scholarly journals Evaluation of the Effect of Hypercapnia on Vascular Function in Normal Tension Glaucoma

2015 ◽  
Vol 2015 ◽  
pp. 1-11 ◽  
Author(s):  
B. Quill ◽  
E. Henry ◽  
E. Simon ◽  
C. J. O’Brien
Keyword(s):  
Blood Flow ◽  
Vascular Function ◽  
Normal Tension Glaucoma ◽  
Ocular Blood Flow ◽  
Thermal Stimulus ◽  
Lower Baseline ◽  
Cardiovascular Assessment ◽  
And Gender ◽  
End Tidal ◽  
High Responders

Introduction. Altered ocular perfusion and vascular dysregulation have been reported in glaucoma. The aim of this paper was to evaluate the vascular response to a hypercapnic stimulus.Methods. Twenty normal tension glaucoma (NTG) patients and eighteen age- and gender-matched controls had pulsatile ocular blood flow (POBF) measurements, systemic cardiovascular assessment, and laser Doppler digital blood flow (DBF) assessed. Measurements were taken at baseline, after 10-minutes rest, in the stable sitting and supine positions and following induction and stabilization of hypercapnia, which induced a 15% increase in end-tidalpCO2. The POBF response to hypercapnia was divided into high (>20%) and low responders (<20%).Results. 65% of NTG patients had a greater than 41% increase in POBF followingCO2rebreathing (high responders). These high responders had a lower baseline POBF, lower baseline DBF, and a greater DBF response to thermal stimulus.Conclusion. NTG patients that have a greater than 20% increase in POBF after a hypercapnic stimulus have lower baseline POBF and DBF values. This suggests that there is impaired regulation of blood flow in a significant subgroup of NTG patients. This observation may reflect a generalised dysfunction of the vascular endothelium.

scholarly journals Association of ocular blood flow and contrast sensitivity in normal tension glaucoma

2021 ◽  
Author(s):  
David Kuerten ◽  
Matthias Fuest ◽  
Peter Walter ◽  
Babac Mazinani ◽  
Niklas Plange
Keyword(s):  
Blood Flow ◽  
Visual Field ◽  
Contrast Sensitivity ◽  
Visual Field Defect ◽  
Prospective Trial ◽  
Normal Tension Glaucoma ◽  
Ocular Blood Flow ◽  
Retinal Blood Flow ◽  
Control Group ◽  
Field Defect

Abstract Purpose To investigate the relationship of ocular blood flow (via arteriovenous passage time, AVP) and contrast sensitivity (CS) in healthy as well as normal tension glaucoma (NTG) subjects. Design Mono-center comparative prospective trial Methods Twenty-five NTG patients without medication and 25 healthy test participants were recruited. AVP as a measure of retinal blood flow was recorded via fluorescein angiography after CS measurement using digital image analysis. Association of AVP and CS at 4 spatial frequencies (3, 6, 12, and 18 cycles per degree, cpd) was explored with correlation analysis. Results Significant differences regarding AVP, visual field defect, intraocular pressure, and CS measurement were recorded in-between the control group and NTG patients. In NTG patients, AVP was significantly correlated to CS at all investigated cpd (3 cpd: r =  − 0.432, p< 0.03; 6 cpd: r =  − 0.629, p< 0.0005; 12 cpd: r =  − 0.535, p< 0.005; and 18 cpd: r =  − 0.58, p< 0.001), whereas no significant correlations were found in the control group. Visual acuity was significantly correlated to CS at 6, 12, and 18 cpd in NTG patients (r =  − 0.68, p< 0.002; r =  − 0.54, p< .02, and r =  − 0.88, p< 0.0001 respectively), however not in healthy control patients. Age, visual field defect MD, and PSD were not significantly correlated to CS in in the NTG group. MD and PSD were significantly correlated to CS at 3 cpd in healthy eyes (r = 0.55, p< 0.02; r =  − 0.47, p< 0.03). Conclusion Retinal blood flow alterations show a relationship with contrast sensitivity loss in NTG patients. This might reflect a disease-related link between retinal blood flow and visual function. This association was not recorded in healthy volunteers.

The association between systemic oxidative stress and ocular blood flow in patients with normal-tension glaucoma

2015 ◽  
Vol 254 (2) ◽  
pp. 333-341 ◽  
Author(s):  
Noriko Himori ◽  
Hiroshi Kunikata ◽  
Yukihiro Shiga ◽  
Kazuko Omodaka ◽  
Kazuichi Maruyama ◽  
...  
Keyword(s):  
Oxidative Stress ◽  
Blood Flow ◽  
Normal Tension Glaucoma ◽  
Ocular Blood Flow ◽  
Systemic Oxidative Stress

scholarly journals Acute and Chronic Periocular Massage for Ocular Blood Flow and Vision: a Randomized Controlled Trial

2021 ◽  
Vol 14 (2) ◽  
pp. 5-13
Author(s):  
Naoyuki Hayashi, PhD ◽  
Lanfei Du, MSc
Keyword(s):  
Blood Flow ◽  
Visual Acuity ◽  
Vascular Function ◽  
Controlled Trial ◽  
Ocular Blood Flow ◽  
Control Group ◽  
Long Term Effects ◽  
Short Term ◽  
Before And After

Introduction: The ocular blood flow (OBF) is responsible for supplying nutrition to the retina, which plays a fundamental role in visual function. Massage is expected to improve the blood flow and, consequently, vascular function. The aim of this study was to determine the shortterm and long-term effects of periocular massage on OBF and visual acuity. Methods: The OBF and visual acuity were measured in 40 healthy adults aged 20–30 years before and after massage, and also in control subjects. Three massage methods were used: applying periocular acupressure (“Chinese eye exercise”: CE), using a facial massage roller (MR), and using an automated eye massager (AM). The OBF and visual acuity were first measured before and after applying each type of massage for 5 min. Eye massage was then applied for 5 min once daily over a 60-day period, while the control group received no massage. The same measurements were then performed again. Results: Performing short-term periocular massage showed significant interactions in time and massage effects on visual acuity in CE and AM groups, and on OBF in AM group, while 60-day massage period exerted no significant effects. No significant relationship was found between OBF and visual acuity changes. Conclusions: These results suggest that short-term periocular massage with Chinese eye exercise and automated eye massager can improve OBF and visual acuity, although no causal relationship was supported.

Four Years Later: A Clinical Update on Latanoprost

2003 ◽  
Vol 13 (2) ◽  
pp. 162-175 ◽  
Author(s):  
E. Ravinet ◽  
A. Mermoud ◽  
R. Brignoli
Keyword(s):  
Blood Flow ◽  
Open Angle Glaucoma ◽  
Cataract Extraction ◽  
Normal Tension Glaucoma ◽  
Ocular Blood Flow ◽  
Ciliary Muscle ◽  
Angle Closure ◽  
Pigmentary Glaucoma ◽  
Long Term Treatment ◽  
Pulsatile Ocular Blood Flow

Purpose Almost five years have elapsed since the introduction of latanoprost on several markets and considering the large number of publications dealing with it, the authors felt that it was worth re-evaluating the drug. Methods The criterion used to select trials for inclusion in the review was: all articles mentioning the drug in common electronic data-bases; these were then screened and considered, on the basis of methodological quality. Results Experimental data suggest that latanoprost acts by remodeling the extracellular matrix in the ciliary muscle, thus increasing the flow of aqueous humor through the ciliary muscle bundles of the uveoscleral pathway. POAG Latanoprost persistently improves the pulsatile ocular blood flow in primary open angle glaucoma (POAG). Recent trials confirmed the greater IOP-lowering efficacy of latanoprost vs. timolol, dorzolamide, brimonidine and unoprostone. Trials lasting up to 24 months showed that latanoprost is effective in long-term treatment of POAG and ocular hypertension (OH), with no signs of loss of efficacy when compared to timolol or dorzolamide. Latanoprost provides better control of circadian IOP. Non-responders to b-blockers should preferably be switched to latanoprost monotherapy before a combination therapy is started. The possibility of a fixed combination of latanoprost and timolol has been explored, with promising results. NTG Latanoprost is effective in normal tension glaucoma (NTG), lowering IOP, improving pulsatile ocular blood flow and increasing ocular perfusion pressure. Other Glaucomas Latanoprost may provide effective IOP control in angle-closure glaucoma after iridectomy, in pigmentary glaucoma, glaucoma after cataract extraction and steroid-induced glaucoma. However, latanoprost was effective in only a minority of pediatric cases of glaucoma and is contraindicated in all forms of uveitic glaucoma. Safety In the articles reviewed, new or duration-related adverse events were reported.

scholarly journals Cyclooxygenase inhibition abolishes age-related differences in cerebral vasodilator responses to hypercapnia

2012 ◽  
Vol 112 (11) ◽  
pp. 1884-1890 ◽  
Author(s):  
Jill N. Barnes ◽  
John E. Schmidt ◽  
Wayne T. Nicholson ◽  
Michael J. Joyner
Keyword(s):  
Blood Flow ◽  
Vascular Function ◽  
Cerebral Blood Flow Velocity ◽  
Cerebrovascular Reactivity ◽  
Cyclooxygenase Inhibition ◽  
Healthy Humans ◽  
Age Related ◽  
Before And After ◽  
End Tidal ◽  
Cerebral Vasodilator

Blood flow and vasodilatory responses are altered by age in a number of vascular beds, including the cerebral circulation. To test the role of prostaglandins as regulators of cerebral vascular function, we examined cerebral vasodilator responses to CO2 (cerebrovascular reactivity) in young (26 ± 5 yr; 6 males/6 females) and older (65 ± 6 yr, 5 males/5 females) healthy humans before and after cyclooxygenase inhibition (using indomethacin). Middle cerebral artery velocity (MCAv) responses to stepped hypercapnia were measured before and 90 min after indomethacin. Changes in MCAv during the recovery from hypercapnia (vasoconstrictor responses) were also evaluated before and after indomethacin. Cerebrovascular reactivity was calculated using linear regression between MCAv and end-tidal CO2. Young adults demonstrated greater MCAv (55 ± 6 vs. 39 ± 5 cm/s: P < 0.05) and MCAv reactivity (1.67 ± 0.20 vs. 1.09 ± 0.19 cm·s−1·mmHg−1; P < 0.05) to hypercapnia compared with older adults ( P < 0.05). In both groups MCAv and MCAv reactivity decreased between control and indomethacin. Furthermore, the age-related differences in these cerebrovascular variables were abolished by indomethacin. During the recovery from hypercapnia, there were no age-related differences in MCAv reactivity; however, indomethacin significantly reduced the MCAv reactivity in both groups. Taken together, these results suggest that cerebral blood flow velocity and cerebrovascular reactivity are attenuated in aging humans, and may be due to a loss of prostaglandin-mediated vasodilation.

Waveform Analysis of Ocular Blood Flow and the Early Detection of Normal Tension Glaucoma

2013 ◽  
Vol 54 (12) ◽  
pp. 7699 ◽  
Author(s):  
Yukihiro Shiga ◽  
Kazuko Omodaka ◽  
Hiroshi Kunikata ◽  
Morin Ryu ◽  
Yu Yokoyama ◽  
...  
Keyword(s):  
Blood Flow ◽  
Early Detection ◽  
Normal Tension Glaucoma ◽  
Ocular Blood Flow ◽  
Waveform Analysis
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