Reflective non-contact ocular pulse analyzer for clinical diagnosis of eye and cerebrovascular disease

• US 20080242965A1
• Filed: 03/21/2008
• Published: 10/02/2008
• Est. Priority Date: 03/26/2007
• Status: Active Grant

• Current Assignee: Nuseon, LLC
• Original Assignee: Nuseon, LLC
• Inventors: Norris, John Lawrence, Allison, Robert W.
• Granted Patent: US 8,740,795 B2
• Time in Patent Office: Days
• US Class Current: 600/398
• CPC Class Codes: A61B 3/16 for measuring intraocular pressure, e.g. tonometers
• CPC Class Codes: A61B 3/165 Non-contacting tonometers

Abstract

An instrument has been designed to study the pulsatile motion of the eye by analysis of a beam of light reflected from the corneal surface. A laser light beam probe of small spot size and low divergence strikes the cornea apex and the reflected movement is recorded by a sensor. Analysis of the beam movement reveals the energy in the eye pulse without the necessity of physically touching the eye. The value of the intraocular pressure is determined from the calculated power spectrum. The sensitivity, accuracy and efficiency of the light beam makes possible studying both eyes concurrently and comparison of the pulse parameters of onset, amplitude and duration reveals any delay in circulation to an eye.

Claims

1. An ocular pulse analyzer for measuring an eye intraocular pressure and blood flow comprising:

a an optic head for measuring the displacement of the eye front surface during the ocular pulse comprising;

1 a beam forming module comprising a laser diode, a beam expander with an internal spatial filter, a shaper collimator and dump, and a turning mirror means for forming a small diameter low divergence light beam probe that strikes the apex of the cornea at a large incidence and is reflected

2 a reflected beam line module comprising a turning mirror, beam quadrature error detector, ccd camera array means for detecting beam errors and forming a pixelated image of the reflected beam spot width

3 a patient and operator module comprising an optical eye fixation target, and a ccd camera video port means for eye fixation and aligning and observing the measurement

b a digital control and data acquisition module comprising blood pressure sensors, digital and analog converters, a computer, display, and real time control panel means for controlling the optical head and acquiring the ocular pulse data.2

2. A method for a magnifying non contact high resolution measurement of the ocular pulse waveform eye surface motion comprising reflection of a large angle incident beam from the axis of symmetry of the curved corneal apex due to changes in the corneal curvature and the angle of incidence as the surface moves.