Reactions of skin microvessels to limb blood flow changes studied by photoplethysmography and laser doppler flow

1989 ◽  
Vol 107 (5) ◽  
pp. 711-714
Author(s):  
E. V. Oschepkova ◽  
A. N. Rogoza ◽  
V. V. Panfilov
Keyword(s):  
Blood Flow ◽  
Laser Doppler ◽  
Limb Blood Flow ◽  
Laser Doppler Flow ◽  
Doppler Flow ◽  
Flow Changes

Laser-Doppler determination of papillary blood flow in young and adult rats

1986 ◽  
Vol 251 (1) ◽  
pp. F115-F124 ◽  
Author(s):  
R. J. Roman ◽  
C. Smits
Keyword(s):  
Blood Flow ◽  
Dorsal Surface ◽  
Laser Doppler ◽  
Laser Doppler Flowmeter ◽  
Adult Rats ◽  
Laser Doppler Flow ◽  
Doppler Flow ◽  
Vasa Recta ◽  
Highly Correlated ◽  
Doppler Flowmeter

Renal hemodynamics and renal blood flow autoregulatory ability differ in young (body wt 100 g) and adult (body wt 300 g) rats. Possible age-dependent changes in inner medullary hemodynamics have not been examined because it has not been possible to expose the papilla of adult rats for direct study of the vasa recta circulation. This study presents a technique for exposure of the papilla in any size rat. Seven days before an acute experiment, a small amount of cortical tissue overlying the papilla on the dorsal surface of the kidney was removed. The creation of this papillary window allowed for exposure of the papilla in adult rats after removal of the ureter. Using this preparation, we compared papillary blood flow in young and adult rats using a Periflux differential laser-Doppler flowmeter (Perimed, Stockholm, Sweden). The meter was calibrated by comparing the signal obtained from the papilla of 28 rats with papillary flow measured from the accumulation of 51Cr-labeled erythrocytes in the papilla. The laser-Doppler flow signal was linearly related and highly correlated (r = 0.92) to the red cell flow into the papilla. Comparisons of laser-Doppler flow signals obtained from the papilla of young and adult animals indicated that papillary blood flow was approximately 2-fold greater in the adult rats than in the young animals. This finding was associated with an enhanced maximal urine concentrating ability found in the younger rats. These studies demonstrate the utility of the laser-Doppler flowmeter for the assessment of papillary blood flow and suggest that inner medullary hemodynamics differ in young and adult rats.

Outcomes of dental fracture injury as related to laser Doppler flow measurements of pulpal blood-flow level

2008 ◽  
Vol 24 (4) ◽  
pp. 416-421 ◽  
Author(s):  
Rdiger Emshoff ◽  
Ivano Moschen ◽  
Andreas Oberrauch ◽  
Stefan Gerhard ◽  
Heinrich Strobl
Keyword(s):  
Blood Flow ◽  
Laser Doppler ◽  
Flow Measurements ◽  
Laser Doppler Flow ◽  
Doppler Flow ◽  
Pulpal Blood Flow

scholarly journals Effect of Kampo Medicines on the Peripheral Blood Flow Rate of Betamethason-Induced Oketsu Syndrome Mice by Laser Doppler Flow Meter

2004 ◽  
Vol 124 (6) ◽  
pp. 365-369 ◽  
Author(s):  
Joji UEDA ◽  
Etsuko OHYA ◽  
Kozue UDAGAWA ◽  
Akiko HARA ◽  
Mai FUKUI ◽  
...  
Keyword(s):  
Blood Flow ◽  
Flow Rate ◽  
Peripheral Blood ◽  
Blood Flow Rate ◽  
Laser Doppler ◽  
Peripheral Blood Flow ◽  
Flow Meter ◽  
Laser Doppler Flow ◽  
Doppler Flow

scholarly journals Simultaneous Measurements of Pial Arteriolar Diameter and Laser-Doppler Flow during Somatosensory Stimulation

1995 ◽  
Vol 15 (1) ◽  
pp. 124-127 ◽  
Author(s):  
Al C. Ngai ◽  
Joseph R. Meno ◽  
H. Richard Winn
Keyword(s):  
Blood Flow ◽  
Sciatic Nerve ◽  
Laser Doppler ◽  
Similar Response ◽  
Somatosensory Stimulation ◽  
Laser Doppler Flow ◽  
Cortical Blood Flow ◽  
Doppler Flow ◽  
Cranial Window ◽  
Arteriolar Diameter

We simultaneously measured pial arteriolar diameter and changes in cortical blood flow during activation of the somatosensory cortex by sciatic nerve stimulation. The pial vasculature was visualized with a closed-cranial window technique in chloralose-anesthetized rats ( n = 13). Local blood flow was monitored with laser-Doppler flowmetry. During stimulation of the sciatic nerve (0.2 V, 5 Hz, 20 s), vascular diameter and laser-Doppler flow consistently displayed similar response profiles. With 0.5-ms stimulation pulses, the responses showed an initial peak followed by a smaller but sustained plateau dilation. In contrast, 5-ms pulses evoked a monotonically rising response. Our results support the concept that pial arteriolar diameter changes reflect cortical blood flow responses during somatosensory stimulation.

Pulpal blood flow recorded from human premolar teeth with a laser Doppler flow meter using either red or infrared light

2011 ◽  
Vol 56 (7) ◽  
pp. 629-633 ◽  
Author(s):  
Kanittha Kijsamanmith ◽  
Siriporn Timpawat ◽  
Noppakun Vongsavan ◽  
Bruce Matthews
Keyword(s):  
Blood Flow ◽  
Laser Doppler ◽  
Infrared Light ◽  
Flow Meter ◽  
Laser Doppler Flow ◽  
Doppler Flow ◽  
Pulpal Blood Flow

Evaluation of laser-Doppler flowmetry as a measure of tissue blood flow

1986 ◽  
Vol 61 (2) ◽  
pp. 666-672 ◽  
Author(s):  
G. J. Smits ◽  
R. J. Roman ◽  
J. H. Lombard
Keyword(s):  
Blood Flow ◽  
Laser Doppler Flowmetry ◽  
Electromagnetic Flowmeter ◽  
Laser Doppler ◽  
Tissue Blood Flow ◽  
Organ Blood Flow ◽  
Doppler Flowmetry ◽  
Laser Doppler Flow ◽  
Doppler Flow

In this study the technique of laser-Doppler flowmetry was evaluated for the measurement of tissue blood flow by comparing laser-Doppler flow (LDF) signal in the renal cortex, gracilis muscle, and cremaster muscle of anesthetized rats to whole-organ blood flow measured with an electromagnetic flowmeter or radioactive microspheres. In vitro, LDF signal was closely correlated (r = 0.99) to changes in erythrocyte velocity generated with a rotating wheel. Although individual LDF readings varied in situ, mean LDF signal calculated from multiple readings on the tissue surface were significantly correlated (r = 0.74–0.95) with tissue blood flows measured at various perfusion pressures. However, significant differences in the slope of the LDF signal vs. blood flow relationship were observed in different tissues and with different methods of measurement in the same tissue. This study indicates that mean laser-Doppler flow signal provides a good estimate of tissue blood flow, provided a sufficient number of points is scanned. However, there appears to be no universal calibration factor for the method.

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