Determination of oxygen saturation and photosensitizer accumulation in the tumor with the help of LEDand laser diode-based irradiation sources and fiber-optics probes

2017 ◽  
Vol 1 (5) ◽  
pp. 124-126
Author(s):  
Vladimir KHOLIN
Keyword(s):  
Oxygen Saturation ◽  
Fiber Optics ◽  
Laser Diode

scholarly journals SPECTROPHOTOMETRIC DETERMINATION OF THE OXYGEN SATURATION OF WHOLE BLOOD

1955 ◽  
Vol 217 (1) ◽  
pp. 479-488
Author(s):  
Makepeace U. Tsao ◽  
Shirley S. Sethna ◽  
Charles H. Sloan ◽  
Lillian J. Wyngarden
Keyword(s):  
Oxygen Saturation ◽  
Spectrophotometric Determination ◽  
Whole Blood

Effect of subcutaneous arterial pulsation on determination of cerebral arterial oxygen saturation using NIRS

2000 ◽  
Author(s):  
Ralph J. F. Houston ◽  
Jan Menssen ◽  
Marco C. van der Sluijs ◽  
Willy N. Colier ◽  
Berend Oeseburg
Keyword(s):  
Oxygen Saturation ◽  
Arterial Oxygen Saturation ◽  
Arterial Oxygen ◽  
Arterial Pulsation

Measurement of hemoglobin oxygen saturation in capillaries

1987 ◽  
Vol 252 (5) ◽  
pp. H1031-H1040 ◽  
Author(s):  
M. L. Ellsworth ◽  
R. N. Pittman ◽  
C. G. Ellis
Keyword(s):  
Light Intensity ◽  
Oxygen Saturation ◽  
Red Blood Cells ◽  
Optical Density ◽  
Blood Cells ◽  
Striated Muscle ◽  
Cheek Pouch ◽  
Retractor Muscle ◽  
Hamster Cheek Pouch

We present a computer-aided videodensitometric method for the determination of oxygen saturation in red blood cells flowing through capillaries of the hamster cheek pouch retractor muscle. The optical density (OD) of red blood cells is determined at two wavelengths. At the first, 431 nm, there is a maximum difference between absorption by oxygen deoxyhemoglobin. At the second, 420 nm, absorption is equal for the two absorbing species (isosbestic wavelength). In capillaries of the retractor muscle a relationship between oxygen saturation (S) and the following OD ratio was obtained as S = -1.71 (OD431/OD420) + 2.20. The error (95% confidence interval) in oxygen saturation associated with a determination of the OD ratio is estimated to be +/- 4.8%. The computerization of the method employs a frame-by-frame analysis of the light intensity over a selected capillary segment. The light intensity waveform along the segment is digitized and the minimum (I) and maximum (I0) light intensities are used to compute an optical density (OD = log10 [I0/I]). These minimum and maximum intensities correspond to the presence and absence of a red blood cell, respectively. The method permits the off-line analysis of videotaped scenes and provides a means of assessing the extent of temporal and spatial heterogeneity of oxygen saturation in selected capillary networks. The method has been developed for use in capillaries in transilluminated striated muscle but should be generally applicable to the measurement of capillary oxygen saturation in other tissues.

Fiber-optic transmission catheter for regional venous oxygen saturation and blood flow

1992 ◽  
Vol 72 (4) ◽  
pp. 1616-1621 ◽  
Author(s):  
H. Iwasaki ◽  
K. Yoshizaki ◽  
H. Koyano
Keyword(s):  
Blood Flow ◽  
Oxygen Saturation ◽  
Fiber Optics ◽  
Fiber Optic ◽  
Supply And Demand ◽  
Flow Measurements ◽  
Face To Face ◽  
Flexible Polymer ◽  
Venous Oxygen Saturation ◽  
The Face

We have developed a method for monitoring regional venous oxygen saturation. The key feature of this system is the use of highly flexible polymer fiber optics, and this flexibility allowed the production of a new fiber-optic transmission catheter. The space between the “face-to-face” positioned fiber-optic tips forms a remote catheter-based transmission cell. Our method applies Twersky's theory, in which absorption and scattering can be treated independently. Fresh rabbit blood was pumped through a disk oxygenator in which gas exchange occurred and passed the catheter. Simultaneous results obtained by the catheter and a cuvette oximeter were excellent (r = 0.99, SD = 1.1%). Oxygen saturation measured by this catheter was independent of vessel wall artifacts, blood pH, and flow velocity. Another application of this method is measurement of blood flow by the dye- (indocyanine green) dilution technique. The results of flow measurements by the catheter appeared to be satisfactory (r = 0.99, SD = 1.7%). This study concludes that our method is effective for monitoring the balance between regional oxygen supply and demand.

scholarly journals The new device for determination of fiber content in individual plants of fiber flax

2019 ◽  
pp. 75-79
Author(s):  
Oleksandr Holoviy
Keyword(s):  
Laser Diode ◽  
Fiber Content ◽  
Fiber Flax ◽  
New Device

The article describes the design of the device for determining the fiber content in individual plants of flax, which is a special torsion scales of the new design. The principle of operation of the device is based on the transformation of the free end of the cantilever-mounted flat spring, to which the object of suspension is suspended, in the rotation of a mirror that reflects the laser diode beam on the scale. The device can be used in fibe flax breeding.

scholarly journals Ektacytometric measurement of sickle cell deformability as a continuous function of oxygen tension [published erratum appears in Blood 1987 Apr;69(4):1272]

Blood ◽  
1987 ◽  
Vol 69 (1) ◽  
pp. 316-323 ◽  
Author(s):  
MP Sorette ◽  
MG Lavenant ◽  
MR Clark
Keyword(s):  
Oxygen Saturation ◽  
Oxygen Tension ◽  
Sickle Cell ◽  
Hemoglobin Concentration ◽  
Exchange System ◽  
Cell Deformability ◽  
Linear Gradient ◽  
Couette Viscometer ◽  
Gas Exchange System

Abstract In an effort to study the rheologic effects of small amounts of hemoglobin S (HbS) polymer in sickle red cells, we have used the ektacytometer, a laser diffraction couette viscometer, to measure sickle cell deformability as a function of oxygen tension. Sickle cell populations of defined intracellular hemoglobin concentration (MCHC) were isolated using Stractan density gradients and were resuspended in buffered polyvinylpyrrolidone solutions for deformability measurements. Using a gas-porous, hollow fiber gas exchange system to establish a linear gradient in oxygen tension, deformability was measured over a pO2 range of 76 to 0 mm Hg. Parallel spectroscopic determinations of oxygen saturation permitted determination of cell deformability as a function of oxygen saturation for each discrete MCHC population. From these measurements the level of oxygen saturation at which a loss in cell deformability was first detected could be defined. Then, using the data of Noguchi and Schecter, the amount of polymerized HbS in the cells at that defined level of oxygen saturation was estimated. The results of this analysis suggested that the quantity of polymer that caused a detectable loss in cell deformability increased with increasing MCHC. In addition, for MCHC above 30 g/dL, this represented a substantial fraction of the total HbS in the cell.

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