Patent Application
20080139944
The present invention relates generally to ultrasound imaging. More particularly, the invention relates to devices and methods for covering ultrasound probes of ultrasound machines, and acoustically coupling the ultrasound probes to body surfaces of a patient.
Ultrasound images are typically generated by placing an ultrasound probe of an ultrasound machine in contact with a body surface of a patient, and directing high-frequency acoustical energy at the body surface. The ultrasound probe senses the acoustical energy reflected from the body surface and the underlying portion of the patient's body. The reflected energy is converted to an electrical signal by the ultrasound probe. The signal is relayed to a processing and display unit of the ultrasound machine, where the signal is transformed into an image. The signal can be relayed by a cable connected to the ultrasound probe and the ultrasound machine, or by wireless means such as radio frequency (RF) transmission.
A water-based gel, commonly referred to as ultrasonic gel, is commonly used to facilitate transmission of acoustical energy between the ultrasound probe and the body surface. The ultrasonic gel facilitates transmission of acoustical energy by substantially eliminating gaps or pockets of air between the ultrasound probe and the body surface. Ultrasonic gel for use in sterile applications is usually supplied in a sealed packet that maintains the ultrasonic gel in a sterile condition prior to use.
Ultrasound procedures are often performed in a sterile environment. As the non-sterile ultrasound probe needs to be pressed against the body surface of the patient to obtain a satisfactory ultrasound image, the non-sterile ultrasound probe is typically covered with a sheath formed from a flexible, sterilizable, fluid-impermeable material such as latex, polyethylene, polyurethane, or other polymeric materials. Sterile ultrasonic gel is usually applied to the body surface, and to the interior surface of the sheath against which the ultrasound probe is pressed, to facilitate transmission of acoustical energy between the ultrasound probe and the body surface.
The ultrasonic gel within the sheath usually spreads beyond the sensing face of the ultrasound probe and covers other portions of the probe, due to the manipulation of the probe during the ultrasound procedure. In applications where a wired ultrasound probe is used, the ultrasonic gel may also spread to and cover the portion of the cable proximate the probe.
The relatively thick and slippery ultrasonic gel needs to be removed from the ultrasound probe (and its cable, if applicable) after the ultrasound procedure has been completed and before the next use of the ultrasound probe. Moreover, the body surface of the patient needs to be cleansed of the ultrasonic gel. The expenditures of time and effort associated with applying and removing the ultrasonic gel before and after the ultrasound procedure can adversely impact the workflow efficiency of the technician performing the procedure. Applying and removing the ultrasonic gel can cause patient discomfort when the body surface is sensitive from an injury, a surgical procedure, etc. Moreover, ultrasonic gel can spread into unwanted areas once applied.
Adequate supplies of sterile ultrasonic gel, and sterile wipes for the clean-up process need to be maintained during the ultrasound procedure, when the procedure is performed under sterile conditions. Also, the quality of the ultrasound image can be adversely affected when an excessive amount of ultrasonic gel is applied to the interior of the sheath or the body surface of the patient.
Applying the sheath to the ultrasound probe usually requires two individuals. In particular, a first individual who is properly prepped for a sterile environment is located within the sterile field, and holds the sheath at or near the perimeter of the sterile field. The first individual, and/or a second individual located outside of the sterile field apply sterile ultrasonic gel to the inside of the sheath. The second individual then places the non-sterile ultrasound probe inside the sheath without touching the exterior of the sheath. The first individual then closes and secures the open end of the sheath without touching the interior of the sheath or the ultrasound probe.
An ongoing need thus exists for devices and methods for acoustically coupling an ultrasound probe of an ultrasound machine with a body surface of a patient without the use of ultrasonic gel, while maintaining a sterile barrier between the ultrasound probe and the body surface.
Preferred embodiments of devices for covering an ultrasound probe can include a membrane, such as a sheath, having one or more ultrasonic couplers attached thereto for transferring ultrasonic energy between the ultrasound probe and a body surface of a patient.
Preferred embodiments of devices for covering an ultrasound probe that generates and receives acoustical energy are provided. The devices can comprise a sheath that receives the ultrasound probe and is capable of forming a barrier between the ultrasound probe and a body surface toward which the acoustical energy is directed. The devices can also comprise an ultrasonic coupler attached to the sheath and capable of transferring the acoustical energy between the ultrasound probe and the body surface.
Preferred embodiments of devices for transferring acoustical energy comprise a membrane, and a first ultrasonic coupler in contact with a first side of the membrane. The devices also comprise a second ultrasonic coupler in contact with a second side of the membrane and aligned with the first ultrasonic coupler whereby the acoustical energy can be transferred between the first and second ultrasonic couplers by way of the membrane.
Preferred methods are provided for acoustically coupling an ultrasound probe and a body surface comprise inserting the ultrasound probe into a sheath, urging a sensing face of the ultrasound probe against an ultrasonic coupler attached to a sheath, and directing the ultrasonic energy though the ultrasonic coupler.
Preferred methods for preparing an ultrasound probe for use comprise covering a portion of the ultrasound probe with a sheath while the ultrasound probe is positioned on a device that holds the ultrasound probe, and grasping the portion of the ultrasound probe covered by the sheath. The methods also comprise lifting the probe from the device that holds the ultrasound probe, covering a remainder of the ultrasound probe with the sheath; and closing an open end of the sheath.
Preferred embodiments of devices for covering an ultrasound probe comprise a sheath that receives the ultrasound probe, a layer of ultrasonic gel disposed on an interior surface of the sheath, and a cover positioned over the ultrasonic gel and sealed to the interior surface of the sheath.
Preferred processes for supplying ultrasound probes for use in ultrasound procedures comprise providing the ultrasound probes to a user. Each of the ultrasound probes is packaged in a sheath that can form a fluid-impermeable barrier between the ultrasound probe and a body surface of a patient, and a sealed package that covers the sheath and the ultrasound probe and forms a barrier around the sheath and the ultrasound probe.
The processes also comprise receiving the ultrasound probes from the user after the ultrasound probes have been used in the ultrasound procedures, repackaging the ultrasound probes in new ones of the sheaths and the packages, and supplying the repackaged ultrasound probes to the user.
The foregoing summary, as well as the following detailed description of a preferred embodiment, are better understood when read in conjunction with the appended diagrammatic drawings. For the purpose of illustrating the invention, the drawings show an embodiment that is presently preferred. The invention is not limited, however, to the specific instrumentalities disclosed in the drawings. In the drawings:
The sheath 12 receives the ultrasound probe 20, as shown in
The use of the device 10 in conjunction with a wireless ultrasound probe is disclosed for exemplary purposes only. The device 10, and alternative embodiments thereof, can be used in conjunction with wired ultrasound probes.
The sheath 12 has an open end 12a that receives the ultrasound probe 20, as shown in
In applications where the device 10 is used with a wired probe, the sheath 12 can be elongated so that the sheath 12 receives the entire wired probe, and a proximal portion of the probe's cable. The sheath 12 can include provisions, such as the above-mentioned drawstring 30 or adhesive bands, that permit the end 12a to be drawn around and secured to the wire.
The ultrasound probe 20 may be used in sterile environments. The sheath 12 therefore needs to function as a sterile barrier between the ultrasound probe 12, and the sterile environment. Accordingly, the sheath 12 should be formed from a flexible, sterilizable, fluid-impermeable material such as latex, polyethylene, polyurethane, or other suitable materials.
The first ultrasonic coupler 14 is attached to an interior, or inwardly-facing surface of the sheath 12. The second ultrasonic coupler 16 is attached to an exterior, or outwardly-facing surface of the sheath 12. The first and second ultrasonic couplers 14, 16 are aligned with each other as depicted in
The second ultrasonic coupler 16 can be positioned on a body surface 25 on the patient, and the sensing face 20a can be pressed against the first ultrasonic coupler 14 after the ultrasound transducer 20 has been placed in the sheath 12, as shown in
Each of the first and second ultrasonic couplers 14, 16 can comprise, for example, a pad 23 formed from a layer of cellulose material. The cellulose material can be impregnated with a mixture of glycerin and water.
Preferably, the outer periphery of each pad 23 is not impregnated with the mixture of glycerin and water. Adhesive can be applied to the outer periphery to secure the first or the second ultrasonic coupler 14, 16 to the sheath 12. The outer dimensions of each pad 23 are preferably greater than the outer dimensions of the sensing face 20a of the ultrasound probe 20, as shown in
The first and second ultrasonic couplers 14, 16 can be attached to the sheath 12 by means other than adhesive in alternative embodiments. For example, the first and second ultrasonic couplers 14, 16 can each include a frame 17 (depicted in phantom in
Specific details of the first and second ultrasonic couplers 14, 16 are provided for exemplary purposes only. Other types of ultrasonic couplers can be used in the alternative. For example, alternative embodiments of the first and second ultrasonic couplers 12, 14 can be formed from a gelled material, a part of which is hardened to facilitate attachment to the sheath 12. The gelled material can include, for example, a water-soluble polymeric compound that has been cross-linked by exposure to radiation or one or more freeze cycles. The polymeric compound can be polyvinyl alcohol, polyethylene oxide, polyacrylamide, or similar materials. A frame, such as the above-described frame 17, can be can be embedded in the hardened portion of the gelled material as the ultrasonic coupler is molded.
Other alternative embodiments of the first and second ultrasonic couplers 14, 16 can be formed as a sheet including a solid phase comprising a natural or synthetic hydrophilic block co-polymer and approximately 20 percent to approximately 95 percent by weight biocompatible liquid. For example, the first and second ultrasonic couplers 14, 16 can comprise a hydrophilic block co-polymer and greater than 70 percent by weight water or saline to form a flexible, solid hydrogel matrix. Other alternative embodiments of the first and second ultrasonic couplers 14, 16 can be formed, for example, from polyvinyl alcohol in combination with polyvinylpyrolidone, polyethylene glycols, and water.
The second ultrasonic coupler 16 should be sterile when the device 10 is used in a sterile application. The second ultrasonic coupler 16 does not need to be a sterile barrier, however, because the non-sterile ultrasound probe 20 is isolated from the sterile field and the body surface 25 by the sheath 12. The first ultrasonic coupler 14 does not have to be sterile when the device 10 is used in a sterile application, because the sheath 12 isolates the first ultrasonic coupler 14 from the sterile field and the body surface 25.
Preferably, the first and second ultrasonic couplers 14, 16 are each equipped with a cover 28. The covers 28 are shown only in
The outer edges of each cover 28 are sealed to an underlying portion of the sheath 12 by a suitable means, such as a relatively weak adhesive, that permits the cover 28 to be removed by the user without damaging the sheath 12. Each cover 28 is preferably formed from a flexible, sterilizable, fluid-impermeable material that maintains the associated first or second ultrasonic coupler 14, 16 in a sterile condition, and prevents the first or second ultrasonic coupler 14, 16 from drying out prior to use. For example, each cover 28 can be formed from as a sheet of aluminum-alloy foil.
The device 10 can include a strap 33 attached to the sheath 12, as shown in
The device 10 can facilitate the transmission of ultrasonic energy between an ultrasound probe, such as the ultrasound probe 20, and the body surface 25 on a patient without the use of ultrasonic gel. The use of the device 10 can thus improve workflow efficiency by eliminating the expenditures of time and effort associated with applying the ultrasonic gel to the body surface 25 and the ultrasound probe 20 before the ultrasound procedure, and cleaning the ultrasonic gel from the patient and the ultrasound probe 20 (and the cable of a wired ultrasound probe) after the procedure. Moreover, patient discomfort caused by applying and removing the ultrasonic gel to and from an injured or otherwise sensitive area can be eliminated through the use of the device 10.
A supply of sterile ultrasonic gel, and an supply of sterile wipes for clean-up do not need to be maintained when the device 10 is used in lieu of the ultrasonic gel. Also, the potential for degradation of the ultrasound image caused by applying a layer of ultrasonic gel that is too thick or too thin can be eliminated through the use of the device 10.
The device 10, and alternative embodiments thereof, can be installed on the ultrasound probe 20 by a single user in preparation for use in a sterile application, as follows. The user, properly prepped for the sterile-field environment, removes the device 10 from a sealed package or wrapping that maintains the device 10 in a sterile condition prior to use. The non-sterile ultrasound probe 20 is pre-positioned on a stand or other suitable holding device, with the sensing face 20a preferably facing generally upward and with most of the body 20b of the ultrasound probe 20 exposed. The stand can be located outside of the sterile field.
The user removes the cover 28 on the first ultrasonic coupler 14. The user then slides the sheath 12 over the sensing face 20a and a portion of the body 20b of the ultrasound probe 20, so that the first ultrasonic coupler contacts the sensing face 20a. The sheath 12 should be slid over the ultrasound probe 20 by the user using one or both hands held over the outside of the sheath 12, to avoid touching the non-sterile ultrasound probe 20.
The user can grasp the ultrasound probe 20 around the portion of the sheath 12 installed over the ultrasound probe 20 using one hand. The user can then lift and remove the ultrasound probe 20 from the stand. The user can pull the sheath 12 over the remainder of the ultrasound probe 12 using the other hand, once the ultrasound probe 20 is free of the stand. The end 12a of the sheath 12 can then be secured using the drawstring 30 or other closing means, so that the sheath 12 completely encloses the ultrasound probe 20. (In embodiments where the ultrasound probe is a wired probe, the sheath 12 can be extended up the probe's cable.) The cover 28 on the second ultrasonic coupler 16 can be removed to place the ultrasound probe 20 and the device 10 in a ready-to-use condition. The user can thus install the device 10 on the non-sterile ultrasound probe 20 while remaining isolated from the ultrasound probe 20, and without assistance from another individual.
Wireless ultrasound probes such as the ultrasound probe 20 can be supplied to a health care provider already covered in the device 10 or alternative embodiments thereof, in a condition ready for use in an ultrasound procedure. The device 10 and the enclosed ultrasound probe 20 can be placed in a hermetically-sealed package that acts as a fluid-impermeable barrier, to maintain the exterior surfaces of the device 10 in a sterile condition prior to use. After use, the device 10 can be discarded, and the ultrasound probe 20 can be returned to the supplier for repackaging in a new device 10. Alternatively, a hospital, clinic, doctor's office, or like establishment can establish internal facilities and processes for packaging devices 10 and ultrasound probes 20 in hermetically-sealed packages, and providing the ready-to-use devices 10 and ultrasound probes 20 to operators at the hospital, clinic, or doctor's office.
The supplier can maintain ownership of the ultrasound probes 20. The supplier can supply the pre-packaged ultrasound probes 20 on a pre-arranged schedule, upon return of the used ultrasound probes 20, or in accordance with other arrangements between the supplier and the user. A predetermined fee can be charged to the user for each time an ultrasound probe is provided by the supplier. Other payment arrangements, such as a fixed fee for a predetermined number of pre-packaged ultrasound probes 20, can be used in the alternative.
The foregoing description is provided for the purpose of explanation and is not to be construed as limiting the invention. Although the invention has been described with reference to preferred embodiments or preferred methods, it is understood that the words which have been used herein are words of description and illustration, rather than words of limitation. Furthermore, although the invention has been described herein with reference to particular structure, methods, and embodiments, the invention is not intended to be limited to the particulars disclosed herein, as the invention extends to all structures, methods and uses that are within the scope of the appended claims. Those skilled in the relevant art, having the benefit of the teachings of this specification, may effect numerous modifications to the invention as described herein, and changes may be made without departing from the scope and spirit of the invention as defined by the appended claims.
Alternative embodiments of device 10 can include a single ultrasonic coupler. For example,
The outer edges of the ultrasonic coupler 40 can be sealed to the overlapping surfaces of the sheath 38 by a suitable means such as adhesive. Alternatively, the outer edges can have a plastic piece or pieces attached thereto or embedded therein, as described above in relation to the first and second ultrasonic couplers 14, 16. The plastic piece or pieces can be sealed to the overlapping surfaces of the sheath 38 by glue, a heat seal, or other suitable means. The seal needs to be continuous, to maintain a sterile barrier between the non-sterile ultrasound probe 20 and the body surface 25 during use.
A cover, such as the cover 28 of the device 10, can be positioned over each side of the ultrasonic coupler 40. The cover 28 is not shown in
In use, the transducer 20 is placed in the sheath 38 by way of an open end 38a thereof, after the cover 28 positioned on the inwardly-facing side of the ultrasonic coupler 40 has been removed by the user. The open end 38a can be closed and secured as described above in relation to the sheath 12. The cover 28 positioned on the outwardly-facing side of the ultrasonic coupler 40 can be removed to place the ultrasound probe 20 and the device 10a in a ready-to-use condition.
The sensing face 20a of the ultrasound probe 20 can be pressed against the inwardly-facing surface of the ultrasonic coupler 40, and the outwardly-facing surface of the ultrasonic coupler 40 can be placed against the body surface 25 of the patient. Ultrasonic energy can then be transferred between the sensing face 20a and the body surface 25 by way of the ultrasonic coupler 40.
The ultrasonic coupler 40 should act as a sterile barrier when the device 10 is used in a sterile application, as the ultrasonic coupler 40 is the only structure between the ultrasound probe 20 and the body surface 25. Accordingly, the ultrasonic coupler 40 should be formed from at least one layer of solid, fluid-impermeable material when the device 10a is to be used in a sterile application. For example, the ultrasonic coupler 40 can be formed from a water-soluble polymeric compound that has been cross-linked by radiation. The polymeric compound can be polyvinyl alcohol, polyethylene oxide, polyacrylamide, or similar materials.
The device 10b further comprises a cover 52 positioned over the layer of ultrasonic gel 50. The outer edge of the cover 52 can be sealed to an underlying portion of the sheath 12 by a suitable means, such as a relatively weak adhesive, that permits the cover 52 to be removed by the user without damaging the sheath 12. The cover 52 is not depicted in
The cover 52 can be removed from the sheath 12 to expose the ultrasonic gel 50, prior to insertion of the ultrasound probe 20 in the sheath 12. Alternatively, the cover 52 can be configured with a weakened area formed by score lines 54, perforations, or other suitable means, as shown in
The use of the device 10b does not eliminate the need to clean ultrasonic gel from the ultrasound probe 20 or the body surface 25 after the ultrasound procedure. The time and effort associated with applying ultrasonic gel to the interior surface of the sheath 12, however, can be eliminated through the use of the device 10b.
