WO2026017789A1

WO2026017789A1 - A device and method for treating wounds

Info

Publication number: WO2026017789A1
Application number: PCT/EP2025/070472
Authority: WO
Inventors: Janus BEIERHOLM
Original assignee: Inwound Aps
Current assignee: Inwound Aps
Priority date: 2024-07-18
Filing date: 2025-07-17
Publication date: 2026-01-22
Anticipated expiration: 2027-01-18

Abstract

The present invention relates to a device and a method used for treating wounds, such as chronic wounds. The device comprises a light source (14-16) emitting a first light at a wavelength and a light intensity which influence bacterial-growth negatively, and an end effector (1) comprising a front surface facing the wound to be treated during operation, the front surface of the end effector (1) is configured to maintain a constant distance to the wound, and the light sources (14-16) are distributed over the front surface and orientated to emit light onto an area to be treated.

Description

A device and method for treating wounds

Technical field

The present invention relates to a medical device used for treating wounds such as chronic wounds. In particular, the present invention relates to a device for treating chronic wounds through light-based treatment.

The invention further relates to a method of treating wounds using the device mentioned above.

Background of the invention

Chronic wounds account for 2-5% of the total healthcare spending in the US and EU and result in an amputation every 30s. At any given time about 2% of the western population suffer from chronic wounds. To make matters worse, chronic wounds are strongly correlated with diabetes rates and the rise of the aging population. As a result, there is a dramatic increase in new chronic wounds which pushes the limits of our healthcare systems. Since the wounds are typically located on the lower legs and feet, the patient's mobility is often impaired, but they still need to find their way to clinics or hospitals on a weekly or bi-weekly basis to get their wounds treated. Chronic wound care is relatively simple, but it is a manual and labour-intensive practice, often done by doctors rather than nurses even in simple cases. Nurses' skill and expertise are therefore left underutilized in the current wound care practice. In addition, treatment hasn't been modernized with automatization, artificial intelligence or digitalisation.

Reduced blood flow (worsened by diabetes) and a reduced immune response (worsened by old age) slow down the healing process and make infections more likely. Bacteria cannot be avoided and works its way into the wound from the skin surface during everyday activities. Bathing, sweating, or touching transfers the bacteria into the wound bed, where festering bacteria then produces a biofilm that sticks to surrounding tissue and protects early bacterial colonies. These bacteria colonies may later reorganize and produce proinflammatory factors that perpetually trap the wound in the inflammatory stage of wound healing.

A biofilm is a microbial colony encased in a polysaccharide matrix attaching to a wound surface. This affects the healing potential of chronic wounds due to the production of destructive enzymes and toxins, which can promote a chronic inflammatory state within the wound. Removing biofilm is extremely difficult, as the film firmly attaches to surrounding tissue, is resistant to antibiotics and biocides, can't be penetrated by antibiotics and biocides, and evades the body's local immune response. Almost all chronic wounds contain some form of bacterial infection that can produce biofilm. These bacteria are often found on the surface of the wound bed and up to 0.5 mm into the tissue. This problem is growing in pace with the increasing emergence of multidrug-resistant Pseudomonas Aeruginosa and Staphylococcus aureus, with P. aeruginosa being the most common organism in all wounds and is significantly more common in lower extremity wounds like venous leg ulcers (VLUs).

One method of skin disorder treatment is disclosed in US 2002/0173833 Al, wherein a light source emits a violet/blue light beam with a spectral band of 400-450 nm. The light source is positioned on a moveable support structure so that the position, angle and distance relative to the area of interest on the patient's body. However, this solution is specifically designed for acne treatment and is not suitable for wound healing.

EP 3632507 Al discloses another method of skin disorder treatment, where an image and other parameters of the patient's body are captured using a camera and other sensors. Artificial intelligence and object detection are used by the control unit to identify areas that need treatment and to select a treatment profile. A light source unit emits a light beam with a spectral range of 100-1600 nm onto a selected area in accordance with the selected treatment profile.

In one embodiment of EP 3632507 Al, the light source is adapted to emit a pulsed, visible light signal with a spectral range of 400-1200nm and a frequency range of 1Hz to 1MHz. Filters are used to target specific structures and chromophores. However, this solution still has some shortcomings and limitations regarding wound healing.

US 2022/0409918 Al discloses a system and method of wound healing, where a handheld device is positioned over the wound to form an enclosed treatment chamber. A laser source is arranged at the top of the device, where the control unit controls the wavelength, light intensity and pulse duration of the emitted laser beam based on the measured signals from various sensors and thermal detectors arranged within the device. Nozzles are used to apply debridement liquids to the wound and a vacuum pump connected to a suction outlet is used to remove debris and spend liquid from the wound.

An optimal laser beam with a wavelength of 2940 nm and a pulse duration of 200-300 ps and a laser intensity below 10 ^J/_cm ² is particularly advantageous to remove necrosed wound tissue and/or infection.

DE 202018005328 U1 discloses a method of wound treatment, where the LED light source is positioned about 1 cm from the skin surface and emit a blue and red light with a wavelength of 420-500 nm and 600-750 nm and further a violet light with a wavelength of 400-420 nm. KR 20180131247 A discloses a sterilizing device comprising a UV light source emitting UV rays and a distance sensor, where the light intensity is determined based on the measured distance. The UV light is selected to target bacteria resistant to antibiotics like MRSA and VRE.

CN 11731121 A discloses a light therapeutic apparatus comprising a main control box, a bendable arm and a light source unit arranged at the end of the arm. The light source emits a UVC light beam with a wavelength of 222 nm and then emits an IR light beam and red and blue light beams. A camera is arranged on the light source unit and used to capture images of the wound.

US 2019/0060495 Al discloses a similar light therapeutic apparatus, which also emits a UVC light beam together with ozone onto the wound to sterilize the wound. The UV light is selected to target bacteria resistant to antibiotics like MRSA.

Object of the invention

One object of the invention is to provide a device and method that overcomes the shortcomings of the abovementioned prior art or at least provide an alternative solution.

One object of the invention is to provide a device and method that promotes wound healing.

One object of the invention is to provide a device and method that reduces the treatment time and allows for a more versatile usage.

Summary of the invention

The device according to the present invention provides a non-invasive, safe and efficient treatment which may be performed by non-specialized personnel. The light treatment performed by the present device is less painful than traditional treatments and may be performed more often and may therefore result in a faster recovery of the patient. The present system may advantageous be configured as an automatic system which is controlled via the control unit.

One object of the present invention is achieved by a device for treating wounds, preferably chronic wounds, comprising

- an end effector having a front surface configured to face a wound to be treated during operation,

- at least one light source configured to emit at least a first light with a wavelength and a light intensity that influences bacterial growth negatively,

- a control unit connected to the end effector and configured to control the operation of the at least one light source, - wherein the front surface of the end effector is configured to maintain a constant distance to the wound, and the light sources are distributed over the front surface and orientated to emit lights onto an area to be treated, wherein the least one light source is configured to emit the first light as a pulsed light with a predetermined pulse frequency and/or pulse duty-cycle.

This provides a medical device for wound treatment that reduces the spread of microorganism and increases the speed of the treatment. The present system allows for a fully automatic and guided treatment with less or reduced sense of pain compared to traditional treatments. The present device can be operated by non-specialized personnel, such as medical practitioners, thereby reducing the workload of doctors.

Thus, a first aspect of the present invention relates to a light emitting device for treating wounds comprising a light source emitting light at a wavelength and an intensity which influence bacterial-growth negatively, and comprising an end effector comprising a front surface facing the wound to be treated during operation, wherein the front surface of the end effector is configured to maintain a constant distance to the wound, and the light sources are distributed over the front surface at an area corresponding to the area to be treated.

The present device comprises at least a control unit connected to an end effector which comprises an arrangement of light sources located at a front surface. The end effector is moveable so that it can be positioned and orientated relative to a wound on a body, e.g. a human body. The light source arrangement is configured to emit lights onto an area of treatment, wherein electrical power to the light sources is provided via a power supply system. The control unit may be arranged in a main box, where the control unit may be interconnected to the end effector via a mechanical arm. This allows the personnel to easily set up the device before the treatment.

The light sources are adapted to emit a first light that influences the bacterial growth negatively. This also causes a thermal damage in the specific light absorbing proteins in the bacteria. This triggers a reactive oxygen species (ROS) cascade leading to the destruction of the bacteria cell membrane, killing the bacteria. Different bacteria, or groups of bacteria, react to different wavelengths of light. Hence the wavelength and light intensity of the first light is tuned to target specific bacteria in the wound.

The control unit is adapted to generate a pulsed first light emitted from the light sources having a predetermined pulse frequency and pulse duty-cycle. The profile of the pulsed light is selected so that the first light penetrates deeper into the tissue compared to emitting a constant light. For example, the pulse profile may be selected so that the first light penetrates about 1 cm into the tissue. This allows the first light to target bacteria cells located before other cells. This may be used in applications in which singlet oxygen is formed in the cells, wherein the ROS cascade has a half-life time of about IO^-5 sec.

In one embodiment, the at least one light source either

- comprises a plurality of light sources distributed or controlled to emit lights over the treated area, or

- comprises a single or a few light sources in combination with a light distribution device, such as optical lenses, to emit lights over the treated area.

The configuration of the light source arrangement may be selected based on the type of light sources used in the end effector. The individual light sources may be arranged at the front surface so that they directly focus the emitted radiation onto the treatment area without the use of reflector or optical lenses. Alternatively, a reflector, an optical diffuser or optical lenses may be arranged in front of the individual light sources to focus the emitted radiation onto the treatment area.

Thus, according to any embodiment of the first aspect, the light source may either comprise a plurality of light sources distributed or controlled to emit light over the area to be treated, or the light source may comprise a single or a few light sources in combination with a light distribution device such as an optical lenses to emit light over the area to be treated.

Further, the front surface of the end effector may be covered by a protective, transparent element. The protective element may be arranged in front of at least the light sources. Alternatively, a single protective element may cover both the light sources, the cameras and optionally other components arranged at the front surface. Alternatively, individual protective elements may be arranged relative to the light sources, the cameras and/or other components of the front surface.

According to any embodiment of the first aspect, the front surface of the end effector (1) is protected by a cover surface which cover surface is transparent for relevant radiation such as a germanium window or a Gallium-Arsenide window.

In one embodiment, the device further comprises a cooling system configured to cool the treated area during use, preferably at least one nozzle is connected to a fluid supply unit which is configured to introduce a fluid onto the treated area, and preferably the fluid is air and the nozzle is an air nozzle.

The device may further comprise a cooling system configured to cool the tissue at the treatment area. The cooling system may comprise a fluid supply unit connected to one or more nozzles arranged at the end effector. The fluid supply unit may be enclosed in the main box together with the control unit. Tubes may interconnect the fluid supply unit to the respective nozzles at the front surface. The control unit may be configured to control the operation of the cooling system during use. This allows a flow of fluid to pass over the wound, thereby reducing risk of thermal damage. Hence a higher energy can be outputted by the light sources to ensure that harmful bacteria is eradicated.

Preferably, the fluid supply unit may comprise an air pump and air filters connected to air nozzles located at the front surface of the end effector. The air is cleaned by the filters to avoid cross contamination of the wound, where the clean air is blown over the treatment area while the treatment is being applied. Alternatively, the fluid may be another gas or partly a gas, such nitrogen or a water-aerosol. Hence, no need for an enclosed treatment chamber and a vacuum pump to remove the debris and dirty fluid.

According to any embodiment of the first aspect, the device may comprise cooling means configured to cool the light receiving surface during use, preferably the cooling means comprises one or more such as two or more nozzles which is/are configured to provide a flow of fluid and which nozzle(s) is/are positioned in close proximity to the light source, preferably the fluid is a gas or partly a gas such as air or nitrogen or a water-aerosol, preferably the nozzle(s) is/are positioned along the outer perimeter of the front surface of the end effector i.e. the nozzles may be positioned closer to the periphery of the front surface than the light-emitting units.

In one embodiment, the device further comprises at least one camera connected to a control unit and configured to capture an image of the wound, wherein the control unit is configured to at least determine the presence of a bacteria, a temperature of the wound, and/or a blood flow of the wound based on the captured image data.

Cameras may be used to capture different types of image data of the wound, wherein the control unit may analyse the image data to determine one or more parameters relating to the conditions of the wound. The respective cameras may be grouped together at the front surface or arranged at different positions.

A first camera, e.g. a thermal camera, may be used to measure the temperature of the wound in a non-contact manner. A second camera, e.g. a fluorescent camera, may be used to detect the fluorescent levels emitted by bacteria in the wound. A third camera, e.g. a haemoglobin camera, may be used to measure the blood flow of the wound. The total number of cameras may vary depending on the desired application and configuration of the device. The image data from the respective cameras may be processed by a processor in the control unit and the image data along the parameters may be stored in a memory unit in the control unit. The data may be combined to form a historic set of data relating to the healing process of the wound. The data may also be used to determine the optimal treatment of the wound.

In one embodiment, the device further comprises a distance sensor connected to a control unit and configured to measure the distance between the front surface of the end effector and the wound.

The end effector may be maintained at a distance from the wound by mechanical means, e.g. spacer rods, arranged on the end effector. The mechanical means may have a fixed structure or an adjustable structure. This ensures that the light sources are positioned at the optimal distance from the wound. Alternatively, a distance sensor may be arranged at the front surface of the end effector. The distance sensor may be connected to the control unit, which calculates the distance between the front surface and the wound based on the sensor output.

This provides a more uniform energy distribution over the treatment area compared to a traditional parabolic energy distribution having a higher energy output at the centre of the affected area.

In one embodiment, the end effector comprises a plurality of light-emitting units, such as diodes or lamps, which light-emitting units are placed in a circular or in a polyangular pattern around a central part of the front surface of the end effector, and preferably the light-emitting units are divided into one or more groups that are controlled independently by the control unit.

The front surface of the end effector may be divided into a central part and a surrounding outer part. The end effector may comprise a plurality of light emitting units distributed evenly along the outer part in the circumference direction. The individual light emitting units may be divided into one or more groups and interconnected so they can be controlled independently by the control unit. This allows the control unit to adjust the emitted light intensity of each group to achieve the uniform energy distribution mentioned above.

If light emitting diodes, LEDs, are used as the light source, then they may be arranged on a printed circuit board shaped to form the outer part of the front surface. If light emitting lamps are used as the light source, then they may be distributed along the circumference of the outer part. The individual light sources may together form a circular or polyangular pattern depending on the desired configuration of the end effector. Thus, according to any embodiment of the first aspect, the end effector may comprise lightemitting units such as diodes or lamps, which light-emitting units preferably are placed in a circular or in a polyangular pattern around a central part of the front surface of the end effector, and preferably, the light-emitting units create a flattish irradiance profile throughout the treatment distance and allow one or more cameras to be placed at the centre.

In a further embodiment, at least one camera is arranged within the central part of the end effector.

The various cameras and sensors used in the end effector may be arranged within the central part. Optionally, the nozzles of the cooling system may be arranged within the outer part, preferably closer to the edge of the front surface than the light sources. Alternatively, the nozzles may be positioned amongst the light sources. This allows for a more optimal placement of the cameras and sensors compared to other traditional end effectors.

In one embodiment, the light-emitting units are configured to emit lights over a treatment area of minimum 2 cm² and/or of maximum 15 cm².

The present arrangement of the light sources along the outer part of the end effector allows for a larger treatment area compared to other traditional treatment devices. Further, it also allows for a higher total energy output and thus a more efficient treatment of the bacteria in the wound. The treatment area may advantageously be a minimum of 2 cm², a minimum of 4 cm², a minimum of 8 cm², or a maximum of 15 cm².

According to any embodiment of the first aspect, the device may comprise a plurality of and/or a distribution of light source(s) positioned along the front surface of the end effector configured to distribute emitted light equally over an area of light a surface to be treated, preferably of minimum 2 cm², or minimum 4 cm²' or minimum 8 cm², and/or over an area a surface to be treated of at most 15 cm2, where "equally" means that an amount of energy per second per cm² suitable to obtain treatment for the area of the wound is transferred to the surface to be treated.

The method according to the present invention takes advantage of the abovementioned device which need not be operated by a doctor or specialized nurse which is advantageous. The present method provides a more efficient and/or faster treatment compared to traditional methods. The method may advantageous be performed using an automated process, thereby reducing the workload of doctors. This also reduces the spread of microorganism and increasing the speed of treatment. One object of the present invention is achieved by a method of treating wounds, comprising

- providing a device as described above,

- positioning the end effector relative to a wound of a body,

- selecting a pulse frequency and/or pulse duty-cycle of the first light via the control unit,

- activating the light sources and emitting at least the pulsed first light onto an area of treatment for a predetermined time period, after which the light sources are turned off.

The configuration of the present device allows the operator to easily move the end effector into position relative to the wound intended for treatment. The mechanical arm may be a robotic arm or a bendable arm, which is able to maintain its position for at least 1 minute, preferably at least two minutes.

A user interface, e.g. a computer terminal or a touchscreen, of the control unit may be used to input a pulse frequency and a duty-cycle of the first light. The operator may manually enter these variables or select these from a list. Alternatively, the operator may initially capture an image of the wound, where the control unit may be configured to determine the type of bacteria located in the wound based on at least the thermal image data. This allows even non-specialized personnel to tune the emitted lights to the intended application and bacteria found in the wound.

The optional treatment information for different bacteria and/or wounds may be stored within the control unit, where the operator may select the optimal treatment based on the stored information.

Thus, according to any embodiment of the first aspect, the device may comprise means such as a mechanical arm configured to maintain a constant position of a front surface of the end effector facing the light receiving surface for a period t, where t > 60 seconds, or t > 120 seconds.

The present method may be performed in an automatic process, thus reducing the workload and treatment time.

In one embodiment, the first light is centred around a wavelength of 405 nm with a narrow band range, preferably a maximum band range of 5 nm or of 2nm.

Blue light with a wavelength of 405nm is particularly advantageous for treatment of human bodies as there is no target for the 405 nm light in the human cells. Therefore, it only destroys the bacteria cells while leaving the human cells intact. The emitted light triggers a reactive oxygen species (ROS) cascade leading to the destruction of the bacteria cell membrane, thus killing the bacteria. This also causes a thermal damage in the affected bacteria.

Hence, according to any embodiment of the first aspect, the light source(s) may emit light at a wavelength of 405 nm to influence bacterial growth negatively.

By applying a light centred at 405nm with a very narrow band range, e.g. of a maximum of 5 nm or 2 nm, allows as many bacteria as possible to be killed while reducing the thermal damage to the tissue. Any light applied outside of this band range is less effective for killing bacteria but delivers the relative same amount of tissue damage.

In one embodiment, the lights emitted from the light sources have a substantially uniform energy distribution over the treated area, preferably at an averaged light intensity of minimum 50 7cm² and/or of maximum 200 7cm².

The control unit may use the measured distance as input for adjusting the emitted light intensity of the respective light sources so that they provide a substantially uniform energy distribution over the treatment area. The control unit may calculate an average light intensity for the activated light sources. Maximum and minimum threshold values may define a range in which the emitted light intensity may vary during treatment. If the light intensity of one or more light sources moves outside the range, then the control unit may turn the light sources off as a safety measure. This ensures a uniform energy application that kills as many bacteria as possible while avoiding hot spots that might otherwise have caused thermal damage to the surrounding cells in the body.

The present light source arrangement allows for a higher energy output and thus a higher total light intensity per day compared to other traditional light treatment methods. The light intensity may be selected within a range of 25-300 7cm², e.g. 50-2007cm², 75-1807cm² or 100-150 ^J/cm². Alternatively, the light sources may emit a light intensity of minimum 50 7cm² or 75 7cm² and/or maximum of 180 7cm², 190 7cm² or 200 7cm². The light intensity may be determined as a total light intensity applied per day, i.e. 24 hours, distributed over the area to be treated. This allows the light sources to emit light at an intensity capable of penetrating into the body at a depth of about 1cm whilst keeping its intended effect.

In one embodiment, at least one of the pulse frequency, the pulse duty-cycle, the wavelength and the light intensity is tuned to target a predetermined bacterial group.

The characteristics of the pulsed light may be tuned to target a specific bacteria where the pulsed light may penetrate the tissue and kill bacteria hiding behind other bacteria, human cells or other obstacles. The pulse profile may be tuned to match the ROS time for a specific bacteria to reduce the non-effective light. This enables the first light to kill as many bacteria cells as possible during treatment. This is particularly relevant for the treatment of chronic wounds.

In one embodiment, a temperature of the wound is measured during use by a temperature sensing unit, e.g. a thermal camera, and transmitted to the control unit.

The device may measure the temperature of the wound during treatment to prevent overheating of the tissue. If too much thermal energy is introduced, a hot spot may occur resulting in increased pain. A threshold may used to detect if the temperature exceeds the safety limit. If the temperature exceeds the safety limit, then the control unit may turn the light source off. If the temperature is below the safety limit, then the treatment may continue. This may be particularly relevant for peripheral neuropathy, where there is a loss of protective sensation, and the patient can therefore not feel the heat.

Thus, according to any embodiment of the first aspect, the device may comprise a thermal camera configured to monitor the temperature of the light receiving surface being the surface to be treated.

In one embodiment, at least one camera captures at least one type of image data of the wound which is transmitted to the control unit, wherein the control unit determines the presence of a bacteria and/or a blood flow of the wound based on the captured image data.

As mentioned earlier, different types of cameras may be arranged in the end effector. The image data from the cameras may be analysed by the processor in the control unit, which may determine one or more parameters relating to the conditions of the wound. In particularly, an increase in the measured fluorescent level may indicate the presence of a bacterial infection. The image, preferably a colour image, of the wound may be captured by a colour camera and used to identify areas of interest. For example, but not limited to, the colour camera may be a hyperspectral camera configured to capture a number of spectral images within a number of spectral bands, said number of spectral images and thus spectral bands being about 10, but could also be less than or greater than 10. However, the use of cameras may be combined with other sensors to provide the medical practitioner with crucial information about the wound before, during and after the treatment to ensure the optimal heating trajectory.

According to any embodiment of the first aspect, the device comprises a fluorescent camera and the control unit is configured to detect the presence of bacteria in the wound, and/or the device comprises a haemoglobin camera and the control unit is configured to determine the blood flow of the wound. The device may particularly comprise a fluorescent camera used to monitor a fluorescent level of the wound. The fluorescent camera may be connected to the control unit, which may calculate the fluorescent level based on the image data captured by the camera. The control unit may further detect an increase in the measured fluorescent level, which may indicate the presence of a bacteria and thus a bacterial infection in the wound.

The device may particularly comprise a haemoglobin camera used to monitor a haemoglobin concentration of the wound. The haemoglobin camera may be a near-infrared optical scanner (NIROS) or another near-infrared spectroscopy measuring device. The haemoglobin camera may be connected to the control unit, which may calculate the haemoglobin concentration based on the image data captured by the camera. The control unit may further determine the blood flow in the wound based on the measured haemoglobin level.

In one embodiment, a second light is further emitted onto the treatment area by the light sources, wherein the second light is centred around a wavelength of 625 nm, and/or a third light is further emitted onto the treatment area by the light sources, wherein the third light is centred around a wavelength of 850 nm.

The emission of a first light may be combined with the emission of at least one further light, e.g. a near-infrared or red light. In particular, the first light may be combined with a second light with a wavelength with a band range centred around 625 nm. Alternatively or additionally, the first light may be combined with a third light with a wavelength with a band range centred around 850 nm. This agitates the human cells to promote cell growth and thereby promote healing in the wound.

By combining the first light with the second light and/or third light, the toxicity effect of the first light is reduced, and the ATP production and blood flow is increased.

Hence, according to any embodiment of the first aspect, at least one light source emits light at a wavelength of 625 or 850 nm to increase ATP production or to increase blood flow.

Preferably, the present device or method described above is used to treat chronic wounds, preferably of a human body.

Within this context, the term "chronic wound" should be understood as a wound that fails to progress through a normal, orderly, and timely sequence of repair, or in which the repair process fails to restore anatomic and functional integrity after three months. See for example the article: "Chronic wound pathogenesis and current treatment strategies: a unifying hypothesis" by Thomas A Mustoe, et aL, published in Plastic and Reconstruction Surgery, June 2006; 117(7 suppl) : 35S-41S. Brief description of the figures

Figure 1 shows an embodiment of a device for wound treatment according to the invention, Figure 2 shows an embodiment of a front surface of an end effector of the light emitting unit according to the invention,

Figure 3 shows an embodiment of a controller/gas purifier to be used together with the light emitting device,

Figure 4 shows an exemplary light scatter graph of the light distribution of 405 nm blue light in a human dermis tissue,

Figure 5 shows an exemplary map of the energy distribution caused in the wound by the end effector,

Figure 6 shows an exemplary graph of the spectral band of the emitted blue light, and Figure 7 shows four exemplary graphs of the frequency transmission of pulsed light versus constant light.

The invention will now be described in further detail in the following.

Detailed description of the invention

Figure 1 shows an embodiment of a medical device for wound treatment according to the invention. The device is configured as a mobile, compact device. The device comprises an end effector 1 connected to a mechanical arm 3 via a connecting joint 2. The mechanical arm 3 is further connected to a trolley with wheels 6. A main box 5 comprising a control unit (no shown) is arranged on the trolley. The control unit is connected to a user terminal 4. Here, the user terminal is shown as a touchscreen.

The mechanical arm 3 allows the end effector 1 to be moved into position and orientated relative to a wound of a patient's body. The device can be operated via the user terminal 4 and the treatment process can be activated via the user terminal 4.

Figure 2 shows an embodiment of a front surface of a housing 17 of the end effector 1 of the device according to the invention. The front surface is divided into a central part and a surrounding outer part. Handles 8 are provided on the end effector 1 to enable the operator to move it into the correct position and orientation.

A plurality of cameras 9-12 is arranged within the central part. Here, a colour camera 9 is used to capture a coloured image of the wound. A thermal camera 10 is used to detect the temperature of the wound. A fluorescent camera 11 is used to detect the presence of bacteria in the wound. A haemoglobin camera 12 is used to determine the blood flow of the wound. Further, a distance sensor 13 is arranged on the front surface to measure the distance between the front surface and the wound.

A plurality of light sources 14-16 is arranged within the outer part of the front surface. First light sources 14 are adapted to emit a first light with a wavelength of 405 nm. Further, second light sources 15 are adapted to emit a second light with a wavelength of 625 nm. Further, third light sources 16 are adapted to emit a third light with a wavelength of 850 nm.

Figure 3 shows an embodiment of a control unit/gas purifier to be used together with the end effector 1. Here, a side panel of the main box is removed for illustrative purposes.

The control unit 5.3 is arranged within the main box, where electrical power is supplied to the device from a power unit 5.4. A cooling system is further arranged within the main box. Here, an air pump 5.1 and a filter system 5.2 are arranged within the main box to supply clean air to the nozzles 7 (shown in fig. 2).

Figure 4 shows an exemplary light scatter graph of the light distribution of 405 nm blue light in a human dermis tissue. Each dot represents a photon where the red/yellow/green areas indicate the depth at which bacteria are killed.

Especially 405 nm blue light is used to target and trigger a reactive oxygen species (ROS) cascade leading to the destruction of the bacteria cell membrane, killing the bacteria. Since there is no target for 405 nm light in human cells is only destroying bacteria while leaving the human cell intact. There will, however, always be light scattering in human tissue, causing heat that could result in thermal ablation of human cells. Hence, only a certain amount of light energy can be absorbed in the wound before cell damages may occur. At the same time, emitting as much light as possible around 405 nm means more dead bacteria deeper in the tissue.

A pulsed first light is thus generated by the control unit and synchronized to the bacterial ROS cascade from activation to possible reactivation for a particular bacteria group. The pulsed light causes a minimum of thermal energy to be introduced in the human tissue.

In combination with the first light having a wavelength of 405 nm, a second light with a wavelength of 625 nm and a third light with a wavelength of 850 nm light are also used to agitate the human cell in order to promote cell growth and thereby promote healing in the wound. Figure 5 shows an exemplary map of the energy distribution 19 caused in the wound by the end effector 1. The Z-axis indicated the irradiance level 9.1 per quarter centimetres. The X- axis 19.2 and the Y-axis 19.3 indicates the treatment area with its centre located at (0,0).

The layout of light sources in the front surface of the end effector may be specifically designed so that a substantially uniform energy distribution is applied to the treatment area. Hence, the respective light sources 14-16 emit light in an angle perpendicular to the wound with an averaged light intensity, where the light intensity may vary across the treatment area within a minimum threshold and a maximum threshold. This uniform energy application enables as many bacteria as possible to be killed while avoiding hot spots that might otherwise have caused thermal damage to human cells.

If the respective light sources 14-16 were to apply a parabolic energy distribution across the treatment area, then it would have a higher energy output at the centre of the treatment area.

Figure 6 shows an exemplary graph of the spectral band of the emitted first light 20. The Y- axis 20.1 indicates the amplitude of the first light 20, while the X-axis 20.5 indicates the spectral band of the first light 20.

Here, the first light 20 has a narrow band range 20.2 centred around a wavelength 20.4. The band range 20.2 is measured at a predetermined percentage 20.3 of the amplitude at the wavelength 20.4. As illustrated, as much as possible of the spectral energy is centred at the centre wavelength 20.4, which is here 405 nm. Thus allows for a higher number of bacteria to be killed.

Figure 7 shows four exemplary graphs of the frequency transmission 21 of pulsed light versus constant light. The Y-axis 21.1 indicates the amount of light energy penetrating the tissue, while the X-axis 21.2 indicates the depth of the penetration.

The first two graphs 21.3 marked "808 nm PW" shows the light energy of the pulsed light. The last two graphs 21.4 marked "808 nm CW" shows the light energy of the constant light. As illustrated, the pulsed light penetrates deeper into the human tissue compared with the constant light.

Claims

1. A device for treating wounds, preferably chronic wounds, comprising

- an end effector (1) having a front surface configured to face a wound to be treated during operation,

- at least one light source (14-16) configured to emit at least a first light with a wavelength and a light intensity that influences bacterial growth negatively,

- a control unit (5.3) connected to the end effector (1) and configured to control the operation of the at least one light source (14-16),

- wherein the front surface of the end effector (1) is configured to maintain a constant distance to the wound, and the light sources (14-16) are distributed over the front surface and orientated to emit lights onto an area to be treated, characterized in that the least one light source (14) is configured to emit the first light as a pulsed light with a predetermined pulse frequency and/or pulse duty-cycle.

2. The device according to claim 1, characterized in that the at least one light source either

- comprises a plurality of light sources (14-16) distributed or controlled to emit lights over the treated area, or

- comprises a single or a few light sources (14-16) in combination with a light distribution device, such as optical lenses, to emit lights over the treated area.

3. The device according to claims 1 or 2, characterized in that the device further comprises a cooling system configured to cool the treated area during use, preferably at least one nozzle (7) is connected to a fluid supply unit which is configured to introduce a fluid onto the treated area, and preferably the fluid is air and the nozzle is an air nozzle.

4. The device according to any one of claims 1 to 3, characterized in that the device further comprises at least one camera (11, 12) connected to a control unit (5.3) and configured to capture an image of the wound, wherein the control unit (5.3) is configured to at least determine the presence of a bacteria, a temperature of the wound, and/or a blood flow of the wound based on the captured image data.

5. The device according to claim 4, characterized in that the device comprises a fluorescent camera (11) and the control unit (5.3) is configured to detect the presence of bacteria in the wound, and/or the device comprises a haemoglobin camera (12) and the control unit (5.3) is configured to determine the blood flow of the wound.

6. The device according to any one of claims 1 to 5, characterized in that the device further comprises a distance sensor (13) connected to a control unit (5.3) and configured to measure the distance between the front surface of the end effector (1) and the wound.

7. The device according to any one of claims 1 to 6, characterized in that the end effector (1) comprises a plurality of light-emitting units, such as diodes or lamps, which light-emitting units are placed in a circular or in a polyangular pattern around a central part of the front surface of the end effector (1), and preferably the light-emitting units are divided into one or more groups that are controlled independently by the control unit (5.3).

8. The device according to claim 7, characterized in that at least one camera (10-12) is arranged within the central part of the end effector (1).

9. The device according to claim 7 or 8, characterized in that the light-emitting units are configured to emit lights over a treated area of minimum 2 cm² and/or of maximum 15 cm².

10. A method of treating wounds, comprising

- providing a device according to any one of claims 1 to 9,

- positioning the end effector (1) relative to a wound of a body,

- selecting a pulse frequency and/or pulse duty-cycle of the first light via the control unit (5.3),

- activating the light sources (14-16) and emitting at least the pulsed first light onto an area of treatment for a predetermined time period, after which the light sources (14-16) are turned off.

11. The method according to claim 10, characterized in that the first light is centred around a wavelength (20.4) of 405 nm with a narrow band range (20.2), preferably a maximum band range of 5 nm.

12. The method according to claim 10 or 11, characterized in that the lights emitted from the light sources have a substantially uniform energy distribution over the treated area, preferably at an averaged light intensity of minimum 50 ^J/_Cm² and/or of maximum 200 ^J/_cm ².

13. The method according to any one of claims 10 to 12, characterized in that at least one of the pulse frequency, the pulse duty-cycle, the wavelength and the light intensity is tuned to target a predetermined bacterial group.

14. The method according to any one of claims 10 to 13, characterized in that a temperature of the wound is measured during use by a temperature sensing unit, e.g. a thermal camera, and transmitted to the control unit (5.3).

15. The method according to any one of claims 10 to 14, characterized in that at least one camera (11-12) captures at least one type of image data of the wound which is transmitted to the control unit (5.3), wherein the control unit (5.3) determines the presence of a bacteria and/or a blood flow of the wound based on the captured image data.

16. The method according to any one of claims 10 to 15, characterized in that a second light is further emitted onto the treatment area by the light sources (15), wherein the second light is centred around a wavelength of 625 nm, and/or a third light is further emitted onto the treatment area by the light sources (16), wherein the third light is centred around a wavelength of 850 nm.