow passing through said passageway is accelerated to at least sonic velocity,
• and wherein said front portion widens toward said opening thereof such that said accelerated gas flow expands and thus undergoes a drop in pressure to a pressure which is sub-atmospheric, such that when said nozzle opening is brought to within a pre-selected distance from the skin surface to be abraded, at least a portion of the epidermis is separated from the skin surface.