Directional contrast and observation of retinal arterial retrograde blood flow in out-of-plane vessels with laser Doppler holography

2021 ◽  
Author(s):  
Léo Puyo ◽  
Michel Paques ◽  
Michael Atlan
Keyword(s):  
Blood Flow ◽  
Laser Doppler ◽  
Out Of Plane ◽  
Retrograde Blood Flow

scholarly journals Retinal blood flow reversal quantitatively monitored in out-of-plane vessels with laser Doppler holography

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Léo Puyo ◽  
Michel Paques ◽  
Michael Atlan
Keyword(s):  
Blood Flow ◽  
Color Doppler ◽  
Laser Doppler ◽  
Retinal Blood Flow ◽  
Doppler Imaging ◽  
Doppler Spectrum ◽  
High Temporal Resolution ◽  
Directional Information ◽  
Out Of Plane ◽  
Flow Reversals

AbstractLaser Doppler holography is a planar blood flow imaging technique recently introduced in ophthalmology to image human retinal and choroidal blood flow non-invasively. Here we present a digital method based on the Doppler spectrum asymmetry that reveals the local direction of blood flow with respect to the optical axis in out-of-plane vessels. This directional information is overlaid on standard grayscale blood flow images to depict flow moving towards the camera in red and flow moving away from the camera in blue, as in ultrasound color Doppler imaging. We show that thanks to the strong contribution of backscattering to the Doppler spectrum in out-of-plane vessels, the local axial direction of blood flow can be revealed with a high temporal resolution, which enables us to evidence pathological blood flow reversals. We also demonstrate the use of optical Doppler spectrograms to quantitatively monitor retinal blood flow reversals.

Peculiarities of microcirculation in periodont tissues in children of key age groups sufficient type 1 diabetes. Part II

2019 ◽  
Vol 24 (2) ◽  
pp. 108-119 ◽  
Author(s):  
B. N. Davydov ◽  
D. A. Domenyuk ◽  
S. V. Dmitrienko
Keyword(s):  
Diabetes Mellitus ◽  
Blood Flow ◽  
Type 1 Diabetes ◽  
Type 1 Diabetes Mellitus ◽  
Laser Doppler Flowmetry ◽  
Laser Doppler ◽  
Diabetic Microangiopathy ◽  
Healthy Children ◽  
Doppler Flowmetry

Relevance. Morpho-functional changes in peripheral circulation established in type 1 diabetes mellitus correlate with changes in central hemodynamics, allowing the use of microcirculation indicators as diagnostic and prognostic criteria for assessing the degree of functional vascular disorders. Identifcation of microcirculation features of the blood by the method of laser Doppler flowmetry in children with different experience of type 1 diabetes in key age categories.Materials and methods. The study included 67 children with type 1 diabetes mellitus aged 12-15 years with an experience of the disease from six months to ten years. The comparison group consisted of 38 healthy children. The state of the microvasculature was assessed by laser Doppler flowmetry using a laser analyzer for capillary blood flow LAKK-OP.Results. In children with an experience of type 1 diabetes of less than two years, microcirculation disorders in periodontal tissues correspond to the hyperemic form, accompanied by increased perfusion, a decrease in the amplitude of low-frequency oscillations, increased heart rate, high blood flling, and blood flow bypass. For children with an endocrinopathy experience of more than three years, microcirculation disorders correspond to a stagnant form, combined with a decrease in perfusion due to stagnation of blood in the venular link, endothelial domination with suppression of neurogenic and cardiac fluctuations, low efciency and redistribution of blood flow in favor of the nutritive link.Conclusions. With the increase in experience, the degree of compensation of type 1 diabetes, the progression of diabetic microangiopathy, it is advisable to designate two stages of development of microcirculatory disorders. Early – compensatory with active adaptation, including neurogenic and endothelial regulation mechanisms. Late – decompensation with passive adaptation, supporting the effectiveness of microcirculation due to myogenic control of regulation, shunting and increasing the rate of blood outflow.

scholarly journals Laser Doppler blood flowmeter as a useful instrument for the early detection of lower extremity peripheral arterial disease in hemodialysis patients: an observational study

2019 ◽  
Vol 20 (1) ◽  
Author(s):  
Takeo Ishii ◽  
Shizuka Takabe ◽  
Yuki Yanagawa ◽  
Yuko Ohshima ◽  
Yasuhiro Kagawa ◽  
...  
Keyword(s):  
Blood Flow ◽  
Peripheral Arterial Disease ◽  
Early Stage ◽  
Arterial Disease ◽  
Hemodialysis Patients ◽  
Laser Doppler ◽  
Doppler Flowmetry ◽  
Skin Perfusion ◽  
Dorsal Area ◽  
Peripheral Arterial

Abstract Background A simpler method for detecting atherosclerosis obliterans is required in the clinical setting. Laser Doppler flowmetry (LDF) is easy to perform and can accurately detect deterioration in skin perfusion. We performed LDF for hemodialysis patients to determine the correlations between blood flow in the lower limbs and peripheral arterial disease (PAD). Methods This retrospective study included 128 hemodialysis patients. Patients were categorized into the non-PAD group (n = 106) and PAD group (n = 22), 14 early stage PAD patients were included in the PAD group. We conducted LDF for the plantar area and dorsal area of the foot and examined skin perfusion pressure (SPP) during dialysis. Results SPP-Dorsal Area values were 82.1 ± 22.0 mmHg in the non-PAD, and 59.1 ± 20.3 mmHg in PAD group, respectively (p < 0.05). The LDF-Plantar blood flow (Qb) values were 32.7 ± 15.5 mL/min in non-PAD group and 21.5 ± 11.3 mL/min in PAD group (p < 0.001). A total of 21 non-PAD patients underwent LDF before and during dialysis. The LDF-Plantar-Qb values were 36.5 ± 17.6 mL/min before dialysis and 29.6 ± 17.7 mL/min after dialysis (p < 0.05). We adjusted SPP and LDF for PAD using logistic regression, SPP-Dorsal-Area and LDF-P were significantly correlated with PAD (p < 0.05). The receiver-operating characteristic curve analysis indicated cut-off values of 20.0 mL/min for LDF-Plantar-Qb during dialysis. Conclusion LDF is a simple technique for sensitive detection of early-stage PAD. This assessment will help physicians identify early-stage PAD, including Fontaine stage II in clinical practice, thereby allowing prompt treatment.

scholarly journals Exercise and Repeated Testing Improves Accuracy of Laser Doppler Assessment of Microvascular Function Following Shortened (1-minute) Blood Flow Occlusion

2016 ◽  
Vol 23 (4) ◽  
pp. 293-300 ◽  
Author(s):  
Brian D. Tran ◽  
Abraham Chiu ◽  
Charlene Tran ◽  
Danica Rose Rogacion ◽  
Nicole Tfaye ◽  
...  
Keyword(s):  
Blood Flow ◽  
Microvascular Function ◽  
Laser Doppler ◽  
Repeated Testing ◽  
Blood Flow Occlusion ◽  
Flow Occlusion

Evaluating Blood Flow in Full-Thickness Skin Grafts Utilizing the Laser Doppler

1989 ◽  
Vol 15 (11) ◽  
pp. 1178-1183 ◽  
Author(s):  
MICHAEL J. MULVANEY ◽  
STUART J. SALASCHE ◽  
WILLIAM J. GRABSKI
Keyword(s):  
Blood Flow ◽  
Laser Doppler ◽  
Skin Grafts ◽  
Full Thickness ◽  
Full Thickness Skin ◽  
Thickness Skin
Sign in / Sign up

Export Citation Format

Share Document