Implant having MEMS flow module with movable, flow-controlling baffle
Various embodiments of MEMS flow modules that may be disposed in a flow path ( 296 ) of a shunt ( 290 ) are disclosed, where the shunt ( 290 ) may be used to control a flow out of an anterior chamber ( 284 ) of an eye ( 266 ). One such MEMS flow module ( 58 ) has a tuning element ( 78 ) and a lower plate ( 70 ). A plurality of springs or spring-like structures ( 82 ) interconnect the tuning element ( 78 ) with the lower plate ( 70 ) in a manner that allows the tuning element ( 78 ) to move either toward or away from the lower plate ( 70 ), depending upon the pressure being exerted on the tuning element ( 78 ) by a flow through a lower flow port ( 74 ) on the lower plate ( 70 ). The tuning element ( 78 ) is disposed over this lower flow port ( 74 ) to induce a flow through the MEMS flow module ( 58 ) along a non-linear (geometrically) flow path.
1. An implant for addressing pressure within a first body region, said implant comprising:
a conduit comprising a flow path and adapted to fluidly interconnect with the first body region; and
a MEMS flow module disposed within said flow path, wherein said MEMS flow module comprises:
a flow regulator, wherein said flow regulator comprises a first baffle; and
a first plate, wherein said first plate comprises a first flow port, wherein said first baffle is aligned with said first flow port, and wherein said first baffle is movable relative to said first plate to change a magnitude of a spacing of said first baffle from said first plate in response to a change in differential pressure across said MEMS flow module;
wherein the first plate comprises a first group of a plurality of the first flow ports and wherein the first baffle is aligned with each first flow port in the first group; and
wherein said first baffle comprises a plurality of baffle flow ports, wherein said plurality of first flow ports in said first group and said plurality of baffle flow ports are arranged such that a flow through any given said first flow port must change direction to flow through any of said plurality of baffle flow ports.
2. An implant, as claimed in claim 1 , wherein: said first baffle is movable along an axis that corresponds with a direction of a flow entering said MEMS flow module through said first flow port.
3. An implant, as claimed in claim 1 , wherein: said first baffle is always disposed in spaced relation to said first plate.
4. An implant, as claimed in claim 1 , further comprising: at least one spring movably interconnecting said first baffle with said first plate.
5. An implant, as claimed in claim 1 , further comprising: a plurality of springs movably interconnecting said first baffle with said first plate.
6. An implant, as claimed in claim 1 , further comprising: a first flow channel defined by a space between said first baffle and said first plate, wherein at least a portion of said flow entering said MEMS flow module through said first flow port flow passes through said first flow channel before exiting said MEMS flow module.
7. An implant, as claimed in claim 1 , wherein: during any movement of said first baffle relative to said first plate, a distance between said first baffle and said first plate is proportional across an entire extent of said first baffle.
8. An implant, as claimed in claim 1 , wherein: all flow though any of said first flow ports in said first group is required to proceed around a perimeter of said first baffle.
9. An implant, as claimed in claim 1 , wherein: said first baffle is disposed to change a direction of said flow entering said MEMS flow module through said first flow port before said flow exits said MEMS flow module.
10. An implant, as claimed in claim 9 , wherein: said flow entering said MEMS flow module exerts a normal force on said first baffle.
11. An implant, as claimed in claim 1 , wherein: said MEMS flow module is a passive device.
12. An implant, as claimed in claim 1 , wherein: the first body region is an anterior chamber of an eye.
13. An implant for addressing pressure within a first body region, said implant comprising:
a conduit comprising a flow path and adapted to fluidly interconnect with the first body region; and
a MEMS flow module disposed within said flow path, wherein said MEMS flow module comprises:
a flow regulator, wherein said flow regulator comprises a first baffle; and
a first plate, wherein said first plate comprises a first flow port, wherein said first baffle is aligned with said first flow port, and wherein said first baffle is movable relative to said first plate to change a magnitude of a spacing of said first baffle from said first plate in response to a change in differential pressure across said MEMS flow module; and
means for limiting a maximum amount of movement of said first baffle away from said first flow port.
14. An implant, as claimed in claim 13 , wherein: said first baffle comprises a plurality of baffle flow ports, wherein said plurality of first flow ports in said first group and said plurality of baffle flow ports are arranged such that a flow through any given said first flow port must change direction to flow through any of said plurality of baffle flow ports.
15. An implant, as claimed in claim 13 , wherein said MEMS flow module further comprises a plurality of said first baffles and at least one spring separately interconnecting each said first baffle with said first plate, wherein at least one said first flow port is associated with each said first baffle.
16. An implant, as claimed in claim 13 , further comprising: at least one spring movably interconnecting said first baffle and said first plate; a second plate comprising a second flow port and that is spaced from said first baffle, wherein said first baffle is located between said first and second plates, and wherein at least a portion of said flow that enters said MEMS flow module through said first flow port exits said MEMS flow module through said second flow port; and an annular support interconnecting said first and second plates, wherein said first plate, said second plate, and said annular support collectively define an enclosed space.
17. An implant, as claimed in claim 16 , wherein: said second plate comprises at least one overpressure stop aligned with said first baffle.
18. An implant for addressing pressure within a first body region, said implant comprising:
a conduit comprising a flow path and adapted to fluidly interconnect with the first body region; and
a MEMS flow module disposed within said flow path, wherein said MEMS flow module comprises:
a flow regulator, wherein said flow regulator comprises a first baffle; and
a first plate, wherein said first plate comprises a first flow port, wherein said first baffle is aligned with said first flow port, and wherein said first baffle is movable relative to said first plate to change a magnitude of a spacing of said first baffle from said first plate in response to a change in differential pressure across said MEMS flow module;
wherein: said first baffle exists at least in a first fabrication level and said first plate exists at least in a second fabrication level that is spaced from said first fabrication level.
19. An implant, as claimed in claim 18 , wherein: a position of said first baffle within said MEMS flow module is dependent upon a pressure being exerted on said first baffle by a flow entering said MEMS flow module through said first flow port, wherein a flow rate of said flow exiting said MEMS flow module is dependent upon a position of said first baffle within said MEMS flow module, and wherein said first baffle changes a direction of said flow entering said MEMS flow module through said first flow port before said flow exits said MEMS flow module.
20. An implant, as claimed in claim 18 ,
wherein: said first baffle moves relative to said first plate so as to provide greater than a proportional increase in a flow rate out of said MEMS flow module for an increase in differential pressure across said MEMS flow module.
21. An implant, as claimed in claim 18 ,
wherein: a position of said first baffle is dependent upon a pressure being exerted on said first baffle by said flow entering said MEMS flow module through said first flow port, and wherein a flow rate of said flow exiting said MEMS flow module is dependent upon a position of said first baffle.
22. An implant, as claimed in claim 21 , wherein said first baffle is movably suspended beyond said first plate and in overlying relation to said first flow port, wherein a spacing between said first baffle and said first plate defines a first flow channel, wherein a flow entering said MEMS flow module through said first flow port is forced by said first baffle to proceed through said first flow channel, and wherein a magnitude of said spacing between said first baffle and said first plate is variable and dependent upon a pressure being exerted on said first baffle by said flow entering said MEMS flow module through first flow port.
23. An implant, as claimed in claim 18 ,
wherein: said first baffle is in contact with said first plate until a certain differential pressure across said MEMS flow module is reached.
24. An implant, as claimed in claim 18 , further comprising: a first housing associated with said MEMS flow module, wherein said first housing and said MEMS flow module are collectively disposed within said flow path.
25. An implant, as claimed in claim 24 , further comprising: a self-assembled monolayer coating on all surfaces of said first housing that may be exposed to a biological material or a biological fluid when said implant is installed.
26. An implant, as claimed in claim 25 , wherein: said self-assembled monolayer coating is poly-ethylene-glycol.
27. An implant for addressing pressure within a first body region, said implant comprising:
a conduit comprising a flow path and adapted to fluidly interconnect with the first body region; and
a MEMS flow module disposed within said flow path, wherein said MEMS flow module comprises:
a flow regulator, wherein said flow regulator comprises a first baffle; and
a first plate, wherein said first plate comprises a first flow port, wherein said first baffle is aligned with said first flow port, and wherein said first baffle is movable relative to said first plate to change a magnitude of a spacing of said first baffle from said first plate in response to a change in differential pressure across said MEMS flow module;
a self-assembled monolayer coating on all surfaces of said MEMS flow module that may be exposed to a biological material or a biological fluid when said implant is installed.
28. A tunable shunt for permitting flow of fluid from between an anterior chamber of an eye and an exterior of the eye, the shunt comprising:
a housing adapted to be implanted, at least in part, in the eye;
a conduit disposed within the housing and defining a flow path; and
a MEMS flow module disposed within the flow path, wherein the MEMS flow module further includes:
a flow regulator having a first baffle; and
a first plate defining a first flow port;
wherein the first baffle is aligned with the first flow port, and
wherein the first baffle is movable relative to the first plate in response to a change in differential pressure across said MEMS flow module; and
wherein a position of the first baffle is dependent upon a pressure being exerted on the first baffle by the flow entering the MEMS flow module through the first flow port, and
wherein a flow rate of the flow exiting said MEMS flow module is dependent upon a position of the first baffle;
wherein the first baffle exists at least in a first fabrication level and the first plate exists at least in a second fabrication level that is spaced from the first fabrication level.
29. The tunable shunt set forth in claim 28 wherein the first baffle is always disposed in spaced relation to the first plate.
30. The tunable shunt set forth in claim 28 wherein the first baffle is in contact with the first plate until a certain differential pressure across the MEMS flow module is reached.
31. The tunable shunt set forth in claim 28 further comprising at least one spring operably interconnected with the first baffle and the first plate.
32. The tunable shunt set forth in claim 28 wherein the first plate further defines a plurality of first flow ports and wherein the flow regulator comprises a plurality of first baffles, wherein at least one of the first baffles is aligned with at least one of the first flow ports such that flow through such first flow port must change direction.
33. The tunable shunt set forth in claim 28 further comprising means for limiting the maximum amount of movement of the first baffle away from the first flow port.
34. The tunable shunt set forth in claim 28 further comprising:
a second plate defining a second flow port and connected to the first plate such that the baffle is disposed between the first plate and the second plate;
at least one spring operably interconnected with the first baffle and the first plate; and
means for limiting the maximum amount of movement of the first baffle away from the first flow port;
wherein the first plate further defines a plurality of first flow ports and wherein the flow regulator comprises a plurality of first baffles;
wherein at least one of the first baffles is aligned with at least one of the first flow ports such that flow through such first flow port must change direction; and
wherein the first baffle exists at least in a first fabrication level and the first plate exists in a second fabrication level that is spaced from the first fabrication level; and
wherein the first baffle moves relative to the first plate so as to provide greater than a proportional increase in a flow rate out of the MEMS flow module for an increase in differential pressure across the MEMS flow module.
35. The tunable shunt of claim 28 further comprising a biocompatible coating on at least portions of the MEMS flow module.