Patent Application
20230372151
One aspect of this disclosure relates to techniques for draining a fluid that is referred to as aqueous humor from an eye of a human, in order to reduce intraocular pressure. Other aspects are also described.
Intraocular pressure (TOP) refers to the pressure of a fluid known as the aqueous humor, AH, inside the eye. The pressure is normally regulated by changes in the production and outflow of the AH, but some persons suffer from disorders, such as glaucoma, which cause chronic heightened TOP. Over time, heightened TOP can cause damage to the eye's optical nerve, leading to loss of vision. Presently, treatment of glaucoma involves periodically administering pharmaceutical agents to the eye to decrease TOP. These drugs can be delivered by injection or eye drops.
For those persons who are not responsive to pharmaceutical treatments, there is another form of therapy in which a glaucoma drainage device is implanted into their eye. In such a device, a passive drainage tube is implanted that connects the anterior chamber of the eye to a plate that is, for example, attached between the sclera and the conjunctiva. The plate is an outflow site into which the AH can drain, thereby reducing the TOP. These, however, have had mixed success rates. As early as one year after the device has been implanted, the person's immune response can produce sufficient scarring, in a tissue bleb that is formed at the outflow site, that stops the intended drainage of the AH, leading to elevated TOP.
One aspect of the disclosure here is a technique for active drainage of the AH via an implanted assembly that could potentially prolong the efficacy of glaucoma drainage device therapy for controlling IOP. The assembly is composed of a pump that is coupled to a passive flow structure. The pump forces the AH through the passive flow structure when activated, to thereby accelerate drainage of the AH through the passive flow structure only when it is powered directly from a wireless power transfer source that is external to the person and that is brought into proximity with the eye. There is therefore no need to implant a power source for activating the pump. In one aspect, the pump when activated forces the AH through the passive flow structure at a rate (e.g., bulk fluid flow) of 0.1 microliters/minute to 100 microliters/minute, or more particularly one to ten microliters per minute, which may be sufficient to break or to prevent the formation of scarring related fibrotic adhesions in the outflow site. Operating the pump intermittently over time, during on-demand drainage intervals, may prevent scarring at the outflow site and therefore continuously maintain a pressure drop through the passive flow structure, thereby preventing elevated TOP levels.
Another aspect of the disclosure here is an implantable assembly for managing eye disease of a person, in which there is a pharmaceutical agent flow structure and a pump that is coupled to the flow structure. The pump is configured to be activated and thereby force a pharmaceutical agent through the flow structure into the eye (e.g., a dose between ten nanoLiters to one thousand nanoLiters), only when powered directly from a wireless power transfer source that is external to the person and that is brought into proximity with the eye. This enables intermittent, on-demand delivery of the pharmaceutical agent.
The above summary does not include an exhaustive list of all aspects of the present disclosure. It is contemplated that the disclosure includes all systems and methods that can be practiced from all suitable combinations of the various aspects summarized above, as well as those disclosed in the Detailed Description below and particularly pointed out in the Claims section. Such combinations may have advantages not specifically recited in the above summary.
Several aspects of the disclosure here are illustrated by way of example and not by way of limitation in the figures of the accompanying drawings in which like references indicate similar elements. It should be noted that references to “an” or “one” aspect in this disclosure are not necessarily to the same aspect, and they mean at least one. Also, in the interest of conciseness and reducing the total number of figures, a given figure may be used to illustrate the features of more than one aspect of the disclosure, and not all elements in the figure may be required for a given aspect.
Several aspects of the disclosure with reference to the figures are now explained. Whenever the shapes, relative positions and other aspects of the parts described are not explicitly defined, the scope of the invention is not limited only to the parts shown, which are meant merely for the purpose of illustration. Also, while numerous details are set forth, it is understood that some aspects of the disclosure may be practiced without these details. In other instances, well-known circuits, structures, and techniques have not been shown in detail so as not to obscure the understanding of this description.
Note that the figure shows the wireless power transfer source 1 as being external to the person, such as part of a handheld device. In one instance, the housing of the power transfer source 1 could be attached to eyeglasses that can be worn by the person. For example, the power transfer source 1 could be integrated into a frame of the eyeglasses, or it could be joined to the frame in an easily removable manner. There is therefore no need to implant into the person an electrical power source such as a battery or a capacitor, for activating the pump 5.
Turning now to
The actuator is configured to, when energized as described further below, displace the membrane or diaphragm 4 sequentially over several cycles thereby resulting in a bulk flow of the AH, from the eye and out through the passive flow structure 3 (and into the outflow site.) There are separate ways of achieving this actuation, depending on the actuation mechanism and the type of membrane or diaphragm 4. In a first instance, the actuator when energized will drive or displace the flexible membrane or diaphragm 4 in a direction that increases the variable pump volume thereby drawing the AH into the volume through the inlet check valve 6. In a second instance, the actuator when energized will drive displace the flexible membrane or diaphragm in another direction that decreases the volume thereby forcing the AH out of the volume through the outlet check valve. In a third instance, the actuator is energized to drive or displace the flexible membrane or diaphragm in both directions to sequentially increase the volume and then decrease the volume. For example, in the case of the first instance and the second instance, the membrane or diaphragm 4 may be a diaphragm that is inherently (or otherwise) spring loaded so that it returns to a default or biased position once the pump 5 has been de-energized—in that case the pump 5 may only need to be energized in each cycle to displace the membrane or diaphragm in a single direction. In the case of the third instance, the membrane or diaphragm could be a flexible membrane and as such the pump would need to be energized in each cycle to displace the membrane in both directions sequentially.
There are various techniques for powering the pump 2, or energizing the actuator, which depend on the actuation mechanism and the way in which power is transferred from the non-implantable or external, wireless power transfer source 1 (
In another pump actuation technique (not shown), the pump 5 has an implanted element, e.g., an implanted electromagnet such as a coil with or without ferromagnetic material, which is attached to move as one with the membrane or diaphragm 4. Such a pump is activated by magnetic field interaction created by an oscillating external ferromagnet (in the wireless power transfer source 1.)
Referring now to
In another pump actuation technique (not shown), the actuator is a thermal actuator, and the pump 5 also includes an energy harvesting element (e.g., an RF coil.) The pump 5 is activated when the thermal actuator is energized by for example a suitable electronic driver circuit that is responsive to a voltage change at the output of the energy harvesting element whenever a transmitter in the wireless power transfer source 1 (e.g., an electromagnet) is energized. The thermal actuator may be one that produces mechanical displacement because of being heated based on a thermal pneumatic effect, a shape memory alloy effect, a bimetal effect, or a mechanical thermal expansion.
In still another actuation technique (not shown), the actuator is configured to produce a phase change or pneumatic expansion that expands a gas volume, e.g., hydrolyzes water to result in oxygen or hydrogen gas, which in turn produces mechanical displacement that moves the membrane or diaphragm 4. As above, the pump is activated only when its actuator is energized by the wireless power transfer source 1.
Another aspect of the disclosure here is adapting the implantable assembly 2—see
While certain aspects have been described above, and shown in the accompanying drawings, it is to be understood that such are merely illustrative of and not restrictive on the broad invention, and that the invention is not limited to the specific constructions and arrangements shown and described, since various other modifications may occur to those of ordinary skill in the art. The description is thus to be regarded as illustrative instead of limiting.
This U.S. nonprovisional patent application claims the benefit of the earlier filing date of U.S. Provisional Application No. 63/344,506, filed 20 May 2022.
| Number | Date | Country | |
|---|---|---|---|
| 63344506 | May 2022 | US |
