GB2624657A

GB2624657A - Method of limb scanning

Info

Publication number: GB2624657A
Application number: GB2217565.7A
Authority: GB
Inventors: Nygren David; John Rawson Neill; Lawson Smith Damian; Dagevos Van Rij Johannes; Webster Iain
Original assignee: Smith and Nephew PLC; TJ Smith and Nephew Ltd
Current assignee: Smith and Nephew PLC; TJ Smith and Nephew Ltd
Priority date: 2022-11-24
Filing date: 2022-11-24
Publication date: 2024-05-29
Also published as: GB202217565D0

Abstract

A method of obtaining 3D geometric data of a body part comprises providing an elastic item 32, wherein least a portion of the elastic item comprises a pattern visible on the outer surface thereof, wherein the pattern has a predictable deformation on elongation. The method comprises applying the elastic item 32 about a body part 34 such that the elastic item 32 is elongated in at least one dimension and acquiring images of the elastic item when applied to the body part 36, wherein the images are acquired from a plurality of different orientations and/or positions. The method comprise processing said images to obtain 3D geometric data relating to the shape of the body part 38. An elastic sleeve 10 for obtaining 3D geometric data of a body part is provided. At least a portion of the elastic sleeve 10 comprises a pattern visible 12 on the outer surface thereof. On elongation in at least two dimensions, the pattern 12 deforms in a predictable and known manner.

Description

Method of limb scanning

BACKGROUND Field

[01]Embodiments of the present disclosure relate to methods for obtaining 3D images and models of the human or animal body and apparatus for use therein.

Description of the Related Art

[02]Compression garments are worn on a person's or patient's body part and apply pressure to the body part to improve blood circulation therein. This can help to improve or cure a number of different health conditions. Compression garments may be commonly worn on limbs, for example on the leg and/or foot. Compression garments worn on the leg and/or foot may be termed compression stockings or compression socks.

[03]Compression bandages are known for use in the treatment of oedema and other venous and lymphatic disorders, e.g., of the lower limbs. An area where compression bandages are considered particularly useful is in the management and treatment of chronic wounds, such as venous leg ulcers. Achieving optimum pressure when applying compression to (e.g. leg) ulcer patients creates challenges for the clinician. Traditionally a skilled healthcare worker must select and fit the most appropriate bandage for the patient in need thereof It is important that the compression garment provided to the patient is configured to accurately apply a clinically predetermined pressure. If the pressure which is applied is too great, then this can cause pain or discomfort. If the pressure is too little, then the patient's blood circulation may not be improved.

[04]Selecting the correct bandage may require manual measurement with a tape measure or device or scanning body parts with advanced 3D camera systems. Recent developments in scanning technology and bandage production have allowed personalised bandages to be created, and these can assist with accurately applying the predetermined pressure.

[05]However, manual measurements are often not sufficiently accurate and to create a sufficiently accurate 3D image/model of the body shape/limb to provide measurements and volumes typically requires dedicated or expensive advanced 3D optical systems.

[06] It is therefore desirable to be able to obtain accurate 3D images and models without the need for dedicated or expensive advanced 3D optical systems.

DETAILED DESCRIPTION

[07]Embodiments relate to methods of obtaining 3D images of the human or animal body and apparatus for use therein. Also described are various articles, some of which are intermediate articles of the methods described herein. Such articles include elastic sleeves for use in the methods.

[08]According to the first embodiment of the invention is provided a method of obtaining 3D geometric data of a body part comprising (i) providing an elastic item at least a portion of which comprises a pattern visible on the outer surface thereof wherein the pattern has a predictable deformation on elongation (ii) applying the elastic item about a body part such that the elastic item is elongated in at least one dimension (iii) acquiring images of the elastic item when applied to the body part wherein the images are acquired from a plurality of different orientations and/or positions (iv) processing said images to obtain 3D geometric data relating to the shape of the body part disclosed herein.

[09] The elastic item may have any suitable form for application to a body part. The elastic item may be an elastic bandage or sleeve. In preferred embodiments the elastic item is an elastic sleeve. By elastic sleeve is meant a tubular structure that is typically elasticated in more than one dimension. The elastic item will be appropriately sized to be in tension when applied to the relevant body part.

[10]Preferably the elastic item has a predictable deformation on elongation in at least two dimensions.

[11]The method may comprise the further step of using the 3D geometric data to select or generate a garment shaped to fit said body part. The method may be used to generate a knitting pattern for a garment shaped to fit said body part. Such methods are known in the art for example in EP1756343.

[12] Preferably the garment is a compression garment for a patient in need thereof, preferably a custom produced compression garment, more preferably a custom produced knitted compression garment. By using the 3D geometric data, a garment may be produced which uses the exact measurements of the body part including where the body part does not have a uniform cross section. This is advantageous as typically measurements have assumed a uniform, typically circular cross section which does not allow for asymmetry or the application of higher pressure to specific areas of a body part in need thereof in the case of compression bandages. This may also be of particular use in fitting other garments such as fashion garments where body parts are not uniform and a good fit depends on the 3D shape of the body part rather than just the cross-sectional measurements.

[13]The images may be individual still images or a continuously acquired image in the form of a video. The images may be acquired by any suitable means. However, preferably the images are acquired by a handheld device such as a conventional digital camera, smartphone, tablet or other commercially available handheld device. This enables the method to be carried out without specialist or expensive imaging equipment. Such devices are generally more user friendly and are lightweight and easy and familiar to manoeuvre. The devices may also be easily manoeuvred into positions that a larger or fixed piece of imaging equipment may not be suitable for. Preferably the device is a smart phone or tablet. Alternatively, or in addition, the imaging device may operate about a fixed axis or the imaging device may be fixed and the body part to be imaged may be rotated or moved in an appropriate manner relative to the imaging device.

[14] Processing the images may comprise the step of comparing the acquired images with the undeformed pattern and/or known deformations of said pattern.

[15] The pattern may be a continuous pattern or may be a series of figures forming an overall repeating pattern. The figure or figures of the pattern may be of any shape including for example squares or circles. In some examples, the figures of the pattern may be deformable, whilst in other examples, the figures of the pattern may be non-deformable. The pattern may provide a visual indication of the varying amounts and the direction of elongation. When the elastic item is stretched, the shape or contours of the figures or the continuous pattern and/or their position relative to each other may be altered. In examples wherein the figures are non-deformable, the shape and size of the figures may remain the same whilst the space between the figures may be altered when the elastic item is deformed.

[16]The change in shape and/or position of the pattern or the figures comprising the pattern may be an indication of the amount the item is elongated and in which direction. Comparing the images may comprise comparing a shape and/or position of the pattern or figures comprising the pattern with a shape and/or position of the pattern or figures comprising the undeformed pattern and/or the known deformations of the pattern.

[17] For example, processing the images may comprise determining a size of a figure in the pattern or a distance between figures in the pattern and comparing the determined size or distance with a corresponding size or distance in the undeformed pattern and/or the known deformations of the pattern.

[18]1n determining the size of the figure or distance between the figures, a reference marker may be used, wherein the reference marker has known dimensions and is present in the image. The reference marker may be attachable to the elastic item. For example, the reference marker may be adhesive, such as a sticker or adhesive disc, which may be attachable to the elastic item. In examples in which the figures are non-deformable, the figures, having known dimensions, may form reference markers for determining the distance between figures.

[19]Data including the undeformed pattern and/or known deformations of said pattern may be provided with the elastic item or be available from another source, for example online or in an associated computer program. A computer readable code may be provided with or on the elastic item that enables the user to obtain such data. For example, a QR code may be provided with the elastic item that enables the user to download the relevant data to the program used to process the images. The program may be an application suitable for use on a smartphone or tablet. Alternatively, the processing may be carried out on a separate device or on a cloud service.

[20]The device used to acquire the images or the computer program which processes them may provide feedback to the user as to whether the images are suitable and sufficient to produce 3D geometric data. The user may receive audio or visual feedback that sufficient images or images covering a sufficient proportion of the elastic item have been obtained for accurate 3D geometric data to be produced from the images. Hence, according to a further embodiment of the invention are provided computer-implemented methods of obtaining 3D geometric data of a body part. In preferred embodiments, such methods utilise a smartphone or tablet. The smartphone or tablet is typically used at least for the purpose of acquiring images of an elongated elastic item applied to a three-dimensional member) to the computer program. The processor of the smartphone or tablet may also be used to analyse the image data to determine elongation. However, alternatively or in addition, analysing the image data may occur on a remote server. Regardless of whether a smartphone or tablet or remote server is conducting the analysis, the method generally comprises receiving image data that includes a digital image of an elongated elastic item, analysing the image data to determine elongation of the elastic item by comparing features of the elongated pattern to model features that define a predetermined elongation state or non-elongated state, and producing 3D geometric data relating to the body part disclosed herein.

[21]During analysis the features of the elongated item in the plurality of images are typically compared to model features that define a predetermined elongation state. The term "feature" refers to any distinct element or the overall appearance of the pattern. The predetermined elongation state of the pattern may be the non-elongated state of the pattern. However, the predetermined elongation state of the pattern can be any known elongation state.

[22] In one embodiment, the predetermined elongation state is preloaded and stored in the computer program of the smartphone or tablet or remote server. The computer program computes the difference between the elongated and predetermined elongation state.

[23]The digital images of the elongated elastic item preferably show substantially the entire outer surface of the body part.

[24] The method generally comprises receiving image data that includes digital images of an elongated pattern on an elastic item, analysing the image data to determine elongation of the elastic item by comparing features of the elongated pattern to model features that define a predetermined elongation state, utilising the determined elongation of the elastic item to determine the 3D geometry of the body pad and providing 3D geometric data associated with the body part as an output.

[25] Various elements and methods described herein may be implemented through the execution of machine-readable instructions by a processor. The processing system may comprise a processor in association with a non-transitory machine-readable storage medium. The machine-readable storage medium may be a tangible storage medium, such as a removable storage unit or a hard disk installed in a hard disk drive. The machine-readable storage medium comprises instructions to implement step (iv) of the first embodiment of the invention.

[26] In some embodiments, the methods described herein may use a computer readable code for the purpose of accessing information associated with the elastic item such as the predetermined (e.g. non-elongated and/or known elongation states of the pattern) elongation state of the pattern. The computer readable code may be present on the elastic item itself or a package thereof.

[27]Any suitable computer readable code may be used. The code may be a one-dimensional code, such as a bar codes. Alternatively, the code may be a two-dimensional code such as a OR code.

[25] Many of today's mobile phones or tablet computers with a built-in camera include software allowing the reading of bar codes and OR codes.

[29]According to a second aspect of the invention is provided an elastic sleeve for obtaining 3D geometric data of a body part wherein at least a portion of the elastic sleeve comprises a pattern visible on the outer surface thereof wherein, on elongation in at least two dimensions, the pattern deforms in a predictable and known manner.

[30]The elastic item or sleeve suitable for use in the methods of the first aspect of the invention may be made of any suitable elasticated material. Preferably the elastic item or sleeve comprises polyamide, polyester etc. Preferably the fabric of the elastic item or sleeve has a denier of between 20 and 150, more preferably between 40 and 100. The material also typically comprises an elastic fibre such as Lycra®.

[31]Elastic materials are materials that possess high elongations (10%-800%) prior to breaking and that recover fully and rapidly from high elongations up to their breaking point. The elastic material may comprise any suitable elastic material. Suitable elastic materials include crosslinked natural and synthetic rubbers, spandex (segmented polyurethanes), and anidex (crosslinked polyacrylates). Preferably the elastic material is spandex.

[32] The degree of elasticity of the elastic item or sleeve may be such that the elastic item or sleeve conforms to the shape of the body part that it is applied to but not too great such that the tension in the elastic item or sleeve significantly deforms the shape of the body part when applied.

[33] The methods described herein utilise an elastic item comprising a pattern visible on the outer surface thereof wherein the pattern has a predictable deformation on elongation. Typically the pattern may be applied to the outer surface in use of the elastic item. Preferably the pattern has a predictable deformation on elongation in at least two dimensions, more preferably at least three dimensions. The pattern may be a regular pattern. The pattern may be a continuous pattern or may be a series of figures forming an overall repeating pattern. The figure or figures of the pattern may be of any shape including for example squares or circles. The pattern provides a visual indication of the varying amounts and the direction of elongation. When the elastic item is stretched, the shape or contours of the figures or the continuous pattern and/or their position relative to each other are altered. The change in shape and/or position of the pattern or the figures comprising the pattern is an indication of the amount the item is elongated and in which direction. Preferably the pattern covers at least 50% of the surface of the elastic item, more preferably at least 60%, at least 70%, at least 80% or at least 90%. Preferably the pattern covers substantially the entire surface of the elastic item.

[34]The repeat interval of the pattern is typically no greater than about 5 cm, 4 cm, 3 cm, 2 cm, 1 cm or 0.5 cm. The repeat interval of the repeating pattern may be dependent on the size of the body part to which it is intended to be applied and typically is no greater than about a quarter of the smallest circumference of the body part it is intended to be applied. Typically, no greater than about a sixth, an eighth a tenth or a twelfth of the smallest circumference of the body part.

[35] The size of the figures of the pattern can be any suitable size. Typically the figures have a dimension of between 1 and 5 mm, preferably between 1 and 3 mm.

[36] The pattern may comprise a reference point from which the elongation can be gauged. The reference point may be a fixed button or a may have a different appearance to the rest of the pattern such as a different coloured element of the pattern.

[37] The pattern may be applied in any suitable way or may be incorporated into the material of the elastic item on production. Preferably the pattern is printed onto the material of the elastic item by any suitable means. Preferably the pattern is formed or printed in a colour that has sufficient contrast to the unpatterned portion of the elastic item such that the pattern may be easily determined in the images of the applied item.

[38] In use, the elastic item is in tension when applied to the body part in at least one direction. Preferably the elastic item is in tension in at least two directions. When the elastic item is in tension in all directions a more accurate 3D representation of the body part can be determined.

[39]According to a third embodiment is provided a computer program comprising instructions to execute step (iv) of the method of the first embodiment.

[40]Preferably step (iv) comprises the steps of receiving image data that includes digital images of the elastic item when applied to the body part.

[41]According to a further embodiment is provided a computer-readable medium having stored thereon the computer program of the third embodiment.

BRIEF DESCRIPTION OF THE DRAWINGS

[42] Embodiments of the present disclosure will now be described hereinafter, by way of example only, with reference to the accompanying drawings in which: [43] FIG. 1 illustrates an elastic sleeve according to an embodiment of the invention; [44] FIG. 2 illustrates the elastic sleeve of Figure 1 in use when applied to the lower half of a patient's leg; [45] FIG. 3 illustrates an elastic sleeve according to another example; [46] FIG. 4 illustrates the elastic sleeve of figure 3 in use when applied to the lower half of a patient's leg; [47] Figure 5 illustrates an example method; [48] FIG.6 illustrates a processing system comprising a processor in association with a non-transitory machine-readable storage medium.

[49]The elastic sleeve 10 of Figure 1 may be formed of any suitable material having the required elasticity. The elastic sleeve 10 has a pattern of figures, wherein the figures are 1mm diameter circular dots 12 applied at an interval of lOmm applied to the outer surface thereof although any suitable size or shape of repeated figures may be applied and at any suitable interval. The pattern is printed onto the outer surface of the elastic sleeve 10 although any suitable method may be used and the pattern may be alternatively integrated into the material of the sleeve or applied to the reverse side provided the pattern is visible on the outer surface of the sleeve in use. A reference dot 14 which is a different colour to the remaining dots 12 is located at a particular point on the sleeve 10.

[50]1n use the sleeve 10 is applied to the body part of interest. In this instance the lower portion of the leg as illustrated in Figure 2. On application, the elastic sleeve 10 is elongated in at least two dimensions and as such the pattern is deformed. As shown in figure 2, the circular dots 12 are non-deformable, such that when the elastic sleeve is elongated, the size and shape of the circular dots 12 remains the same but the distance between the dots 12 changes.

[51] Images of the sleeve in use are obtained by a suitable device, typically a smartphone or tablet. Sufficient images are acquired to be able to recreate the entire surface of the elastic sleeve. The images are processed and compared to both the unelongated pattern and known elongations and deformations of the pattern to determine the 3D shape of the body part to which the sleeve is applied. For example, the positions of the circular dots 12 relative to other circular dots 12 or relative to the reference dot 14 may be compared to the relative positions of corresponding dots in both the unelongated pattern and known elongations and deformations of the pattern to determine the 3D shape of the body part. A 3D image of the body part is generated.

[52]Another example elastic sleeve 20, shown in figure 3, has a pattern formed of figures, wherein the figures are squares 22. The pattern is printed onto the outer surface of the elastic sleeve 10 although any suitable method may be used and the pattern may be alternatively integrated into the material of the sleeve or applied to the reverse side provided the pattern is visible on the outer surface of the sleeve in use. The squares 22 are deformable, such that when the elastic sleeve 20 is elongated in at least two dimensions, the shapes and sizes of the squares 22 changes, as shown in figure 4.

[53]A reference marker 24 is attached to the elastic sleeve 20. The reference marker 24 provides a scale for images of the elastic sleeve 20. The dimensions of the squares and/or their separation may be determined from the images of the sleeve 24 based on the scale provided by the reference marker 24.

[54] According to the example shown in figures 3 and 4, the reference marker 24 is attached when the elastic sleeve 20 is applied about the body part. In other examples, the reference marker may be attached to the sleeve prior to the sleeve being applied about the body part.

[55] A 3D image of the body may be generated as described above in relation to the sleeve 10. The reference marker 24 may be present in the obtained images of the sleeve 20.

[56]Figure 5 illustrates a flowchart of a method 30 of obtaining 3D geometric data of a body part. The method comprises, at step 32, providing an elastic item at least a portion of which comprises a pattern visible on the outer surface thereof wherein the pattern has a predictable deformation on elongation. The elastic item may be the elastic sleeve 10 or 20 as described above.

[57] The method comprises, at step 34, applying the elastic item about a body part such that the elastic item is elongated in at least one dimension.

[58] The method comprises, at step 36, acquiring images of the elastic item when applied to the body part wherein the images are acquired from a plurality of different orientations and/or positions. The images may be captured by an operator moving a camera moving on around the body part, with the operator moving the camera freely around the body part. In other examples, the camera may be moved on a fixed path around the body part, for example on a track. In other examples, the images may be captured with the camera in a fixed position and the patient moving the body part, for example rotating the body part.

[59] The method comprises, at step 38, processing said images to obtain 3D geometric data relating to the shape of the body part.

[60] Various elements and methods described herein may be implemented through the execution of machine-readable instructions by a processor. Figure 6 shows a processing system comprising a processor in association with a non-transitory machine-readable storage medium. The machine-readable storage medium may be a tangible storage medium, such as a removable storage unit or a hard disk installed in a hard disk drive. The machine-readable storage medium comprises instructions to perform step (iv) of the first embodiment of the invention.

[61]Although the present disclosure includes certain embodiments, examples and applications, it will be understood by those skilled in the art that the present disclosure extends beyond the specifically disclosed embodiments to other alternative embodiments or uses and obvious modifications and equivalents thereof, including embodiments which do not provide all of the features and advantages set forth herein. Accordingly, the scope of the present disclosure is not intended to be limited by the specific disclosures of preferred embodiments herein, and may be defined by claims as presented herein or as presented in the future.

[62] Conditional language, such as "can," "could," "might," or "may," unless specifically stated otherwise, or otherwise understood within the context as used, is generally intended to convey that certain embodiments include, while other embodiments do not include, certain features, elements, or steps. Thus, such conditional language is not generally intended to imply that features, elements, or steps are in any way required for one or more embodiments or that one or more embodiments necessarily include logic for deciding, with or without user input or prompting, whether these features, elements, or steps are included or are to be performed in any particular embodiment. The terms "comprising," "including," "having," and the like are synonymous and are used inclusively, in an open-ended fashion, and do not exclude additional elements, features, acts, operations, and so forth. Also, the term "or" is used in its inclusive sense (and not in its exclusive sense) so that when used, for example, to connect a list of elements, the term "or" means one, some, or all of the elements in the list. Further, the term "each," as used herein, in addition to having its ordinary meaning, can mean any subset of a set of elements to which the term "each" is applied.

[63]Conjunctive language such as the phrase "at least one of X, Y, and Z," unless specifically stated otherwise, is otherwise understood with the context as used in general to convey that an item, term, etc. may be either X, Y, or Z. Thus, such conjunctive language is not generally intended to imply that certain embodiments require the presence of at least one of X, at least one of Y, and at least one of Z. [64] Language of degree used herein, such as the terms "approximately," "about," "generally," and "substantially" as used herein represent a value, amount, or characteristic close to the stated value, amount, or characteristic that still performs a desired function or achieves a desired result. For example, the terms approximately", "about", "generally," and "substantially" may refer to an amount that is within less than 10% of, within less than 5% of, within less than 1% of, within less than 0.1% of, and within less than 0.01% of the stated amount. As another example, in certain embodiments, the terms "generally parallel" and "substantially parallel" refer to a value, amount, or characteristic that departs from exactly parallel by less than or equal to 15 degrees, 10 degrees, 5 degrees, 3 degrees, 1 degree, or 0.1 degree.

[65]The scope of the present disclosure is not intended to be limited by the specific disclosures of preferred embodiments in this section or elsewhere in this specification, and may be defined by claims as presented in this section or elsewhere in this specification or as presented in the future. The language of the claims is to be interpreted broadly based on the language employed in the claims and not limited to the examples described in the present specification or during the prosecution of the application, which examples are to be construed as non-exclusive. [66]

Claims

WHAT IS CLAIMED IS1. Method of obtaining 3D geometric data of a body part comprising: (i) providing an elastic item at least a portion of which comprises a pattern visible on the outer surface thereof wherein the pattern has a predictable deformation on elongation (ii) applying the elastic item about a body part such that the elastic item is elongated in at least one dimension (iii) acquiring images of the elastic item when applied to the body part wherein the images are acquired from a plurality of different orientations and/or positions (iv) processing said images to obtain 3D geometric data relating to the shape of the body part.
2 The method of claim 1 wherein the elastic item is an elastic sleeve.
3. The method of claim 1 or claim 2 wherein the elastic item has a predictable deformation on elongation in at least two dimensions.
4. The method of any preceding claim wherein the method comprises the further step of using the 3D geometric data to generate a knitting pattern for a garment shaped to fit said body part
5. The method of any preceding claim wherein the garment is a compression garment for a patient in need thereof
6. The method of any preceding claim wherein images are acquired by a conventional digital camera or other commercially available handheld device.
7. The method of any preceding claim wherein processing said images comprises the step of comparing the acquired images with the undeformed pattern and/or known deformations of said pattern.
8. The method according to claim 7, wherein the pattern comprises a plurality of figures, and wherein comparing the acquired images with the undeformed and/or known deformations of said pattern comprises comparing shapes and/or relative positions of the figures of the pattern in the images with corresponding figures in the undeformed pattern and/or the known deformations of the pattern.
9. The method according to claim 8, wherein comparing shapes and/or relative positions of the figures comprises extracting sizes of the figures and/or distances between the figures from the images and comparing the extracted sizes and/or distances with corresponding sizes and or distances in the undeformed pattern and/or the known deformations of the pattern.
10. The method according to claim 9, wherein extracting the sizes and or distances comprises using a reference marker having known dimensions being present in the images, wherein the reference marker is attached to the elastic item.
11. An elastic sleeve for obtaining 3D geometric data of a body part wherein at least a portion of the elastic sleeve comprises a pattern visible on the outer surface thereof wherein, on elongation in at least two dimensions, the pattern deforms in a predictable and known manner.
12. The elastic sleeve according to claim 11, wherein the pattern comprises a plurality of figures, and wherein the shape of the figures and/or the spacing between the figures is configured to change on elongation of the elastic sleeve.
13. The elastic sleeve according to claim 11 or claim 12, further comprising a reference marker attachable to the elastic sleeve.
14. A computer program comprising instructions to execute step (iv) of the method of claim 1.
15. The computer program of claim 14 wherein step (iv) comprises the step of receiving image data that includes digital images of the elastic item when applied to the body part.
16. A computer-readable medium having stored thereon the computer program of claim 15.