Patent Application
20080208083
All publications and patent applications mentioned in this specification are herein incorporated by reference to the same extent as if each individual publication or patent application was specifically and individually indicated to be incorporated by reference.
The invention is in the field of medical devices related to urogenital health, more particularly to devices that dwell in the urinary tract.
The urinary tract extends from the collecting tubules in the kidney where urine is excreted from the nephrons to the meatus of the urethra where the urine exits the body. Many devices in contact with the urinary tract are subject to a problematic deposition of biomaterials from the urinary tract environment. The devices can readily become a nidus for stone formation or encrustation from soluble elements that precipitate and accumulate on the surface of such devices. Such accumulated deposition can occur on the inner luminal surface of devices, even to the extent of occluding them, and on the outer surface, creating pain and complications, such as the inability to remove the device. Formation of such encrustration is very common, if not nearly inevitable with sufficient time, on devices situated in the urinary tract. Similarly, although with less frequency, clots or thrombi can form around devices in the urinary tract.
A variety of indwelling medical devices are used to either treat conditions or to functionally substitute for portions of the urinary tract along its entire length, from the kidney to the urethral opening. Common urinary devices in men and women include ureteral stents for treating obstruction of the ureter, ureteric fistulas, and gaps or defects caused by trauma or other conditions, and incontinence devices for treating the lack of control of micturition and incontinence. Foley catheters are used for dealing variously with controlling continence, urinary tract obstruction, and sphincter restriction of flow following anesthesia. In men, devices further include urethral catheters for treating benign or cancerous prostate growth, urethral strictures, and incontinence, and penile prosthetics for treating erectile dysfunction. In some cases, these devices are inserted for relatively short duration, but in the case of indwelling stents, they are typically used for much longer periods of time, and are typically changed every three to six months to prevent clinically problematic encrustation.
Long term urethral catherization for intractable urinary incontinence or retention is particularly common among patients in chronic care facilities, and a large portion of these patients experience catheter blockage. Such blockage generally can cause pain, and incontinence to due urine bypassing the catheter, and is associated with uriny tract infections. Encrustation even without blockage can cause pain, and can severely complicate the process of changing cathethers. The removal of an indwelling stent that has become encrusted can turn a normally minor procedure into a highly involved and difficult one, placeing the patient at risk of unexpected complications and also the need for costly and time consuming surgical procedures. The clinical significance of encrusted stents is serious and well known, as reported for example, by Singh et al. (Severely encrusted polyurethane ureteral stents: management and analysis of potential risk factors. Urology 58 (4) 526-531, 2001). Bultitude et al. (Management of encrusted ureteral stents impacted in upper tract. Urology 62 (4) 622-626, 2003.), and Park et al. (Clinical features determining the fate of a long-term, indwelling, forgotten double J stents. Urol. Research 32: 416420, 2004).
Bacterial infection can be associated with encrustation either as a contributing cause or as a complication. Several patents have described approaches to mitigating encrustation by way of incorporating coatings on indwelling urinary devices that provide a level of bacterial resistance or resistance to adhesion of foreign materials, such as U.S. Pat. No. 5,328,954, U.S. Pat. No. 5,877,243, and U.S. Pat. No. 5,935,094. Encrustation and the deposition of materials on devices in the urinary, however, involves the basic processes that underlie urinary stone formation even without the causes or complications associated with infection. The problem of deposition of material on indwelling urinary tract devices remains very prevalent, and is in need of new and more effective preventative and interventional approaches.
The invention relates to material deposition-countering urinary tract device that includes a structure adapted to dwell at least partially in the urinary tract and an actuator operably coupled to the structure such that actuator activation induces motion of the structure. Embodiments of these indwelling device may include any of a ureteral stent, an upper urinary tract stent, a lower urinary tract stent, a catheter, a urethral prosthesis, a urethral insert, an artificial urinary sphincter, a nephrostomy tube, a suprapubic tube, a urethral plug, or any structure adapted to dwell within the urinary tract. The device embodiments may dwell in any portion of the urinary tract, including any one or more portions of a kidney, a ureter, a bladder, or a urethra. Embodiments of the device include a surface with an area, and the induced motion includes a transient reconfiguration of the surface area.
The actuator included in embodiments of the device may include any of a motor, a mechanical transducer, a piezoelectric element, a shape memory polymer, an electroactive polymer, a shape memory alloy, a miniature actuator, an electromechanical actuator, or an electromagnetic actuator. Embodiments of the device may be configured to receive energy conveyed by a physical connection, or they may be configured to receive wireless energy. In some embodiments, the device is further configured to focus received wireless energy. In particular embodiments the received energy is ultrasonic energy.
In some embodiments, the motion-inducing actuator and the structure of the device are structurally integrated, in other embodiments, though being operably connected, they are not structurally integrated.
In some embodiments, the motion-inducing actuator includes a mechanical transducer powered by a physiological process. In some of these embodiments, the physiological process includes urine flow, and the mechanical transducer includes a fluid-flow energy transducer in the urine flow path.
In some embodiments, the device further includes an energy source to power the motion-inducing actuator. In some of these embodiments, the energy source is physically connected to the actuator, for example, an energy storage device, such as a battery or a capacitor. In other embodiments, the device is configured to deliver energy wirelessly. In some of these embodiments, the wireless energy source may be any of an inductive coil, a microwave emitter, a radiofrequency emitter, or a sonic emitter. Some embodiments of the wireless energy source are located external to the body, some of these may by attached to the body, or held in an article attached to the body, or worn by the patient. In other embodiments, the energy source is unattached to the patient. In still other embodiments, the energy source is implanted in the body.
Some embodiments of the device further include a wireless energy receiver configured to convey energy to the motion-inducing actuator. Various of these embodiments may include any of an antenna, a sonic transducer, or an electromagnetic-mechanical transducer.
Embodiments of the device may be subject to material deposition on any of an external surface of the device or an internal surface of the device, the device countering such material. In some embodiments, the deposition may include a precipitate of at least one solute from urine. Such solutes may include any one or more of calcium oxalate monohydrate, calcium oxalate dihydrate, calcium phosphate, magnesium ammonium phospate, struvite, hydroxyapatite, carbonate apatite, brushite, cystine, indinavir, triamterene or uric acid. In other embodiments, the deposition is of thrombotic origin. In still other embodiments, the deposition may include cellular material, such as any of whole cells, cell fragments, or cell-derived debris. In still other embodiments, the deposition may include a biologically-derived film or biofilm, such as a film derived from the patient or from an organism that has infected the patient or is naturally resident in the patient. In some instances the deposits may include medicines taken by the patient or metabolic products thereof that precipitate out in the urine.
The invention further relates to material deposition-countering urinary tract system that includes a device adapted to dwell at least partially in the urinary tract and an energy source adapted to provide energy to move the device. Embodiments of the device may include any of a ureteral stent, an upper urinary tract stent, a lower urinary tract stent, a catheter, a urethral prosthesis, a urethral insert, an artificial urinary sphincter, a nephrostomy tube, a suprapubic tube, a urethral plug, or any structure adapted to dwell within the urinary tract. The device may dwell in any portion of the urinary tract, including any one or more portions of a kidney, a ureter, a bladder, or a urethra. Embodiments of the device include a surface with an area, and in some embodiments, the induced motion induces a transient reconfiguration of the surface area.
In some embodiments of the system, the device is adapted to focus received wireless energy, such as, for example, ultrasonic energy. In some of these embodiments, the adaptation includes an energy focusing element that moves in response to the energy, the element configured to impart movement to the device as a whole. In some embodiments, the energy focusing element is attached to the device, in other embodiments, energy focusing element is integral to the device. In still other embodiments, the adaptation includes the device having a composition with an elastic modulus different from that of a conventional device. In other embodiments, the adaptation includes the device having a physical form that supports a resonant standing wave.
In some embodiments of the system, the energy source is configured to provide energy by physical connection; in other embodiments the the energy source is configured to provide energy wirelessly. Embodiments of a wireless energy source include any of an inductive coil, a microwave emitter, a radiofrequency emitter, or an ultrasonic emitter.
In some embodiments of the system, the energy source may be included internally within the body; in other embodiments, the may be is external to the body. In embodiments, where the energy source is disposed external to the body, the energy source may be attached to the patient, including being held in an article attached to the body, or worn by the patient. In other embodiments, the energy source is unattached to the patient. In still other embodiments, the energy source is implanted in the body.
Embodiments of the system may be subject to material deposition on any of an external surface of the device or an internal surface of the device, the device countering such deposition of material. In some embodiments, the deposition may include a precipitate of at least one solute from urine. Such solutes may include any one or more of calcium oxalate monohydrate, calcium oxalate dihydrate, calcium phosphate, magnesium ammonium phospate, struvite, hydroxyapatite, carbonate apatite, brushite, cystine, indinavir, triamterene, or uric acid. In other embodiments, the deposition is of thrombotic origin. In still other embodiments, the deposition may include cellular material, such as any of whole cells, cell fragments, or cell-derived debris. In still other embodiments, the deposition may include a biologically-derived film or biofilm, such as a film derived from the patient or from an organism that has infected the patient or is naturally resident in the patient.
The invention further relates to a method of countering material deposition on a urinary tract system that includes a device adapted to dwell at least partially in the urinary tract and an energy source adapted to provide energy to move the device, the method includes moving the device. In some embodiments of the system, the system further includes an actuator operably coupled to the structure such that actuator activation induces motion of the device.
In some embodiments of the method, the energy source conveys energy to the motion-inducing actuator by a physical connection; in other embodiments, the energy source may configured to provide energy wirelessly.
In some embodiments, the energy source in configured to convey energy to the motion-inducing actuator. In other embodiments, the device further comprises an energy focusing element that moves in response to receiving energy, the element configured to then impart such movement to the device as a whole.
Embodiments of the method of moving the device include moving it sufficiently to counter the presence of material on the device. Countering the deposition may include any of impeding material deposition, preventing material deposition, diminishing an extant deposition of material, or clearing a device occluded by deposited material such that urine may flow through the structure.
Embodiments of the method of moving the device include moving the device translationally with resonance along any of linear or rotational degree of freedom, moving the device translationally without resonance along any of linear or rotational degree of freedom, or moving the device deformationally with modes of any order, along any of linear or rotational degrees of freedom, or any combination of such types of translational and deformational movement.
Embodiments of the method of moving the device include moving the device sufficiently to counter the presence of material deposition comprises moving the device for a sufficient amount of time. Moving for a sufficient amount of time may include any of sufficient total amount of time per day, a sufficient total amount of time per week, or a sufficient amount of time per month, or a sufficient period of time during the residence of the device. In some embodiments of the method, moving the device occurs episodically, in which instance a sufficient period of time may include moving the device for a sufficient amount of time per episode.
In other embodiments of the method, moving the device sufficiently to counter the presence of material deposition includes moving the device with sufficient power. In some embodiments, moving with sufficient power may include moving the device with a sweep of a range of power. In other embodiments, moving the device sufficiently to counter the presence of material deposition includes moving the device at an effective vibrational frequency. In some of these embodiments, moving at an effective vibrational frequency includes moving the device with a sweep through a range of frequencies.
The invention still further relates to a material deposition-countering bodily indwelling system that includes a device adapted to dwell at least partially in a space in the body and an energy source adapted to provide energy to move the device. In some embodiments, the system further includes an actuator operably coupled to the structure such that actuator activation induces motion of the device. In other embodiments, the device is configured with an adapative feature that focuses received energy, or includes an incorporated or attached element that focuses received energy. In some embodiments received energy causes heating in addition to or instead of movement. In some embodiments, the space in the body comprises a lumen, such as, by way of example, any of an auditory canal, a blood vessel, a heart, a bile duct, a salivary gland, a parotid gland, a sinus, or a lacrimal duct, or a pulmonary lumen. In other embodiments, the space in the body includes a cavity, such as, for example the pleural cavity or the peritoneal cavity. In still other embodiments, the space in the body includes the alimentary canal. In still further embodiments, the space in the body comprises an interstitial space, as may occur in any tissue or organ in the body. The inventions further relates to a method of using the material deposition-countering bodily indwelling system, the method including moving the device. Moving the device may include any method summarized above, as applied to an indwelling urinary tract device and system.
In broad aspect, the invention relates to a device and a method to operate the device wherein an indwelling device moves in response to an input of energy, and by such movement the device counters the deposition of material as described above. In some embodiments, the movement is mediated by an operably connected movement-inducing actuator included with the device that transduces the energy input into the movement. Embodiments such as these are schematically represented by
In other embodiments, schematically represented by
With regard to a device, as just described in the context of an embodiment depicted by
Turning now to the various embodiments of the device that include a motion-inducing actuator, such actuator is operably connected with the structure of the device, and causes, on activation, movement of the device. The nature of the operable connection may vary, and does vary in accordance with the nature of the physical relationship between the actuator and the device. In some embodiments, the actuator and the device are structurally integrated, in some embodiments the actuator and the device, though operably connected are structurally separate or separable. Actuators require power or energy input to impart movement to the device; accordingly, energy may be conveyed to the actuator from an energy source by physical connection, by wireless connection, or by any other suitable mode or combination of modes. Typically. actuators that receive power by wireless means utilize an energy receiver such as an antenna to receive power from the source and convey it to the actuator. In some embodiments, where the device acts as its own actuator, the actuator-device may receive the energy itself also, without the intervention of a separate energy receiver.
Turning now with reference to the block diagrams of
In the various embodiments described below, indwelling devices will generally be designated as device 10, this designation can refer to any device, whether it has a movement-inducing actuator integrally incorporated therein, or whether it is has a motion-inducing actuator operably that is operably connected to the structure of the device, but structurally distinct therefore, of a device that lacks a motion-inducing actuator. In cases where the distinction is needed for an understanding of the invention, designation of device 10a will refer to devices with an integrated actuator, device 10b will refer to devices with a separate actuator, and device 10c will refer to devices that lack a distinct actuator and/or own energy receiver.
Various illustrative examples of embodiments of the invention will now be provided; it may be understood that variations on these embodiments may exist without departing from the basic elements described, including a device, a motion-inducing actuator, an energy receiver, and an energy source. As described, these elements may be clearly understood in terms of their function and functional relationships, while the physical form and relative degree of structural integration, connection, or quality of single structure combining various functions may vary. In
Embodiments of the invention include any device that dwells, or partly dwells in the urinary tract; the urinary tract extends from the kidney, through the ureters, the bladder, the urethra, and ends at the urethral opening.
The description now turns to a consideration of movement of embodiments of the inventive devise and system, and methods by which movement is induced. By methods of the invention, the movement of the device, as imparted by a movement-inducing actuator, or as in some embodiments, as directly induced by the reception of wirelessly transmitted energy by the device, such as sonic or ultrasonic energy, may be broadly characterized as movement either in relation to the position of the device with respect to the urinary tract in which the device resides, or the movement may be within the device, such as by deforming or vibrating the device. Translational movement of the device with respect to the urinary tract location may occur along any of the three spatial axes in which the device can freely move. Additionally, or alternatively, device movement can be complex, combining movements along any of the axes. Thus, to the extent that movement is allowed by the constraints of the placement of the device within the urinary tract, induced movement may, by way example, move the device longitudinally (proximally or distally) within the urinary tract, or rotationally within the urinary tract.
Additionally, induced movement of a device may include vibration or deformation of the device, and this vibratory movement within the device may further occur in concert with the previously described translational movement of the device within the urinary tract. Vibrational or deformational movement may occur within the device, it may occur along any spatial dimension defined by the axes of the device, it may be complex, and it may occur with multiples modes, and it may include resonance. Vibration may manifest as waves in three dimensional form, moving through the device, in any direction. Further, vibration may manifest in the form of two dimensional surface area distortion or reconfiguration, with transient expansion and contraction of localized areas. In such a case, if an area were to be marked by reference lines (see
Movement of a device may, in brief, be understood in the context of the physics of rigid body translations and deformations. Thus, the “moving” of a device may include any of moving translationally with resonance along any of linear or rotational degree of freedom, moving translationally without resonance along any of linear or rotational degree of freedom, or moving deformationally with modes of any order, along any of linear or rotational degrees of freedom, or any combination of translational and deformational movement.
Movements of the device, whether translational within the urinary tract or vibrational or deformational of the device itself, may further be characterized variously as being regular, irregular, periodic, or random. Motion may vary in terms of magnitude or amplitude, frequency, and periodicity. Occurrence of movement may be episodic, or it may be continuous over a period of time. Occurrence of movement may be set to run on a schedule, whether defined by minutes, hours, days, weeks, or months. To an extent, some of these variables are a function of the dimensions of the device and physical constraints imposed on the device. All these variables are further a function of—and controllable by the form and rate of energy being conveyed to the device by an energy source, as variously conveyed through an energy receiver, an actuator, or directly to the device itself. These movement variables and parameters are well known in the art. Further well known are the hardware and software of control systems, feedback loops, memory chips and programmable chips, all of which are included as embodiments of a larger system that comprises the inventive device. In some embodiments, such as those that utilize wireless transmission of energy to a device, control systems are typically external. In other embodiments, where energy sources are attached to—or implanted in the body, the energy sources and actuator may comprise integrated chips that control the function of the device. Further, the methods of the present invention draw from these known systems and methods of controlling parameters, and apply them to the inventive producing of motion in implanted medical devices, such as the indwelling urinary devices described herein.
The description now turns to further consideration of various embodiments of the material deposition-counter urinary tract device with regard to adaptations that support movement. In some embodiments, the urinary tract device includes a motion-inducing actuator, as shown in the embodiments represented by
In other embodiments, the device as a whole may be configured to optimize or focus received energy. In embodiments such as these, where the device or a portion thereof is configured in a form to focus incoming energy, such as ultrasound, such focus may facilitate efficient reception and transduction of energy into resonance. In other embodiments where a distinct actuator is included with the device, the device and the actuator may be configured so as to optimally couple with each other. Also, physical features of shape or composition that support movement in devices that lack actuators, may be included in actuator-containing devices toward the same advantage. Further, while ultrasound is used as an example of applied wireless energy, energy directed to the device through an actuator may also arrive by a physical connection. Resonance is an advantageous response to incoming energy as it transduces incoming energy into vibrational movement with high efficiency.
Embodiments that focus or enhance a movement or vibrational response to incoming wireless energy may include variations in materials or shapes of conventional devices beyond or in addition to differences associated with the inclusion of an actuator per se. A typical form of incoming energy appropriate for these embodiments is ultrasound, as transmitted from an external probe. As an example of an inventive variation of a conventional device, the composition of plastics that comprise a Foley catheter, or a portion of a Foley catheter, may be varied so as to have an elastic modulus different (typically higher, but in some embodiments, lower) than that of conventional devices, such that the catheter or portion thereof which will propagate vibration at a commensurately greater efficiency. In another example, the plastic of a Double-J stent may be formed with walls that vary in thickness periodically along the length of the stent, the varied periodic pattern being calibrated so as to support a resonant standing wave (see
The description now considers material deposition on surfaces and on devices that may not be tubular in form. Embodiments of the material deposition-countering device may counter the deposition of material on any surface of the device, including external surface and internal surfaces. Typical embodiments of the device are generally tubular in form, with a wall circumscribing a lumen, and circular or approximately circular in cross section. The cross sectional shape of such devices may vary, of course, according to the intended purpose of the device, and some portions of the device need not be tubular in form. Further, some urinary tract device embodiments may not be designed for the purpose of conveying fluid flow at all. Examples of such embodiments may include a wire or member of any kind, or a drug-eluting body; such devices comprise surfaces but may lack a lumen. The external surface of the tubular form of a device is adjacent to the wall of the portion of the urinary tract within which the device is residing, and the internal surface of the device circumscribes the lumen of the device through which urine flows. Materials deposited on the external surface of a device, by virtue of the close proximity of that surface to the inner surface of the urinary tract, are particularly vulnerable to disruption and dislodging by any kind of movement, translational, rotational, or vibratory, as provided by embodiments of the invention.
The description now further considers particulars of the materials that accumulate in devices in the urinary tract, which deposition is countered by embodiments of the inventive devise and method. In some embodiments, the device counters the deposition of material that includes a precipitate of one or more solutes included in the urine of the patient. Such precipitated solutes may include any one or more of calcium oxalate monohydrate, calcium oxalate dihydrate, calcium phosphate, magnesium ammonium phospate, struvite, hydroxyapatite, carbonate apatite, brushite, or uric acid. Precipitated solute in the form of stone or deposition typically commonly contains more than one of these species. Further, the composition of precipitated or deposited particulate matter varies according to the metabolic and dietary particulars of the individual, and accordingly, stones or deposition may contain other materials as well.
While material that precipitates in the urinary tract in the absence of a foreign nidus such as a device generally takes the form of a discrete stone, when being deposited on a device, it may take less discrete forms, for example taking the form of amorphous plaque. In other embodiments, the deposition-countered material may be of thrombotic origin. In other embodiments, the deposition-countered material may include cellular matter, such as whole cells, cell fragments, or cell-derived debris. In still other embodiments, the deposition-countered material may include a biologically-derived film, the film derived either from the patient or from an organism that has infected the patient. Finally, deposited material may include any of such materials, whether mineral or organic, in any proportion.
The deposition of material as described above may be countered or counteracted by embodiments of the device, as practice by embodiments of the method of using the device. Counteracting deposition may variously include impeding the deposition of material to any degree at all, it may include completely preventing deposition of material, and it may include any degree of impeding deposition between these two extremes. Countering deposition may further include removing or diminishing some portion of material that has already been deposited. This aspect of the method, where extant deposition is diminished, may be understood to occur in an embodiment where a device is fitted with a motion-inducing actuator after a device has been inserted or implanted into the urinary tract. Such an embodiment is depicted in
The description now turns to a consideration of motion-inducing actuators and energy sources included in the invention. Motion-inducing actuators 20, as applied to the structure of urinary tract devices 10 throughout this application may be any suitable device or element that can transduce an amount of energy received into movement of the device. Examples include any of a motor, a mechanical transducer, a piezoelectric element, a shape memory polymer, an electroactive polymer, a shape memory alloy (such as Nitinol, for example), a miniature actuator, an electromechanical actuator, or an electromagnetic actuator. Piezoelectric elements based on crystals that change shape in response to an applied voltage represent a typical embodiment, and offer the advantage of being easily shaped into an appropriate form, easily integrated into devices, for having no macroscopic moving parts, and for having a low physical profile. Accordingly, piezoelectric elements are suggested as actuators in numerous exemplary embodiments shown and described herein, although other types of actuators may serve equally as well. Various mechanical transducers are described and depicted herein as well, such as the embodiments shown in
Energy sources 30, as applied to the inventive device described herein may by of any suitable type, physically connected or wirelessly connected to a motion-inducing actuator 20, or in some cases in wireless communication directly with a device such as that shown in
The description now turns to a consideration of exemplary embodiments, as depicted in
Energy may be provided to the motion-inducing actuator from a source either within the body, or from outside the body. The embodiments depicted in
The system and method described herein in the context of devices dwelling in the urinary tract may be also applied to any other indwelling or implanted device that is subject to receiving material deposition, and accordingly, are included as embodiments of this invention. Any such device adapted to at least partially dwell in the body may include a structure operably coupled to an actuator such that the actuator can induce motion in or of the structure, or alternatively, the device may be adapted to move in response to receiving or absorbing energy directed to it, as has been described above, particularly with reference to energy-focusing features or elements that may be adapted or configured in otherwise conventional devices. Further, as mentioned previously, embodiments need not include a lumen as does the urinary tract embodiment. Still further, in broader aspect, absorbing of energy by embodiments of the invention may include generation of heat in concert with movement, or alternatively, instead of movement.
Thus various embodiments of the inventive device may be those placed in any suitable space within the body, as for example, any space that accommodates a conventional medical device. For example, embodiments of the device may dwell in a body lumen, such as an auditory canal, a blood vessel, the heart, a bile duct, a lymphatic vessel, a salivary gland such as a parotid gland, a sinus, or a lacrimal duct, or a pulmonary lumen. An example of an embodiment of the invention thus may include a cardiac stent, wherein movement of the stent may prevent clot formation, particularly in the early post-implant period. In other embodiments, the device may dwell in a hollow organ, for example a portion of the alimentary canal, including any portion of the upper gastrointestinal tract, the stomach, and the lower gastrointestinal tract, the latter portion including the small and large intestine. An exemplary embodiment of the inventive device and method in this context may include an espophageal stent, where energy absorbance may render a therapeutic scarring to treat reflux. Still other embodiments may dwell in a body cavity, such as the pleural cavity or the peritoneal cavity. An example of such a device is a peritoneal dialyis catheter, which is subject to clogging by accumulation of material on its external surface. Other embodiments, as for example leads or sensors, may dwell in the interstitial space of any tissue or organ. The useful lifespan and effective operation of devices such as these are known to be frequently compromised by accumulation of material or adherence of cells and cellular material, and accordingly may benefit by disruptive movement.
Devices situated in these various locations in the body, such as a lumen, cavity, or hollow organ, will be adapted in size and shape appropriate for their designated function. As mentioned in the embodiments described herein that dwell in the urinary tract, these devices need not include a lumen. In fact, the only physical qualification is that the device comprise a surface, and for the inventive aspect of the device to be useful, the only qualification is that the surface be subject to a problematic deposition of material. Further, the environment in which embodiments of the device dwell need not be one that is bathed in or flushed by flowing fluid. The peritoneal cavity, for example, may contain fluid, but the fluid has no directional mass flow. The auditory canal, for another example, contains waxy secretion, but it is not liquid, and doesn't flow as a fluid. In embodiments of the device that are situated in environments such as these, the benefit of translational or deformational movement may be to prevent or impede the build up of environmental material, or the benefit may be to render the material into a state, such as being less dense or more loosely attached, for example, that provides functional benefit for the device, or renders the material into a state more easily removed by other means.
While the inventive device and method, as illustrated by the describe embodiments have been described in some detail by way of illustration, such illustration is for purposes of clarity of understanding only. Various terms have been used in the description to convey an understanding of the invention; it will be understood that the meaning of these various terms extends to common linguistic or grammatical variations or forms thereof. It will also be understood that when terminology referring to devices or equipment has used trade names, brand names, or common names, that these names are provided as contemporary examples, and the invention is not limited by such literal scope. Terminology that is introduced at a later date that may be reasonably understood as a derivative of a contemporary term or designating of a subset of objects embraced by a contemporary term will be understood as having been described by the now contemporary terminology. Further, while some theoretical considerations have been advanced in furtherance of providing an understanding of an invention, the claims to the invention are not bound by such theory. Further, it should be understood that the invention is not limited to the embodiments that have been set forth for purposes of exemplification, but is to be defined only by a fair reading of claims that are appended to the patent application, including the full range of equivalency to which each element thereof is entitled.
This application further claims priority under 35 U.S.C. § 119 to U.S. Ser. No. 60/795,493 of Lin and McCallum, filed on Apr. 28, 2006, entitled “Method to prevent material deposition and encrustation on devices in the urinary tract”, the disclosure of which is incorporated herein by this reference.
| Number | Date | Country | |
|---|---|---|---|
| 60795493 | Apr 2006 | US |
