US5219400A
Expired / Lapsed
US
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Noninvasive method for quantitation of oxyhemoglobin saturation by near-infrared reflectance spectrophotometry
Assignee: United States Department of the Army
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Filing: 1991-06-11
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Granted: 1993-06-15
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Expires: 2011-06-11
Abstract
Abstract The degree of hemoglobin oxygenation in the blood vessels of the retina isetermined under conditions of dark-adaptation and light-adaptation by directing a beam of near-infrared light having a range of wavelengths from 700 to 100 nanometers at a blood vessel in the retina, measuring the intensity of the backscattered light from the blood vessel in the range from 700 to 800 nanometers at regularly spaced intervals of wavelength, such as 2 nanometers, and determining the degree of hemoglobin oxygenation by reference to a correlation between hemoglobin oxygen and light absorbance in the near-infrared spectral range.
Inventors
- 👤 Jorge L. Jacot
- 👤 John T. O'Neill
- 👤 Lou Reinisch
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-03 21:17
CPC Classifications
A; A61; A61B; A61B5/00; A61B5/145; A61B5/1455; A61B5/14551; A61B5/14555; A61B3/00; A61B3/10
Claims Analysis
Total Claims: 7
Claim 1
Independent Claim
116 words
A noninvasive method of determining the degree of oxygenation of hemoglobin in the blood vessels of the retina comprising directing a beam of light in a broad range of wavelengths in the near-infrared spectral range into an eye through the pupil, focussed upon a blood vessel in the retina; measuring the intensity of backscattered light from the blood vessel in a narrow range of wavelengths in the near-infrared spectral range; and determining the degree of oxygenation of hemoglobin in the blood vessel by reference to a correlation derived from validation tests between the intensity of the backscattered light from the blood vessel and the degree of oxygenation of hemoglobin in the blood vessel in the retina.
Claim 2
Dependent Claim
116 words
A noninvasive method of determining the degree of oxygenation of hemoglobin in the blood vessels of the retina comprising directing a beam of light in a broad range of wavelengths in the near-infrared spectral range into an eye through the pupil, focussed upon a blood vessel in the retina; measuring the intensity of backscattered light from the blood vessel in a narrow range of wavelengths in the near-infrared spectral range; and determining the degree of oxygenation of hemoglobin in the blood vessel by reference to a correlation derived from validation tests between the intensity of the backscattered light from the blood vessel and the degree of oxygenation of hemoglobin in the blood vessel in the retina.
Claim 3
Dependent Claim
18 words
The method of claim 1 in which the broad range of wavelengths is from 700 to 1000 namometers.
Claim 4
Dependent Claim
18 words
The method of claim 1 in which the narrow range of wavelengths is from 700 to 800 nanometers.
Claim 5
Dependent Claim
29 words
The method of claim 1 in which the intensity of the backscattered light from the blood vessel is measured at predetermined intervals of wavelength from 0.5 to 3 namometers.
Claim 6
Dependent Claim
28 words
The method of claim 1 in which the intensity of the backscattered light from the blood vessel is measured at predetermined intervals of wavelength of about 2 namometers.
Claim 7
Dependent Claim
42 words
The method of claim 1 in which the correlation is derived from in vitro and in vivo measurements of the intensity of light scattered in the narrow range of wavelength by a glass capillary containing blood of known degree of hemoglobin oxygenation.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1996-06-14 | 1996-12-14 | 1997-06-15 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2000-06-14 | 2000-12-14 | 2001-06-15 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2004-06-14 | 2004-12-14 | 2005-06-15 | $7700.00 | Window Closed / Lapsed |