Ocular Perfusion (ocular + perfusion)

Distribution by Scientific Domains

Terms modified by Ocular Perfusion

  • ocular perfusion pressure

  • Selected Abstracts


    Ocular perfusion and age-related macular degeneration

    ACTA OPHTHALMOLOGICA, Issue 2 2001
    Thomas A. Ciulla
    ABSTRACT. Purpose: To review the role of ocular perfusion in the pathophysiology of age-related macular degeneration (AMD), the leading cause of irreversible blindness in the industrialized world. Methods: Medline search of the literature published in English or with English abstracts from 1966 to 2000 was performed using various combinations of relevant key words. Results: Vascular defects have been identified in both nonexudative and exudative AMD patients using fluorescein angiographic methods, laser Doppler flowmetry, indocyanine green angiography, and color Doppler imaging. Conclusion: Although these studies lend some support to the vascular pathogenesis of AMD, it is not possible to determine if the choroidal perfusion abnormalities play a causative role in nonexudative AMD, if they are simply an association with another primary alteration, such as a primary RPE defect or a genetic defect at the photoreceptor level, or if they are more strongly associated with one particular form of this heterogeneous disease. Further study is warranted. [source]


    Epilepsy Patients Treated with Antiepileptic Drug Therapy Exhibit Compromised Ocular Perfusion Characteristics

    EPILEPSIA, Issue 11 2002
    Emma J. Roff Hilton
    Summary: ,Purpose: Reduced cerebral blood flow and decreased cerebral glucose metabolism have been identified in patients with epilepsy treated with antiepileptic drug (AED) therapy. The purpose of this study was to determine whether ocular haemodynamics are similarly reduced in patients with epilepsy treated with AEDs. Methods: Scanning laser Doppler flowmetry was used to measure retinal capillary microvascular flow, volume, and velocity in the temporal neuroretinal rim of 14 patients diagnosed with epilepsy (mean age, 42.0 ▒ 0.9 years). These values were compared with those of an age- and gender-matched normal subject group (n = 14; mean age, 41.7 ▒ 0.3 years). Student's unpaired two-tailed t tests were used to compare ocular blood-flow parameters between the epilepsy and normal subject groups (p < 0.05; Bonferroni corrected). Results: A significant reduction in retinal blood volume (p = 0.001), flow (p = 0.003), and velocity (p = 0.001) was observed in the epilepsy group (13.52 ▒ 3.75 AU, 219.14 ▒ 76.61 AU, and 0.77 ▒ 0.269 AU, respectively) compared with the normal subject group (19.02 ▒ 5.11 AU, 344.03 ▒ 93.03 AU, and 1.17 ▒ 0.301 AU, respectively). Overall, the percentage mean difference between the epilepsy and normal groups was 36.31% for flow, 28.92% for volume, and 34.19% for velocity. Conclusions: Patients with epilepsy exhibit reduced neuroretinal capillary blood flow, volume, and velocity compared with normal subjects. A reduction in ocular perfusion may have implications for visual function in people with epilepsy. [source]


    A double masked placebo controlled study on the effect of nifedipine on optic nerve blood flow and visual field function in patients with open angle glaucoma

    BRITISH JOURNAL OF CLINICAL PHARMACOLOGY, Issue 2 2001
    Georg Rainer
    Aims, To investigate whether nifedipine affects ocular perfusion or visual fields in open angle glaucoma patients. Methods, In a parallel group study nifedipine or placebo was administered for 3 months (n = 30). Ocular fundus pulsation amplitude (FPA), cup blood flow (Flowcup) and visual field mean deviation (MD) were measured. Results, Five patients receiving nifedipine discontinued due to adverse events. Nifedipine did not affect FPA [difference: 0.3 Ám (95% CI ,0.3,0.9); P = 0.70], Flowcup: [difference: ,9 rel.units (95% CI ,133,114); P = 0.99], or MD [difference: 0.2dB (95% CI ,2.2,2.7); P = 0.51]vs placebo. Conclusions, Systemic nifedipine is not well tolerated in glaucoma patients and exerts no effect on visual fields or ocular perfusion. [source]


    Ocular haemodynamic changes after single treatment with photodynamic therapy assessed with non-invasive techniques

    ACTA OPHTHALMOLOGICA, Issue 6 2009
    Noemi Maar
    Abstract. Purpose:, To investigate in patients with neovascular age-related macular degeneration (ARMD) the changes in ocular perfusion caused by single treatment with photodynamic therapy (PDT) by different non-invasive methods; to evaluate correlations between relative changes of ocular haemodynamic parameters after PDT among each other and compared to morphological parameters; and to assess this in relation to early changes of visual acuity. Methods:, Study population: 17 consecutive patients with subfoveal choroidal neovascularization (CNV) caused by ARMD scheduled for PDT without previous PDT treatment (four patients with predominantly classic CNV and 13 patients with occult CNV). Observation procedures: best-corrected visual acuity (before PDT, 6 and 8 weeks after PDT), fundus photography, fluorescein angiography, haemodynamic measurements with laser Doppler flowmetry (LDF), laser interferometry and ocular blood flow (OBF) tonometry (baseline and 1, 2, 6 and 8 weeks after treatment). Main outcome measures: choroidal blood flow (CHBF), fundus pulsation amplitude (FPA), pulsatile ocular blood flow (POBF), visual acuity. Changes smaller than 20% were considered clinically irrelevant. Results:, Ocular haemodynamic parameters did not change significantly in the follow-up period. Changes of haemodynamic parameters showed no correlation to treatment spot, morphological changes or visual acuity. Changes of visual acuity were comparable to results of earlier studies. Conclusion:, Single treatment with PDT did not modify ocular blood flow parameters above 20% as assessed with different non-invasive methods. [source]


    Impact of medication on ocular blood flow

    ACTA OPHTHALMOLOGICA, Issue 2009
    L SCHMETTERER
    Purpose Reduced ocular blood flow appears to play a role in the pathophysiology of glaucoma. Hence, there is considerable interest in drugs that are capable of improving ocular perfusion. Methods A large numer of clinical trials have been performed investigating the ocular hemodynamic effects of topical and systemic medications. Such trials used a variety of different methods to assess ocular blood flow parameters. Results When adminsitered systemically most vasodilators decrease systemic blood pressure thereby reducing ocular perfusion pressure (OPP). Only few classes of drugs have been reported to increase ocular blood flow with no or minimal effect on OPP. Among these carbonic anhydrase inhibitors and endothelin receptor anatgonists show the most prononced ocular vasodilator effects. The ocular hemodynamoic effects of topical medications is generally considered small. Conclusion When drugs are given systemically the effects on OPP have to be considered. In addition, the potentially positive effects on ocular perfusion need to be carefully weighed against the side effects. With topically administered drugs the ocular hemodynamic effects will be generally small, because the drugs reach the posterior pole of the eye in small concentrations only. [source]


    Ocular perfusion and age-related macular degeneration

    ACTA OPHTHALMOLOGICA, Issue 2 2001
    Thomas A. Ciulla
    ABSTRACT. Purpose: To review the role of ocular perfusion in the pathophysiology of age-related macular degeneration (AMD), the leading cause of irreversible blindness in the industrialized world. Methods: Medline search of the literature published in English or with English abstracts from 1966 to 2000 was performed using various combinations of relevant key words. Results: Vascular defects have been identified in both nonexudative and exudative AMD patients using fluorescein angiographic methods, laser Doppler flowmetry, indocyanine green angiography, and color Doppler imaging. Conclusion: Although these studies lend some support to the vascular pathogenesis of AMD, it is not possible to determine if the choroidal perfusion abnormalities play a causative role in nonexudative AMD, if they are simply an association with another primary alteration, such as a primary RPE defect or a genetic defect at the photoreceptor level, or if they are more strongly associated with one particular form of this heterogeneous disease. Further study is warranted. [source]