Ocular blood flow in dogs was monitored loith the use of a specially designed photoelectric plethysmograph transducer. The ocular pulse waves demonstrated were (1) of low amplitude, (2) coincident with cardiac systole, and (3) rapidly affected by stimuli known to influence cerebral blood flow. Changes in ocidar pulse amplitude correlated ivith concurrent blood gas analyses (arterial COi and O!)...

BACKGROUND AND PURPOSE Ocular pulse amplitude, the amplitude of the ocular pneumoplethysmographic waveform, is altered in several ophthalmologic diseases that disturb ocular blood flow, implying that ocular pulse amplitude may provide an estimate of ocular blood flow. Because ocular blood flow currently cannot be quantified in humans, two experiments were undertaken to evaluate the association ...

Pulsatile ocular blood flow, intraocular pressure, systemic blood pressure, and heart rate was measured in two groups of 15 patients. One received lignocaine 1.5 mgtkg intravenously prior to induction. There was a significant increase in intraocular pressure after suxamethonium, which was not associated with any rise in ocular blood flow. Both the IOP and ocular blood flow increased significant...

The effects of sympathetic tone on ocular blood flow have not been adequately studied in the past. Recent experimental work has contradicted earlier observations. We have used nuclidelabeled microspheres to measure the intraocular blood flow. The results of the study demonstrate that the ocular vascular beds are responsive to sympathetic tone. Cervical sympathectomy increased ocular blood flow,...

AIMS To investigate the source of ocular blood flow alterations in glaucoma. METHODS In 56 patients with open angle glaucoma, blood flow parameters were obtained from both eyes in the ophthalmic and central retinal artery by means of colour Doppler imaging, as well as in the choroidal circulation and the neuroretinal rim of the optic nerve by means of laser Doppler flowmetry. Based on these h...

The hypothesis that heat stress reduces the ocular blood flow response to exhaustive exercise was tested by measuring ocular blood flow, blood pressure, and end- tidal carbon dioxide partial pressure (PETCO2) in 12 healthy males while they performed cycle ergometer exercise at 75% of the maximal heart rate at ambient temperatures of 20°C (control condition) and 35°C (heat condition), until exha...

Glaucoma may be caused by an interplay of elevated intraocular pressure (IOP), vascular, genetic, anatomical, brain, and immune factors. The direct assessment of ocular hemodynam-ics offers promise for glaucoma detection, differentiation, and possibly new treatment modalities. All the methods currently in use to measure ocular blood flow have inherent limitations and measure different aspects o...

Myopia is the most common refractive error and the subject of interest of various studies assessing ocular blood flow. Increasing refractive error and axial elongation of the eye result in the stretching and thinning of the scleral, choroid, and retinal tissues and the decrease in retinal vessel diameter, disturbing ocular blood flow. Local and systemic factors known to change ocular blood flow...