RU198011U1 - DEVICE FOR PHOTODYNAMIC THERAPY - Google Patents

Abstract

The utility model relates to medical equipment, namely, equipment for solving experimental problems of photodynamic therapy. The device comprises a housing with controls, an LED emitter, a unit for adjusting the intensity of optical radiation, a forced air cooling unit in the form of fans installed inside the housing, a power supply. A restrictive diaphragm is made on the lower surface of the housing. The LED emitter contains a mounting surface on which seven LED assemblies are mounted, with one LED assembly mounted horizontally in the center, and the remaining six are arranged in a circle with an inclination at an angle of 30 degrees towards the central assembly. The device comprises a unit for adjusting the intensity of optical radiation connected to the LED emitter and the fan unit. An LED emitter is mounted in a housing above the limiting diaphragm. The technical result is to increase the power density at the facility, reducing weight and reducing the size of the device. 6 c.p. f-ly, 3 ill.

Description

The utility model relates to medical equipment for solving experimental problems of photodynamic therapy (PDT), relates to a device for conducting photodynamic therapy, which can be used, in particular, to conduct studies of the photodynamic activity of photosensitizers in small laboratory animals.

Today, when conducting therapeutic irradiation procedures on the surface layers of biological tissue, in particular PDT procedures, relatively expensive lasers in the range of 600–700 nm with an output power of optical fiber from 1 to 10 W are widely used (http://www.alcommedica.ru/info /products/dlya_fotodinamicheskoj_terapii/new_body.html)(http://www.biospec.ru/_LPhT_r.html)(Brancaleon L., Moseley N. Laser and non-laser light sources for photodynamic therapy // Lasers Med Sci. 2002. V. 17, No. 3. P. 173-86).

At the same time, superbright LED assemblies that have appeared on the market make it possible to create compact, inexpensive sources of incoherent optical radiation in the range of 600-1000 nm, not inferior to lasers in terms of output power.

A device is known (see http://www.biospec.ru/2/UFPh_r.pdf) UFF-630 / 675-01-BIOSPEC designed for photo dynamic therapy of surface formations and fluorescence monitoring. The device is based on light-emitting diodes of increased brightness. The LED radiation forms a light spot on the irradiated surface in the form of a circle with a diameter of about 10 cm. The total optical power of the system is at least 1500 mW, the radiation power density is at least 40 mW / cm ² .

The disadvantage of the described device is the high unevenness of the intensity distribution in the irradiation zone and a significant decrease in the radiation power density at a distance of 2.5 cm from the center (spot) - up to 60%, as well as the large weight and size of the control units.

A device for fluorescence diagnostics and photodynamic therapy is known (N. Momchilova, I. Bliznakovaa ,, E. Borisovaa, P., Troyanovab, L. Avramova Development of Low-Cost Photodynamic Therapy Device // Proceedings of the International School and Conference on Optics and Optical Materials, ISCOM07, Belgrade, Serbia, September 3-7, V. 112, No. 5. 2007) based on LEDs with a central wavelength of 635 nm (for therapeutic use) and 405 nm (for diagnostic applications). The geometry of the LEDs allows you to create a light spot on an object measuring 40 × 50 mm and achieve a radiation power density within the boundaries of this spot 40 mW / cm ² . Flexible mechanical levers are attached to the irradiating head of the device, which allows you to bring light to a point difficult on the surface of human skin in terms of anatomy.

The closest in technical essence and the ensured technical result to the proposed utility model is the medical device “Fara” manufactured by Atkus LLC (http://www.atcus.ru/application.php?ID=11), taken as the closest analogue (prototype )

The prototype device comprises a housing, on the front and rear panels of which control elements are placed, an LED emitter generating light radiation, a control unit, a forced cooling system, a power supply. The LED emitter is an optical-mechanical assembly of several super-bright LEDs located on the radiator, with a common focusing reflector. The control unit consists of two parts - the LED current control unit and the LED protection unit. In this case, the LED emitter is mounted on a tripod and connected to the control unit using an electric wire. The forced cooling system consists of fans connected to a control unit that automatically adjusts their speed, maintaining optimal temperature conditions. The device is intended for use as powerful sources of light radiation of a narrow spectrum, in medical institutions of a wide profile in the field of photodynamic therapy, cosmetology, sterilization, etc.

However, the prototype device is not without drawbacks:

- firstly, the large total weight of the device - the weight in the complete set is 8.5 kg;

- secondly, the significant dimensions of the LED emitter - 108 × 180 mm;

- thirdly, the radiation power density up to 120 mW / cm ² created at the facility is insufficient for a number of tasks.

The objective of the utility model is the improvement of the device for conducting photodynamic therapy.

The technical result from the use of the proposed utility model is to increase the power density at the facility, reduce weight and reduce the dimensions of the device.

This object is achieved in that in a device for conducting photodynamic therapy comprising a housing with controls, an LED emitter, a forced air cooling system installed inside the housing, a power supply, a limiting diaphragm is made on the lower surface of the housing, the LED emitter contains a mounting surface on which seven LED assemblies are fixed, one LED assembly is installed horizontally in the center, and the six remaining are arranged in a circle with an inclination at an angle of 30 degrees towards the central assembly, a fan block is used as a forced air cooling system, including two fans connected in parallel, an additional device contains a unit for adjusting the intensity of optical radiation, while the unit for adjusting the intensity of optical radiation is connected to the LED emitter and the fan unit, the LED emitter is mounted in a housing above restrictive diaphragm; a unit for adjusting the intensity of optical radiation is made on the basis of a pulse generator with a variable duty cycle, which is assembled according to a standard circuit with a variable resistor on logic elements and connected to the base of a field-effect transistor with a control key; each LED assembly includes four superbright crystal LEDs with integrated collimating optics model LZ4-00R108 manufactured by LED Engin, Inc. or an analog emitting in the spectral range of 630-650 nm; the fan block uses standard small-sized DC DC fans with dimensions of 50x50x10 mm, operating voltage of 12 V, current consumption does not exceed 0.1 A, power consumption - no more than 2.40 W, or their analogue; as the power supply, a portable power supply with an output voltage of 12 V, with a rated output power of 100 V × A, or an analogue is used; as a control element, a handle is used, connected to a variable resistor of the pulse generator, around which on the surface of the housing there is a scale for adjusting the output intensity, calibrated to a range from 0 mW / cm ² to 300 mW / cm ² in increments of 50 mW / cm ² ; additionally contains height-adjustable removable support legs.

In FIG. 1 is a schematic illustration of a device for conducting photodynamic therapy.

In FIG. 2 is a bottom view of a device for conducting photodynamic therapy.

In FIG. 3 shows an electrical diagram of a device for conducting photodynamic therapy.

The apparatus for conducting dynamic photo therapy in FIG. 1-3 contains:

1 - case;

2 - limiting aperture;

3 - unit for adjusting the intensity of optical radiation;

4 - pulse generator;

5 - variable resistor;

6 - logical elements;

7 - field effect transistor;

8 - LED emitter;

9 - mounting surface;

10 - LED assembly;

11 - fan unit;

12 - power supply;

13 - connector for connecting the power supply;

14 - handle.

The housing 1 is made with controls.

On the bottom surface of the housing 1 is made limiting diaphragm 2 in the form of a hole.

Inside the housing 1, a unit for adjusting the intensity of optical radiation 3, an LED emitter 8 and a fan unit 11 are installed.

The unit for adjusting the intensity of optical radiation 3 is made on the basis of a pulse generator 4 with a variable duty cycle, which is assembled according to a standard circuit with a variable resistor 5 on the logic elements 6 and connected to the base of the field-effect transistor 7 with a control key.

The LED emitter 8 includes a mounting surface 9 on which seven LED assemblies 10 are mounted, one of which is mounted horizontally in the center, and the remaining six are mounted in a circle with an inclination at an angle of 30 degrees towards the central LED assembly.

The unit for adjusting the intensity of the optical radiation 3 is connected in series with the LED emitter 8 and the fan unit 11.

LED emitter 8 is installed in the housing 1 above the limiting diaphragm 2.

The fan block 11 consists of two parallel-connected small-sized fans.

Each LED assembly 10 includes, for example, four superbright crystal LEDs with integrated collimating optics model LZ4-00R108 manufactured by LED Engin, Inc. or an analog emitting in the spectral range of 630-650 nm.

The fan block 11 uses standard small-sized DC DC fans with dimensions of 50 × 50 × 10 mm, an operating voltage of 12 V, a current consumption of not more than 0.1 A, a power consumption of not more than 2.40 W, or an analog thereof.

As the power supply 12, a portable power supply with an output voltage of 12 V, with a rated output power of 100 V × A, or an analogue is used.

As a control element, a handle 14 is used, connected to a variable resistor 5 of the pulse generator 4, around which an output intensity adjustment scale is calibrated on the surface of the housing 1, calibrated to a range from 0 mW / cm ² to 300 mW / cm ² in increments of 50 mW / cm ² .

Additionally, height-adjustable, removable support legs are included.

The assembly of the proposed utility model is as follows.

A case 1 of 100 × 110 × 55 mm in size is made from sheet duralumin. At the same time, a circular hole is made in the lower surface of the housing 1 for the restricting diaphragm 2, one of the side surfaces of the housing 1 is replaced with a perforated aluminum plate to ensure the removal of the heated air flow from the housing.

A unit for adjusting the intensity of optical radiation 3 is made. For this, a pulse generator 4 with a variable duty cycle is manufactured. The pulse generator 4 is assembled according to the standard scheme with a variable resistor 5, on the logic elements 6, for example, type "2-AND-NOT." The pulse generator 4 is connected to the base of the field-effect transistor 7 with a control key. Connections are performed by their mounting conductors.

A LED emitter 8 is made. For this, seven LED assemblies 10 are arranged on a horizontal mounting surface 9 according to a specially calculated geometry. Moreover, one LED assembly is installed horizontally in the center, and the remaining six are arranged in a circle with an inclination at an angle of 30 degrees towards the central assembly. Using the mounting wires, the LED assemblies 10 are connected in parallel with the optical radiation intensity adjustment unit 3. For example, LED assemblies 10 are used, each of which contains four super bright crystal LEDs with integrated collimating optics of the LZ4-00R108 model manufactured by LED Engin, Inc. or their analogue, emitting in the spectral range of 630-650 nm (the spectral width of the emission band at half maximum is not more than 20 nm).

A fan block 11 is made by connecting in parallel, for example, two standard small-sized DC DC fans of the RQD 5010MS model or their equivalent, having dimensions of 50 × 50 × 10 mm, an operating voltage of 12 V, the current consumption of each does not exceed 0.1 A, the total power consumption of the unit 10 fans - no more than 2.40 watts.

Inside the housing 1, a unit for adjusting the intensity of optical radiation 3, an LED emitter 8, a block of small-sized fans 11 are installed.

In this case, the LED emitter 8 is installed above the limiting diaphragm 2 made in the lower surface of the housing 1, and the fan block 11 opposite the perforated plate made on one of the side surfaces of the housing 1.

The electric intensity control unit 3 of the optical radiation 3, the LED emitter 8, the fan unit 11 and the power supply 12 are connected by electric wires through the connector 13 on the housing 1.

On the upper surface of the housing 1, a handle 14 is installed, mechanically connected to a variable resistor 5 of the pulse generator 4. Around the handle on the surface of the housing 1, an output intensity adjustment scale calibrated for a range from 0 mW / cm ² to 300 mW / cm ² with a step of 50 mW is performed / cm ² .

As the power supply 12 use, for example, a commercially available standard portable unit with an output voltage of 12 V, with a rated output power of at least 100 V × A, size 150 × 70 × 40 mm or an analogue.

The total weight of the device assembly is not more than 800 g. The case weight is not more than 400 g, the weight of the device’s power supply unit is not more than 300 g.

The proposed utility model works as follows.

The irradiated surface is placed close to the lower plane of the housing 1 in the opening of the output restrictive diaphragm 2. In this case, the LED emitter 8 with the mounting surface 9, on which the LED assemblies 10 are mounted, is placed strictly above the irradiated surface.

The device is turned on by supplying voltage to the power supply 12, for example, by attaching a plug connector to a socket, or by applying voltage to the socket using a push button switch. In this case, the supply voltage from the output of the power supply unit 12 is supplied to all elements of the electrical circuit of the device located in the housing 1. The duty cycle of the pulses of the pulse generator 4 is controlled using a variable resistor 5, using the handle 14 located on the upper surface of the housing 1. Pulses from the generator pulses 4 open the control key, assembled on a powerful field-effect transistor 7. The control key, assembled on a powerful field-effect transistor 7, supplies power to the LED assemblies 10 of the LED emitter 8. In this case, the LED emitter 8 with LED assemblies 10 forms a combined radiation pattern determined by the superposition of the diagrams directivity of individual assemblies. The location of the LED assemblies 10 on a common mounting surface 9 according to a specially calculated geometry ensures a high uniformity of the intensity distribution while increasing the power density. The block of small fans 11 provides forced air cooling of the mounting surface 9, containing the LED assembly 10 and their stable low-temperature mode of operation. Using the handle 14 located on the upper surface of the housing 1, smoothly adjust the output intensity in the range from 50 to 300 mW / cm ² .

The time for the device to enter the operating mode is no more than 1 min, intensity fluctuations in 1 hour of operation at maximum intensity - no more than 5%.

The PDT procedure is carried out during the estimated exposure time necessary to obtain the desired dose density on the surface of the object, usually no more than 20 minutes.

The proposed design of the utility model provides an increase in power density at the facility while reducing weight and reducing the dimensions of the device.

So the working diameter of the light spot on the surface of the object is not less than 35 mm with an uneven distribution of intensity in the working diameter of the light spot not more than 10%, and the maximum power density not less than 300 mW / cm ² , which completely covers the dose density used in PDT from 50 to 300 J / cm ² when the exposure time is not more than 20 minutes. Moreover, the intensity in the operating mode is 2-3 times higher than that declared in the characteristics of the closest analogue (300 mW / cm ² versus 100-120 mW / cm ² ). The height of the developed device is four times less (55 mm versus 180 mm) than the closest analogue with the approximate equality of the width and length of the structures, the mass is 10 times lighter than the prototype (0.8 kg versus 8.5 kg).

The ability to use height-adjustable removable support legs allows you to use the device without the use of external tripods or other holding devices. If necessary, the device can also be mounted on an external rotary tripod with an adjustable angle of inclination and fixation of position.

Claims (7)

1. A device for conducting photodynamic therapy, comprising a housing with controls and forced air cooling, an LED emitter, a power supply, characterized in that a limiting diaphragm is made on the lower surface of the housing, the LED emitter contains a mounting surface on which seven LED assemblies are mounted, wherein one LED assembly is installed horizontally in the center, and the remaining six are arranged in a circle with an inclination at an angle of 30 ° towards the central assembly, a fan unit is used for forced air cooling, the device further includes an optical radiation intensity adjustment unit, and an optical radiation intensity adjustment unit connected to the LED emitter and the fan unit, the LED emitter is installed in the housing above the limiting diaphragm. 2. The device according to p. 1, characterized in that the unit for adjusting the intensity of optical radiation is made on the basis of a pulse generator with a variable duty cycle, which is assembled according to a standard circuit with a variable resistor on logic elements and connected to the base of a field-effect transistor with a control key. 3. The device according to claim 1, characterized in that each LED assembly includes four superbright crystal LEDs with integrated collimating optics of the LZ4-00R108 model manufactured by LED Engin, Inc. or an analog emitting in the spectral range of 630-650 nm. 4. The device according to claim 1, characterized in that the fan block uses two parallel-connected standard small-sized DC DC fans having dimensions of 50 × 50 × 10 mm, operating voltage of 12 V, current consumption does not exceed 0.1 A, power consumption is no more than 2.40 W, or their equivalent. 5. The device according to claim 1, characterized in that a portable power supply unit with an output voltage of 12 V, with a rated output power of 100 VA, or an analogue is used as the power supply unit. 6. The device according to p. 1, characterized in that the control element is a handle connected to a variable resistor of the pulse generator, around which an output intensity adjustment scale calibrated to a range from 0 mW / cm ² to 300 mW / cm ² in increments of 50 mW / cm ² . 7. The device according to p. 1, characterized in that it further comprises a height-adjustable removable support legs.

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