Tonometer & method of use

• US 20030097052A1
• Filed: 11/20/2002
• Published: 05/22/2003
• Est. Priority Date: 11/21/2001
• Status: Active Grant

• Current Assignee: Ahmed A. Mateen
• Original Assignee: Ahmed A. Mateen
• Inventors: Ahmed, A. Mateen
• Granted Patent: US 6,923,765 B2
• Time in Patent Office: Days
• US Class Current: 600/399
• CPC Class Codes: A61B 3/16 for measuring intraocular pressure, e.g. tonometers

Abstract

A device used to measure intraocular pressure within a patient'"'"'s eye includes a probe typically having an end to which is attached a resilient member with a hollow interior that decreases in volume as the member is pressed against the eye. The greater the intraocular pressure within an eye, the more the volume decreases. A liquid moves in response to this change and this movement is detected to signal if the intraocular pressure is at a safe level.

Claims

1. A device for measuring the intraocular pressure within an eye, including

a probe having a bulbous-like end made of a flexible, resilient material and adapted to contact the eye, said bulbous-like end having a hollow interior,

a chamber within the probe including the hollow interior of the bulbous-like end and a conduit extending from the hollow interior of the bulbous-like end along the probe, said chamber being at least partially filled with a fluid,

said fluid moving within said chamber in response to the hollow interior of the bulbous-like end changing in volume as it bears against the eye, and

a detector responsive to the movement of the fluid in the conduit to provide a signal indicating the intraocular pressure.

2. The device of claim 1 where the fluid includes a liquid having two immiscible phases, one phase being non-conductive and the other phase being conductive.

3. The device of claim 2 including

a first electrical connection at a first position along the conduit and a second electrical connection at a second position along the conduit,

said conductive phase making contact with the first electrical connection to complete a first electrical circuit when the conductive phase of the liquid reaches said first position when the intraocular pressure is at a first pressure, and

said conductive phase making contact with the second electrical connection to complete a second electrical circuit when the conductive phase of the liquid reaches said second position when the intraocular pressure is at a second pressure.

4. The device of claim 3 where the second pressure is higher than the first pressure.

5. The device of claim 1 including a stop member that restricts the movement of the probe.

6. The device of claim 1 where the signal provides an indication that the intraocular pressure is at a safe level or above a safe level.

7. A device for measuring the intraocular pressure within an eye, including

a probe comprising a pair of arms pivotally connected at proximal ends of the arms, each arm having a distal end adapted to make contact with the eye and one of said distal ends having a pressure transducer thereat for detecting intraocular pressure,

a stop member that limits the distance the distal ends may be moved manually towards each other to apply essentially the same external pressure against the eye with each measurement of intraocular pressure, and

a detector responsive to the transducer that provides a signal indicating the intraocular pressure.

8. The device of claim 7 where the transducer comprises

a bulbous-like member made of a flexible, resilient material and adapted to contact the eye, said bulbous-like member having a hollow interior,

a chamber within the arm carrying the pressure transducer, said chamber including the hollow interior of the bulbous-like member and a conduit extending from the hollow interior of the bulbous-like member along said arm carrying the pressure transducer, said chamber being at least partially filled with a liquid,

said liquid moving within said chamber in response to the hollow interior of the bulbous-like member changing in volume as said bulbous-like member bears against the eye.

9. The device of claim 8 where the liquid has two immiscible phases, one phase being non-conductive and the other phase being conductive.

10. The device of claim 9 including

a first electrical connection at a first position along the conduit and a second electrical connection at a second position along the conduit,

said conductive phase making contact with the first electrical connection to complete a first electrical circuit when the conductive phase of the liquid reaches said first position when the intraocular pressure is at a first pressure, and

said conductive phase making contact with the second electrical connection to complete a second electrical circuit when the conductive phase of the liquid reaches said second position when the intraocular pressure is at a second pressure.

11. The device of claim 10 where the second pressure is higher than the first pressure.

12. A device for measuring the intraocular pressure within an eye, including

a probe having an elongated arm member with an end to which is attached a bulbous-like member, said bulbous-like member being made of a flexible, resilient material and adapted to contact the eye, said bulbous-like member having a hollow interior that decreases in volume as the bulbous-like member is pressed against the eye, the greater the intraocular pressure within an eye the more said volume decreases,

a chamber in the arm including the hollow interior of the bulbous-like member and a conduit extending from the hollow interior of the bulbous-like member along the arm, said chamber being at least partially filled with a liquid having two immiscible phases, one phase being non-conductive and the other phase being conductive,

a stop member that, when said bulbous-like member is pressed against the eye, restricts the movement of the probe,

a first electrical connection at a first position along the conduit and a second electrical connection at a second position along the conduit,

said conductive phase making contact with the first electrical connection to complete a first electrical circuit when the conductive phase of the liquid reaches said first position when the intraocular pressure is at a first pressure, and

said conductive phase making contact with the second electrical connection to complete a second electrical circuit when the conductive phase of the liquid reaches said second position when the intraocular pressure is at a second pressure, and

a detector responsive to the movement of the conductive phase of the liquid to said first and second positions in the conduit that provides a first signal indicating the intraocular pressure is at a safe level when the conductive phase of the liquid is at the first position and a second signal indicating the intraocular pressure is at an unsafe level when the conductive phase of the liquid is at the second position.

13. The device of claim 12 where the probe includes a second arm pivotally connected to the arm carrying the bulbous-like member and the stop member is disposed between said arms.

14. A device for measuring and recording the intraocular pressure within an eye of a patient, including

a probe having at a distal end a pressure transducer for detecting intraocular pressure, said pressure transducer providing an analog signal corresponding to the patient'"'"'s intraocular pressure upon the probe contacting the eye of the patient,

an analog to digital converter that converts the analog signal into a digital signal corresponding to the patient'"'"'s current measurement of intraocular pressure,

a memory device that stores information concerning said patient, including past measurements of the patient'"'"'s intraocular pressure,

a display device for displaying at least some of the information concerning said patient, including at least one past measurement of the patient'"'"'s intraocular pressure and the current measurement of intraocular pressure, and

a microprocessor for processing the digital signal corresponding to the patient'"'"'s current measurement of intraocular pressure and forwarding said current measurement of intraocular pressure to the memory device and forwarding a past and the current measurement of intraocular pressure to the display device.

15. The device of claim 14 where the transducer comprises

a bulbous-like member made of a flexible, resilient material and adapted to contact the eye, said bulbous-like member having a hollow interior,

a chamber within the probe, said chamber including the hollow interior of the bulbous-like member and a conduit extending from the hollow interior of the bulbous-like member along said probe, said chamber being at least partially filled with a liquid,

said liquid moving within said chamber in response to the hollow interior of the bulbous-like member changing in volume as said bulbous-like member bears against the eye.

16. The device of claim 15 where the liquid has two immiscible phases, one phase being non-conductive and the other phase being conductive.

17. The device of claim 16 including

a first electrical connection at a first position along the conduit and a second electrical connection at a second position along the conduit,

said conductive phase making contact with the first electrical connection to complete a first electrical circuit when the conductive phase of the liquid reaches said first position when the intraocular pressure is at a first pressure, and

said conductive phase making contact with the second electrical connection to complete a second electrical circuit when the conductive phase of the liquid reaches said second position when the intraocular pressure is at a second pressure.

18. The device of claim 17 where the second pressure is higher than the first pressure.

19. A device for measuring the intraocular pressure within an eye, including

a probe comprising a pair of arms,

each arm having a proximal end and a distal end adapted to make contact with the eye, said proximal ends being pivotally connected together and manually moveable towards each other,

one of said distal ends having thereat a bulbous-like member adapted to contact the eye and made of a flexible, resilient material, said bulbous-like member having a hollow interior,

a chamber within the arm carrying a bulbous-like member, said chamber including the hollow interior of the bulbous-like member and a conduit extending from the hollow interior of the bulbous-like member along said arm carrying the bulbous-like member,

said chamber being filled with liquid and a non-conductive compressible gas, said liquid having two immiscible phases, one phase being non-conductive and the other phase being conductive, the non-conductive phase at least partially filling the hollow interior of the bulbous-like member and the conductive liquid phase being between the non-conductive liquid phase and the non-conductive gas phase,

in response to the arms being moved towards each other, said liquid moving within said chamber in response to the hollow interior of the bulbous-like member changing in volume as said bulbous-like member bears against the eye to move the conductive liquid phase along the conduit and cause the gas to compress,

at a proximal end of one of the arms stop member that limits the distance the distal ends may be moved manually towards each other,

a spring member responsive to the movement to the arms that goes into compression upon the arms being manually moved towards each other, said spring normally moving the arms apart,

a first electrical connection at a first position along the conduit and a second electrical connection at a second position along the conduit,

said conductive liquid phase making contact with the first electrical connection to complete a first electrical circuit when the conductive phase of the liquid reaches said first position when the intraocular pressure is at a first pressure,

said conductive phase making contact with the second electrical connection to complete a second electrical circuit when the conductive phase of the liquid reaches said second position when the intraocular pressure is at a second pressure, said second pressure being higher than said first pressure, and

a display device connected to the first and second electrical circuits, said display device providing a first visual signal indicating that the intraocular pressure is at a safe level when the first electrical circuit is completed and providing a second visual signal indicating that the intraocular pressure is above a safe level when the second electrical circuit is completed.

20. The device of claim 19 including an audio alarm that is activated when the arms are moved towards each other to a position where said distal ends are spaced apart a predetermined distance.

21. A device for measuring the intraocular pressure within an eye, including

a probe having an elongated, substantially straight arm member with an end to which is attached a bulbous-like member, said bulbous-like member being made of a flexible, resilient material and adapted to contact the eye,

said bulbous-like member having a hollow interior that decreases in volume as the bulbous-like member is pressed against the eye, the greater the intraocular pressure within an eye the more said volume decreases,

a chamber in the arm including the hollow interior of the bulbous-like member and a conduit extending from the hollow interior of the bulbous-like member along the arm, said chamber being at least partially filled with a liquid having two immiscible phases, one phase being non-conductive and the other phase being conductive,

a first electrical connection at a first position along the conduit and a second electrical connection at a second position along the conduit,

said conductive phase making contact with the first electrical connection point to complete a first electrical circuit when the conductive phase of the liquid reaches said first position when the intraocular pressure is at a first pressure, and

said conductive phase making contact with the second electrical connection to complete a second electrical circuit when the conductive phase of the liquid reaches said second position when the intraocular pressure is at a second pressure, and

a detector responsive to the movement of the conductive phase of the liquid to said first and second positions in the conduit that provides a first signal indicating the intraocular pressure is at a safe level when the conductive phase of the liquid is at the first position and a second signal indicating the intraocular pressure is at an unsafe level when the conductive phase of the liquid is at the second position.

22. A method of measuring intraocular pressure through the closed eyelid of a patient, comprising the steps of contacting the closed eye lid with a probe having a bulbous-like end made of a flexible, resilient material and a hollow interior, said probe including

a chamber comprising the hollow interior of the bulbous-like end and a conduit extending from the hollow interior of the bulbous-like end along the probe, said chamber being at least partially filled with a fluid,

said fluid moving within said chamber in response to the hollow interior of the bulbous-like end changing in volume as it bears against the eye, and

a detector responsive to the movement of the fluid in the conduit to provide a signal indicating the intraocular pressure.

23. The method of claim 22 where the movement of the probe is limited.

24. The method of claim 23 where the probe comprises a pair of arms having distal and proximal ends, said proximal ends being pivotally connected.

25. The method of claim 23 including a stop member that insures that the arms are moved towards each other so that their distal ends are spaced apart a predetermined distance upon engaging the stop member.

26. A method of detecting if the intraocular pressure within an eye is at a safe level comprising

contacting eye with an end of a probe to which is attached a resilient member with a hollow interior that decreases in volume as the member is pressed against the eye, said interior including a liquid that moves in response to this change in volume, and

detecting this movement to determine if the intraocular pressure is at a safe level and providing a signal indicating if at a safe or unsafe level.