Method and apparatus for measuring the conformability of a dressing to a wound bed

Abstract

A method for measuring the conformability of a dressing (D) to a wound bed comprising: - a step of preparing a physical model (16) which simulates the irregular surface of a skin lesion, for example a skin ulcer, wherein the model defines a cavity (17), - a step of filling the cavity (17) with a liquid (L) which simulates the presence of exudate, - a step of positioning the dressing (D) on the model (16) so that the dressing (D) covers the cavity (17), - a step of detecting and processing images of the model (16) to determine a numerical value representative of the conformability.

Description

[0001] “METHOD AND APPARATUS FOR MEASURING THE CONFORMABILITY OF A DRESSING TO A WOUND BED”

[0002] FIELD OF THE INVENTION

[0003] The present invention concerns a method and an apparatus for measuring the conformability of a dressing to the bed of a skin lesion, that is, to the underlying irregular skin surface on which the dressing is to be applied.

[0004] BACKGROUND OF THE INVENTION

[0005] The advanced dressing sector is undergoing considerable growth thanks to increased life expectancy and the rise in metabolic diseases, such as diabetes and obesity.

[0006] The term “advanced dressings” indicates medical devices that can actively contribute to a wound’s healing process.

[0007] For example, these dressings are applied on skin ulcers, a type of wound that is mainly widespread in members of the elderly population, in particular, but not only, if also affected by other diseases, such as the aforementioned metabolic diseases for example.

[0008] To evaluate the effectiveness of a dressing, it is important to check the degree of conformability of the dressing to the wound, a parameter that measures the adaptability of the dressing to the wound bed.

[0009] This parameter is clinically significant because the higher the conformability, the lower the presence of air between the dressing and the wound, an area where exudate can accumulate, which increases the risk of maceration, infection and delay in healing times.

[0010] It is therefore desirable for dressings to have the highest possible conformability, so as to ideally adhere perfectly to the profile of the underlying irregular skin surface.

[0011] There is therefore the need to measure the conformability of the dressing to the wound.

[0012] The standard EN 13726:2023 (“Test method for wound dressings. Aspects of absorption, moisture vapour transmission, waterproofness and extensibility’'’') proposes a test to measure, by means of a tensile testing machine, the extensibility and permanent deformation of the material that constitutes the dressing, as parameters indicative of its ability to adapt to anatomical sites subjected to movement, such as joints for example.

[0013] Another test, developed at the Surgical Material Testing Laboratory in the United Kingdom (see the 2018 publication entitled “Wound dressing testing conformability used for hydrocolloicT by the authors Hughes, Price, Barry, Baines, Ford, Phillips) provides to fix the sample and apply increasing pressure on it until a certain height is reached. The higher the pressure needed to reach this height, the lower the conformability value.

[0014] A variant implementation of this test instead provides to apply a fixed pressure equal to 40 mmHg and to measure the height reached by the sample (see the 2011 publication entitled “An investigation into the conformability of wound dressing’'' by the authors Butcher and Waring).

[0015] A disadvantage of the tests described above is evaluating the conformability in experimental conditions far removed from those of the dressing’s real use. In particular, these tests are performed in the absence of exudate, which is instead normally present in the wound bed, and they are configured to evaluate anatomical conformability to moving parts, such as joints for example, rather than conformability to the lesion bed of a wound.

[0016] Other methods for assessing conformability are also known, such as for example the tissue conformability model described in 2005 in the publication entitled ''Antimicrobial activity of silver-containing dressings is influenced by dressing conformability with a wound surface” by Jones, Bowler and Walker in “Wounds: a compendium of clinical research and practice”’, 17(9):263-270. This method tries to reproduce the clinical conditions of use, for example by simulating the presence of exudate, but it has the disadvantage of yielding a qualitative result, whereby it is difficult to compare the conformability of different dressings, and of being poorly reproducible since the test results are highly influenced by the starting porcine substrate, which changes on each occasion.

[0017] Another solution known in the art is described in the October 2021 publication entitled “Three-dimensional shape-conformation performances of wound dressings tested in a robotic sacral pressure ulcer phantom”, by the authors Lustig and Gefen in the International Wound Journal; 18(5):670-680. This solution provides to apply a dressing to be tested on an exuding sacral ulcer model. The dressing is then removed and placed on a shape that reproduces the shape of the simulated lesion. A 3D laser scan is then performed, and the shape of the dressing is reconstructed using measurement software, calculating the contact surface between the lesion and the dressing.

[0018] A disadvantage of this solution is that some types of dressing expand considerably after removal from the simulated lesion, therefore the subsequent 3D laser scan determines a shape of the dressing that is not faithful to the one that the dressing had taken on site.

[0019] The fact that this solution provides to manipulate the dressing before reconstructing its shape, and only subsequently to process the numerical results, entails the disadvantage that the conformability measurement could be imprecise and inaccurate.

[0020] There is therefore the need to develop a method and an apparatus for measuring the conformability of a dressing, in particular an advanced dressing, to a bed of a skin lesion, which can overcome at least one of the disadvantages of the state of the art.

[0021] To do this, it is necessary to resolve the technical problem of quantifying the conformability of a dressing to the irregular surface of a skin lesion, for example a skin ulcer, under experimental conditions that reproduce the conditions of clinical use as closely as possible.

[0022] In particular, one purpose of the present invention is to develop an apparatus and to perfect a method capable of measuring the conformability of a dressing in a precise and accurate manner.

[0023] Another purpose of the present invention is to develop an apparatus and to perfect a method for continuously measuring the conformability of a dressing, which allow to display the trend of the conformability in real time while the test is being carried out.

[0024] Another purpose of the present invention is to develop an apparatus and to perfect a method for measuring the conformability of a dressing without the need to remove the dressing from the wound bed.

[0025] Another purpose of the present invention is to perfect a method for measuring the conformability of a dressing that is economical to implement, simple to carry out and effective in its results. The Applicant has devised, tested and embodied the present invention to overcome the shortcomings of the state of the art and to obtain these and other purposes and advantages.

[0026] SUMMARY OF THE INVENTION

[0027] The present invention is set forth and characterized in the independent claims. The dependent claims describe other characteristics of the present invention or variants to the main inventive idea.

[0028] In accordance with the above purposes and to resolve the technical problem described above in a new and original way, also achieving considerable advantages compared to the state of the prior art, some embodiments described here concern a method for measuring the conformability of a dressing to a wound bed.

[0029] According to one aspect of the present invention, the method comprises:

[0030] - a step of preparing a physical model which simulates the irregular surface of a skin lesion, for example a skin ulcer, and which comprises a cavity,

[0031] - a step of filling the cavity with a liquid which simulates the presence of exudate,

[0032] - a step of positioning the dressing on the model so that the dressing covers the cavity.

[0033] According to one aspect of the present invention, the method also comprises the following steps, implemented by a programmable control unit’s processor:

[0034] - a step of detecting, by means of a plurality of optical detection devices connected to the control unit, a plurality of images of the model, recorded for a certain test time period,

[0035] - a step of processing the plurality of images, which comprises a comparison step, in which the plurality of images detected during the test time period are compared, one at a time, by means of background subtraction algorithms, with those detected at the beginning of the test time period by each optical device, thus determining a numerical value representative of the conformability.

[0036] According to one aspect of the present invention, the step of preparing the physical model provides to create the model with a transparent material, for example plexiglass, epoxy resin or glass, or by using transparent material additive printing techniques, for example filament or resin 3D printers.

[0037] According to one aspect of the present invention, the step of filling the cavity provides to introduce into the cavity a certain volume of colored liquid having a color such as to define a chromatic contrast with the dressing’ color.

[0038] According to one aspect of the present invention, the processing step provides to determine the numerical value by means of the following formula:

[0039] Conformability (%) = (N° / N) x 100 where N is the number of initial pixels of the detected images, N° is the number of modified pixels of the image subsequently detected during the test time period.

[0040] According to one aspect of the present invention, the positioning step provides to place the dressing and the physical model in a seating created in a test bench of a support structure which is provided with a plurality of support elements and upper arms, wherein a respective one of the optical detection devices can be attached to each of the support elements and upper arms.

[0041] According to one aspect of the present invention, it is provided to dispose one or more optical detection devices below the test bench, on the support elements, oriented in such a way as to frame the model, and to dispose one or more optical detection devices above the test bench, on the upper arms, oriented in such a way as to frame the dressing.

[0042] According to one aspect of the present invention, the method comprises a step of illuminating by means of one or more light sources disposed, with respect to the optical detection devices, in appropriate positions such as to avoid the formation of shadow areas.

[0043] According to one aspect of the present invention, an apparatus is provided for measuring the conformability of a dressing to a wound bed comprising a seating configured to receive both a model which simulates the irregular surface of a skin lesion and is equipped with a cavity able to be filled with a liquid which simulates the presence of exudate, and also a dressing positioned on the model in such a way as to cover the cavity.

[0044] According to one aspect of the present invention, the apparatus comprises a plurality of optical detection devices for detecting a plurality of images of the model for a certain test time period, and one or more control units to which the plurality of optical detection devices is connected and comprising a processor to compare the plurality of images detected subsequently with those detected at the beginning of the test time period by means of background subtraction algorithms, thus determining a numerical value representative of the conformability. According to one aspect of the present invention, the physical model is made with a transparent material, and the liquid is a colored liquid having a color such as to define a chromatic contrast with the dressing under examination.

[0045] According to one aspect of the present invention, the apparatus comprises a support structure consisting of a test bench in which the seating is created, wherein the support structure is provided with a plurality of support elements disposed below the test bench to support it, and with upper arms which project from the test bench on the opposite side with respect to the support elements, a respective one of the optical detection devices being attached to each of the support elements and upper arms.

[0046] Some embodiments described here also concern a computer program containing instructions configured to be executed on an electronic medium so as to determine the execution of the detection step and the processing step.

[0047] One of the advantages of the method and apparatus according to the present invention is that of returning a numerical value that represents the conformability of a dressing to a lesion in a clear, direct and unequivocal manner. This helps users, who can immediately compare the conformability of different dressings.

[0048] Thanks to the numerical quantification of this parameter, dressing manufacturers could indicate it on the product’s technical data sheets, and buyers could evaluate it, together with other requirements, before proceeding with any purchase. For example, hospitals, or local health authorities, and large consumers of these advanced dressings could include, among the requirements of any tender specifications, a minimum conformability value for a dressing, since this would be a numerical value quantified in an objective manner.

[0049] Another advantage of the method and apparatus according to the present invention is that of allowing for an analysis of the dressing’s behavior in real time, during the entire test time period.

[0050] Another advantage of the method and apparatus according to the present invention is that of simulating, with a high degree of fidelity, the clinical conditions of use of the dressings through a method that is not complex from a computational point of view, and a simple and economical apparatus.

[0051] Another advantage of the method and apparatus according to the present invention is that of calculating the conformability value while the dressing remains disposed on the lesion model, and not after it has been removed, as instead happens in some solutions known in the art. This is advantageous because it prevents manipulating the dressing and the model, and therefore the calculation of the conformability is more precise and reliable, in the absence of possible alterations caused by the manipulation that occurred.

[0052] DESCRIPTION OF THE DRAWINGS

[0053] These and other aspects, characteristics and advantages of the present invention will become apparent from the following description of some embodiments, given as a non-restrictive example with reference to the attached drawings wherein:

[0054] - fig. 1 is a section, schematic and enlarged scale view of an advanced dressing applied on a wound bed, in this case a skin ulcer;

[0055] - fig. 2 is a schematic front view of an apparatus for measuring the conformability of a dressing to a wound bed;

[0056] - fig. 3 is a schematic, top plan view of the measuring apparatus of fig. 2;

[0057] - figs. 4a and 5a are three-dimensional, enlarged scale views of an enlarged detail of the apparatus in a test phase to measure the conformability of two different dressings;

[0058] - figs. 4b and 5b are images processed by the apparatus of fig. 2, which show the outcome of the tests carried out to measure the conformability of the dressings of fig. 4a and 5a, respectively;

[0059] - figs. 4c and 5c are graphs showing the percentage of white pixels present in figs. 4b and 5b, respectively, as a function of time.

[0060] We must clarify that the phraseology and terminology used in the present description, as well as the figures in the attached drawings also in relation as to how described, have the sole function of better illustrating and explaining the present invention, their purpose being to provide a non-limiting example of the invention itself, since the scope of protection is defined by the claims.

[0061] To facilitate comprehension, the same reference numbers have been used, where possible, to identify identical common elements in the drawings. It is understood that elements and characteristics of one embodiment can be conveniently combined or incorporated into other embodiments without further clarifications.

[0062] DESCRIPTION OF SOME EMBODIMENTS

[0063] With reference to figs. 2 and 3, the following is a description of an apparatus 10 for measuring the conformability of a dressing to a wound bed.

[0064] Before describing the apparatus 10, for a better understanding of the context in which the present invention has been developed we will briefly describe, with reference to fig. 1, the scope of reference from which the technical problem resolved by the apparatus 10 and by the corresponding method for measuring conformability is evident.

[0065] Fig. 1 shows a skin portion 100 which shows the skin structure, in particular its outermost epithelial layer characterized in turn by a layered structure.

[0066] A dressing D is applied to the skin portion 100. The dressing D can be an advanced dressing based on polyurethane foam, alginate, cellulose derivatives, polyacrylates, etc., in the presence or absence of an antimicrobial or antiinflammatory agent.

[0067] The skin portion 100 comprises a lesion 101, for example a skin ulcer.

[0068] The dressing D is applied to the skin portion 100 in correspondence with the lesion 101.

[0069] As can be seen in fig. 1 , the dressing D substantially follows the profile of the skin portion 100; however, there remain zones 102 in which the dressing D does not adhere perfectly to the underlying skin surface.

[0070] The extension of these zones 102 is inversely proportional to the conformability of the dressing D: the more extensive these zones 102 are, the less the dressing D has conformed to the wound bed, and vice versa. In an ideal condition, in which these zones 102 are absent, there is 100% total conformability between the dressing and the lesion.

[0071] Since the irregularities of the lesion bottom can also be extremely small, in the technical field of reference we can also speak of micro-conformability. In the present description, the term “conformability” also includes the meaning of “micro-conformability”, which is considered synonymous.

[0072] The apparatus 10 comprises a support structure 11 comprising a test bench 12 supported by a plurality of support elements 13.

[0073] In the example shown, four support elements 13 are provided, disposed at 90° with respect to each other.

[0074] The support structure 11 can also comprise one or more upper arms 14, for example two opposing arms, which project from the test bench 12 on the opposite side with respect to the support elements 13, that is, upward.

[0075] The test bench 12 comprises a seating 15 configured to receive both a model 16 that simulates the surface of a skin lesion, and also a dressing D to be tested.

[0076] The model 16 is made of transparent material. For example, it can be made using a filament 3D printer, or a resin 3D printer, or using traditional techniques with transparent materials such as plexiglass, epoxy or glass.

[0077] The model 16 defines one or more cavities 17 configured to contain a liquid L, which simulates the presence of exudate.

[0078] Preferably, the liquid L is a colored liquid, or in any case a liquid with a color such as to define a sharp chromatic contrast with the dressing D.

[0079] In one embodiment, not shown, the support structure 11 can be configured as a monolithic structure, for example shaped as a square or rectangular based prism that integrates the above described components inside it, so as to provide a stable structure that minimizes unwanted vibrations.

[0080] The apparatus 10 comprises a plurality of optical detection devices 18 oriented so as to frame a portion of the model 16 in order to acquire the corresponding images. In the example shown, six optical detection devices 18 are provided.

[0081] By way of a non-limiting example, each optical detection device 18 can comprise a camera of at least 8 Mega Pixels communicating with a memory card, for example with a 64 Giga Bytes capacity.

[0082] In the example shown, four telecameras are disposed below the test bench 12, and the remaining two are disposed above the test bench 12.

[0083] Each support element 13 supports a respective optical detection device 18 disposed below the test bench 12 and each upper arm 14 supports an optical detection device 18 disposed above the test bench 12.

[0084] It is evident that the apparatus can comprise a number of optical detection devices different from six, and their arrangement may also be different from that described here as a non-limiting example.

[0085] The apparatus 10 further comprises one or more control units 20, to which all the optical detection devices 18 are connected. Preferably, each optical detection device 18 is equipped with a respective control unit 20.

[0086] Each control unit 20 comprises a processor 21, which receives the images acquired by the optical detection devices 18 and processes them in the manner that will be described below.

[0087] The processor 21 can be of a type known in the art and can be configured as a single small sized microchip with high computational performance.

[0088] A computer- implemented method for measuring the conformability of a dressing D to a wound bed is described below. The method according to the present invention can be implemented using the apparatus 10 described above.

[0089] The method provides a step of preparing a physical model 16 that simulates the irregular surface of a skin lesion, for example a skin ulcer. For this purpose, the model 16 defines a cavity 17, configured to contain a liquid L that simulates exudate.

[0090] The model 16 is made of transparent material using additive printing techniques or with other manufacturing techniques that use materials such as plexiglass, epoxy resin or glass.

[0091] The method then provides to attach the model 16 to the seating 15 of the test bench 12 in correspondence with a perimeter edge of the model. The model 16 is attached in such a way that the cavity 17 protrudes below the test bench 12, toward the support elements 13.

[0092] Subsequently, there is provided a step of filling the cavity 17, in which the liquid L is poured into the cavity. The liquid L is a colored liquid, with a color capable of defining a sharp chromatic contrast with the dressing.

[0093] The method then provides to position the dressing D on the model 16 in such a way as to cover the cavity 17. In order to do this, the dressing D is also attached to the seating 15.

[0094] Once the preparation, or set-up, step is finished, the method provides to start a certain test time period, for example equal to fifteen minutes.

[0095] The optical detection devices 18 begin detecting images of the model 16, starting from when the test time period begins.

[0096] The detected images are a sequence of frames, in the form of frames of a video shot.

[0097] For example, each optical detection device can be set to automatically detect the images of the model 16 with a frequency comprised between 1 and 30 frames per second (fps), more preferably between 1 and 10 frames per second.

[0098] Preferably, in the video processing step it is provided to apply an image that serves as a mask so as to be able to evaluate only the pixels that frame the model 16.

[0099] In the processing step, the processor 21 of each control unit 20 calculates the conformability as a percentage value, using the formula:

[0100] Conformability (%) = (N° / N) x 100 where N is the number of initial pixels of the images detected by the respective optical detection device 18 at the beginning of the test time period, and N° is the number of pixels modified during the test time period.

[0101] Each control unit 20 calculates the conformability value, by means of the formula indicated above, on the basis of the images detected by the respective optical detection device 18 to which the control unit 20 is connected.

[0102] The conformability value of the dressing D is calculated as an average of the conformability values calculated by the individual control units 20 associated with the various optical detection devices 18, therefore in the example given here as the average value of six conformability values, each calculated starting from the images detected by the respective optical detection device.

[0103] The processor 21 can also create a graph in which it is possible to display the conformability’s trend over time, wherein the conformability is expressed as a percentage value calculated according to the formula indicated above.

[0104] The graph shows the value calculated by the processor 21, by applying the aforementioned formula to each frame detected by the optical detection devices, therefore N° is the number of modified pixels of the frame considered on each occasion, and N always remains constant and equal to the number of initial pixels of the image detected at the beginning of the test time period.

[0105] The apparatus 10 can be equipped with a lighting system, not shown, comprising one or more light sources which are disposed, with respect to the optical detection devices 18, in appropriate positions such as to avoid the formation of shadow areas that could undermine the correct execution of the method, distorting the number of “white” pixels detected by the optical detection devices.

[0106] In some embodiments, the apparatus 10 can be equipped with an automatic device, comprising for example a robotic arm equipped with a gripper that can selectively grip and release the dressing D.

[0107] In some embodiments, the apparatus 10 can comprise a sensor, not shown, that can automatically initiate the frame detection. Advantageously, this sensor can be operationally and functionally connected to the robotic arm, so as to automatically start the frame detection step when the robotic arm has positioned the dressing D.

[0108] In some embodiments, the apparatus 10 can comprise a heating system, for example comprising one or more electrical resistors to heat the exudate and keep it at a desired temperature, for example equal to 37°C.

[0109] In some embodiments, the apparatus 10 can comprise an automatic device for filling the cavity 17 with the liquid. This device comprises for example a pump that, by means of one or more tubes, allows to fill the cavity 17 at a constant speed.

[0110] EXAMPLE 1 and 2

[0111] Figs. 4a, 4b and 4c show a first example of application of a method for measuring the conformability of a dressing D to a lesion 101, by means of the apparatus 10 in accordance with the teachings of the present invention.

[0112] Figs. 4a and 5a show a dressing D applied on a model 16 which comprises several conical-shaped protuberances that simulate, in a significantly emphasized manner, the irregular surface of a lesion. In this case, the volume of the cavity 17 is defined by the sum of the volumes of these protuberances, since they are contiguous and communicating with each other.

[0113] The model 16 is made of transparent material so that the colored liquid L, which is disposed inside the cavity 17, is visible from the outside. Initially, the cavity 17 is filled with a certain volume of liquid L, indicated with a dotted pattern in the drawing and suitable to almost completely fill the cavity 17.

[0114] We must clarify that figs. 4a and 5a show the model 16 at the end of the fifteen- minute test time period, since a large part of the volume of liquid L with which the cavity 17 had been filled is no longer present inside the conical protuberances.

[0115] Figs. 4b and 5b show the image reworked by the processor 21, starting from the images received by the optical detection devices 18 at the end of the fifteen-minute test time period. The “white pixels” can be observed in correspondence with those portions of conical protuberances where the colored liquid L is no longer present to chromatically contrast the dressing.

[0116] This image is the result of the processing carried out by the processor 21, which implements background subtraction algorithms, comparing the images detected in subsequent instances of the test time period with the initial image detected at the beginning of the test time period.

[0117] Figs. 4c and 5c both show a graph in which the y-axis indicates the conformability’s percentage value, calculated using the formula disclosed above, and the x-axis indicates time, expressed in seconds.

[0118] At the end of the fifteen-minute (900 seconds) test time period, the dressing D subject to the test referred to in figs. 4a-4c reaches a conformability of approximately 73%. The graph shows that this dressing D does not immediately adhere to the wound bed, since in the first 60 seconds the conformability remains practically null. From this moment, the conformability gradually increases with a rather high gradient, until it reaches a conformability of approximately 70% after about 180 seconds from the beginning of the test time, and then stabilizes around this value.

[0119] At the end of the fifteen-minute (900 seconds) test time period, the dressing D subject to the test referred to in figs. 5a-5c reaches a conformability of approximately 25%. The graph shows that this dressing D tends to adhere to the wound bed immediately, since the conformability already reaches the aforementioned value within the first 30 seconds. From this point on, the conformability stabilizes and remains approximately constant throughout the entire test time period.

[0120] Comparing the two dressings tested, the apparatus 10 and method according to the present invention reveal that the first dressing has a much higher conformability, with a ratio of about 3:1, compared to that of the second dressing, albeit with a different behavior during the test time period.

[0121] The apparatus and method according to the present invention exploit image processing techniques based on the modification of the pixels as a function of the absorption of the liquid by the dressing being tested. In practice, the higher the absorption of the liquid L by the dressing D, the higher the latter’s conformability. In fact, the liquid L is absorbed in the presence of adhesion between the dressing D and the wound bed. In this case, “white pixels” will be found where the liquid is no longer present within the cavity 17. In contrast, where there are zones similar to the zones 102 of fig. 1 , in which the dressing D does not adhere to the profile of the surface of the wound bed, the fluid L stagnates in the cavity 17 and - in the absence of contact through adhesion - it cannot be absorbed by the dressing D. In this case, the pixels will not turn white, but will remain dark due to the colored liquid L still present inside the cavity.

[0122] It is clear that modifications and / or additions of parts or steps may be made to the apparatus and method as described heretofore, without thereby departing from the field and scope of the present invention, as defined by the claims.

[0123] It is also clear that, although the present invention has been described with reference to some specific examples, a person of skill in the art will be able to achieve other equivalent forms of an apparatus and method for measuring the conformability of a dressing to a skin lesion, having the characteristics as set forth in the claims and hence all coming within the field of protection defined thereby.

[0124] In the following claims, the sole purpose of the references in brackets is to facilitate their reading and they must not be considered as restrictive factors with regard to the field of protection defined by the claims.

Claims

CLAIMS1. Method for measuring the conformability of a dressing (D) to a wound bed, comprising:- a step of preparing a physical model (16) which simulates the irregular surface of a skin lesion, for example a skin ulcer, wherein said model comprises a cavity (17),- a step of filling said cavity (17) with a liquid (L) which simulates the presence of exudate,- a step of positioning said dressing (D) on said model (16) so that the dressing (D) covers said cavity (17), characterized in that it also comprises the following steps, implemented by a processor (21) of a programmable control unit (20):- a step of detecting, by means of a plurality of optical detection devices (18) connected to said control unit (20), a plurality of images of said physical model (16) for a certain test time period,- a step of processing said plurality of images, which comprises a comparison step, in which the plurality of images detected during the test time period are compared, one at a time, by means of background subtraction algorithms, with those detected at the beginning of said test time period by each of said optical detection devices (18), thus determining a numerical value representative of said conform ability.

2. Method as in claim 1, characterized in that said plurality of images is a sequence of frames, in the form of frames of a video shot.

3. Method as in claim 1 or 2, characterized in that each optical detection device can be set to automatically detect said plurality of images with a frequency comprised between 1 and 30 frames per second (fps), more preferably between 1 and 10 frames per second (fps).

4. Method as in any claim hereinbefore, characterized in that in said processing step it is provided to apply an image that serves as a mask so as to be able to evaluate only the pixels that frame said physical model (16).

5. Method as in any claim hereinbefore, characterized in that said step of preparing said physical model (16) provides to create the model with a transparent material, for example plexiglass, epoxy resin or glass, or by using transparent material additive printing techniques, for example with filament or resin 3D printers.

6. Method as in any claim hereinbefore, characterized in that said step of filling said cavity (17) provides to introduce into said cavity (17) a certain volume of colored liquid (L), having a color such as to define a chromatic contrast with the dressing (D) to be analyzed.

7. Method as in claim 6, characterized in that said filling step provides to fill said cavity (17) by means of an automatic filling system.

8. Method as in any claim hereinbefore, characterized in that said processing step provides to determine said numerical value by means of the following formula:Conformability (%) = (N° / N) x 100 where N is the number of initial pixels of the detected images, N° is the number of modified pixels of the image subsequently detected during said test time period.

9. Method as in any claim hereinbefore, characterized in that said positioning step provides to place said dressing (D) and said physical model (16) in a seating (15) created in a test bench (12) of a support structure (11) which is provided with a plurality of support elements (13) and upper arms (14), wherein a respective one of said optical detection devices (18) is attached to each of said support elements (13) and upper arms (14).

10. Method as in claim 9, characterized in that said positioning step can be carried out by means of an automatic device, comprising a robotic arm equipped with a gripper which can selectively grip and release said dressing (D).

11. Method as in claim 9 or 10, characterized in that it is provided to dispose one or more optical detection devices (18) below said test bench (12), on said support elements (13), oriented in such a way as to frame said model (16), and in that it is provided to dispose one or more optical detection devices (18) above said test bench (12), on said upper arms (14), oriented in such a way as to frame said dressing (D).

12. Method as in any claim hereinbefore, characterized in that it comprises a step of illuminating by means of one or more light sources disposed, with respect to the optical detection devices (18), in appropriate positions such as to avoid the formation of shadow areas.

13. Apparatus (10) for measuring the conformability of a dressing (D) to a wound bed comprising a seating (15) configured to receive both a model (16) whichsimulates the irregular surface of a skin lesion and is equipped with a cavity (17) able to be filled with a liquid (L) which simulates the presence of exudate, and also a dressing (D) positioned on said model (16) in such a way as to cover said cavity(17), characterized in that it comprises a plurality of optical detection devices(18) for detecting a plurality of images of said model (16) for a certain test time period, and one or more control units (20) to which said plurality of optical detection devices (18) is connected and comprising a processor (12) to compare said plurality of subsequently detected images with the images detected at the beginning of said test time period by means of background subtraction algorithms, thus determining a numerical value representative of said conformability.

14. Apparatus as in claim 13, characterized in that said physical model (16) is made with a transparent material and said liquid (L) is a colored liquid having a color such as to define a chromatic contrast with the color of the dressing (D).

15. Apparatus as in claim 13 or 14, characterized in that it comprises a support structure (1 1) comprising a test bench (12) in which said seating (15) is created, wherein said support structure (11) is provided with a plurality of support elements (13) disposed below said test bench (12) to support it and with upper arms (14) which project from said test bench (12) on the opposite side with respect to said support elements (13), a respective one of said optical detection devices ( 18) being attached to each of said support elements (13) and of said upper arms (14).

16. Computer program containing instructions configured to be executed on an electronic medium so as to determine the execution of said detection step and said processing step.

Images