Patent Application
20120248346
The present invention relates generally to protective shields worn by humans exposed to harmful ionizing radiation and, more specifically, to wearable shields used to protect healthcare providers, patients, security personnel and other operators of equipment that generates ionizing radiation. More specifically, the present invention relates to wearable radio-opaque shields in which one or more layers of particulate environmentally friendly radio-opaque material are encased between two containment layers. The present invention also relates generally to liners for radio-opaque shields.
Modern imaging technologies, such as x-ray, fluoroscopy, and computer tomography (CT), all of which employ ionizing radiation (e.g., x-rays, etc.), have revolutionized diagnostic radiology. The benefits of using imaging technologies are many: living tissues can be non-invasively visualized; radiographic techniques may now be used to diagnose conditions that were once identified with laparoscopic techniques; and diagnosis with radiography is noninvasive, fast and painless. As a result, by one estimate, in 2008 over 178 million x-rays were performed in the United States alone. Over 19,500 CT scans are performed in the United States each day, subjecting each patient to the equivalent of between 30 to about 500 chest radiographs per scan. Annually, about four million CT scans are performed on children. In flict, roughly half of all of the most advanced procedures that use ionizing radiation are conducted in the United States alone
Unfortunately, the increase in the use of radiographic procedures comes with a downside: the average American receives the highest per capita dosage of ionizing radiation in the world, with the average dose growing six-fold over the last couple of decades. With the increase in exposure to ionizing radiation comes an increased risk of long term damage (e.g., cancer, genetic damage that may affect future generations, etc.) to each individual exposed to ionizing radiation. The risk of radiation-induced damage is particularly prevalent among health care professionals who are repeatedly exposed to ionizing radiation, either directly or incidentally.
Recognition of the potentially grave effects of repeated exposure to ionizing radiation has led to the development of radiation-blocking garments. As an example, thyroid collars protect the thyroid gland, which is known to be extremely sensitive to ionizing radiation, from excessive kvels of ionizing radiation. Traditionally, radiation-blocking garments have been manufactured by dispersing lead (Pb) powder, or other heavy metal powders such as tungsten (W), antimony (Sb), tin (Sn) or mixtures of metals that attenuate ionizing radiation, throughout polymeric materials, such as rubber, vinyl and other elastomers. When lead or heavy metal powder particles are dispersed throughout a polymer, the resulting composite must be relatively thick and cumbersome to provide a desired level of radiation attenuation. Polymer-lead/heavy metal composites are also heavy and uncomfortable for clinicians, who often require protection from ionizing radiation for several hours in a typical day. With repeated use, radiation attenuating garments typically become soiled, for example, as the clinician sweats, by fluids from patients, etc. Unfortunately, conventional radiation attenuating garments are not configured for regular cleaning or sanitization. Thus, they can lack the level of hygiene typically associated with and expected of a healthcare setting.
While the use of thinner lead sheets or foils could provide comparable radiation protection with less weight, they lack the pliability needed for use in garments.
The use of materials other than lead, in conjunction with polymeric matrices, to attenuate ionizing radiation has resulted in some weight savings, Nonetheless, lead-free composites are often bulkier than lead-based composites, providing minor weight savings, and typically offering less protection from ionizing radiation than lead-based composites.
Various embodiments of wearable radio-opaque shields are disclosed. Wearable radio-opaque shields may also be more simply referred to herein as “shields” and as “articles.” The construction of a wearable radio-opaque shield may render it suitable for limited use, or cven for disposal after a single use. The phrase “limited use,” as employed herein, is intended to encompass wearable radio-opaque shields that are configured for temporary use, as well as single-use, or disposable, shields.
In some embodiments, a wearable radio-opaque shield may comprise a non-toxic radio-opaque material, which may lend to the disposability of the shield. A wearable radio-opaque shield may also have a light-weight construction, which may be at least partially attributable to the materials and amounts of materials that are used to form the shield. U.S. patent application Ser. No. 12/897,611 (the “'611 Application”), the entire disclosure of which is, by this reference, hereby incorporated herein, describes light-weight, non-toxic radio-opaque sheets from which a wearable radio-opaque shield may be fabricated. In a specific embodiment, the radio-opaque sheet used to form a wearable radio-opaque shield includes two flexible films between which radio-opaque material is captured.
A wearable radio-opaque shield may comprise a thyroid collar. When placed over the front of an individual's neck, a disposable thyroid collar prevents ionizing radiation to which the individual is exposed from reaching the individual's thyroid. A limited-use thyroid collar may be formed from relatively (when compared with conventional thyroid collars) inexpensive materials.
Alternatively, a wearable radio-opaque cap may prevent exposure of an individual's brain to ionizing, radiation. Such a shield may, accordingly, comprise a cap or other article configured to be worn on the individual's head.
A plurality of light-weight, wearable radio-opaque shields (e.g., thyroid collars, caps, etc.) may be packaged together, providing a system for preventing at least a portion of at least one individual's body from being exposed to ionizing radiation. In its most basic embodiment, such a system includes a package and a plurality of wearable radio-opaque shields. The package, which may include an interior configured to contain the plurality of wearable radio-opaque shields, at least temporarily holds the wearable radio-opaque shields together, and enables an individual to readily access one of the wearable radio-opaque shields for use.
The present invention also includes methods for using wearable radio-opaque shields. In such a method, a shield is placed on a portion of an individual's body, and remains in place while the individual is exposed to ionizing radiation. Once the individual is no longer exposed to ionizing radiation, the shield may be removed and stored for later re-use or it may be disposed. In embodiments where the radio-opaque material(s) of the shield is (are) non-toxic, disposal of the shield may simply include throwing it into a standard waste receptacle. A limited use shield may be used once before it is discarded, or it may be used multiple times during a predetermined period of time (e.g., a twenty-four hour period, a week, a month, etc.), then disposed of.
In another aspect, the present invention includes elements that reduce soiling of radio-opaque shields, whether wearable or not, including limited use shields. One embodiment of such an element is a finer configured for disposal between the shield and an individual on whom the shield is to be used (e.g., an individual who wears the shield, an individual over which a radio-opaque drape is placed, etc.). A liner my cover all or part of a single, inner surface (e,g., a surface configured to face an individual, a surface that may be exposed to contaminants, etc.) of a shield. Alternatively, a liner may be configured to cover more than one surface of a shield (e.g., wrap around edges of the shield, encase the shield, etc.). In embodiments where the shield is configured to be worn by or placed on an individual, a liner configured for use with the shield may be configured to absorb oil, perspiration, dirt and other soiling agents from the individual's body, and to prevent such soiling agents from adsorbing to a radio-opaque shield worn by the individual. Thus, a liner may increase the cleanliness of a shield, improving hygiene, and extend the useful life of the shield.
The configuration of a liner may enable its assembly with a radio-opaque shield and its disassembly from the shield. In some embodiments, a liner may have substantially the same configuration as that of an interior surface of the shield with the liner is intended to be used. A reusable embodiment of a liner may be configured for cleaning i.e, it may be reusable), while a disposable liner my be configured to be used once, or it may be configured for limited use (e.g., until the liner becomes visibly soiled; until an individual using the liner and the radio-opaque shield decides to clean or replace the liner, etc.).
Limited use liners may be provided to medical professionals or packaged together, like tissue or surgical gloves. In either embodiment, a liner may be provided in a package. The package may be configured to contain the liner or liners, and to enable an individual to readily access the liner for use.
In using a liner, a radio-opaque shield is oriented in such a way that a surface that is to be lined is exposed. A liner that corresponds to (e.g., is configured for use with) the shield may be oriented to substantially align with the shield, the liner is assembled with the shield, and the liner may be secured to the shield. The liner and shield may be aligned with, assembled with and, optionally, secured to one another in series or at substantially the same time. A liner may remain in place on its corresponding shield until its removal and disposal are desired. Removal may include detachment and disassembly of the liner from the shield.
Other aspects, as well as features and advantages of various aspects, of the present invention will become apparent to those of ordinary skill in the art through consideration of the ensuing description, the accompanying drawings and the appended claims.
In the drawings:
The present invention includes wearable radio-opaque shields, or radiation attenuating shields. A wearable radio-opaque shield that incorporates teachings of the present invention is configured to be worn by an individual during exposure to ionizing radiation. In various embodiments, wearable radio-opaque shields may be configured to be worn on or over certain body parts, attenuating ionizing radiation to which such body parts may otherwise be exposed.
Specific embodiments of wearable radio-opaque shields include, but are not limited to, thyroid collars, caps and ionizing radiation-attenuating garments designed to be worn by an individual (e.g., a healthcare provider, such as a doctor, a physician's assistant, a nurse, a technician, etc.; security personnel; etc.) while the individual is exposed to ionizing radiation (e.g., during a medical procedure; in using x-ray scanners; etc.).
In
Without limiting the scope of the present invention, a wearable radio-opaque shield, such as a thyroid collar 10 or a cap 20, may comprise a radio-opaque sheet 30. The '611 Application discloses several embodiments of radio-opaque sheets that may be used to fabricate all or part of a wearable radio-opaque shield of the present invention.
The radio-opaque sheet 30 may include a radio-opaque layer 35 carried by a substrate 40, as illustrated by
In some embodiments, the containment layers 42 and 46 may be configured in such a way as to enable folding of the radio-opaque sheet 30 of which they are a part. A variety of factors may enable folding of a radio-opaque sheet 30, including, without limitation, the material or Materials from which various elements (eg., the containment layers 42 and 46, etc.) of the radio-opaque sheet 30 are formed, as well as the thickness of various features (e.g,, the containment layers 42 and 46, etc.) of the radio-opaque sheet 30.
A variety of different materials are suitable for use as containment layers 42, 46, including, without limitation, polymers, papers, and fabrics. The material used as each containment layer 42, 46 may be selected on the basis of a number of factors, including, without limitation, the porosity of the material, water-resistance (which may be a function of porosity, the material itself, etc.), bacterial resistance (which may be a fnction of porosity, incorporation of antibacterial agents into the material, etc.), flexibility, feel, and any other factors. One or both of the containment layers 42 and 46 may attenuate ionizing radiation.
In some embodiments, each containment layer may comprise a polymer or a polymer-based material, More specifically, one or both containment layers 42, 46 may comprise a polymer film or a sheet of woven or non woven polymer fibers with paper-like or fabric-like characteristics. In other embodiments, one or both containment layers 42, 46 may comprise a polymer, but have a structure (e.g., fibers arranged in a way) that resembles paper or fabric.
By way of example, and not by way of limitation, each containment layer 42, 46 may have a thickness of about 15 mils (0.015 inch, or about 0.375 mm) or less. Of course, embodiments of radio-opaque sheets 30 that include containment layers 42, 46 of other thicknesses are also within the scope of the present invention.
In some embodiments, one or both containment layers 42 and 46 may include at least one surface 43, 47 with features 50, such as patterned or random texturing. Such features 50 may increase the effective surface area of the surface 43, 47 that carries the features 50 (e.g, the interior, or opposed, surfaces of the containment layers 42 and 46 depicted by
The radio-opaque layer 35 of such a radio-opaque sheet 30 includes a radio-opaque material 36, which attenuates at least some frequencies (or wavelengths) of ionizing radiation. In some embodiments, the radio-opaque material 36 of the radio-opaque layer 35 may be in a particulate or powdered form. In such embodiments, the radio-opaque layer 35 may include a binder 37 that holds particles of the radio-opaque material 36 together.
As indicated previously herein, the radio-opaque material 36 may be non-toxic. In various embodiments, the radio-opaque material 36 may comprise or be based upon elemental species having atomic numbers of or greater than 52. Non-limiting examples of such elemental species include barium species, bismuth species and lanthanum species. in some embodiments, the radio-opaque material 36 may comprise an inorganic salt. Non-limiting examples of non-toxic, radio-opaque inorganic salts include barium sulfate and bismuth oxide.
In embodiments where the radio-opaque layer 35 includes a binder 37, any material that will hold particles of the radio-opaque material 36 together without causing a substantial decrease in the density of the radio-opaque material 36 or an undesirable decrease in the ability of the radio-opaque material 36 to attenuate ionizing radiation may be used as the binder 37. The binder 37 may hold particles of radio-opaque material 36 together loosely, it may provide a stronger bond between adjacent particles, andlor it may enable the formation of a smooth uniform coating, a film or a foam. Examples of such materials include, but are not limited to, polyvinyl alcohol (PVA), polyvinyl hutyrol (PVB), polyethylene glycol (PEG), glycerine, capric triglyceride, cetyl alcohol, glyceryl sterate and combinations of any of these materials.
In a radio-opaque layer 35 in which particles of radio-opaque material 36 are held together with a binder 37, the radio-opaque material 36 may, in some mbodiments, comprise at least about 50% of the weight of the radio-opaque layer 35, with the binder 37 comprising about 50% or less of the weight of the radio-opaque layer 35. Other embodiments of radio-opaque layers 35 include about 75% or more of the radio-opaque material 36, by weight, and about 25% or less of the binder 37, by weight. In still other embodiments, the radio-opaque material 36 may comprise about 97% or more of the weight of the radio-opaque layer 35, while the binder 37 comprises only up to about 3% of the weight of the radio-opaque layer 35.
In some embodiments, a radio-opaque layer 35 of a radio-opaque sheet 30 of the present invention has a thickness of about 40 mils (0.040 inch, or 1 mm) or less. In other embodiments, a radio-opaque sheet 30 may include a radio-opaque layer 35 with a thickness of about 25 mils (0.020 inch, or about 0.6 mm) or less. In still other embodiments, the radio-opaque layer 35 of a radio-opaque sheet 30 may have a thickness of about mils (0.015 inch, or about 0.375 mm) or less, about mils (0.010 inch, or about 0.25 mm) or less, or about 5 mils (0.005 inch, or about 0.125 mm) or less.
The ability of the radio-opaque layer 35 to attenuate ionizing radiation depends upon a number of actors, including, without limitation, the attenuating ability of each radio-opaque material 36 from which the radio-opaque layer 35 is formed, the relative amounts of radio-opaque material 36 and binder 37 in the radio-opaque layer 35, and the thickness of the radio-opaque layer 35.
The containment layers 42, 46 may be secured to the radio-opaque layer 35, and to one another, in a number of different ways. As an example, in embodiments where the radio-opaque layer 35 includes a particulate or powdered radio-opaque material 36 and a binder 37, the binder 37 may adhere or otherwise secure the containment layers 42, 46 to the radio-opaque layer 35 and, thus, to one another. In other embodiments, the containment layers 42, 46 may be directly or indirectly secured to one another at a plurality of spaced apart locations 49 (e.g, in a matrix of spaced apart points, a grid of spaced apart row tines and column etc.), as shown in
Known processes may be used to manufacture a radio-opaque sheet 30. In some embodiments, the radio-opaque material 36 and binder 37 may substantially homogeneously mixed in a solvent. The solvent may comprise a carrier solvent within which the binder 37 is provided, or a separately added solvent. more specific mbodiments, the resulting slurry may have a solids content, or solids loading, of about 75% wriw to about 80% W/W. The slurry may then be applied to one of the containment layers 42 in a manner that will result in the formation of a thin film or a foam comprising the radio-opaque layer 35 over the containment layer 42. In specific embodiments, a doctor blade or simulated doctor blade technique may be employed to form the radio-opaque layer 35. The other containment layer 46 may then be applied over the radio-opaque layer 35. In other embodiments, one or more rollers may be employed to form and disperse the radio-opaque layer 35 between the containment layers 42, 46. In a specific embodiment suitable for mass production, roll calendaring techniques may be used.
In addition to the radio-opaque sheet 30, a wearable radio-opaque shield (e.g., a thyroid collar 10 such as that shown in
A wearable radio-opaque shield (e.g., a thyroid collar 10 such as that shown in
In some embodiments of a fabrication method, these processes may completely define a wearable radio-opaque shield. In other embodiments, the element or elements that have been defined from a radio-opaque sheet 30 may be assembled with other elements of a wearable radio-opaque shield, such as an outer shell 32, fasteners, a garment or garment features, or the like. Assembly of the radio-opaque portion of a wearable radio-opaque shield with other features of the shield may include the use of thermal bonding processes, adhesives, sewing or any other suitable technique.
Wearable radio-opaque shields that incorporate teachings of the present invention may be made available in a plurality of different sizes, enabling selection of a size appropriate for the individual on which the wearable radio-opaque shield is to be used. some embodiments, the shape and or size of a wearable radio-opaque shield may altered (e.g., by cutting, etc.) just prior to placing it on an individual to tailor it to that individual.
As an example of the use of a wearable radio-opaque shield (e.g., a thyroid collar 10 such as that shown in
Referring now to
The wearable radio-opaque shields 70 of the package 60 may be disposable or intended for limited use. The package 60 may include means for helping an individual user understand that the wearable radio-opaque shields 40 are intended for limited use (e.g., to be disposed of after a single use, a certain period of time, or when their use is no longer desired by the individual, etc.). Such means may include the availability of additional wearable radio-opaque shields 70 within the interior 64 of the container 62, instructions provided with the package 60 (e.g, on the container 62, etc.), or the like.
In some embodiments, all of the wearable radio-opaque shields 70 of the package 60 may be of the same type as one another. For example, all of the radiation shields 70 may comprise thyroid collars 10 (
Turning now to
In various embodiments, and as illustrated by
A liner 80 may also prevent or minimize soiling of a radio-opaque shield 70′ by absorbing contaminants from the skin of the individual with whom the radio-opaque shield 70′ is used, Thus, the liner 80, or at least a portion of the liner 80, may include an absorbent layer 82 of a suitable absorbent material. Various embodiments of such a material include, but are not limited to, natural fabrics e.g., cotton, etc.), fabrics including synthetic materials (e.g, fleece, so-called “microfiber” wicking materials, etc.), absorbent papers, absorbent paper-like materials (e.g., paper-like materials formed from polymer fibers, etc.), and the like.
The absorbent layer 82 may be carried by (e.g., laminated with, coated with, etc.) a barrier film 84, which may prevent contaminants from passing through absorbent layer 82 to the radio-opaque shield 70′. Accordingly, the barrier film 84 may comprise a substantially non-porous polymer that will provide a barrier that is both water resistant and oil resistant, and that will withstand salts and other contaminants that may be present on an individual's skin.
An attachment element 86 of the liner 80 may be configured to secure the liner 80 to a radio-opaque shield 70′. In a specific embodiment, the attachment element 86 may comprise a low-tack, reusable, pressure-sensitive adhesive, which enables release of the liner 80 from a surface, and its subsequent adhesion to the same or another surface. Of course, the attachment element may alternatively include other embodiments of attachment elements (e,g,, hook and/or loop-type fasteners, etc.).
When assembly of the liner 80 with a radio-opaque shield 70′ is desired, the liner 80 may be aligned with a portion of the radio-opaque shield 70′ that the liner 80 is intended to cover, and assembled with the radio-opaque shield 70′, The liner 80 may be secured to that portion of the radio-opaque shield 70′. In some embodiments, the acts of alignment, assembly, and securing may be effected substantially concurrently with one another.
Once a liner 80 has been visibly soiled, or replacement of the liner 80 is otherwise desired, the liner 80 may be removed from the radio-opaque shield 70′, as depicted by
Turning now to FIG, 7, a plurality of liners 80 may be packaged together. In embodiments where liners 80 include attachment elements 86 (
Although the foregoing description contains many specifics, these should not be construed as limiting the scope of the invention or of any of the appended claims, but merely as providing information pertinent to some specific embodiments that may fall within the scopes of the invention and the appended claims, Other embodiments of the invention may also be dcvised which lie within the scopes of the invention and the appended claims. Features from different embodiments may be employed in combination. The scope of the invention is, therefore, indicated and limited only by the appended claims and their legal equivalents. All additions, deletions and modifications to the invention, as disclosed herein, that fall within the meaning and scopes of the claims are to be embraced thereby.
This application is a non-provisionat of U.S. Provisional Patent Application No. 61/469,783 titled “Disposable Radiation Attenuating Garments,” filed Mar. 30, 2011, pending (the “'783 Application”). A claim for the benefit of priority to the '783 Application is hereby made pursuant to 35 U.S.C. §119(e). This application is also related to U.S. patent application Ser. No. 13/421,961 filed Mar. 16, 2012. The entire disclosure of each of the foregoing applications is, by this reference, hereby incorporated herein.
| Number | Date | Country | |
|---|---|---|---|
| 61469783 | Mar 2011 | US |
