BACKGROUND Cutaneous laser Doppler flowmetry enables monitoring of changes in skin perfusion by quantifying the phase shift of laser light induced by moving red blood cells under a fiberoptic probe. It thus can identify the presence of and response to a vasoconstrictive stimulus. However, aspects of the technique must be defined before it can be used with maximum effectiveness. We evaluated the...

BACKGROUND Intra-operative flow measurement during coronary or peripheral bypass operations is helpful for ruling out technical failures and for prediction of complication and patency rates. Preclinical validation of the flowmeters is required in order to rely on the intra-operatively measured results. The aim of this study is to evaluate a new "dual beam Doppler" blood flowmeter before clinica...

Ophthalmic artery blood flow in 5 patients with internal carotid artery occlusion of sudden onset was monitored by an ultrasonic Doppler flowmeter to investigate the possible relationship to spontaneous recanalization of the occluded artery. The occluded internal carotid arteries of 2 patients were confirmed angiographically to recanalize and the reversed flow of their ophthalmic arteries chang...

The purpose of this study was to validate a two-dimensional range-gated Doppler echocardiographic method for measurement of pulmonary and systemic blood flow in a canine model with a surgically created extracardiac systemic-to-pulmonary shunt, the size of which could be varied. In five anesthetized open-chest dogs, a previously calibrated electromagnetic (EM) flowmeter was placed around the asc...

Background: The mechanisms underlying cerebral hypercapnic vasodilatation are not fully understood. Objective: To investigate the role of nitric oxide (NO) and ATP-sensitive potassium (KATP) channels in basal blood flow regulation and hypercapnia-induced vasodilatation in rabbit cerebral blood vessels. Methods: The change in cerebral blood flow was measured by a laser Doppler flowmeter in 18 Ne...

Beta-2 adrenoceptors in blood vessels are one of the active factors that play a role in regulation of tissue blood flow. in diabetic angiopathy, responsiveness of these receptors is decreased, while that is increased in inflammation. According to these opposite effects, the aim of this study was to investigate the vasodilatory response of knee joint blood vessels to salbutamol (Beta-2 adreno...

OBJECTIVE To investigate the origin of signals from scanning laser Doppler flowmetry (SLDF) and the influence of axial scan depth on the measurement of blood flow in the rat retina. METHODS We performed SLDF in 5 adult Sprague-Dawley rats using a specially modified Heidelberg retina flowmeter. Axial scans were obtained from +2 diopters (D) to -3 D (in steps of 0.25 D) or from +1 D to -2 D (in...

AIM To compare the interocular and intraocular differences of capillary perfusion, and the intraocular regional differences of retinal blood flow in the macular area of healthy volunteers. METHODS Tissue blood flow in the macula was examined in both eyes of 20 healthy volunteers with the Heidelberg retinal flowmeter. Blood flow measurements were made in a 10 degrees x 2.5 degrees area superio...