Ophthalmic fluid delivery system
An ophthalmic fluid delivery environment that includes a human eye in an open position and an atomizer having a nozzle aimed at the human eye in the open position, wherein a plume of ophthalmic fluid mist is directed by the nozzle so that the mist is received by the human eye in the open position and the received mist has a momentum that is insufficient to trigger to at least one of an ocular blink reflex and a lacrimation reflex of the human eye that receives the mist.
The present application is a divisional application of U.S. patent application Ser. No. 10/851,611, filed on May 20, 2004, which claims priority under 35 U.S.C. § 119(e) to both U.S. Provisional Application No. 60/485,305, filed on Jul. 3, 2003 and U.S. Provisional Application No. 60/471,883, filed on May 20, 2003, wherein each of the above mentioned U.S. Patent and U.S. Provisional Applications are incorporated herein by reference.
FIELD OF THE INVENTIONThe present invention relates to drug delivery devices for dispensing liquid as an aerosol or atomized mist and, more particularly, for dispensing medicaments to the eye.
BACKGROUND OF THE INVENTIONPresently, conventional eye drops are the standard means of delivering medicaments to the eye. This means of ophthalmic drug delivery, however, has numerous problems. For example, the average eye drop (approximately 50 micro liters) far exceeds the eye's capacity (7 micro liters in the pre-corneal tear film and a maximum of about 30 micro liters in the lower cul-de-sac) effectively destabilizing and stripping the natural tear film. This results in a brief period of massive over-dosage, which is quickly cleared by reflex lacrimation, blinking and nasolacrimal drainage, resulting in sub-therapeutic drug levels until the next medication application. This approach represents very inefficient pharmacokinetics. Far smaller volumes of medicament (approximately one tenth of a conventional drop) are desirable and are, in fact, retained by the eye and “bio-available” for a substantially longer time.
Attempts to prolong ocular contact time by various adaptations, such as the use of particulate suspensions, have led to other drawbacks including ocular irritation and excessively slow drug release. Ointments and gels, though providing prolonged contact time, create obvious visual disturbances.
Further, local irritations and toxicities often result from the regular use of eye drops. These situations vary widely depending on the pharmacologic agent, preservatives and other additives being used, but this is clearly a very non-physiologic and inefficient system of medication administration. Chronic use of eye drops for such conditions as glaucoma and prolonged infections and inflammations can, in fact, cause substantial morbidity. Additionally, serious and even fatal reactions to sympathomimetic and beta-adrenergic blocking agents have occurred as a result of systemic absorption of eye drops via nasolacrimal drainage.
Besides the above issues, there are a great many difficulties that patients experience with the mechanics of eye drop administration. Elderly patients, the largest group of eye drop users, often have hand-eye coordination problems, tremors or arthritis, affecting the hands and/or the cervical spine, making eye drop administration difficult if not impossible. Many users report that they have trouble keeping track of their regimens and often repeat doses or miss them entirely, suffering potential consequences in either event. Further, pediatric patients, often unable to comprehend the reasons and benefits behind the administration of eye medication, often fight such application, typically resulting in underdosing due to the patient's attempts to prevent the eye drops from being administered, or overdosing, as a result of the administrator's attempt to ensure that sufficient dosage is being applied.
Additionally, very few regular users of eye drops, in any age group, actually observe the ideal technique of administration, including tear sac compression, to minimize excretory loss and potential systemic absorption. It is sometimes difficult to tell if the drop was properly instilled. Direct application to the cornea can result in the drop “bouncing” from the eye with little or no benefit.
Regular eye drop users commonly report using several drops which “missed” the eye until they are sure they properly instilled the drop. Also, many eye drop bottles are fabricated in such a way that loss is unavoidable as soon as the dropper is tilted. Finally, a significant number of regular users put another drop or two in the eye “just to be sure”. All of the above represent needless waste of expensive medication (many glaucoma medications cost $70-$80 for a 5 ml bottle) and also increased the risk of side effects, while actually reducing the therapeutic benefit.
The ophthalmic literature is rife with references to the need for a better means of ophthalmic drug delivery. With an estimate of 25 million users of eye drops in the United States alone, the magnitude of the public health issue is considerable. Accordingly, a new means of ophthalmic drug delivery is needed.
The concept of “spraying” medicated solutions on to the eye is not a new one. A number of devices have been conceptualized and developed for this purpose. Various means of atomizing and propelling solutions including mechanical pumps, gas-propelled jets and pistons, etc. Which have inherent drawbacks relating to difficulties with calibrating the flow velocity, volume and particle size of the emitted spray. See, for example, U.S. Pat. Nos. 3,170,462; 5,630,793; and 6,062,212.
It is hypothesized that the generated mist will expand and “therapeutically alter” but not significantly disrupt the physiologic tear film allowing for a more natural process in the transmission of therapeutic agents to the surface and the interior of the eye. A much smaller volume of solution can be administered below the blink and lacrimation thresholds, allowing for a prolonged time of application. The aggregate administration of a drug in thousands of 5-micron particles should significantly exceed that of a single eye drop, leading to greater concentrations of the drug (bioavailability). Furthermore, the surface tension of a standard drop is a barrier to “mixing” and tear film incorporation. This problem is expected to be avoided with micronebulization.
An additional benefit to mist administration of eye medications is the avoidance of dropper bottle contamination which commonly occurs from contact with the eyelid. In the professional office setting, this problem has led to many documented epidemics of viral keratoconjunctivitis. During medication administration via a dropper bottle to a patient with viral keratoconjunctivitis, the bottle tip may inadvertently touch the eye or eyelid of the affected patient, transferring the virus to the bottle tip. Subsequent medication administrations to other patients using the same dropper bottle transmits the virus to those patients.
Some of the beneficial features of an ophthalmic medication spray dispenser include the following: great ease of use; can be used in any “attitude” (i.e. With patient sitting, erect, lying down, head tilted back, etc.); abbreviated treatment cycle as compared to eye drop usage; improved bioavailability/efficacy; improved safety (reduced local and systemic side effects); improved sterility; increased compliance due to ease of use and “alert” systems; possibility of singular efficacy in the treatment of certain vision threatening infections; conservation of material (reduced volume, diminished waste/loss); and system (fixation target to help ensure proper application).
It would be beneficial to provide a system for applying the desired small amounts (7 to 10 micro liters) of optical medication, along with at least some of the above-listed beneficial features, while eliminating the drawbacks associated with previous means of drug delivery.
BRIEF DESCRIPTION OF THE INVENTIONBriefly, the present invention provides a fluid atomizer comprising a body having a proximal end and a distal end. A removable reservoir is connected to the body, wherein the reservoir contains a fluid disposed therein. A discharge plate is disposed at the distal end, wherein the discharge plate includes a plurality of openings extending therethrough. The atomizer further comprises propulsion means for transmitting the fluid from the reservoir to the discharge plate and through the plurality of openings, wherein transmission of the fluid through the plurality of openings atomizes the fluid.
Also, the present invention provides a fluid atomizer comprising a body having a proximal end and a distal end. A removable reservoir is connected to the body, wherein the reservoir contains a fluid disposed therein. A discharge plate is disposed at the distal end, wherein the discharge plate includes a plurality of openings extending therethrough. The atomizer further comprises propulsion means for transmitting the fluid from the reservoir to the discharge plate and through the plurality of openings, wherein transmission of the fluid through the plurality of openings atomizes the fluid. The atomizer also includes a system controller electronically connected to the propulsion means, wherein the system controller controls operation of the propulsion means.
Further, the present invention provides a fluid atomizer comprising a body having a proximal end and a distal end. A removable reservoir is connected to the body, wherein the reservoir contains a fluid disposed therein. A discharge plate is disposed at the distal end, wherein the discharge plate includes a plurality of openings extending therethrough. The atomizer further comprises propulsion means for transmitting the fluid from the reservoir to the discharge plate and through the plurality of openings, wherein transmission of the fluid through the plurality of openings atomizes the fluid. The atomizer also includes a means for spacing the discharge plate a predetermined distance from a target.
Additionally, the present invention provides a fluid atomizer comprising a body having a proximal end and a distal end. A removable reservoir is connected to the body, wherein the reservoir contains a fluid disposed therein. A discharge plate is disposed at the distal end, wherein the discharge plate includes a plurality of openings extending therethrough. The atomizer further comprises propulsion means for transmitting the fluid from the reservoir to the discharge plate and through the plurality of openings, wherein transmission of the fluid through the plurality of openings atomizes the fluid. The atomizer also includes a system controller electronically connected to the propulsion means, wherein the system controller controls operation of the propulsion means. The atomizer also includes a means for adjusting operation of the propulsion means to adjust an amount of the fluid transmitted across the discharge plate, wherein the means for adjusting operation of the propulsion means are operatively connected to the system controller.
The accompanying drawings, which are incorporated herein and constitute part of this specification, illustrate the presently preferred embodiments of the invention, and, together with the general description given above and the detailed description given below, serve to explain features of the invention. In the drawings:
Certain terminology is used in the following description for convenience only and is not limiting. As used herein, the term “distal” is meant to mean the discharge end of the inventive device and the term “proximal” is meant to mean the end of the inventive device held by user. The terminology includes the words above specifically mentioned, derivatives thereof and words of similar import. The embodiments illustrated below are not intended to be exhaustive or to limit the invention to the precise form disclosed. These embodiments are chosen and described to best explain the principle of the invention and its application and practical use and to enable others skilled in the art to best utilize the invention.
The present invention provides a novel device and method for ophthalmic drug delivery. In preferred embodiments, the present invention provides a small, hand-held, battery or ac powered device that nebulizes liquid eye medications into a fine mist. The mist from the device is directed at the eye to be treated and the drug is delivered via the mist.
A preferred means of forming the mist is by ultrasound energy generated by a piezoelectric transducer or other suitable piezo device. A small plume of nebulized solution is generated, consisting of particles measuring what is believed to be an average of about five microns in diameter. The volume of each emission is dependent on the rate of mist generation (typically measured in micro liters per second) as well as the duration of the operation of the device, which may be easily varied by using an electronic control circuit. The shape, dimensions and focus of the emitted mist are proportioned for delivery to the human eye. The momentum of the mist is subliminal to the ocular blink and lacrimation reflexes and may also create a soothing sensation in the eye. The device is equally efficient when used in any “attitude” from a natural, upright head posture to leaning forward or lying back. Application time is significantly abbreviated compared to eye drop usage, which typically requires several maneuvers and careful attention to detail to ensure proper administration.
One preferred embodiment of the invention is now described with reference to
Referring to
The head portion 110 includes the body 130 that connects the reservoir 120, the prime mover 140, and the nozzle assembly 150 together. The head portion 110 is connected to the handle portion 160 and provides a conduit for electrical leads (not shown) extending from the reservoir 120 and the prime mover 140 to the system controller 190.
ReservoirReferring to
The reservoir 120 is preferably shaped to maintain contact with the prime mover 140 when the device 100 is held in a preferred operational orientation while spraying into an eye (as shown in
Referring back to
Preferably, the reservoir 120 includes an engagement surface 128 disposed proximate to an upper and a lower side of the reservoir 120. The engagement surface 128 slides over a corresponding extension in the body 130, as shown in
In the embodiment shown in
For a reservoir 120 having a rigid form, such as the reservoir 120 shown in
Alternatively, as shown in
An air vent 1223 in the housing 1222 allows the collapsible bladder 1220 to collapse as the fluid 122 is withdrawn from the reservoir 1218, so that no adverse suction forces are generated during operation of the device 100. The air entering the vent 1223 does not need to be filtered, since the bladder 1220 isolates the fluid 122 from the air. In this embodiment, no make-up air is required to enter the bladder 1220.
Without limiting the type of fluids that could be contained in the reservoir 120, 1218 and dispensed by the present invention, diagnostic agents used by the medical professional that could be delivered with the present invention include mydriatics/cycloplegics, anesthetics, flourescein and flourescein/anesthetic combinations, and mydriatic reversal agents. Other agents which could be delivered with the present invention include over-the-counter agents, e.g., ophthalmic decongestants and lubricants, glaucoma medications (prestaglandins, beta blockers, alpha adrenergic agents, carbonic anhydrase inhibitors, miotics), and other ophthalmic medications. Optionally, several different therapeutic agents can be custom formulated in a single fluid to simplify adherence to multiple medication regimens.
Again, while an envisioned used for the device 100 of the present invention is directed toward ophthalmic use, those skilled in the art will recognize that the device 100 of the present invention may be used in other areas, such as respiratory treatment, and that other fluids, including respiratory medicaments, may be contained in the reservoir 120 instead.
Preferably, for photo-sensitive medicaments, the reservoir 120 may be tinted to prevent the transmission of certain deleterious wavelengths of light to the fluid 122 to prolong the useful life of the medicament in the reservoir 120. The tint may be a dark brownish tint that is presently used for such medicaments in bottle/eye dropper form.
Optionally, as shown in
The self-sealing valve 1224 is preferably biased toward a closed position, such as by a helical spring (not shown). A seal, such as an o-ring 1228, seals the valve 1224 against the wall 1226 of the reservoir 120 to eliminate fluid leakage from the reservoir 120 when the valve 1224 is in the closed position. A valve stem 1230 extends distally from the valve 1224. When the reservoir 120 is inserted into the body 130, the proximal end 142 of the prime mover 140 engages the valve stem 1230 and forces the valve stem 1230 into the reservoir 120, opening the reservoir 120 into fluid communication with the prime mover 140.
An alternative embodiment of a reservoir 1236 is shown in
As the device 100 is operated and medication is consumed, the fluid 122 is drawn along the tube 1238. The diameter of the tube 1238 is preferably specified in relation to the viscosity of the fluid 122 to insure that surface tension causes the fluid 122 to move in a column along the tube 1238, i.e., no air is drawn in by the prime mover 140 until the fluid 122 is consumed. This design has the advantage of using nearly 100% of the medication loaded into the tube 1238. This configuration has the further advantage of allowing the device 100 to operate in any orientation, even in zero gravity environments. Referring to
While a design of a reservoir 120 with a collapsible bladder 1220 and a design of a reservoir 1236 with a coiled tube 1238 are shown, those skilled in the art will recognize that other designs of reservoirs may be used.
Optionally, as shown in
Also optionally, a low level sensor 1250, shown in
Referring back to
The body 130 preferably includes a connection device, such as an orifice 132, for attaching to the handle portion 160. However, those skilled in the art will recognize that other connection methods, such as snap fit, bayonet clips, or other suitable mechanisms known to those skilled in the art may be used. Preferably, the body 130 connects to the top 162 of the handle portion 160 in only a single orientation so that electrical contacts in each of the body 130 and the handle portion 160 properly engage each other when the head portion 110 is connected to the handle portion 160.
The body 130 also includes, at the proximal end of the body 130, a collar spacer 133 that is fixedly connected to the body 130 to provide optimum spacing of the proximal end 142 of the prime mover 140 within the reservoir 120 to optimize the ability of the prime mover 140 to withdraw the fluid 122 from the reservoir 120 during operation of the device 100.
The body 130 houses the prime mover 140, and provides connection means for the reservoir 120, the nozzle assembly 150, and the handle portion 160. The retainer 135 is fixedly connected to the body 130 and also releasably retains the reservoir 120 so that the reservoir 120 is removable from the remainder of the device 100. As described above, the retainer 135 may include an engagement surface, or alternatively, other connection means, such as threaded connections, or other means known to those skilled in the art.
The body 130 includes a generally tubular passage 136 that is sized to accept the proximal end 142 of the prime mover 140. A spacer recess 137 is disposed at the distal end of the body 130, preferably below the passage 136. The spacer recess 137 is used to releasably retain a targeting means, which will be described in detail later herein.
A seal 138 is disposed about the proximal end of the passage 136. The seal 138 prevents any fluid 122 from leaking out of the reservoir 120 when the reservoir 120 is attached to the body 130. In the present embodiment, the seal 138 is formed in the shape of a ring by injection molding or liquid injection molding using medical grade silicones or urethanes with durometers in the range of 5 to 30 shore a.
Preferably, the body 130 includes an activation indicator 1310 that is disposed on the top of the body 130. The activation indicator 1310 may be a light, such as an led, that provides constant illumination as long as the activation switch 180 is depressed; a light that provides blinking illumination; a sound that provides audible indication, either by constant or by periodic beeping; some combination of these listed indicators, or some other indication that would indicate to the user that the device is ready for operation. The activation indicator 1310 operates when the activation switch 180 is initially depressed by the user. The activation indicator 1310 alerts the user that the device 100 is “on” and is about to spray the fluid 122 from the nozzle assembly 150. The activation indicator 1310 is electronically connected to the system controller 190 via electrical leads (not shown).
The body 130 may be machined from solid metal or plastic stock, or may be injection molded with polymer resins such as abs, styrene, pvc, or other suitable material, as will be recognized by those skilled in the art. The body 130 may be injection molded or manufactured by other methods known by those skilled in the art. Preferably, the body 130 has a durometer within the range of approximately 90 to 100 shore a.
Prime MoverReferring still to
The prime mover 140 includes a proximal end 142, a distal end 144, and a central portion 146 disposed between the proximal end 142 and the distal end 144. A longitudinal axis 148 extends along a length of the prime mover 140 between the proximal end 142 and the distal end 144. A longitudinally extending lumen 1410 extends along the longitudinal axis 148 and extends the length of the prime mover 140. Preferably, a perpendicular cross section of the lumen 1410 is generally circular in shape and has a diameter of approximately between 0.25 and 1.0 mm. However, those skilled in the art will recognize that the lumen 1410 may have other cross sectional shapes, such as a generally oblong, oval, or elongated shape.
The central portion 146 includes at least two generally annular piezoelectric elements 1412, 1414 that surround the lumen 1410. The piezoelectric elements 1412, 1414 are electrically connected to the power source 170, which drives the piezoelectric elements 1412, 1414 during operation of the device 100.
Referring to
Referring back to
The nozzle assembly 150 is shown in an exploded perspective view in
The cap 152 is generally annular, with a central opening 1510 disposed along the longitudinal axis 148. Preferably, the body of the cap 152 extends in a distal direction and generally away from the longitudinal axis 148 to form a concave volume 1512 distal of the central opening 1510. The concave volume 1512 reduces the likelihood that a foreign object, such as a user's finger, will touch the mesh plate 156, potentially contaminating the plate 156.
The cap 152 preferably includes a releasable lock feature, such as a female threaded connection (not shown) that releasably threadingly engages the retainer 158, which has a mating twist lock feature, such as a mating male threaded connection (not shown). However, those skilled in the art will recognize that the cap 152 may engage with the retainer 158 by other means not shown, such as by snap engagement, bayonet means, or other suitable means known to those skilled in the art.
The mesh plate 156 is biased against the distal end 144 of the prime mover 140 by the biasing element 154, such as a helical spring, that is disposed between the cap 152 and the mesh plate 156. The biasing element 154 ensures that the mesh plate 156 is firmly engaged with the distal end 144 of the prime mover 140 to provide proper dispersion of the fluid 122 through the mesh plate 156 during operation of the device 100. While a helical spring is preferred as the biasing element 154 because a helical spring provides a generally uniform biasing force around its perimeter, those skilled in the art will recognize that other types of biasing elements, such a leaf springs, may be used instead. As shown in
The mesh plate 156 is formed of a rigid material that is biocompatible and non-oxidizing, such as alumina ceramics, titanium allows, or stainless steel alloys. As shown in
Enlarged cross sections of several embodiments of openings 1520a, 1520b, 1520c, 1520d, and 1520e in mesh plates 156a, 156b, 156c, 156d, 156e are shown in
The mesh plate may 156 incorporate one of several designs of openings 1520 as shown in
In an alternate embodiment, shown in
It is preferred that the openings 1520 in the mesh plate 156 generates mist particle sizes in the average range of between approximately 0.5 and 10 microns in diameter. It is also desired that the mist generated through the nozzle assembly 150 preferably extends about 7.5 to 10 cm in a mist plume diverging with a solid angle of approximately 10-20 degrees and traveling at a velocity of between approximately 4 and 30 cm per second, discharging approximately between 2 and 20 microliters per second, and preferably, between 7 and 10 microliters of fluid per second.
Referring back to
The mesh plate 156 is removable from the remainder of the device 100 for cleaning, such as in an alcohol or other cleaning solution. To clean the mesh plate 156, the retainer 158 is removed from the body 130, releasing the cap 152, the biasing element 154, the mesh plate 156, and the retainer 158 from the remainder of the device 100. The biasing element 154 biases the mesh plate 154 against the retainer 158, keeping the nozzle assembly 150 intact. After cleaning, the nozzle assembly 150 is reconnected to the remainder of the device 150. The distal end 144 of the prime mover 140 engages the mesh plate 156, forcing the mesh plate 156 away from the retainer 158 so that the mesh plate 156 may be able to vibrate when excited by the prime mover 140.
Optionally, as shown in
Different medications and/or ophthalmic treatment regimens may require different amounts of a medication to be administered with each use of the device 100. Alternatively, a larger patient may need a larger dose of a medication than a smaller patient. Therefore, an ability to adjust dosage amount may be required. The device 100 may optionally be equipped with user-accessible adjustments for flow rate (mist volume) and total flow (dose). These adjustments may be electromechanical (knobs or wheels operating potentiometers), or electronic (buttons or keys providing digital data to the system controller 190).
In one embodiment of a dosage adjustment, a dosage adjuster 1530, 1530a may be disposed on the nozzle assembly 150, such as is shown in
While the dosage adjuster 1530 may be disposed on the nozzle assembly 150 as shown, those skilled in the art will recognize that a dosage adjuster 1530a may be disposed on the handle portion 160, as is alternately shown in
In order to ensure that dosing is consistent, the location of the nozzle assembly 150 relative to the eye during dispensing of medication may also need to be controlled. Various targeting mechanisms have been developed for this purpose. Referring back to
Preferably, the light sources 1546, 1548 and the lenses 1542, 1544 form a pattern on the target eye when the device 100 is aimed at the eye and the activation switch 180 is depressed. The pattern may be formed by separate masks 1550, 1552 that are disposed between each light source 1546, 1548 and its respective lens 1542, 1544, as shown in
In addition to assisting in determining the optimum distance for spacing the device 100 from the eye, the targeting mechanism 1540 also aids in accurately aiming the device 100 at the eye, so that the mist generated by the device 100 is directed toward the middle of the eye, and not off to the side.
While the targeting mechanism 1540 described above is useful for a professional practitioner to use to aim the device 100 at a patient, those skilled in the art will recognize that an alternative embodiment of a targeting mechanism (not shown) may be used to by a patient on himself/herself by directing the targeting mechanism onto his/her retina.
Handle PortionReferring back to
In a non-use operation, the device 100 is preferably disposed in the base 166, as shown in
Preferably, the handle portion 160 and the base 166 may be separately machined from solid metal or plastic stock, or may be injection molded with impact resistant polymer resins, such as abs, polycarbonate, pvc, or other suitable material, as will be recognized by those skilled in the art. The handle portion 160 may optionally include a rubberized grip 168, at least along a length of the handle portion 160 facing the distal end of the device 100. The rubberized grip 168 is softer for the user and helps prevent the user from accidentally dropping the device 100. The grip 168 may also include indentations for a user's fingers to enhance ergonomics. The grip 168 may be manufactured from a material having a hardness in the range of 10-50 shore a that may be molded separately and bonded onto the handle portion 160.
Referring now to
The targeting means 1620 includes a generally elongated member 1622 that includes a connected end 1624 that is releasably inserted into the spacer recess 137, and a free end 1628 that is disposed away from the connected end 1624. As shown in
Preferably, the elongated member 1622 is constructed from impact resistant polymer resins, such as abs, polycarbonate, pvc, or some other suitable rigid material to minimize deflection of the elongated member 1622 during operation. Also preferably, the free end 1628 is either coated with or constructed from a soft material, such as rubber in order to reduce the likelihood of eye injury in the event that the free end 1628 accidentally engages the eye.
PowerA preferred power source 170 for the device 100 is battery power. As can be seen in
The battery 172 may be a single-use lithium ion or alkaline type, or the battery 172 may be rechargeable lithium-ion, nickel-cadmium, nickel-metal-hydride, or other battery type. The battery 172 may be a single battery or a plurality of batteries electrically connected in series. For example, two lithium photo batteries neda/ansi type cr2 (e.g. Duracell ultra cr2 li/mno2) may be connected in series will be used to power the device 100. The batteries 172 are preferably rated for 3v and approximately 2000 mah. The batteries 172 are connected in series to provide a total capacity 2000 mah at 6v. The batteries 172 preferably have a peak current rating of at least 1.8 a.
If a rechargeable battery is used, a charger is required. Those skilled in the art will recognize that the charger may be integrated into the device 100 or enclosed in a separate enclosure, such as in the base 166. The base 166 includes a standard 110v electrical cable 1610 extending therefrom that is electrically connected to an ac/dc converter (not shown) in the base 166 that converts 110v ac supply to 6v dc. The base 166 also includes a pair of contacts (not shown) that engage recharger contacts (not shown) in the bottom end 165 of the handle portion 160 when the device 100 is inserted into the base 166.
Alternatively, the device 100 may be designed such that the battery 172 can be easily removed from the device 100 and charged in a separate charger (not shown). A further alternative is to replace the battery with an ac-to-dc converter, and power the device 100 through a line cord connected to an ac source.
Activation SwitchAn activation switch 180 extends through the handle portion 160 to activate the device 100 upon a user engaging the activation switch 180. The activation switch 180 is preferably a button, as is shown in
The activation switch 180 is electronically connected to the system controller 190 via leads 182, 184. Preferably, the activation switch 180 is a three-position switch such that, when the activation switch 180 is depressed an initial amount from an open position to an initially closed position, the device 100 is activated. This activation illuminates the activation indicator 1310 to indicate that the device 100 is about to operate. When the activation switch 180 is completely depressed, the activation switch 180 transmits a signal, through the system controller 190, to operate the prime mover 140 for a period of time determined, through the system controller 190, by the settings on the dosage adjuster 1530. Preferably, the time period for operation extends between approximately 0.5 and 5 seconds. However, operation time of the prime mover 140 is not dependent on the duration of time that the activation switch 180 is depressed, but on the settings of the dosage adjuster 1530. However, it is preferred that, if the activation switch 180 is depressed for an extended period of time, such as greater than two seconds, the system controller 190 interprets the signal received from the activation switch 180 as a signal to run the device 100 continuously for a predetermined, extended period of time, such as thirty (30) seconds, such as to run a cleaning solution such as saline, through the device 100 to clean the device 100. Alternatively, if the activation switch 180 is depressed for longer than the predetermined period of time, the system controller 190 will provide power for the prime mover 140 to operate as long as the activation switch 180 is fully depressed.
ElectronicsThe primary function of the system controller 190 is to energize the prime mover 140, which is preferably a piezoelectric transducer assembly or other piezo device, as described above. When energized, the prime mover 140 generates a mist of fluid droplets from the fluid 122. The energizing signal for the prime mover 140 must excite the prime mover 140 at the proper resonant frequency, and must supply enough energy to the prime mover 140 to cause misting. A simple user interface, such as the activation switch 180, is required for operation and control of the prime mover 140. A microprocessor 192 will be used to provide intelligence for the interface between the activation switch 180 and the prime mover 140, and to supervise the circuits driving the prime mover 140, as well as all of the electronic features.
The system controller 190 controls operation of the device 100 and includes a microprocessor 192, preferably in the form of a pcba (printed circuit board assembly), to incorporate of the electronics for operation of the device 100.
The activation switch 180 is part of a normally open (“no”) circuit that includes the activation indicator 1310. As described above, the activation switch 180 is a three-position switch, with the first position in the no condition. The second position, when the activation switch 180 is depressed part way, powers the activation indicator 1310 to indicate to the user that the device 100 is on. The third position, when the activation switch 180 is fully depressed, activates the device 100 to operate the prime mover 140 to generate a mist from the nozzle assembly 150 for medication dispensing to the patient. To conserve power and lengthen operational battery life, all circuits are disconnected from power while the activation switch 180 is open.
A power management & low battery indicator 194 includes an electronic circuit that automatically measures the battery voltage and provides a visual or audible (beeping) indication if the voltage has dropped below a preset level. Power management chips (also known as “gas gages”) are commercially available for various battery types, or such a circuit may be constructed from discrete components. Preferably, the circuit also provides “sleep” or “hibernate” modes, as are known to those skilled in the art, in which battery life is extended by reducing power consumption when the device 100 has been inactive for a preset amount of time.
An optional power conditioning circuit 196 provides a constant and regulated voltage to the rest of the system controller 190. Power conditioning chips are commercially available for various voltage and current requirements, or alternatively, such a circuit may be constructed from discrete components.
A voltage step-up & driver (vsd) circuit 198 powers the prime mover 140. For a prime mover 140 that includes the piezo device described above, the purpose of the vsd circuit 198 is to drive the piezoelectric crystal contained in the piezo device at a desired resonant frequency. Different crystals and piezoelectric assemblies have different resonant frequencies, as well as different q-factors, so the vsd circuit 198 is preferably custom designed to match the operating characteristics of the particular piezo device. The vsd circuit 198 contains an oscillator formed of integrated and/or discrete components such as power transistors, power diodes, capacitors, and coils.
Preferably, the piezo device is driven by a square wave at its resonant frequency in the range of 50 khz to 70 khz. Since each piezo device has a slightly different resonant frequency, the circuit will use a phase lock loop (pll) or other feedback technique with a voltage controlled oscillator (vco) to lock on to the piezo resonant frequency and to automatically adjust the drive signal frequency as the resonant frequency varies. The piezo device is preferably driven by a peak-to-peak signal in the range of 200v, or as appropriate to provide sufficient misting. Using the preferred omron piezoelectric device described above, the mist volume produced with this method is in the range of approximately 10 to 100 microliters/second.
The system controller 190 also optionally includes a heater control 1910 and that is electronically connected to the optional reservoir heater 1248 to heat the fluid 122 in the reservoir 120, as desired. The heater control 1910 includes a feedback loop to control the desired temperature of the fluid 122 in the reservoir 120. A heater power supply 1912 is also electronically connected to the system controller 190 to provide a power supply to the optional heater 1248.
Low Fluid LevelIf the device 100 includes the low level sensor 1250 in the reservoir 120 as described above, the device 100 also includes a low fluid level alarm 1914 that is set to alarm when the fluid 122 in the reservoir 120 is depleted to a predetermined level. The low reservoir sensor 1250 is programmed to transmit a signal to the system controller 190 when the fluid level reaches the predetermined level. The system controller 190 in turn transmits a signal to the alarm 1914. The alarm 1914 may be a visual alarm, such as a blinking light, or the alarm 1914 may be an audible alarm, such as a beep.
Dosage AdjustmentA manual method and apparatus for adjusting dosage amount dispensed during operation of the device 100, using the dosage adjuster 1530, 1530a has been previously described. Adjustment of the dosage adjuster 1530, 1530a transmits a signal to a dose control circuit 1916 to determine the length of time that the prime mover 140 operates to dispense the fluid 122 from the reservoir 120 to the patient. The system controller 190 also includes a flow volume control circuit 1918 that determines the volume of the fluid 122 per unit time that is dispensed through the prime mover 140. The total amount of the fluid 122 dispensed is determined by the value of the flow rate as determined by the flow volume control circuit 1918 times the length of time of operation of the prime mover 140 as determined by the dose control circuit 1916. Preferably, the flow volume control circuit 1918 is preprogrammed into the system controller 190, while the dose control circuit 1916 may be manually adjusted based on the type of medication and the dosage that the prescribing physician determines is necessary based on the patient's condition.
Alternatively, instead of manually adjusting the dosage amount, the dosage amount may be adjusted electronically, such as by external calibration of the system controller 190 to adjust operational values of the dose control circuit 1916 and the flow volume control circuit 1918 based on need.
Dosage Complete IndicatorThe system controller 190 also includes a “dosage complete” indicator 1920 that indicates when the device 100 has dispensed the prescribed amount of fluid 122 from the reservoir 120. The indicator 1920 may be may be a visual alarm, such as a blinking light, or the indicator 1920 may be an audible alarm, such as a beep. The indicator 1920 preferably is activated after a slight time delay, such as approximately 0.5 second, after the device 100 ceases to dispense the fluid 122 from the nozzle assembly 150. This delay ensures that the user does not remove the device 100 from in front of the patient's eye until all of the prescribed dose of medication has been dispensed from the device 100. Since the system controller 190 controls operation of the prime move 140, the system controller 190 is able to calculate the desired delay time between stopping operation of the prime mover 140 and sending the signal to the indicator 1920 to indicate that the dosage is complete.
Targeting OpticsIf the optional electronic targeting mechanism 1540 is used, depressing the activation switch 180 to the first position transmits a signal to the system controller 190 to activate the targeting mechanism 1540, illuminating the light sources 1546, 1548 to project images on the patient's eye. The targeting mechanism 1540 remains activated when the activation switch 180 is depressed to the second position. When the activation switch 180 is released, signal to the system controller 190 ceases, and the targeting mechanism 1540 is deactivated by the system controller 190.
Outside CommunicationsOptionally, the device 100 may include an input/output (i/o) device 1922 for transmitting information between the device 100 and an outside device, such as a personal computer, pda, or other such electronic device that is capable of displaying information transmitted from the device 100. Information that may be transmitted from the device 100 includes, but is not limited to, usage information, such as the number of times the device 100 was used, and at what times; dosage amount per application; and current and voltage draw of the device 100 during use, as well as other operational information about the device 100. Further, information may be transmitted from the outside device to the device 100. Such information may include, but is not limited to, clearance information to clear the system controller 190 memory of previous information that has already been downloaded to the outside device; operational information that allows the device 100 to be used with particular medicament reservoirs; temperature settings for the heater control 1910; and operational duration information to adjust the dose control circuit 1916 and the flow volume control circuit 1918 to adjust dosage amounts, as well as other information that may be transmitted to the system controller 190.
As shown in
A pediatric version of a device 200 according to an alternate embodiment of the present invention, shown in
Alternatively, a veterinary version of a device 300 according to yet another alternate embodiment of the present invention, shown in
The embodiments shown and described above may be offered in a reusable configuration. In this event, the parts may be injection molding from clear polymer resins that withstand repeated sterilization by steam autoclave, such as autoclaveable versions of acrylics, styrenes, and polycarbonates.
Alternatively, the embodiments shown may be offered as a sterile disposable. In this case it may be injection molded from a wide variety of clear polymer resins, including acrylics, styrenes, urethanes, pmma, and polycarbonates. These resins are generally compatible with industrial sterilization by e-beam, gamma, and eto.
UseBetween uses, the device 110 is typically stored in the base 166, with the bottom end 165 of the handle portion 160 inserted into the cavity 167 in the base 166. The electrical cable 1610 is connected to an external power supply to provide electrical power to the batteries 172 to charge/recharge the batteries 172. The heater 1248, if used, heats the fluid 122 in the reservoir. The temperature of the fluid 122 is controlled by the heater controller 1910 to maintain the fluid 122 at a desired temperature.
The device 100 is designed so that it can be used by one person to self administer medicament, such as a patient in his/her home, or, the device 100 can be used by one person to administer medicament to a second person, such as a medical professional treating a patient in a medical office or a hospital setting.
For self use, the user removes the device 100 from the base 160 and aims the discharge end of the nozzle assembly 150 toward the eye into which the user intends to insert the eye medication. If the optional mechanical targeting means 1620 is connected to the device 100, the user inserts the connected end 1624 into the spacer recess 137. The user then uses the free end 1628 of the targeting means 1620 to depress the eyelid. When the device 100 is in the desired position, the user then uses his/her thumb, as shown in
For professional use on a patient, the user, such as an optometrist or an ophthalmologist, removes the device 100 from the base 160 and aims the discharge end of the nozzle assembly 150 toward the eye into which the user intends to insert the eye medication. If the optional mechanical targeting means 1620 is connected to the device 100, the user inserts the connected end 1624 into the spacer recess 137. The user then uses the free end 1628 of the targeting means 1620 to depress the eyelid. When the device 100 is in the desired position, the user then uses his/her index finger, as shown in
If the optical targeting mechanism 1540 is used, the user aims the device 100 generally toward the patient's eye and, using his/her forefinger, as shown in
The remainder of the description of the operation of the device 100 is the same whether the device 100 is being used for self-administration of medication or whether the device 100 is being used by a professional to administer medication to a patient.
The user presses the activation switch 180 to the second position and then releases the activation switch 180, transmitting a signal to the system controller 190 to operate the prime mover 140. An electronic operational signal is transmitted through the power management circuit 194 and the vsd circuit 198 to the prime mover 140 which, in the case of the piezoelectric device described above, causes the piezoelectric device to vibrate, preferably at an ultrasonic frequency, along its longitudinal axis 148. The prime mover 140 is operated for a predetermined amount of time, preferably between approximately 0.5 and 2 seconds, as programmed into the system controller 190 prior to use. The prime mover 140 operates for the predetermined amount of time, regardless of how long the activation switch 180 is depressed, unless the activation switch 180 is depressed in excess of a predetermined period of time, such as 5 seconds, as will be described in more detail later herein.
The vibration of the prime mover 140 draws fluid 122 from the reservoir 120 and through the lumen 1410. The fluid 122 exits the distal end 144 of the prime mover 140 and passes through the openings 1520 in the mesh plate 156, where the fluid 122 is broken into micron-sized particles, which are directed toward the patient's eye. After the prime mover 140 has operated for the predetermined period of time, the system controller 190 ceases to transmit the operational signal and the prime mover 140 stops. At this time, the system controller 190 transmits a signal to the dose complete indicator 1920 to indicate to the user that the dosage is complete.
If the user is using the mechanical targeting means 1620, the user preferably removes the connected end 1624 from the spacer recess 137 and discards the elongated member 1622 to ensure that any bacteria from the patient's eye is not transmitted to the targeting means 1620 and then retransmitted to the next patient.
If the level of the fluid 122 in the reservoir 120 drops below a predetermined level, the low reservoir sensor 1250 transmits a signal to the system controller 190, which in turn transmits a signal to the low reservoir indicator 1914, informing the user that the reservoir 120 must be removed and a new reservoir must be inserted into the body 130.
If the low battery indicator 194 indicates that the power source 170 is at lower power, the user may insert the device 100 into the base 166 to charge the power source 170, or alternatively, replace the power source 170.
In the event that the user desires to change medication in the reservoir 120, it is recommended that the device 100 be “flushed” after removing the original medication but before using the new medication, so as not to contaminate the new medication with the old medication. In such an instance, the user inserts a reservoir containing a cleaning fluid, such as a saline solution into the body 130, and depresses the activation switch 180 in excess of a predetermined period of time, such as 5 seconds. The system controller 190 recognizes the extended depression of the activation switch 180 as the start of a cleaning cycle and operates the prime mover 140 for an extended period of time, such as for 30 seconds, or some other predetermined time, as desired. At the end of the cleaning cycle, the dose complete indicator 1920 may activate, alerting the user that the device 100 is clean, and that a new medication may now be used in the device 100.
While the embodiments of the present invention described above are preferably used to deliver medicament to a patient's eye, those skilled in the art will recognize that the embodiments of the present invention may be used with a respiratory medication instead of an ophthalmic medication, and that the invention may be used in the treatment of respiratory ailments instead of ophthalmic ailments.
It will be appreciated by those skilled in the art that changes could be made to the embodiments described above without departing from the broad inventive concept thereof. It is understood, therefore, that this invention is not limited to the particular embodiments disclosed, but it is intended to cover modifications within the spirit and scope of the present invention as defined by the appended claims.
Claims
1. An ophthalmic fluid delivery environment, comprising:
- a human eye in an open position;
- an atomizer having a nozzle aimed at the human eye in the open position, wherein a plume of ophthalmic fluid mist is directed by the nozzle so that the mist is received by the human eye in the open position and the received mist has a momentum that is insufficient to trigger to at least one of an ocular blink reflex and a lacrimation reflex of the human eye that receives the mist.
2. The environment of claim 1, wherein the human eye in an open position is held open without the aid of mechanical aids.
3. The environment of claim 1, wherein the mist contains an amount of ophthalmic medicine and the momentum of the mist is such that substantially all of the amount of ophthalmic medicine received by the human eye is retained by the human eye.
4. The environment according to claim 1, wherein the ophthalmic fluid is selected from the group consisting of mydriatics/cycloplegics, anesthetics, flourescein, flourescein/anesthetic combinations, mydriatic reversal agents, ophthalmic decongestants, ophthalmic lubricants, and glaucoma medications.
5. The environment according to claim 1, wherein the glaucoma medications are selected from the group consisting of prestaglandins, beta blockers, alpha adrenergic agents, carbonic anhydrase inhibitors, and miotics.
6. The environment according to claim 1, wherein the atomizer discharges the ophthalmic fluid having a velocity of between approximately 4 and 30 centimeters per second.
7. The environment according to claim 1, wherein the atomizer discharges the ophthalmic fluid between approximately 2 and 10 microliters per second.
8. The environment according to claim 1, wherein the plume of ophthalmic fluid contains an amount of ophthalmic medicine and the momentum of the plume is such that substantially all of the amount of ophthalmic medicine is received and retained by the eye.
Type: Application
Filed: Oct 6, 2008
Publication Date: May 7, 2009
Inventor: James F. Collins, JR. (Long Island City, NY)
Application Number: 12/287,150
International Classification: A61M 11/00 (20060101);