Patent Description:
The meibomian glands (or tarsal glands) are a special kind of sebaceous gland at the rim of the eyelids inside the tarsal plate, responsible for the supply of meibum, an oily substance that prevents evaporation of the eye's tear film. Meibum prevents tear spillage onto the cheek, trapping tears between the oiled edge and the eyeball, and makes the closed lids airtight. Dysfunctional meibomian glands often cause dry eyes, one of the more common eye conditions. They may also cause blepharitis, as the dry eyeball rubs off small pieces of skin from the eyelid, which may get infected. Inflammation of the meibomian glands (also known as meibomitis, meibomian gland dysfunction, or posterior blepharitis) causes the glands to be obstructed by thick waxy secretions. Besides leading to dry eyes, the obstructions can be degraded by bacterial lipases, resulting in the formation of free fatty acids, which irritate the eyes and sometimes cause punctate keratopathy.

One treatment for such common eye conditions which is currently available comprises a pouch filled with a temperature control means. The pouch is disposed within a removable cover which, in use, contacts a subject's eyes and a surrounding area thereof and the temperature control means modulate the temperature of the cover, and thereby heats the subject's eyes and the surrounding area. After the heat treatment has been applied the subject can massage the area around their eyes and wipe away any debris. The device, when used in this method, treats, prevents or ameliorates the eye condition.

However, the inventors have found that in use bacteria from the eye can be transferred to the removable cover. The bacteria can then re-infect the eyes of a user on subsequent use of the cover. Furthermore, the temperature of the temperature control means can be affected by the external environment leading to variations in temperature.

<CIT> describes a pad for treating eye conditions. The pad comprises a multipart container having an impermeable outer membrane sized to fit generally within the peri-orbital region and sufficiently flexible to mold to the eye. The pad further comprises a first chemical in a first storage area in the multipart container and a second chemical in a second storage area in the multipart container. The first and second chemicals are selected to have an exothermic reaction when mixed for producing a temperature suitable for treating eye conditions.

<CIT> describes an article for therapy and treatment of an eye. The article includes a backing for application to the eye. The backing includes at least one receiver positioned to align with the eye. The article also includes at least one pod that is detachably secured within the at least one receiver. The at least one pod includes material for delivering therapy and treatment to the eye.

<CIT> describes an apparatus for treating dry eye. The apparatus comprises a patch or strip affixed to the skin of the upper and/or lower eyelids to deliver heat or other forms of energy, pressure, drugs, moisture, etc. (alone or in combination) to the one or more meibomian glands contained within the underlying skin. The treatment strip or strips include one or more strips configured to adhere to an underlying region of skin in proximity to one or both eyes of a subject such that the one or more strips allow for the subject to blink naturally without restriction from the one or more patches.

<CIT> describes a thermally adjustable compress assembly. The compress assembly includes a thermally adjustable gel pack and an external frame positionable against the outwardly facing surface of the gel pack. The external frame can be passively positionable against the gel pack to apply backward pressure against the gel pack during use or can be actively attached to the gel pack to provide additional support to at least a portion of the gravitational weight of the gel pack during use.

<CIT> describes an eye compress comprising a cover and fillers. The cover is formed by facing a pair of cotton sheets and sewing the edges of the cotton sheets. The fillers are put into the cover and are made of stone capable of irradiating far infrared rays. The cover is coated with one or more selected from silver, gold, and platinum.

<CIT> describes a heating tool which may be attached to the skin of a user, may warm the skin and supply oil thereto. The heating tool includes an adhesive layer which has a specific heat of less than <NUM> J/g·K at <NUM>° C. The adhesive layer includes a base and oil with a specific heat of less than <NUM> J/g·K at <NUM>° C and a boiling point of <NUM>° C or higher at <NUM> atmospheric pressure, and the oil is contained in an amount of <NUM> to <NUM> wt % in the adhesive layer.

<CIT> describes a cooling eye compress. The compress comprises a phase change material.

<CIT> describes a multifunctional eye bandage. The eye bandage comprises silver nanoparticles which have antibacterial and deodorising properties. <CIT> explains that silver nanoparticles and tourmaline, a material which emits far infra-red rays, can be contained in that material out of which the eye patch is made.

<CIT> is concerned with building materials and other construction components. In particular, <CIT> discloses a material for energy management and peak energy reduction in a building structure.

<CIT> relates to antimicrobial compositions which may be used with medical devices, such as catheters and implants.

<CIT> relates to compositions comprising silver nanoparticles for treating eyelash and eyelid margin infections.

The present invention arises from the inventor's work in attempting to overcome the problems associated with the prior art.

Hence, according to a first aspect of the invention, there is provided a medical device for treating, preventing or ameliorating an eye condition, the device comprising a cover, at least a portion of which comprises an antimicrobial agent and is at least partially filled with temperature control means, wherein, the antimicrobial agent comprises silver, or a pharmacologically acceptable salt thereof, and an oxide, wherein the oxide is selected from the group consisting of copper oxide, iron oxide, zinc oxide, titanium dioxide and silica dioxide, and, in use, the cover is arranged to contact a subject's eye and/or a surrounding area thereof, and wherein the temperature control means is configured to modulate the temperature of the cover to thereby treat, prevent or ameliorate the eye condition.

Advantageously, and preferably, the antimicrobial agent is configured to kill unwanted micro-organisms (e.g. yeast and/or bacteria) that comes into contact with the cover, and thereby prevents infection and/or reinfection of the subject's eye. Preferably, the device is used to prevent the eye condition from occurring in the first place or reoccurring, because it improves eyelid hygiene by ensuring that the meibomian glands are kept clean. It achieves this by effectively dissolves debris and bacteria etc. present within the oily meibum produced by the meibomian glands. It will be appreciated that use of the medical device of the invention is the first step in eye/eyelid hygiene followed by massage of the eye and/or the surrounding area thereof, and removal of any debris. Effective use of the device of the invention, therefore, improves eye hygiene, and confidential trials have shown that use of such a device can effectively treat many eye conditions.

Preferably, the cover is made of a material which effectively dissipates heat to a user's eye and surrounding area, when the device is in use. A first side of the cover may be made of a first material, which dissipates heat when the device is in use, at a greater rate than that of a second side of the cover made of a second material. For example, the first material may comprise synthetic or naturally occurring fibres. Preferably, the first material comprises naturally occurring fibres. Examples of the first material include cotton, silk, satin, or polyester. Silk is preferred.

The second material may comprise velvet, velour or suede. However, in a preferred embodiment, the second material may comprise a phase change material (PCM).

Advantageously, the PCM thermally regulates the temperature of the device, thereby ensuring a roughly consistent temperature is delivered to the eyes of the subject. Furthermore, the PCM reduces loss of heat to the environment, thereby allowing the temperature to be delivered for an extended period of time.

The first material may be configured to dissipate heat, when the device is in use, at a greater rate than that of the second side of the cover made of the second material. For example, the first material may comprise synthetic or naturally occurring fibres. Preferably, the first material comprises naturally occurring fibres. Examples of the first material include cotton, silk, satin, or polyester. Silk is preferred.

The second material may comprise fibres with the PCM located therein. However, in a preferred embodiment, the second material comprises a fabric with a layer of the PCM disposed thereon. Preferably, the layer of the PCM is disposed on an internal and/or external surface of the fabric. More preferably, the layer of the PCM is disposed on the internal surface of the fabric. The fabric may comprise synthetic or naturally occurring fibres.

Preferably, the device comprises a pouch disposed within the cover and is at least partially filled with the temperature control means. Preferably, the cover is removable. Accordingly, the pouch may be removably disposed in the cover.

It may be appreciated that the internal surface is the surface that is disposed substantially adjacent to, and preferably contacts, the temperature control means or, in embodiments where it is present, the pouch.

Preferably, the antimicrobial agent is configured to contact a person's eye without causing damage or irritation thereto. The antimicrobial agent may comprise a cationic surfactant. The cationic surfactant preferably comprises benzalkonium chloride (BKC). Advantageously, BKC is used in eye drops and contact lens solutions, and may safely contact a person's eye. Alternatively, or additionally, the antimicrobial agent may comprise a polymer. Preferably, the polymer comprises a biguanide polymer, more preferably polyaminopropyl biguanide (PAPB).

Advantageously, a polymer would not migrate into a user's skin.

The polymer may have an average molecular weight between <NUM>,<NUM> and <NUM>,<NUM>, more preferably between <NUM>,<NUM> and <NUM>,<NUM>.

The antimicrobial agent comprises silver or a pharmaceutically acceptable salt thereof.

Pharmaceutically acceptable salts include any salt which retains its biological properties and which is not toxic or otherwise undesirable for pharmaceutical use. The pharmaceutically acceptable salt may be derived from a variety of organic and inorganic counter-ions well known in the art.

Accordingly, the salt may be a halide, a sulphate or a nitrate.

Preferably, the antimicrobial agent may comprise a silver salt. The silver salt may be selected from the group consisting of silver sulphate, silver nitrate, silver chloride, silver sodium zirconium hydrogen phosphate and silver sulfadiazine.

Preferably, the oxide is titanium dioxide.

Preferably, the antimicrobial agent comprises a silver salt and titanium dioxide. Preferably the silver salt is silver chloride.

Preferably, the weight ratio of the metal, or the salt thereof, to the oxide is between <NUM>:<NUM> and <NUM>:<NUM>, more preferably between <NUM>:<NUM> and <NUM>:<NUM> or between <NUM>:<NUM> and <NUM>:<NUM>, and most preferably between <NUM>:<NUM> and <NUM>:<NUM> or between <NUM>:<NUM> and <NUM>:<NUM>.

Preferably, an external surface of the first side of the cover comprises the antimicrobial agent. It may be appreciated that, the first side of the cover, and more specifically external surface thereof, is configured to contact the user's eye. Alternatively or additionally, an internal surface of the first side of the cover may comprise the antimicrobial agent.

Preferably, the concentration of the antimicrobial agent is at least <NUM> x <NUM>-<NUM> mol/cm<NUM>, more preferably at least <NUM> x <NUM>-<NUM> mol/cm<NUM> or at least <NUM> x <NUM>-<NUM> mol/cm<NUM>, and most preferably at least <NUM> x <NUM>-<NUM> mol/cm<NUM>, at least <NUM> x <NUM>-<NUM> mol/cm<NUM> or at least <NUM> x <NUM>-<NUM> mol/cm<NUM>. Preferably, the concentration of the antimicrobial agent is less than <NUM> x <NUM>-<NUM> mol/cm<NUM>, more preferably less than <NUM> x <NUM>-<NUM> mol/cm<NUM> or less than <NUM> x <NUM>-<NUM> mol/cm<NUM>, and most preferably less than <NUM> x <NUM>-<NUM> mol/cm<NUM>, less than <NUM> x <NUM>-<NUM> mol/cm<NUM> or less than <NUM> x <NUM>-<NUM> mol/cm<NUM>. Preferably, the concentration of the antimicrobial agent is between <NUM> x <NUM>-<NUM> mol/cm<NUM> and <NUM> x <NUM><NUM> mol/cm<NUM>, more preferably between <NUM> x <NUM>-<NUM> mol/cm<NUM> and <NUM> x <NUM>-<NUM> mol/cm<NUM> or between <NUM> x <NUM>-<NUM> mol/cm<NUM> and <NUM> x <NUM>-<NUM> mol/cm<NUM>, and most preferably between <NUM> x <NUM>-<NUM> mol/cm<NUM> and <NUM> x <NUM>-<NUM> mol/cm<NUM>, between <NUM> x <NUM>-<NUM> mol/cm<NUM> and <NUM> x <NUM>-<NUM> mol/cm<NUM> or between <NUM> x <NUM>-<NUM> mol/cm<NUM> and <NUM> x <NUM>-<NUM> mol/cm<NUM>.

Alternatively, or additionally, the fabric of the cover may comprise at least <NUM> parts by weight of the antimicrobial agent. More preferably, the fabric of the cover comprises at least <NUM> of the antimicrobial agent. Most preferably, the fabric of the cover comprises at least <NUM> of the antimicrobial agent. Preferably, the fabric of the cover may comprise between <NUM> and <NUM> parts by weight of the antimicrobial agent. More preferably, the fabric of the cover comprises between <NUM> and <NUM> of the antimicrobial agent. Most preferably, the fabric of the cover comprises between <NUM> and <NUM> of the antimicrobial agent.

The pouch may also comprise the antimicrobial agent.

The device may be used to alleviate or treat a condition selected from the group of: styes, cysts, inflammation, dry eye disease, grittiness, irritation, itchy eyes (e.g. caused by hay fever), Meibomian Gland Dysfunction (MGD), Meibomian Gland Disease, Meibomian Gland Inspissation, chalazion, blepharitis, hordeolum, conjunctivitis, hay fever, headaches, tired or sore eyes, swelling/puffy eyes, allergies, and migraines.

Preferably, the temperature control means comprises grain or seed. For example, the temperature control means may be selected from a group of grain or seed consisting of: millet, rapeseed, canary seed, flax seed and wheat. In some embodiments, the temperature control means may comprise one or more type of seed or grain. Preferably, the temperature control means comprises at least two, at least three, or at least four different types of seed or grain. For example, the temperature control means may comprise a combination of wheat and flax (e.g. <NUM>% of each), or alternatively a combination of rapeseed, flax and millet (e.g. about <NUM>/<NUM> of each), and so on. Any combination of the seeds and grains described herein is envisaged. In a preferred embodiment, however, the temperature control means comprises a combination of canary seed, rapeseed and millet seed, more preferably about <NUM>-<NUM>% of each of canary seed, rapeseed and millet, and most preferably, a combination of about <NUM>-<NUM>% of each of canary seed, rapeseed and millet.

In another embodiment, the temperature control means may comprise tourmaline beads. Tourmaline is a crystalline boron silicate mineral which can be produced into small beads.

In a most preferred embodiment, however, the temperature control means comprises silica beads or silica gel. The silica beads or gel may comprise an average diameter of at least <NUM>, more preferably at least <NUM>, and even more preferably at least <NUM>. Preferably, the silica beads or gel may comprise an average diameter of less than <NUM>, more preferably less than <NUM>, and even more preferably less than <NUM>. Preferably, the silica beads or gel may comprise an average diameter of between <NUM> and <NUM>, more preferably between <NUM> and <NUM>, and more preferably between <NUM> and <NUM>.

It will be appreciated that the optimum temperature of the eyelids does not exceed much more than <NUM>. In one embodiment, the temperature control means is configured to be heated, preferably to above room temperature, i.e. above <NUM>. Preferably, the temperature control means is configured to be heated to above <NUM>, more preferably above <NUM>, and even more preferably above <NUM>. Preferably, the temperature control means is configured to be heated to below <NUM>, more preferably below <NUM>, and even more preferably below <NUM>. Preferably, the temperature control means is configured to be heated to between <NUM> and <NUM>, more preferably to between <NUM> and <NUM>, even more preferably to between <NUM> and <NUM>. The temperature control means may be heated by microwave energy, for example using a domestic microwave oven. Alternatively, it could be heated using a conventional oven. When contacted with the user, the heat is suitably transferred from the device to the user's eye or surrounding area.

Preferably, in this embodiment, the PCM has a transition temperature above room temperature, i.e. above <NUM>. Preferably, the PCM has a transition temperature above <NUM>, more preferably above <NUM>, and even more preferably above <NUM>. Preferably, the PCM has a transition temperature below <NUM>, more preferably below <NUM>, and even more preferably below <NUM>. Preferably, the PCM has a transition temperature between <NUM> and <NUM>, more preferably between <NUM> and <NUM>, even more preferably between <NUM> and <NUM>.

Preferably, the device is heated to treat any of the following conditions: styes, cysts, dry eye disease, grittiness, irritation, itchy eyes (e.g. caused by hay fever), Meibomian Gland Dysfunction (MGD), Meibomian Gland Disease, Meibomian Gland Inspissation, chalazion, blepharitis, and hordeolum.

In an embodiment in which the temperature control means comprises silica beads or silica gel and is configured to be heated, preferably the silica comprises an average diameter of between <NUM> and <NUM>, more preferably between <NUM> and <NUM>, and more preferably between <NUM> and <NUM>. Advantageously, the silica fits better around the glands in the eyelid.

Additionally, or alternatively, the temperature control means is arranged, in use, to be cooled, preferably to less than room temperature, i.e. less than <NUM>. Preferably, the temperature control means is configured to be cooled to below <NUM>, more preferably below <NUM>, even more preferably below <NUM>, and most preferably below <NUM>. Preferably, the temperature control means is configured to be cooled to above -<NUM>, and more preferably above -<NUM>, even more preferably above -<NUM>. The temperature control means may be cooled by placing the device in a domestic fridge or freezer.

Preferably, in this embodiment, the PCM has a transition temperature which is less than room temperature, i.e. less than <NUM>. Preferably, the PCM has a transition temperature which is less than <NUM>, more preferably less than <NUM>, even more preferably less than <NUM>, and most preferably less than <NUM>. Preferably, the PCM has a transition temperature which at least -<NUM>, and more preferably at least -<NUM>, even more preferably at least -<NUM>.

Preferably, the device is cooled to treat any of the following conditions: inflammation, irritation, itchy eyes (e.g. caused by hay fever), conjunctivitis, hay fever, headaches, tired or sore eyes, swelling/puffy eyes, allergies, and migraines.

When contacted with the user, the cooling energy is suitably transferred from the device to the user's eye or surrounding area. In this embodiment, the temperature control means may comprise seed or grain. Examples of grain, seed, tourmaline beads and/or silica beads or silica gel which may be used in the cooling embodiment are described above. However, in another embodiment, the temperature control means may comprise cooling crystals, which are configured to cool down when contacted with water.

In a preferred embodiment (when cooling is desired), the temperature control means comprises a cooling gel. The cooling gel preferably comprises silica beads or silica gel. The gel in the pouch may be put into a fridge or freezer, and when it is removed, the user preferably manipulates it to loosen it and make it pliable so that the pouch and cover mould around the eyes and surrounding areas.

In an embodiment in which the temperature control means comprises silica beads or gel and is configured to be cooled, preferably the silica comprises an average diameter of between <NUM> and <NUM>, more preferably between <NUM> and <NUM>, and more preferably between <NUM> and <NUM>. Advantageously, this size of silica retains the cold better than smaller beads.

Preferably, at least <NUM>%, preferably at least <NUM>%, more preferably at least <NUM>%, and even more preferably at least <NUM>%, and most preferably at least <NUM>% of the volume of the cover or the pouch is filled with the temperature control means. Suitably, the temperature control means occupies less than <NUM>%, preferably less than <NUM>%, more preferably less than <NUM>% of the volume of the cover or the pouch. It is preferred that the temperature control means occupy between about <NUM>% and <NUM>%, more preferably between about <NUM>% and <NUM>% of the volume of the space, most preferably between about <NUM>% and <NUM>% of the volume of the space.

Advantageously, this allows the temperature control means to be easily redistributed around the cover or the pouch after heating or cooling so that the user can ensure that there is an even distribution thereof to the eye and surrounding area (i.e. from above, below and either side of the eye socket), thereby maximising pain relief. Furthermore, it facilitates equalisation of the temperature throughout the mass of temperature control means, thereby reducing the risk of hotspots being created (when warmed), or ice "burn" occurring (when cooled), when the device is in use.

Preferably, the pouch is made of a material which effectively dissipates heat through the cover and towards a user's eye and surrounding area, when the device is in use. For example, the pouch may be made of a textile, such as cotton, silk, satin, or polyester. Cotton is preferred, especially in embodiments where the device is heated. However, in embodiments where the device is cooled, the pouch may comprise a waterproof material, for example latex or rubber. The pouch may comprise a label attached thereto, wherein the label comprises instructions for use of the device.

In one embodiment, the shape of the cover may be such that it fit's over only one eye of the subject, leaving the other eye exposed. Advantageously, this would allow the medical device to target a specific eye of a user.

In an alternative embodiment, the material and shape of the cover is such that it fits comfortably over both of the subject's eyes, and moulds therearound providing effective heat transfer. The cover preferably comprises a central section which is arranged, in use, to overlie the subject's nose, and two side sections disposed either side of the central section, which are arranged, in use, to overlie the subject's eyes and surrounding areas. Preferably, the maximum width of the central section is less than the maximum width of the side sections. For example, the width of the central section may be between about <NUM> and <NUM> across, or between about <NUM> and <NUM> across. The width of each side section may be between about <NUM> and <NUM>, or between about <NUM> and <NUM> across. The maximum length of the cover is preferably at least <NUM>, more preferably at least <NUM>, and even more preferably at least <NUM>.

The removable cover may comprise an opening through which the pouch may pass. The opening may be disposed on an external surface of the cover, preferably on the second side thereof. The second side is generally regarded as being the front surface of the device. The second side of the cover preferably comprises two pieces of material, which overlap each other thereby creating the opening. Preferably, the opening leads to a pocket disposed between the first and second sides of the cover, which pocket is configured to receive the pouch containing the temperature control means. The opening preferably extends diagonally across the first side of the cover, preferably along a line which extends across one of the side sections. The diagonal arrangement allows easier access of the pocket without interfering directly with the eye.

Preferably, the device comprises retaining means for securing the device (preferably the cover thereof) to the user's head and in position over the eye and/or surrounding area thereof. The retaining means may comprise at least one strap, which may be elasticated. Preferably, the retaining means comprises two straps, each strap being attached to mutually opposing ends of the cover, and arranged to be secured to each other to provide adjustability. Preferably, the retaining means comprises fastening means, for example one or more corresponding hook and loop fastening regions, such as Velcro regions.

According to a second aspect, there is provided a method of preparing the device of the first aspect for use in a method of treatment, the method comprising modulating the temperature of the device, and manipulating the device to redistribute the temperature control means around the cover.

According to a third aspect, there is provided a method of manufacturing a medical device, the method comprising:.

wherein the cover is at least partially filled, or adapted to be at least partially filed, with temperature control means, and, in use, the cover is arranged to contact a subject's eye and/or a surrounding area thereof, and wherein the temperature control means is configured to modulate the temperature of the cover to thereby treat, prevent or ameliorate the eye condition.

Preferably, the method of the third aspect produces the medical device of the first aspect.

Allowing the cover to dry may comprise heating the cover above ambient temperature for a pre-determined time.

Accordingly, the method may comprise heating the cover to at least <NUM>, preferably at least <NUM>, more preferably at least <NUM>, and most preferably at least <NUM>. The method may comprise heating the cover to less than <NUM>, preferably less than <NUM>, more preferably less than <NUM>, and most preferably less than <NUM>. The method may comprise heating the cover to between <NUM> and <NUM>, preferably between <NUM> and <NUM>, more preferably between <NUM> and <NUM>, and most preferably between <NUM> and <NUM>.

The pre-determined time may be at least <NUM> minutes, preferably at least <NUM> or <NUM> minutes, more preferably at least <NUM> hour <NUM> minutes. The pre-determined time may be less than <NUM> hours, preferably less than <NUM> hours or <NUM> hours, more preferably less than <NUM> hours <NUM> minutes. The pre-determined time may be between <NUM> minutes and <NUM> hours, preferably between <NUM> minutes and <NUM> hours or between <NUM> minutes and <NUM> hours, more preferably between <NUM> hour <NUM> minutes and <NUM> hours <NUM> minutes.

The method may comprise allowing the cover to cool to room temperature.

According to a fourth aspect, there is provided a kit to make a medical device, the kit comprising.

wherein, in use, the cover is arranged to contact a subject's eye and/or a surrounding area thereof, and wherein the temperature control means is configured to modulate the temperature of the cover to thereby treat, prevent or ameliorate an eye condition.

Advantageously a person provided with the kit of the fourth aspect could conduct the method of the third aspect to create the medical device. Furthermore, the person could apply the solution after the device is washed, ensuring that the desired concentration of the antimicrobial agent is maintained.

All features described herein (including any accompanying claims, abstract and drawings), and/or all of the steps of any method or process so disclosed, may be combined with any of the above aspects in any combination, except combinations where at least some of such features and/or steps are mutually exclusive.

For a better understanding of the invention, and to show how embodiments of the same may be carried into effect, reference will now be made, by way of example, to the accompanying drawings, in which:-.

The inventors asked volunteers to wear prior art eye-masks. Testing of the eye-masks identified that bacteria was transferred to all of the eye masks tested, and in some instances mould was also transferred. The inventors have found that it is not possible to kill these microbes using a microwave.

The inventors work seeks to overcome this problem.

Referring to the Figures, there is shown a medical device <NUM>, which consists of an outer cover <NUM> and an inner pouch <NUM> disposed therein. <FIG> illustrate various views of the cover <NUM>, <FIG> shows the pouch <NUM>, and <FIG> shows the device <NUM> in position on a subject <NUM>. In use, the device <NUM> is either heated by a conventional microwave, or cooled in a conventional fridge/freezer, and is effectively used to treat or even prevent a very wide range of eye conditions, such as styes and cysts, inflammation, dry eye disease, grittiness and irritation, itchy eyes (e.g. caused by hay fever), Meibomian Gland Dysfunction (MGD), chalazion, blepharitis and conjunctivitis, and so on, depending on whether heating or cooling of the eyes and the associated areas is desired. It will be appreciated however that this list of eye conditions is not exhaustive and that the device <NUM> can be used to treat or prevent any kind of eye pain or condition, or to soothe a headache, which may have been caused by eye strain. Use of the medical device <NUM> is the first step in eye/eyelid hygiene followed by the application of eyedrops etc to treat an eye condition. Effective use of the device <NUM> improves eye hygiene such that the chances of many eye conditions occurring are significantly reduced or prevented.

Referring first to <FIG>, the back of the outer cover <NUM> of the device <NUM> is shown, and is composed of a single piece of material <NUM>, for example soft cotton or silk. The rear piece of material <NUM> is generally light blue or white in colour, and so will not emit heat to the same extent as a black piece of material would. As described in more detail in example <NUM>, below, the rear piece of material also comprises an antimicrobial agent.

Referring to <FIG>, the front of the outer cover <NUM> of the device <NUM> is shown, and is composed of two pieces of material 6a, 6b, for example soft cotton or silk. In the embodiment illustrated, the two pieces of material 6a, 6b comprise a phase change material (PCM) which is configured to absorb, store and release heat. Suitable PCMs are sold under the trade mark Outlast® and are described in a variety of patent applications, for instance see <CIT>, <CIT>, <CIT> and <CIT>. The PCM helps to thermally regulate the temperature of the device <NUM>, ensuring a roughly consistent temperature is delivered through the rear piece of material <NUM> for an extended period of time.

The perimeter of the front piece of material <NUM> is stitched to the two rear pieces of material 6a, 6b by a line of stitching <NUM>, and rear pieces 6a, 6b are stitched to each other only at their peripheral edges, as shown in <FIG>.

As can be seen in <FIG>, an adjustable comfort strap <NUM> is secured to each side of the cover <NUM>. Each strap <NUM> is approximately <NUM> in length, and is stitched <NUM> to each side of the rear piece of material <NUM>. As can be seen in <FIG>, each end of the straps <NUM> distal from the stitching <NUM> is covered with an area of Velcro® <NUM>. In use, the subject <NUM> can easily adjust the tightness of the outer cover <NUM> around the head and over the eyes <NUM> by varying the combined length of the straps <NUM> via the respective positioning of the Velcro (RTM) regions <NUM>.

As shown in <FIG>, the shape of the cover <NUM> is such that it fits comfortably around the subject's head and over their eyes <NUM>. The cover <NUM> has a narrow central section <NUM> which is arranged, in use, to overlie the subject's nose <NUM>, and two wide side sections <NUM> disposed either side of the central section <NUM>, which are arranged, in use, to overlie the subject's eyes <NUM>. The width of the central section <NUM> is about <NUM> across and is therefore narrower than the width of each side section <NUM>, which is about <NUM> across. The length of the entire cover <NUM> (excluding the straps <NUM>) is approximately <NUM> across.

As shown in <FIG>, the front piece of material 6a forming the outer cover <NUM> extends across about <NUM>% of the width of the rear of the cover <NUM>, and over a small section of the front piece of material 6b, thereby creating a small overlap. The pieces 6a, 6b are not stitched together at the overlap, and so an opening <NUM> is created, which leads to a pocket <NUM> that is disposed between the rear piece of material <NUM> and the two front pieces of material 6a, 6b. The opening <NUM> extends diagonally across the front surface <NUM> of the cover <NUM>, generally along a side region <NUM> thereof. The opening <NUM> is suitably sized to enable the insertion of the inner pouch <NUM>, which is shown in detail in <FIG>, and described below.

Referring now to <FIG>, the inner pouch <NUM> consists of two pieces of thin material, such as cotton, which are stitched together to create a flexible sack or bag. The material of the pouch <NUM> may also comprise an antimicrobial agent. The shape of the pouch <NUM> resembles that of the front <NUM> and rear <NUM> surfaces of the outer cover <NUM>, although the dimensions are slightly less so that the pouch <NUM> can be easily removed and inserted though the opening <NUM> in the cover <NUM>. Thus, as can be seen in the Figure, the pouch <NUM> has a narrow central region <NUM>, which corresponds to the narrow central region <NUM> of the outer cover <NUM>, and wider side regions <NUM>, which correspond to the wider side regions <NUM> of the cover <NUM>. Stitched to one of the side regions <NUM> of the pouch <NUM>, there is provided a label <NUM> on which instructions <NUM> for use are clearly printed.

In a first embodiment of the device <NUM>, the pouch <NUM> contains a plurality of microwaveable grains or seeds <NUM>. For instance, the grains may be a special mix of natural seeds (e.g. <NUM>% canary seed, <NUM>% rapeseed, and <NUM>% millet seed), which has been developed to ensure that the device <NUM> warms to the correct temperatures in the least amount of time, and then retains the heat for as long as possible, and at a comfortable level when worn by the subject <NUM>. Other grains that may be used are flax seed or wheat, either alone or in combination with the other grains described herein. Alternatively, silica beads can also be used, and are described in more detail in <CIT>. This embodiment is used for microwaving and transferring heat to the subject <NUM>, as will be described below.

The embodiment of the device <NUM> described above may also be used to apply a cooling effect to a subject's eyes. Alternatively, in a second embodiment of the device <NUM>, where the subject's eyes <NUM> require a cooling effect, instead of being filled with microwaveable grains, seeds and/or beads <NUM>, the pouch <NUM> contains a cooling gel or alternatively polymer cooling crystals, or the like (not shown). An example of a suitable cooling gel is available from Yangzhou Tianle Hot Water Bottle Factory (China). In use, when exposed to cold temperatures (i.e. from a conventional fridge or freezer), the gel cools down and retains the cool temperature. Suitable cooling crystals (available from N-rit co. , ltd, #<NUM>-<NUM>, Seoknam2-Dong, Seo-gu, Incheon City, Korea <NUM>-<NUM>), can also be used to cool down the device <NUM>, but without the need for a freezer. To cool the device <NUM>, it is first immersed in cold water for <NUM>-<NUM> minutes until the high-tech polymer crystals fully absorb the water and become "activated". It may be desirable to also place the activated crystals in a fridge for <NUM> minutes for an even greater cooling effect. The crystals are made of a non-toxic crystal polymer, which becomes cold, and has a long-lasting cooling effect. The subject <NUM> can enjoy the soothing, cooling effect imparted by the crystals.

For clarity, <FIG> does not show a full complement of grains, seeds and/or beads <NUM> (or cooling gel/crystals); instead it shows, for illustrative purposes only, small groupings of grains <NUM> at various positions within the pouch <NUM>. However, it should be appreciated that the pouch <NUM> contains enough grains, seeds and/or beads <NUM> (or cooling gel/crystals) to be fully dispersed throughout, such that the subject's eyes <NUM> and surrounding areas are fully covered when the device <NUM> is placed in the correct position. Conversely, the pouch <NUM> is not completely filled with grains, seeds and/or beads <NUM> (or cooling gel/crystals) so that the subject <NUM> can easily move them around the inside the pouch <NUM> to avoid hot/cold spots. Also, the subject <NUM> is able to easily insert the pouch <NUM> through opening <NUM> into the pocket area <NUM>. As a guide, the pouch <NUM> is filled to about <NUM>-<NUM>% of its capacity with the grains, seeds and/or beads <NUM> (or cooling gel/crystals).

While not illustrated, it will be appreciated that in an alternative embodiment the grains, seeds and/or beads <NUM> (or cooling gel/crystals) may be disposed directly in the cover <NUM>. Accordingly, in this embodiment, the device <NUM> would not comprise a pouch <NUM>. Furthermore, the front of the cover <NUM> may comprise a single piece of fabric, such that the cover does not comprise an opening <NUM>.

In use, the subject <NUM> must first remove the inner pouch <NUM> from the outer cover <NUM> by carefully pulling it out. The relatively sizes of the pouch <NUM> and cover <NUM> mean that it is not a very tight fit, and so there is no risk that the pouch would be ripped and lose its contents during the removal operation. The subject <NUM> then places the pouch <NUM> on a clean microwaveable plate, and heats it on full power (based on a <NUM>-<NUM> Watt microwave) for approximately <NUM> seconds. Heating times should never be exceeded. The microwave energy is absorbed by the grains <NUM>, which are therefore heated up to an elevated temperature of about <NUM>-<NUM>. After heating, the pouch <NUM> is then inserted into the outer cover <NUM> through the opening <NUM> and then arranged such that it fits well within the pocket area <NUM>, in an extended configuration therein, i.e. the positions of the central region <NUM> and side regions <NUM> of the pouch <NUM> correspond with the positions of the central region <NUM> and side regions <NUM> of the outer cover <NUM>.

Alternatively, in the embodiment where the grains, seeds and/or beads <NUM> (or cooling gel/crystals) are disposed directly in the cover <NUM>, the subject <NUM> may simply heat the cover <NUM> in the microwaveable.

In order to distribute the heat effectively, and to prevent any "hot spots" developing, the device <NUM> can be shaken during (e.g. about half-way) through the heating period, and again after heating, but before use. Once fully heated, the subject <NUM> then carefully checks the temperature of the grains <NUM> by touching the outer cover <NUM> (now containing the heated pouch <NUM>) on to the inside of the wrist, before putting on the eyes <NUM>. To avoid damage to the eyeball, the subject <NUM> must close the eyes <NUM> prior to gently resting the outer cover <NUM> of the device <NUM> in place, as illustrated in <FIG>. The rear <NUM> of the outer cover <NUM> is contacted on the subject's eyes, and the front <NUM> is exposed to the air.

The straps <NUM> are then fastened together via the Velcro (RTM) <NUM> forming a headband. The pressure that is applied by the device <NUM> to the subject's eyes <NUM> can be adjusted by tightening or loosening the straps <NUM> to suit personal comfort. The device <NUM> gently conforms and moulds to the contours of the eyes <NUM> and shape of the subject's face, and is left in position for <NUM> to <NUM> minutes, or longer if desired. Due to the two pieces of material 6a, 6b comprising the PCM, the inventors have found that the device is capable of maintaining the temperature between <NUM> and <NUM> in excess of ten minutes. The straps <NUM> provide tight support and even distribution of the grain <NUM> to the eyes and surrounding areas, thereby maximising pain relief.

After using the device <NUM>, with the eyes closed, the subject <NUM> then gently massages the upper eyelid by smoothing a finger from the inner corner of the eye <NUM> to the outer corner just above the lashes. This procedure is then repeated just below the lashes on the lower lid. Debris should then be removed from the subject's eyes <NUM> and the surrounding area. The exercise should be repeated for about a minute on both eyes. The device can be used two or three times a day, but can be reduce to <NUM>-<NUM> times a week once the symptoms improve.

It is widely recognised and accepted that warmth eases pain and helps movement in muscles and joints, by increasing vasodilation and therefore blood flow to restricted areas. Accordingly, the device <NUM> is useful for treating a range of conditions, which would benefit from such soothing heat treatment. However, it is also possible to use the device <NUM> when it is cold, rather than warm (following microwaving). Applying the device <NUM> when cold reduces pain and swelling by causing blood vessels to vasoconstrict. It has also been demonstrated by hay fever sufferers that cooling the eyes <NUM>, especially the corners thereof, results in a satisfying reduction in itchiness and irritation.

When wishing to cool the eyes <NUM>, the pouch <NUM> is first removed from the outer cover, and then placed inside a receptacle, such as a clean plastic bag (not shown), and left in the fridge or freezer for at least an hour. The cooled pouch <NUM> is then inserted back into the outer cover <NUM>, which is then gently placed over the eyes <NUM> and nose <NUM>. The subject <NUM> then increases the pressure of the device <NUM> over the eyes via the straps <NUM>, as described above, and allows the cool soothing effect to act. It is highly unlikely that the user would get ice burns from using the device <NUM> when chilled. However, for safety, it is preferred that the device <NUM> is not used for more than <NUM> minutes at any one time.

An antimicrobial solution comprising a biguanide polymer with a molecular weight between <NUM>,<NUM> and <NUM>,<NUM> as an antimicrobial agent was produced.

A trigger spray was used to apply the antimicrobial solution first to the internal surface of the back of the outer cover <NUM>, then to the external surface of the outer cover <NUM>. The devices <NUM> were then dried in a convection oven at <NUM> for <NUM> hours and were then allowed to cool to room temperature for <NUM> hours.

A solution comprising test species was prepared. The solution comprised:.

The solution comprising the test species was then spread over the external surface of the outer cover <NUM>. After <NUM> minutes the external surface of the outer cover <NUM> was swabbed to measure the recovery of live micro-organisms. The results are given in Table <NUM>, below. The mass of active agent was calculated assuming that <NUM>% of the added weight is the active agent. The concentration of the active agent was calculated assuming that the average molecular weight of the active agent was <NUM>,<NUM> and the surface area of the blind fold was <NUM><NUM> (<NUM><NUM> for the internal surface and <NUM><NUM> for the external surface).

It will be noted that the antimicrobial solution was effectively able to kill all of the test species.

An agar overlay test was designed to determine the cytotoxicity of the antimicrobial solution when applied to the outer cover <NUM>.

Six well cell culture plates were seeded with a verified quantity of industry standard L-<NUM> cells (ATCC CCL-<NUM>) and incubated at <NUM> ± <NUM> with <NUM> ± <NUM>% CO2 until approximately <NUM>% confluent. The agar overlay consisted of an equal mixture of <NUM>% noble agar and 2X Minimal Essential Media + <NUM>% bovine calf serum. Solid test articles were placed directly on the solidified agar overlay testing ≥ <NUM><NUM> per test well. Positive and negative reference controls were included with each assay.

All tests were performed using three test wells per test article. After the addition of the test articles, the cell culture plates were incubated as described above for <NUM>-<NUM> hours. Following incubation, cells were evaluated microscopically using the evaluation criteria outline in table <NUM>.

An antimicrobial solution comprising silver chloride and titanium dioxide, in a weight ratio of <NUM>:<NUM>, as an antimicrobial agents was produced and applied to a cotton fabric. Similar, treated fabric may be obtained from Polygiene®. The cotton fabric was used as the test sample. Polypropylene pellets were used as a negative control and latex natural rubber was used as a positive control.

The results from the agar overlay test are given in table <NUM>.

The United States Pharmacopeia & National Formulary (USP <<NUM>>) states that the test article meets the requirements if the reactivity grade is not greater than grade <NUM> or a mild reactivity. The ANSI/AAMI/ISO <NUM>-<NUM> standard states that the achievement of a numerical grade greater than <NUM> is considered a cytotoxic effect.

As indicated above, the cotton treated with antimicrobial solution received a score of <NUM>, and so is not deemed to be cytotoxic.

As explained in Example <NUM>, an antimicrobial solution comprising silver chloride and titanium dioxide, in a weight ratio of <NUM>:<NUM>, as an antimicrobial agents was produced and applied to a cotton fabric. A sample of the treated cotton fabric was washed equivalently to fifteen domestic cycles at <NUM> to determine if the treated fabric maintained its antimicrobial properties after washing.

An inoculum of Staphylococcus aureus prepared in <NUM>:<NUM> Nutrient Broth was prepared, and <NUM> samples of the inoculum were applied to replicate (<NUM>) samples of either the untreated fabric, the treated fabric or the treated and washed fabric. The number of colony forming units/cm<NUM> was calculated at the time of inoculation and then <NUM> hours later. The results are shown below in Table <NUM>.

The results show that the treated fabric has an antimicrobial effect reducing the bacteria to below the limit of detection over <NUM> hours. This equates to a ><NUM> log kill of the bacteria over the <NUM> hours. The same effect was observed for the treated fabric which had been washed fifteen times, showing that the fabric retains its antimicrobial properties after washing.

Conversely, the untreated fabric only showed a <NUM> log kill of the bacteria over <NUM> hours.

A further medical device <NUM> is shown in <FIG>. Like the medical device <NUM> discussed in Example <NUM>, the medical device <NUM> consists of an outer cover <NUM> and an inner pouch <NUM> disposed therein. However, unlike the device <NUM> discussed in example <NUM>, the outer cover <NUM> of the device <NUM> does not comprise an antimicrobial agent.

Instead, a disposable barrier <NUM> is provided to place over the back of the outer cover <NUM> before use. The disposable barrier <NUM> is sized and shaped to substantially correspond to the back of the outer cover <NUM>. The disposable barrier <NUM> comprises a sterile cotton gauze <NUM> with an adhesive disposed on a first side <NUM> thereof, and a backing strip <NUM> disposed over the adhesive. The disposable barrier <NUM> is disposed in a sterile pouch (not shown) prior to use. Accordingly, when a user wishes to use the device <NUM>, they may heat it as described in example <NUM>. They can then remove the disposable barrier <NUM> from the pouch, remove the backing strip <NUM> and affix the disposable barrier <NUM> to the back of the outer cover <NUM> before placing the device against their eyes <NUM>.

After use, the user can remove the disposable cover <NUM> from the outer cover <NUM> and dispose of it. Accordingly, the disposable cover <NUM> prevents microbes being transferred between the patient's eyes <NUM> and the outer cover <NUM>.

Advantages of the device <NUM> reside in the antimicrobial agent being able to effectively kill bacteria and fungus, thereby preventing infection or reinfection of a subject's eyes. Furthermore, the PCM material thermally regulate the temperature of the device <NUM>, ensuring a roughly consistent temperature is delivered to the eyes of the subject for an extended period of time.

Claim 1:
A medical device (<NUM>) for treating, preventing or ameliorating an eye condition, the device (<NUM>) comprising a cover (<NUM>), at least a portion of which comprises an antimicrobial agent and is at least partially filled with temperature control means (<NUM>), wherein, in use, the cover (<NUM>) is arranged to contact a subject's eye and/or a surrounding area thereof, and wherein the temperature control means (<NUM>) is configured to modulate the temperature of the cover (<NUM>) to thereby treat, prevent or ameliorate the eye condition characterised in that:
the antimicrobial agent comprises silver, or a pharmacologically acceptable salt thereof, and an oxide, wherein the oxide is selected from the group consisting of copper oxide, iron oxide, zinc oxide, titanium dioxide and silica dioxide.