scholarly journals Laser-doppler evaluation of the human tympanic membrane by measuring blood flow, volume, and velocity

1997 ◽  
Vol 49 (2) ◽  
Author(s):  
Louise Das ◽  
Hari Cohly ◽  
William Reno ◽  
Debjyoti Goswami ◽  
Suman K. Das
Keyword(s):  
Blood Flow ◽  
Tympanic Membrane ◽  
Laser Doppler ◽  
Flow Volume ◽  
Blood Flow Volume ◽  
Doppler Evaluation ◽  
Human Tympanic Membrane

Blood flow, volume, and transit time in the pulmonary microvasculature using laser-Doppler

1994 ◽  
Vol 76 (6) ◽  
pp. 2643-2650 ◽  
Author(s):  
T. S. Hakim ◽  
E. Gilbert ◽  
E. M. Camporesi
Keyword(s):  
Blood Flow ◽  
Blood Volume ◽  
Transit Time ◽  
Flow Rate ◽  
Venous Pressure ◽  
Laser Doppler ◽  
Flow Volume ◽  
Doppler Flowmetry ◽  
Blood Flow Volume ◽  
Wide Range

Capillary transit time is determined by the ratio of capillary volume to flow rate. Exercise-induced hypoxemia is thought to occur because of the short transit time of erythrocytes in capillaries. The effect of flow rate on capillary volume (recruitment vs. distension) is controversial. In a perfused left lower lobe preparation in canine lungs, we used laser-Doppler flowmetry (model ALF21R) to monitor changes in blood flow, volume, and transit time in the microvasculature near the subpleural surface. Changes in total flow, blood volume, and total transit time (tt) were also measured. The results showed that microvascular volume approached maximum when flow rate was at resting value (0.4 l/min) and pressure in the pulmonary artery was > 6 mmHg relative to the level of the capillaries. In contrast, the total blood volume increased gradually over a wide range of flow rates. When flow increased 4.2 times (from 155 to 650 ml/min), tt decreased from 7.32 to 3.53 s; meanwhile, microvascular flow increased from 6.0 to 12.7 units and microvascular transit time decreased from 3.14 to 1.81 units. The changes in microvascular volume and transit time were essentially independent of whether the venous pressure was higher or lower than alveolar pressure. At very high flow (6–10 times resting value), tt fell gradually to approximately 1 s. Direct monitoring of transit time with the laser-Doppler also revealed a gradual decline in microvascular transit time as flow rate increased from 2 to 10 times the normal flow. (ABSTRACT TRUNCATED AT 250 WORDS)

Microvascular Blood Flow, Volume, and Velocity Measured by Laser Doppler Techniques in IDDM

Diabetes ◽  
1989 ◽  
Vol 38 (7) ◽  
pp. 819-824 ◽  
Author(s):  
M. Rendell ◽  
T. Bergman ◽  
G. O'Donnell ◽  
E. Drobny ◽  
J. Borgos ◽  
...  
Keyword(s):  
Blood Flow ◽  
Laser Doppler ◽  
Microvascular Blood Flow ◽  
Flow Volume ◽  
Blood Flow Volume ◽  
Doppler Techniques

Microvascular blood flow, volume, and velocity measured by laser Doppler techniques in IDDM

Diabetes ◽  
1989 ◽  
Vol 38 (7) ◽  
pp. 819-824 ◽  
Author(s):  
M. Rendell ◽  
T. Bergman ◽  
G. O'Donnell ◽  
E. Drobny ◽  
J. Borgos ◽  
...  
Keyword(s):  
Blood Flow ◽  
Laser Doppler ◽  
Microvascular Blood Flow ◽  
Flow Volume ◽  
Blood Flow Volume ◽  
Doppler Techniques

scholarly journals Determination of Blood Flow Volume of Skin by a Laser Doppler Method : Development of a New Data Analysis System

1992 ◽  
Vol 62 (10) ◽  
pp. 470-474
Author(s):  
Hiroshi Sugihara ◽  
Toyohiro Matui ◽  
Nobuyoshi Narita ◽  
Tutomu Kamo ◽  
Kimihiro Yoneyama ◽  
...  
Keyword(s):  
Blood Flow ◽  
Data Analysis ◽  
Method Development ◽  
Laser Doppler ◽  
Flow Volume ◽  
Doppler Method ◽  
Blood Flow Volume ◽  
Analysis System ◽  
Data Analysis System

scholarly journals P07.04: Uterine artery blood flow volume is reduced in human pregnancies with increase utero-placental downstream impedance

2006 ◽  
Vol 28 (4) ◽  
pp. 569-569
Author(s):  
S. Boito ◽  
S. Rigano ◽  
G. Pennati ◽  
L. Mandia ◽  
A. Padoan ◽  
...  
Keyword(s):  
Blood Flow ◽  
Uterine Artery ◽  
Flow Volume ◽  
Artery Blood Flow ◽  
Blood Flow Volume

Cerebral Blood Flow Volume in Posterior Circulation Ischemic Disorders

2021 ◽  
pp. 154431672110539
Author(s):  
Anastasiya Yu. Vishnyakova ◽  
Nataliya M. Medvedeva ◽  
Alexander B. Berdalin ◽  
Svetlana E. Lelyuk ◽  
Vladimir G. Lelyuk
Keyword(s):  
Blood Flow ◽  
Healthy Volunteers ◽  
Internal Carotid ◽  
Duplex Sonography ◽  
Posterior Circulation ◽  
Control Group ◽  
Vertebrobasilar Insufficiency ◽  
Flow Volume ◽  
Blood Flow Volume ◽  
Vertebral Arteries

Objective: The aim of this study was to determine blood flow volume (BFV) in the normal state and its features in patients with acute posterior circulation ischemic strokes (PCIS) and vertebrobasilar insufficiency (VBI) using color duplex sonography (DS).Methods: The study included DS data from 96 patients with verified PCIS (66 men and 30 women, aged 64±13 years) and 29 adults with VBI (17 men and 12 women, aged 66±11 years). The control group consisted of 65 healthy male volunteers of different ages.Results: In asymptomatic healthy volunteers, there was a significant decrease in BFV in the internal carotid artery (ICA) with age (502 ml/min in young people, 465 ml/min in the older subgroup) with rS = −0.24 ( p = 0.05), and the aggregated BFV in the vertebral arteries (VAs) turned out to be almost constant (141–143 ml/min). In patients with VBI, the aggregated BFV in the VAs (144 ml/min) did not differ from that in healthy volunteers, but the BFV values in the ICAs were significantly lower (325 ml/min). In patients with PCIS, the aggregated BFV in the ICAs was also significantly lower (399 ml/min) than in the control group but did not significantly differ from that in patients with VBI. In patients with PCIS, there was a significant decrease in the aggregated BFV in the VAs (105 ml/min), which distinguished this group from other examined patients.Conclusions: A significant decrease the BFV in the VA was observed only in patients with PCIS and was associated with the presence of steno-occlusive diseases (SOD) more often in the left VA. Patients with VBI had the most pronounced decrease in BFV in the ICA.

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