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Hernandez RJ, Madhusudhan S, Zheng Y, El-Bouri WK. Linking Vascular Structure and Function: Image-Based Virtual Populations of the Retina. Invest Ophthalmol Vis Sci 2024; 65:40. [PMID: 38683566 PMCID: PMC11059806 DOI: 10.1167/iovs.65.4.40] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2023] [Accepted: 04/02/2024] [Indexed: 05/01/2024] Open
Abstract
Purpose This study explored the relationship among microvascular parameters as delineated by optical coherence tomography angiography (OCTA) and retinal perfusion. Here, we introduce a versatile framework to examine the interplay between the retinal vascular structure and function by generating virtual vasculatures from central retinal vessels to macular capillaries. Also, we have developed a hemodynamics model that evaluates the associations between vascular morphology and retinal perfusion. Methods The generation of the vasculature is based on the distribution of four clinical parameters pertaining to the dimension and blood pressure of the central retinal vessels, constructive constrained optimization, and Voronoi diagrams. Arterial and venous trees are generated in the temporal retina and connected through three layers of capillaries at different depths in the macula. The correlations between total retinal blood flow and macular flow fraction and vascular morphology are derived as Spearman rank coefficients, and uncertainty from input parameters is quantified. Results A virtual cohort of 200 healthy vasculatures was generated. Means and standard deviations for retinal blood flow and macular flow fraction were 20.80 ± 7.86 µL/min and 15.04% ± 5.42%, respectively. Retinal blood flow was correlated with vessel area density, vessel diameter index, fractal dimension, and vessel caliber index. The macular flow fraction was not correlated with any morphological metrics. Conclusions The proposed framework is able to reproduce vascular networks in the macula that are morphologically and functionally similar to real vasculature. The framework provides quantitative insights into how macular perfusion can be affected by changes in vascular morphology delineated on OCTA.
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Affiliation(s)
- Rémi J. Hernandez
- Liverpool Centre for Cardiovascular Science, University of Liverpool and Liverpool Heart and Chest Hospital, Liverpool, United Kingdom
- Department of Cardiovascular and Metabolic Medicine, Institute of Life Course and Medical Sciences, University of Liverpool, Liverpool, United Kingdom
| | - Savita Madhusudhan
- St Paul's Eye Unit, Liverpool University Hospitals NHS Foundation Trust, Liverpool, United Kingdom
- Department of Eye and Vision Sciences, Institute of Life Course and Medical Sciences, University of Liverpool, Liverpool, United Kingdom
| | - Yalin Zheng
- St Paul's Eye Unit, Liverpool University Hospitals NHS Foundation Trust, Liverpool, United Kingdom
- Department of Eye and Vision Sciences, Institute of Life Course and Medical Sciences, University of Liverpool, Liverpool, United Kingdom
| | - Wahbi K. El-Bouri
- Liverpool Centre for Cardiovascular Science, University of Liverpool and Liverpool Heart and Chest Hospital, Liverpool, United Kingdom
- Department of Cardiovascular and Metabolic Medicine, Institute of Life Course and Medical Sciences, University of Liverpool, Liverpool, United Kingdom
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Han HJ, Kim JM. The Relationship between Transcranial Doppler Ultrasonography and Visual Field Test Results in Glaucoma and Glaucoma Suspect Patients. KOREAN JOURNAL OF OPHTHALMOLOGY 2023; 37:437-445. [PMID: 37899287 PMCID: PMC10721401 DOI: 10.3341/kjo.2023.0052] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2023] [Revised: 08/28/2023] [Accepted: 09/06/2023] [Indexed: 10/31/2023] Open
Abstract
PURPOSE To evaluate the relationships between parameters of transcranial ultrasonography and results of visual field tests in patients with open angle glaucoma or suspected of having glaucoma. METHODS This retrospective study was based on data from medical records of patients who visited the Department of Ophthalmology in Kangbuk Samsung Hospital from January 1, 2016, to October 17, 2019, and underwent transcranial Doppler ultrasonography as part of a routine health examination. Ophthalmic data were visual acuity, intraocular pressure, optical coherence tomography, and Humphrey visual field test results. Retinal nerve fiber layer defect was confirmed by a glaucoma specialist. Patients' ophthalmic data, such as average ganglion cell layer thickness, visual field index, pattern standard deviation, and mean deviation, were divided into quartiles. Each ophthalmic artery parameter from transcranial Doppler ultrasonography was compared between quartiles. RESULTS A total of 162 patients were reviewed. There was no difference in Doppler ophthalmic artery (OA) parameters between patients with or without retinal nerve fiber layer defect. None of the quartile groups of average ganglion cell layer thickness showed significant difference in any OA parameters. Patients in the low-visual field index quartile showed significant low peak systolic velocities of OAs when adjusted for age, sex, and presence of diabetes mellitus or hypertension (p = 0.016). A higher pattern standard deviation showed lower peak systolic velocity (p = 0.046). There was no significant tendency between any other OA parameter and mean deviation value. CONCLUSIONS Our study suggests that hemodynamic parameters of ophthalmic arteries might be associated with visual field status of patients. Further large-population studies are needed in order to better understand the relationship between visual function and ocular blood flow.
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Affiliation(s)
- Hyo Ji Han
- Department of Ophthalmology, Kangbuk Samsung Hospital, Sungkyunkwan University School of Medicine, Seoul, Korea
| | - Joon Mo Kim
- Department of Ophthalmology, Kangbuk Samsung Hospital, Sungkyunkwan University School of Medicine, Seoul, Korea
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Kolli A, Toris CB, Reed DM, Gilbert J, Sit AJ, Gulati V, Kazemi A, Fan S, Musch DC, Moroi SE. The Effects of Topical Timolol and Latanoprost on Calculated Ocular Perfusion Pressure in Nonglaucomatous Volunteers. J Ocul Pharmacol Ther 2021; 37:565-574. [PMID: 34610254 PMCID: PMC8713568 DOI: 10.1089/jop.2021.0068] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2021] [Accepted: 08/26/2021] [Indexed: 11/13/2022] Open
Abstract
Purpose: To characterize the effects of timolol and latanoprost on calculated ocular perfusion pressure (OPP) in a multicenter, prospective, crossover-design study. Methods: Nonglaucomatous volunteers were evaluated at baseline, after 1 week of timolol 0.5% dosed twice daily, and after 1 week of latanoprost 0.005% dosed nightly (randomized treatment order; 6-week washout period). Pneumatonometric intraocular pressure (IOP) and brachial blood pressure (BP) were evaluated at each visit. Using 3 commonly used equations, OPP was calculated based on IOP and BP. The OPPs at each visit were compared by using linear mixed-effects models. Results: This analysis includes 121 participants (242 eyes; 75% female, 87% White, mean age 55 years). Mean OPP (standard deviation) calculated with mean arterial pressure was 46.8 (8.1) mmHg at baseline, 48.5 (7.9) mmHg with timolol (P = 0.005), and 49.6 mmHg (8.2) with latanoprost (P < 0.001). When compared with baseline, OPP calculated with diastolic BP was significantly increased with both timolol (1.3 mmHg) and latanoprost (3.1 mmHg). The OPP calculated with systolic BP was increased with latanoprost (2.8 mmHg) but decreased with timolol (-1.3 mmHg). Timolol reduced systolic BP by 3.2 mmHg. Compared with timolol, latanoprost conferred greater increases in OPP calculated with both systolic and diastolic BP compared with baseline; however, the difference in treatment effects on OPP calculated with mean arterial pressure was not significantly different (P = 0.068). Conclusion: In this crossover study of nonglaucomatous volunteers, latanoprost increased OPP. However, timolol's benefit to OPP may be limited in part because it reduced systolic BP. Clinical Trial Registration number: NCT01677507.
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Affiliation(s)
- Ajay Kolli
- Department of Ophthalmology and Visual Sciences, Kellogg Eye Center, University of Michigan, Ann Arbor, Michigan, USA
| | - Carol B. Toris
- Department of Ophthalmology and Visual Sciences, University of Nebraska Medical Center, Omaha, Nebraska, USA
- Department of Ophthalmology and Visual Sciences, The Ohio State University Wexner Medical Center, Columbus, Ohio, USA
| | - David M. Reed
- Department of Ophthalmology and Visual Sciences, The Ohio State University Wexner Medical Center, Columbus, Ohio, USA
| | - Jesse Gilbert
- Department of Ophthalmology and Visual Sciences, The Ohio State University Wexner Medical Center, Columbus, Ohio, USA
| | - Arthur J. Sit
- Department of Ophthalmology, Mayo Clinic, Rochester, Minnesota, USA
| | - Vikas Gulati
- Department of Ophthalmology and Visual Sciences, University of Nebraska Medical Center, Omaha, Nebraska, USA
| | - Arash Kazemi
- Department of Ophthalmology, Mayo Clinic, Rochester, Minnesota, USA
| | - Shan Fan
- Department of Ophthalmology and Visual Sciences, University of Nebraska Medical Center, Omaha, Nebraska, USA
| | - David C. Musch
- Department of Ophthalmology and Visual Sciences, Kellogg Eye Center, University of Michigan, Ann Arbor, Michigan, USA
- Department of Epidemiology, School of Public Health, University of Michigan, Ann Arbor, Michigan, USA
| | - Sayoko E. Moroi
- Department of Ophthalmology and Visual Sciences, Kellogg Eye Center, University of Michigan, Ann Arbor, Michigan, USA
- Department of Ophthalmology and Visual Sciences, The Ohio State University Wexner Medical Center, Columbus, Ohio, USA
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Comparison of Medical Comorbidity between Patients with Normal-Tension Glaucoma and Primary Open-Angle Glaucoma: A Population-Based Study in Taiwan. Healthcare (Basel) 2021; 9:healthcare9111509. [PMID: 34828558 PMCID: PMC8624536 DOI: 10.3390/healthcare9111509] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2021] [Revised: 10/27/2021] [Accepted: 11/01/2021] [Indexed: 11/17/2022] Open
Abstract
The objective was to investigate different comorbidities developed in normal-tension glaucoma (NTG) and primary open-angle glaucoma (POAG) patients. This was a case-control study, with 1489 people in the NTG group and 5120 people in the POAG group. Patient data were obtained from the Longitudinal Health Insurance Database 2010 (LHID2010) of Taiwan for the 2008-2013 period. The chi-square test was used to compare categorical variables, such as gender, income and urbanisation level, between NTG and POAG patients, and the two-tailed t test was used to compare continuity between the two groups. We use a multivariate logic regression model to assess the risk of each participant. The results are expressed in terms of odds ratio (OR) and 95% confidence intervals (CI). Patients with NTG had significantly higher proportions of hypotension (adjusted OR, 1.984; 95% CI, 1.128-3.490), sleep disturbances (adjusted OR, 1.323; 95% CI, 1.146-1.528), peptic ulcers (adjusted OR, 1.383; 95% CI, 1.188-1.609) and allergic rhinitis (adjusted OR, 1.484; 95% CI, 1.290-1.707) than those with POAG. Conversely, arterial hypertension (adjusted OR, 0.767; 95% CI, 0.660-0.893), diabetes (adjusted OR, 0.850; 95% CI, 0.728-0.993) and atopic dermatitis (adjusted OR, 0.869; 95% CI, 0.763-0.990) had a lower risk in the NTG group than in the POAG group. We found that comorbidities such a hypotension, sleep disturbances and peptic ulcer and allergic rhinitis are more highly associated to NTG than POAG.
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Kristiansen M, Lindén C, Qvarlander S, Wåhlin A, Ambarki K, Hallberg P, Eklund A, Jóhannesson G. Feasibility of MRI to assess differences in ophthalmic artery blood flow rate in normal tension glaucoma and healthy controls. Acta Ophthalmol 2021; 99:e679-e685. [PMID: 33210819 PMCID: PMC8451810 DOI: 10.1111/aos.14673] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2020] [Revised: 10/05/2020] [Accepted: 10/14/2020] [Indexed: 11/30/2022]
Abstract
Purpose To examine feasibility of phase‐contrast magnetic resonance imaging (PCMRI) and to assess blood flow rate in the ophthalmic artery (OA) in patients with normal tension glaucoma (NTG) compared with healthy controls. Methods Sixteen patients with treated NTG and 16 age‐ and sex‐matched healthy controls underwent PCMRI using a 3‐Tesla scanner and ophthalmological examinations. OA blood flow rate was measured using a 2D PCMRI sequence with a spatial resolution of 0.35 mm2. Results The blood flow rate in the NTG group was 9.6 ± 3.9 ml/min [mean ± SD] compared with 11.9 ± 4.8 ml/min in the control group. Resistance Index (RI) and Pulsatility Index (PI) were 0.73 ± 0.08 and 1.36 ± 0.29, respectively, in the NTG group and 0.68 ± 0.13 and 1.22 ± 0.40, respectively, in the healthy group. The mean visual field index (VFI) was 46% ± 25 for the worse NTG eyes. The measured differences observed between the NTG group and the control group in blood flow rate (p = 0.12), RI (p = 0.18) and PI (p = 0.27) were non‐significant. Conclusions This case–control study, using PCMRI, showed a slight, but non‐significant, reduction in OA blood flow rate in the NTG patients compared with the healthy controls. These results indicate that blood flow may be of importance in the pathogenesis of NTG. Considering that only a limited portion of the total OA blood flow supplies the ocular system and the large inter‐individual differences, a larger study or more advanced PCMRI technique might give the answer.
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Affiliation(s)
- Martin Kristiansen
- Department of Clinical Sciences Ophthalmology Umeå University Umeå Sweden
| | - Christina Lindén
- Department of Clinical Sciences Ophthalmology Umeå University Umeå Sweden
| | - Sara Qvarlander
- Department of Radiation Sciences Biomedical Engineering Umeå University Umeå Sweden
- Centre for Biomedical Engineering and Physics Umeå University Umeå Sweden
| | - Anders Wåhlin
- Department of Radiation Sciences Biomedical Engineering Umeå University Umeå Sweden
- Centre for Biomedical Engineering and Physics Umeå University Umeå Sweden
- Umeå Center for Functional Brain Imaging Umeå University Umeå Sweden
| | - Khalid Ambarki
- Department of Radiation Sciences Biomedical Engineering Umeå University Umeå Sweden
- Centre for Biomedical Engineering and Physics Umeå University Umeå Sweden
| | - Per Hallberg
- Centre for Biomedical Engineering and Physics Umeå University Umeå Sweden
- Dept. of Applied Physics and Electronics Umeå University Umeå Sweden
| | - Anders Eklund
- Department of Radiation Sciences Biomedical Engineering Umeå University Umeå Sweden
- Centre for Biomedical Engineering and Physics Umeå University Umeå Sweden
| | - Gauti Jóhannesson
- Department of Clinical Sciences Ophthalmology Umeå University Umeå Sweden
- Wallenberg Center for Molecular Medicine Umeå University Umeå Sweden
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Abstract
Glaucoma is a chronic progressive optic neuropathy that causes irreversible loss of visual functions. From the clinical point of view, normal-tension glaucoma (NTG) is regarded in Russian taxonomy as a clinical form of standard primary open-angle glaucoma in which the IOP values stay within the normal range, but the typical progressive visual functions loss is still present. The results of the latest studies put in question the traditional views of NTG pathophysiology that are based solely on intraocular pressure values. New capabilities of diagnostic visualization of central nervous system have considerably broadened our knowledge of the NTG development mechanisms. This article reviews current understanding of the pathogenesis of NTG and its connection to vascular and immune factors, translaminar pressure difference etc. The review also considers the relationship between glaucoma and cognitive defects associated with Alzheimer's and Parkinson's diseases.
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Affiliation(s)
- S Yu Petrov
- Research Institute of Eye Diseases, Moscow, Russia
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7
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Ocular Perfusion Pressure and the Risk of Open-Angle Glaucoma: Systematic Review and Meta-analysis. Sci Rep 2020; 10:10056. [PMID: 32572072 PMCID: PMC7308312 DOI: 10.1038/s41598-020-66914-w] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2019] [Accepted: 05/28/2020] [Indexed: 02/03/2023] Open
Abstract
Low ocular perfusion pressure (OPP) has been proposed as an important risk factor for glaucoma development and progression, but controversy still exists between studies. Therefore, we conducted a systematic review and meta-analysis to analyze the association between OPP and open-angle glaucoma (OAG). Studies were identified by searching PubMed and EMBASE databases. The pooled absolute and standardised mean difference in OPP between OAG patients and controls were evaluated using the random-effects model. Meta-regression analysis was conducted to investigate the factors associated with OPP difference between OAG patients and controls. A total of 43 studies were identified including 3,009 OAG patients, 369 patients with ocular hypertension, and 29,502 controls. The pooled absolute mean difference in OPP between OAG patients and controls was −2.52 mmHg (95% CI −4.06 to −0.98), meaning significantly lower OPP in OAG patients (P = 0.001). Subgroup analyses showed that OAG patients with baseline IOP > 21 mmHg (P = 0.019) and ocular hypertension patients also had significantly lower OPP than controls (P < 0.001), but such difference in OPP was not significant between OAG patients with baseline IOP of ≤21 mmHg and controls (P = 0.996). In conclusion, although no causal relationship was proven in the present study, our findings suggest that in patients with high baseline IOP, who already have a higher risk of glaucoma, low OPP might be another risk factor.
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8
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Gardiner SK, Cull G, Fortune B, Wang L. Increased Optic Nerve Head Capillary Blood Flow in Early Primary Open-Angle Glaucoma. Invest Ophthalmol Vis Sci 2019; 60:3110-3118. [PMID: 31323681 PMCID: PMC6645706 DOI: 10.1167/iovs.19-27389] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Abstract
Purpose Blood flow in the optic nerve head (ONH) is known to be reduced in eyes with advanced glaucoma. However, experimental results from non-human primates suggest an initial increase in ONH blood flow at the earliest stages of damage. This study assesses flow and pulsatile hemodynamics across a range of severities to test the hypothesis that this also occurs in human glaucoma. Methods Laser speckle flowgraphy was used to measure average mean blur rate (MBRave) within ONH tissue (a correlate of capillary blood flow) and the pulsatile waveform in 93 eyes with functional loss and 74 glaucoma suspect/fellow eyes without functional loss. These were compared against results from 92 healthy control eyes. Parameters produced by the instrument's software were age-corrected, then compared between groups using generalized estimating equation models. Results The mean MBRave in the control eyes was 12.5 units. In glaucoma suspect/fellow eyes, the mean was 16.4 units, higher with P < 0.0001. In eyes with functional loss, the mean was 13.8 units, lower than eyes without functional loss with P < 0.0001, although still higher than control eyes with P = 0.0096. Analysis of the pulsatile waveform suggested that the deceleration in flow as it approaches its maximum across the cardiac cycle was delayed in glaucoma. Conclusions Blood flow within ONH capillaries was higher in glaucoma suspect eyes than in healthy controls. It was less elevated in eyes that had developed functional loss. The mechanisms causing these changes and their relation to concurrent changes in pulsatile hemodynamics remain under investigation.
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Affiliation(s)
- Stuart K Gardiner
- Devers Eye Institute, Legacy Health, Portland, Oregon, United States
| | - Grant Cull
- Devers Eye Institute, Legacy Health, Portland, Oregon, United States
| | - Brad Fortune
- Devers Eye Institute, Legacy Health, Portland, Oregon, United States
| | - Lin Wang
- Devers Eye Institute, Legacy Health, Portland, Oregon, United States
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9
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Onishi AC, Treister AD, Nesper PL, Fawzi AA, Anchala AR. Parafoveal vessel changes in primary open-angle glaucoma and normal-tension glaucoma using optical coherence tomography angiography. Clin Ophthalmol 2019; 13:1935-1945. [PMID: 31579266 PMCID: PMC6773972 DOI: 10.2147/opth.s206288] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2019] [Accepted: 06/17/2019] [Indexed: 11/25/2022] Open
Abstract
Purpose To evaluate parafoveal and peripapillary perfusion in healthy, glaucoma suspect, normal-tension glaucoma, and primary open-angle glaucoma subjects. Patients and methods This was a retrospective cross-sectional study with optical coherence tomography angiography imaging with RTVue XR Avanti (Optovue, Inc., Fremont, CA) of 56 eyes (14 healthy, 14 glaucoma suspect, 16 normal-tension glaucoma, and 12 primary open-angle glaucoma) at a tertiary academic referral center. Parafoveal and peripapillary superficial vessel density and parafoveal superficial retinal thickness were the main parameters of interest. Area under receiver operating characteristic curves were calculated. Results There were significant decreases in parafoveal superficial vessel density in primary open-angle (40.06±4.54%, P<0.001) and normal-tension glaucoma (42.82±5.16%, P=0.010) but not suspect eyes (45.72±4.37%, P=0.916) compared to healthy eyes (48.10±2.82%). Similarly, decreases were observed in parafoveal inner retinal thickness in primary open-angle (83.19±14.29 μm, P<0.001) and normal-tension glaucoma eyes (94.97±12.44 μm, P=0.035), but not suspect eyes (99.93±9.00 μm, P=0.648), compared to healthy controls (107.00±9.55 μm). Only primary open-angle glaucoma eyes displayed significant changes in peripapillary vessel density (37.63±7.19%) compared to healthy controls (49.12±2.80%, P<0.001). Further statistical adjustment for sex and age revealed a significant decrease in parafoveal vessel density in suspects relative to controls (P=0.039). Diagnostic accuracy of parafoveal vessel density was high with an area under the curve of 0.833±0.073 for normal-tension glaucoma and 0.946±0.049 for primary open-angle glaucoma. Conclusion Parafoveal vessel density was significantly reduced in glaucomatous eyes, with good diagnostic accuracy. These findings provide further evidence that these changes may be useful in the diagnosis and monitoring of disease in glaucoma patients.
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Affiliation(s)
- Alex C Onishi
- Department of Ophthalmology, Feinberg School of Medicine, Northwestern University, Chicago, IL, USA
| | - Alison D Treister
- Department of Ophthalmology, Feinberg School of Medicine, Northwestern University, Chicago, IL, USA
| | - Peter L Nesper
- Department of Ophthalmology, Feinberg School of Medicine, Northwestern University, Chicago, IL, USA
| | - Amani A Fawzi
- Department of Ophthalmology, Feinberg School of Medicine, Northwestern University, Chicago, IL, USA
| | - Anupama R Anchala
- Department of Ophthalmology, Feinberg School of Medicine, Northwestern University, Chicago, IL, USA
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10
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Abstract
Glaucoma is a chronic, progressive optic neuropathy characterized by the loss of peripheral vision first and then central vision. Clinically, normal tension glaucoma is considered a special subtype of glaucoma, in which the patient's intraocular pressure is within the normal range, but the patient experiences typical glaucomatous changes. However, increasing evidence has challenged the traditional pathophysiological view of normal tension glaucoma, which is based only on intraocular pressure, and breakthroughs in central nervous system imaging may now greatly increase our knowledge about the mechanisms underlying normal tension glaucoma. In this article, we review the latest progress in understanding the pathogenesis of normal tension glaucoma and in developing imaging techniques to detect it, to strengthen the appreciation for the connection between normal tension glaucoma and the brain.
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Affiliation(s)
- Hui-Jun Zhang
- Department of Ophthalmology, the First Affiliated Hospital of Jinan University, Guangzhou, Guangdong Province, China
| | - Xue-Song Mi
- Department of Ophthalmology, the First Affiliated Hospital of Jinan University, Guangzhou, Guangdong Province, China
| | - Kwok-Fai So
- Guangdong-Hong Kong-Macau Institute of CNS Regeneration, Jinan University, Guangzhou, Guangdong Province; State Key Laboratory of Brain and Cognitive Sciences; Department of Ophthalmology, The University of Hong Kong, Pokfulam, Hong Kong Special Administrative Region, China
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11
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Zhang S, Wu C, Liu L, Jia Y, Zhang Y, Zhang Y, Zhang H, Zhong Y, Huang D. Optical Coherence Tomography Angiography of the Peripapillary Retina in Primary Angle-Closure Glaucoma. Am J Ophthalmol 2017; 182:194-200. [PMID: 28797550 DOI: 10.1016/j.ajo.2017.07.024] [Citation(s) in RCA: 42] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2017] [Revised: 07/30/2017] [Accepted: 07/31/2017] [Indexed: 01/26/2023]
Abstract
PURPOSE To measure the change of peripapillary retinal vessel density (VD) in eyes with a history of acute primary angle-closure glaucoma (PACG). DESIGN Case-control study. METHODS Twenty-one consecutive Chinese patients with history of unilateral acute PACG were enrolled. Eyes with acute PACG constituted the case group, while the contralateral eyes without attack constituted the control. All patients underwent ophthalmic examinations including best-corrected visual acuity, intraocular pressure, and visual field (VF). Spectral-domain optical coherence tomography (SD-OCT) was used to obtain both structural OCT and OCT angiography (OCTA). Structural OCT scans provided thickness measurements of the peripapillary retinal nerve fiber layer (RNFL) and macular ganglion cell complex (GCC). OCTA was used to measure all-plexus peripapillary retinal VD. RESULTS In unaffected eyes, a dense microvascular network surrounded the disc on all-plexus retinal OCTA. The vascular network was visibly attenuated and focal capillary dropout was evident in acute PACG eyes. The peripapillary VD in acute PACG eyes was 66.6% ± 17.3% (mean ± standard deviation), which was significantly (P < .01) reduced compared to 87.2% ± 8.6% in the unaffected eyes. In acute PACG eyes, peripapillary retinal VD was positively correlated with RNFL and GCC thicknesses (P < .001 each) and negatively correlated with VF mean deviation (P = .002) and cup-to-disc ratio (P = .0064). In unaffected eyes, there were no correlations between peripapillary retinal VD and glaucoma-related parameters. CONCLUSIONS In acute PACG eyes, peripapillary retinal VD decreased significantly compared with the contralateral unaffected eyes. Peripapillary retinal VD was significantly correlated with other glaucomatous changes.
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12
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Magureanu M, Stanila A, Bunescu LV, Armeanu C. Color Doppler imaging of the retrobulbar circulation in progressive glaucoma optic neuropathy. Rom J Ophthalmol 2016; 60:237-248. [PMID: 29450356 PMCID: PMC5711288] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 09/15/2016] [Indexed: 06/08/2023] Open
Abstract
It is known that elevated intraocular pressure (IOP) is the primary risk factor for glaucoma. Recently, more and more evidences have shown that the vascular deficit also plays an important role in the pathogenesis and progressions of glaucomatous optic neuropathy. This issue is backed up by glaucomatous optic neuropathy (GON) cases drug compensated in which the progression of the disease in one or both eyes is ascertained despite a normal and relatively constant IOP. The present study evaluated the hemodynamic parameters in the retrobulbar circulation in patients with progressive glaucomatous optic neuropathy in one eye, who received compensated medication. The hemodynamic parameters (PSV, EDV, IR) were measured by using color Doppler ultrasound and progression was evaluated by a repeated automated perimetry. The obtained values were statistically analyzed and compared with those obtained for the stable eye.
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Affiliation(s)
| | - Adriana Stanila
- Research Center of Ocular Surface, “Lucian Blaga” University,
Ophthalmology Clinic - RCOS, Sibiu, Romania
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13
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Magureanu M, Stanila A, Bunescu LV, Armeanu C. Survey on retrobulbar blood flow in glaucomatous optic neuropathy (normotensive and hypertensive). Rom J Ophthalmol 2016; 60:231-236. [PMID: 29450355 PMCID: PMC5711287] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 09/18/2016] [Indexed: 06/08/2023] Open
Abstract
The aim of this study was to analyze the possible differences between retrobulbar blood flows in normotensive glaucomatous optic neuropathy patients versus patients with hypertensive glaucomatous optic neuropathy, with intraocular pressure controlled treatment. All the patients in the study group were subjected to a color Doppler echography of retrobulbar vessels. Afterwards, systolic and diastolic blood velocities were measured in both eyes in ophthalmic artery (OA), central retinal artery (CRA) and posterior ciliary arteries (PCA). The device calculated the Resistivity index Pourcelot (RI) automatically.
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Affiliation(s)
| | - Adriana Stanila
- Research Center of Ocular Surface, Ophthalmology Clinic - RCOS,
Ophthalmology Department, “Lucian Blaga” University of
Medicine and Pharmacy, Sibiu, Romania
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14
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Mohindroo C, Ichhpujani P, Kumar S. Current Imaging Modalities for assessing Ocular Blood Flow in Glaucoma. J Curr Glaucoma Pract 2016; 10:104-112. [PMID: 27857490 PMCID: PMC5104970 DOI: 10.5005/jp-journals-10008-1210] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2016] [Accepted: 06/12/2016] [Indexed: 11/29/2022] Open
Abstract
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 of ocular blood flow. This review article attempts to provide detailed information on ocular perfu-sion pressure as well as an overview of the newly developed imaging technologies used to investigate ocular blood flow in glaucoma patients. HOW TO CITE THIS ARTICLE Mohindroo C, Ichhpujani P, Kumar S. Current Imaging Modalities for assessing Ocular Blood Flow in Glaucoma. J Curr Glaucoma Pract 2016;10(3):104-112.
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Affiliation(s)
- Chirayu Mohindroo
- Intern, Department of Ophthalmology, Government Medical College and Hospital, Chandigarh, India
| | - Parul Ichhpujani
- Associate Professor, Department of Ophthalmology, Government Medical College and Hospital, Chandigarh, India
| | - Suresh Kumar
- Professor, Department of Ophthalmology, Government Medical College and Hospital, Chandigarh, India
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