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Shajiei TD, Iadanza S, Bachmann LM, Kniestedt C. Inventory of Ocular Pulse Amplitude Values in Healthy Subjects and Patients With Ophthalmologic Illnesses: Systematic Review and Meta-analysis. Am J Ophthalmol 2024; 259:151-165. [PMID: 37898282 DOI: 10.1016/j.ajo.2023.10.014] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2023] [Revised: 10/18/2023] [Accepted: 10/20/2023] [Indexed: 10/30/2023]
Abstract
PURPOSE Many studies have examined the ocular pulse amplitude (OPA) to better understand its physiology and clinical relevance, but the papers are scattered, not consistently indexed, and sometimes difficult to locate. We aimed to identify and summarize the relevant published evidence on OPA and, in a meta-analysis, outline specific differences of this parameter between healthy individual, primary open-angle glaucoma, normal-tension glaucoma, ocular hypertension, and cataract patients. DESIGN Systematic review and meta-analysis. METHODS A thorough literature search and data extraction were conducted by 2 reviewers independently. Reports on OPA measured by the dynamic contour tonometry in conjunction with different ocular and systemic diseases or potential influencing factors were included. RESULTS Of the 527 initially found reports, 97 met the inclusion criteria assessing 31 clinical conditions. A meta-analysis based on 6850 eyes and 106 study arms (68.8%) revealed differences in mean OPA values in millimeters of mercury between various entities. Among healthy eyes, the OPA was 2.58 mm Hg (95% CI: 2.45-2.71), whereas OPA values were higher in glaucoma (unspecified glaucoma 2.73 mm Hg, 95% CI: 2.38-3.08; normal-tension glaucoma 2.66 mm Hg, 95% CI: 2.36-2.97; and primary open-angle glaucoma 2.92 mm Hg, 95% CI: 2.75-3.08). Although ocular hypertension showed the highest OPA values (3.53 mm Hg, 95% CI: 3.05-4.01), the lowest values were found in cataract eyes (2.26 mm Hg, 95% CI: 1.57-2.94). CONCLUSION We found different OPA values characteristic of different clinical entities, with above-normal values in glaucoma and ocular hypertension and lower values in cataract patients. Our work is intended for clinicians and researchers who want to get a quick overview of the available evidence or who need statistical data on OPA distributions in individual diseases.
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Affiliation(s)
- Tania D Shajiei
- From the Talacker Augen Zentrum Zürich (TAZZ), Department of Ophthalmology, University Hospital Zurich (T.D.S.), Zurich, Switzerland
| | - Sandro Iadanza
- Talacker Augen Zentrum Zürich (S.I., C.K.), Zurich, Switzerland
| | - Lucas M Bachmann
- Medignition Inc, Research Consultants (L.M.B.), Zurich, Switzerland.
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Bora RR, Prasad R, Mathurkar S, Bhojwani K, Prasad A. Cardiovascular Manifestations of Pseudoexfoliation Syndrome: A Narrative Review. Cureus 2024; 16:e51492. [PMID: 38304644 PMCID: PMC10831210 DOI: 10.7759/cureus.51492] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2023] [Accepted: 01/01/2024] [Indexed: 02/03/2024] Open
Abstract
Pseudoexfoliation syndrome (PEX) is a long-term, age-related extracellular matrix condition that causes aberrant fibrillary pseudoexfoliative material (PXM) to accumulate in various body tissues. The anterior portion of the eye is where this disorder most frequently presents. It affects the entire body. Most frequently, it is seen in older people, usually those over 50. Fibrillar deposits are a symptom of the pseudoexfoliation syndrome and are found in the anterior part of the eye. Deposition of fibrillary white flaky material is seen. The lens capsule, cornea, ciliary epithelium, lens epithelium, iris pigment epithelium, zonules, orbital soft tissues, trabecular meshwork, iris blood vessels, and iris stroma have all been reported to show such depositions. The skin, heart, lungs, liver, kidneys, and other organs have also been reported to contain these deposits. Asymmetrical and bilateral illnesses are both possible. Myocardial infarction, cerebrovascular accidents, and systemic hypertension have all been linked to it. The pseudoexfoliative condition was first reported with the characteristic findings of white or grey flakes on the anterior lens capsule, the prevalence of glaucoma rising with age, and its presence in about 50% of eyes. A few decades later, the term pseudoexfoliation was given to differentiate it from the true exfoliation syndrome. True exfoliation syndrome is characterized by lamellar delamination of the lens capsule and is caused by exposure to infrared radiation. It is commonly seen in glassblowers. Age is a risk factor for PEX once a person reaches 70. Symptoms of PEX include elevated intraocular pressure, peripapillary transillumination deficiencies, potential glaucomatous optic nerve damage, poor dilatation, Sampaolesi line, and fibrillar white flaky deposits along the pupillary border. Meanwhile, fibrillar white flaky deposits on the anterior lens capsule (Hoarfrost Ring) and pigment dispersion syndrome are not pathognomonic.
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Affiliation(s)
- Rajal R Bora
- Medicine, Jawaharlal Nehru Medical College, Datta Meghe Institute of Higher Education and Research, Wardha, IND
| | - Roshan Prasad
- Medicine, Jawaharlal Nehru Medical College, Datta Meghe Institute of Higher Education and Research, Wardha, IND
| | - Swapneel Mathurkar
- Ophthalmology, Jawaharlal Nehru Medical College, Datta Meghe Institute of Higher Education and Research, Wardha, IND
| | - Kashish Bhojwani
- Pathology, Jawaharlal Nehru Medical College, Datta Meghe Institute of Higher Education and Research, Wardha, IND
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Raphtis VA, Sharma D, Wang S, Kim JY, Jacobson AL, Harman CD, Komáromy AM. Ocular pulse amplitude (OPA) in canine ADAMTS10-open-angle glaucoma ( ADAMTS10-OAG). Front Bioeng Biotechnol 2023; 11:1242166. [PMID: 38130820 PMCID: PMC10733518 DOI: 10.3389/fbioe.2023.1242166] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2023] [Accepted: 11/27/2023] [Indexed: 12/23/2023] Open
Abstract
Introduction: The role of ocular rigidity and biomechanics remains incompletely understood in glaucoma, including assessing an individual's sensitivity to intraocular pressure (IOP). In this regard, the clinical assessment of ocular biomechanics represents an important need. The purpose of this study was to determine a possible relationship between the G661R missense mutation in the ADAMTS10 gene and the ocular pulse amplitude (OPA), the difference between diastolic and systolic intraocular pressure (IOP), in a well-established canine model of open-angle glaucoma (OAG). Methods: Animals studied included 39 ADAMTS10-mutant dogs with different stages of OAG and 14 unaffected control male and female dogs between 6 months and 12 years (median: 3.2 years). Dogs were sedated intravenously with butorphanol tartrate and midazolam HCl, and their IOPs were measured with the Icare® Tonovet rebound tonometer. The Reichert Model 30™ Pneumotonometer was used to measure OPA. Central corneal thickness (CCT) was measured via Accutome® PachPen, and A-scan biometry was assessed with DGH Technology Scanmate. All outcome measures of left and right eyes were averaged for each dog. Data analysis was conducted with ANOVA, ANCOVA, and regression models. Results: ADAMTS10-OAG-affected dogs displayed a greater IOP of 23.0 ± 7.0 mmHg (mean ± SD) compared to 15.3 ± 3.6 mmHg in normal dogs (p < 0.0001). Mutant dogs had a significantly lower OPA of 4.1 ± 2.0 mmHg compared to 6.5 ± 2.8 mmHg of normal dogs (p < 0.01). There was no significant age effect, but OPA was correlated with IOP in ADAMTS10-mutant dogs. Conclusion: The lower OPA in ADAMTS10-mutant dogs corresponds to the previously documented weaker and biochemically distinct posterior sclera, but a direct relationship remains to be confirmed. The OPA may be a valuable clinical tool to assess ocular stiffness and an individual's susceptibility to IOP elevation.
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Affiliation(s)
- Vanessa A. Raphtis
- Department of Small Animal Clinical Sciences, College of Veterinary Medicine, Michigan State University, East Lansing, MI, United States
| | - Dhruv Sharma
- Center for Statistical Training and Consulting, Michigan State University, East Lansing, MI, United States
| | - Sichao Wang
- Center for Statistical Training and Consulting, Michigan State University, East Lansing, MI, United States
| | - Jae Y. Kim
- Department of Small Animal Clinical Sciences, College of Veterinary Medicine, Michigan State University, East Lansing, MI, United States
| | - Amanda L. Jacobson
- Department of Small Animal Clinical Sciences, College of Veterinary Medicine, Michigan State University, East Lansing, MI, United States
| | - Christine D. Harman
- Department of Small Animal Clinical Sciences, College of Veterinary Medicine, Michigan State University, East Lansing, MI, United States
| | - András M. Komáromy
- Department of Small Animal Clinical Sciences, College of Veterinary Medicine, Michigan State University, East Lansing, MI, United States
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Jordanova E, Hentova-Sencanic P, Marjanović I, Senčanin I, Stefanović I, Baralić M. The cornea and methods for measuring intraocular pressure. SANAMED 2022. [DOI: 10.5937/sanamed0-41040] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023] Open
Abstract
Introduction: The study aimed to assert the relationship between central corneal thickness (CCT) and intraocular pressure (IOP) measured by: Goldmann applanation tonometry (GAT) and Dynamic contour tonometry (DCT). Materials and Methods: The study included 150 patients with a mean age of 59.39 ± 13.12 years. Patients were divided into three groups: 50 primary open-angle glaucoma (POAG) patients, 50 ocular hypertension (OHT) patients, and 50 normal tension glaucoma (NTG) patients. IOP was determined using GAT and DCT. CCT was measured by ultrasound pachymetry. Results: IOP measured with DCT was higher than IOP measured with GAT (19.80 ± 3.67 mmHg vs 17.71 ± 3.35 mmHg). A significant positive association between IOP measured with GAT and IOP measured with DCT was found in all patients (r = 0.867, p < 0.01). A significantly positive association between IOP measured with GAT and IOP measured with DCT in POAG (r = 0.855, p <0.01), OHT (r = 0.826, p < 0.01), and NTG patients (r = 0.832, p < 0.01) were found. A significant positive correlation between CCT and IOP measured with GAT (r = 0.198, p < 0.01), as well as a significant positive correlation between CCT and IOP measured with DCT was found (r = 0.198, p < 0.01) in all patients. There was no correlation between CCT and IOP measured neither with GAT nor with DCT separately in three patient groups (p > 0.05). Conclusion: CCT-influenced IOP was measured by both methods, GAT and DCT. DCT can not replace GAT, but it is very useful, especially in cases where errors are in the IOP GAT measurement.
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Jin Y, Wang X, Zhang L, Jonas JB, Aung T, Schmetterer L, Girard MJA. Modeling the Origin of the Ocular Pulse and Its Impact on the Optic Nerve Head. ACTA ACUST UNITED AC 2018; 59:3997-4010. [DOI: 10.1167/iovs.17-23454] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Affiliation(s)
- Yuejiao Jin
- NUS Graduate School for Integrative Sciences and Engineering, National University of Singapore, Singapore
- Department of Biomedical Engineering, National University of Singapore, Singapore
| | - Xiaofei Wang
- Department of Biomedical Engineering, National University of Singapore, Singapore
| | - Liang Zhang
- NUS Graduate School for Integrative Sciences and Engineering, National University of Singapore, Singapore
- Department of Biomedical Engineering, National University of Singapore, Singapore
| | - Jost B. Jonas
- Department of Ophthalmology of the Medical Faculty Mannheim of the Ruprecht-Karls-University Heidelberg, Heidelberg, Germany
| | - Tin Aung
- Singapore Eye Research Institute, Singapore National Eye Centre, Singapore
- Duke-NUS Medical School, Singapore
- Department of Ophthalmology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore
| | - Leopold Schmetterer
- Singapore Eye Research Institute, Singapore National Eye Centre, Singapore
- Duke-NUS Medical School, Singapore
- Lee Kong Chian School of Medicine, Nanyang Technological University, Singapore
- Department of Clinical Pharmacology, Medical University of Vienna, Vienna, Austria
- Center for Medical Physics and Biomedical Engineering, Medical University of Vienna, Vienna, Austria
| | - Michaël J. A. Girard
- Department of Biomedical Engineering, National University of Singapore, Singapore
- Singapore Eye Research Institute, Singapore National Eye Centre, Singapore
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Affiliation(s)
- Timothy E. Yap
- Imperial College Healthcare NHS Trust (ICHNT), The Western Eye Hospital, London, UK
- The Imperial College Ophthalmic Research Group (ICORG), Imperial College London, London, UK
| | - Eduardo M. Normando
- Imperial College Healthcare NHS Trust (ICHNT), The Western Eye Hospital, London, UK
- The Imperial College Ophthalmic Research Group (ICORG), Imperial College London, London, UK
| | - Maria Francesca Cordeiro
- Imperial College Healthcare NHS Trust (ICHNT), The Western Eye Hospital, London, UK
- The Imperial College Ophthalmic Research Group (ICORG), Imperial College London, London, UK
- Department of Visual Neuroscience, Glaucoma and Retinal Neurodegeneration Group, UCL Institute of Ophthalmology, London, UK
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Vandewalle E, Vandenbroeck S, Stalmans I, Zeyen T. Comparison of ICare, Dynamic Contour Tonometer, and Ocular Response Analyzer with Goldmann Applanation Tonometer in Patients with Glaucoma. Eur J Ophthalmol 2018; 19:783-9. [PMID: 19787598 DOI: 10.1177/112067210901900516] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Affiliation(s)
| | - Sofie Vandenbroeck
- Department of Ophthalmology, University Hospitals Leuven
- Center for Health Services and Nursing Research, Katholieke Universiteit Leuven - Belgium
| | | | - Thierry Zeyen
- Department of Ophthalmology, University Hospitals Leuven
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Cheng L, Ding Y, Duan X, Wu Z. Ocular pulse amplitude in different types of glaucoma using dynamic contour tonometry: Diagnosis and follow-up of glaucoma. Exp Ther Med 2017; 14:4148-4152. [PMID: 29104631 PMCID: PMC5658696 DOI: 10.3892/etm.2017.5074] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2016] [Accepted: 03/24/2017] [Indexed: 11/05/2022] Open
Abstract
The aim of the present study was to compare the ocular pulse amplitude (OPA) in patients with different types of glaucoma using dynamic contour tonometry (DCT), to evaluate ocular and systemic factors associated with the OPA and to verify whether OPA measured by DCT is an independent predictor for glaucoma diagnosis. A total of 217 eyes of 217 participants in the following five groups were included in this cross-sectional study: Chronic angle closure glaucoma (CACG), primary open angle glaucoma, normal tension glaucoma (NTG), suspected open angle glaucoma (SOAG) and normal control (NC). The following tests were simultaneously performed during a single visit: Intra-ocular pressure (IOP), OPA, cup-to-disk (C/D) ratio, mean damage (MD) and loss variance (LV). OPAs were compared in each group. The association between OPA and IOP, age, C/D ratio, MD and LV was detected. OPA analysis prior to and after trabeculectomy was also performed to assess its prognostic value. Among the 217 individuals, the OPA was consistent with the IOP, both measured by DCT, along with the MD and LV. Patients with CACG and SOAG had higher OPA values than those with NTG and normal controls. Compared with patients aged >30 years, the OPA was significantly lower in younger patients, while they may not have been affected by different C/D ratios. After trabeculectomy, the OPA had significantly decreased compared with the values prior to surgery. In conclusion, the present study showed that the OPA is correlated with the IOP determined by DCT. CACG and SOAG patients had higher OPA values than patients with other types of glaucoma. OPA measured by DCT may be a predictor for glaucoma diagnosis and prognosis.
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Affiliation(s)
- Lingyan Cheng
- Department of Ophthalmology, Wuxi Second People's Hospital of Nanjing Medical University, Wuxi, Jiangsu 214000, P.R. China
| | - Yuzhi Ding
- Department of Ophthalmology, Zhongda Hospital, Medical School of Southeast University, Nanjing, Jiangsu 210009, P.R. China
| | - Xuanchu Duan
- Department of Ophthalmology, Xiangya No. 2 Hospital Affiliated to Central South University, Changsha, Hunan 410008, P.R. China
| | - Zhifeng Wu
- Department of Ophthalmology, Wuxi Second People's Hospital of Nanjing Medical University, Wuxi, Jiangsu 214000, P.R. China
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Akyol N, Kalkisim A, Turk A, Kola M, Imamoglu HI. Evaluation of the effects on choroidal thickness of bimatoprost 0.03% versus a brinzolamide 1.0%/timolol maleate 0.5% fixed combination. Cutan Ocul Toxicol 2017; 36:397-403. [PMID: 28376651 DOI: 10.1080/15569527.2017.1315128] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
Abstract
OBJECTIVE To investigate the effects of two different medical treatment options on choroidal thickness (CT) in cases of open-angle glaucoma (OAG). METHODS Sixty-seven eyes newly diagnosed with OAG and 52 healthy eyes constituting the control group were included in the study. Glaucomatous eyes were randomly divided into two subgroups; Group I was started on bimatoprost 0.03% and Group II on a brinzolamide 1.0%/timolol maleate 0.5% fixed combination (BTFC). Intraocular pressure (IOP), ocular pulse amplitude (OPA) and subfoveal CT measurements were performed in all eyes in the study before treatment and on weeks 2, 4 and 8 after treatment. RESULTS Mean initial IOP values in groups I and II and the control group were 25.5 ± 4.7, 25.1 ± 5.2 and 16.1 ± 2.9 mmHg, mean OPA values were 3.7 ± 1, 3.6 ± 1.4 and 2.4 ± 0.6 mmHg and mean CT values were 269.4 ± 83, 264.5 ± 84.4 and 320.1 ± 56.6 μm, respectively. Eight weeks after treatment, mean IOP values in Groups I and II and the control group were 18.3 ± 2.6, 18.1 ± 3.4 and 15.7 ± 2.9 mmHg, mean OPA values were 2.9 ± 1.2, 2.8 ± 1.5 and 2.3 ± 0.8 mmHg and mean CT values were 290.2 ± 87.3, 271.8 ± 82.5 and 319.3 ± 56.8 μm, respectively. No significant difference was determined in terms of the decrease in IOP and OPA obtained after treatment in Group I and Group II. However, a significant difference was observed between the two groups in terms of choroidal thickening after treatment. CONCLUSION The use of topical ocular hypotensive medication in eyes with OAG results in an increase in CT. This increase is relatively greater with bimatoprost 0.03% therapy compared to BTFC.
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Affiliation(s)
- Nurettin Akyol
- a Faculty of Medicine , Department of Ophthalmology, Karadeniz Technical University , Trabzon , Turkey
| | - Ahmet Kalkisim
- a Faculty of Medicine , Department of Ophthalmology, Karadeniz Technical University , Trabzon , Turkey
| | - Adem Turk
- a Faculty of Medicine , Department of Ophthalmology, Karadeniz Technical University , Trabzon , Turkey
| | - Mehmet Kola
- a Faculty of Medicine , Department of Ophthalmology, Karadeniz Technical University , Trabzon , Turkey
| | - Halil Ibrahim Imamoglu
- a Faculty of Medicine , Department of Ophthalmology, Karadeniz Technical University , Trabzon , Turkey
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Tejwani S, Dinakaran S, Joshi A, Shetty R, Sinha Roy A. A cross-sectional study to compare intraocular pressure measurement by sequential use of Goldman applanation tonometry, dynamic contour tonometry, ocular response analyzer, and Corvis ST. Indian J Ophthalmol 2016; 63:815-20. [PMID: 26669331 PMCID: PMC4730691 DOI: 10.4103/0301-4738.171956] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022] Open
Abstract
OBJECTIVE To study the correlation and effect of sequential measurement of intraocular pressure (IOP) with Goldmann applanation tonometer (GAT), ocular response analyzer (ORA), dynamic contour tonometer (DCT), and Corvis ST. SETTING AND DESIGN Observational cross-sectional series from the comprehensive clinic of a tertiary eye care center seen during December 2012. METHODS One hundred and twenty-five study eyes of 125 patients with normal IOP and biomechanical properties underwent IOP measurement on GAT, DCT, ORA, and Corvis ST; in four different sequences. Patients with high refractive errors, recent surgeries, glaucoma, and corneal disorders were excluded so as to rule out patients with evident altered corneal biomechanics. STATISTICAL ANALYSIS Linear regression and Bland-Altman using MedCalc software. RESULTS Multivariate analysis of variance with repeated measures showed no influence of sequence of device use on IOP (P = 0.85). Linear regression r2 between GAT and Corvis ST, Corvis ST and Goldmann-correlated IOP (IOPg), and DCT and Corvis ST were 0.37 (P = 0.675), 0.63 (P = 0.607), and 0.19 (P = 0.708), respectively. The Bland-Altman agreement of Corvis ST with GAT, corneal compensated IOP, and IOPg was 2 mmHg (-5.0 to + 10.3), -0.5 mmHg (-8.1 to 7.1), and 0.5 mmHg (-6.2 to 7.1), respectively. Intraclass correlation coefficient for repeatability ranged from 0.81 to 0.96. CONCLUSIONS Correlation between Corvis ST and ORA was found to be good and not so with GAT. However, agreement between the devices was statistically insignificant, and no influence of sequence was observed.
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Affiliation(s)
- Sushma Tejwani
- Department of Glaucoma, Narayana Nethralaya, Bengaluru, Karnataka, India
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11
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Abstract
PURPOSE The measurement of intraocular pressure (IOP) by Goldmann applanation tonometry (GAT) is based on assumptions about corneal parameters. To correct for variations in corneal curvature and thickness, a number of equations have been proposed. This study evaluates the in vivo accuracy of these equations from individuals with primary open-angle glaucoma and compared them with measurements taken using the Pascal dynamic contour tonometer (DCT), which makes no assumptions about the corneal geometry or biomechanics. PARTICIPANTS AND METHODS The study included 108 participants with primary open-angle glaucoma (47 male and 61 female) with an age range of 39 to 81 years. Participants were recruited from the Glaucoma Clinic at Wroclaw Medical University. A full ophthalmologic examination was conducted on all participants. Participants were divided into 3 groups depending on IOP as measured by GAT. Six formulae were applied and the results were compared with measurements taken with DCT. MAIN OUTCOME MEASURES To determine as to which formula provides the closest value to IOP measured with DCT. RESULTS For IOP values ≤29 mm Hg, 2 of the formulae showed the smallest and comparable mean differences and SDs between corrected IOP values obtained with GAT and those measured with DCT. For IOP≥30 mm Hg, the formula derived from the model of corneal applanation that takes into account corneal buckling showed the closest agreement with measurements taken using DCT. CONCLUSIONS Correction formulae provide widely varying results and their appropriateness can depend on the IOP values.
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12
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Bozic MM, Dukic ML, Stojkovic MZ. Spectral analysis of intraocular pressure pulse wave in ocular hypertensive and primary open angle glaucoma patients. Indian J Ophthalmol 2016; 64:114-7. [PMID: 27050344 PMCID: PMC4850804 DOI: 10.4103/0301-4738.179719] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022] Open
Abstract
Context: In attempt to find an alternative way to determine conversion from ocular hypertension to primary open angle glaucoma (POAG) (besides visual field and optic disc changes), we analyzed intraocular pressure (IOP) pulse wave in spectral domain. Aims: The aim of this study was to test the potential differences in spectral content of IOP pulse wave between ocular hypertension and POAG patients, which could indicate conversion. Settings and Design: Cross-sectional study designed to test the differences in the spectral content of pressure pulse wave between nontreated ocular hypertensive and nontreated, freshly diagnosed POAG patients. Methods: The total of 40 eyes of 40 subjects was included: 20 previously untreated ocular hypertensive patients, and 20 previously untreated POAG patients. Continuous IOP measuring gained by dynamic contour tonometry was submitted to fast Fourier transform signal analysis and further statistical data processing. Statistics Analysis Used: Ocular and systemic characteristics of the tested subjects were compared by analysis of variance appropriate for this study design. A P < 0.05 was considered to be statistically significant. Results: Higher spectral components of the IOP pulse wave was discerned up to the fifth harmonic in both of the tested groups. No statistically significant differences were found in any of the tested harmonic amplitudes. Conclusions: There are no differences in the spectral content of IOP pulse wave between ocular hypertensive and primary open angle glaucoma patients which could be indicative for conversion.
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Affiliation(s)
- Marija M Bozic
- Department of Glaucoma, Faculty of Medicine, University of Belgrade, Belgrade; Clinic of Ophthalmology, Clinical Center of Serbia, Belgrade, Serbia
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Levine DN, Bebie H. Phase and amplitude of spontaneous retinal vein pulsations: An extended constant inflow and variable outflow model. Microvasc Res 2016; 106:67-79. [PMID: 26997658 DOI: 10.1016/j.mvr.2016.03.005] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2015] [Revised: 02/21/2016] [Accepted: 03/12/2016] [Indexed: 11/16/2022]
Abstract
The constant inflow and variable outflow (CIVO) theory correctly predicts that spontaneous pulsation of the retinal veins will be visible close to the point where the vein exits the eye at the lamina cribrosa but will decrease rapidly in amplitude and become too small to see only a short distance upstream. However, the phase of vein oscillation relative to the oscillation of the intraocular pressure (IOP) predicted by CIVO has been unclear and controversial. We show that the CIVO model is indeterminate in predicting such phase relations. We propose a simple extension of the CIVO model that retains its basic equations but applies them to a larger domain that includes not only the intraocular (pre-laminar) portion of the vein but also the retrobulbar (post-laminar) portion of the vein behind the eye. We show that this extended CIVO model makes definite predictions about the phase of vein oscillation relative to the oscillation of IOP. This phase relationship is determined by the relative amplitude and phase of pulsations of the IOP and of the cerebrospinal fluid pressure (CSFP). If IOP and CSFP oscillate in phase, then the pre-laminar vein oscillates in phase with IOP when the amplitude of CSFP exceeds the amplitude of IOP but oscillates in counter phase with IOP when the amplitude of IOP exceeds that of CSFP. These relationships are modified when there is a phase difference between the oscillations of IOP and CSFP. When CSFP leads IOP, the phase of vein oscillation is advanced if the amplitude of CSFP exceeds that of IOP and is delayed if the amplitude of IOP exceeds that of CSFP. The result in each case is that maximum vein size occurs during the rising phase of IOP (ocular systole). We conclude that the driving force of vein oscillation is the difference between the oscillations of IOP and CSFP. The phase of this difference determines the phase relationships above. We show that additional delays in the phase of venous pulsation relative to that of IOP are induced by constriction of the vein within the lamina cribrosa and by recording the vein pulsations upstream from the lamina cribrosa. The amplitude of vein oscillation is proportional to the amplitude of the driving force and to the venous capacitance. Loss of spontaneous retinal vein pulsation with increase in mean CSFP is determined primarily by reduced venous capacitance. Increased amplitude of pulsation may occur when IOP is increased. It is the result of increased venous capacitance and possibly increased driving force of the pulsation. However, in chronic glaucoma the increase in capacitance may be counteracted by venous outflow obstruction, and the increase in driving force may be counteracted by reduced ocular blood flow. As a result retinal vein oscillation may be reduced in amplitude.
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Affiliation(s)
- David N Levine
- Department of Neurology, New York University School of Medicine, 240 East 38th Street, Suite 20-02, New York, NY 10016, USA.
| | - Hans Bebie
- Institute for Theoretical Physics, University of Berne, CH-3012 Berne, Switzerland.
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Abstract
This review is focused on continuous IOP monitoring using telemetry systems in the nonhuman primate (NHP), presented in the context that IOP fluctuations at various timescales may be involved in glaucoma pathogenesis and progression. We use glaucoma as the primary framework to discuss how the dynamic nature of IOP might change with age, racial heritage, and disease in the context of glaucoma susceptibility and progression. We focus on the limited work that has been published in IOP telemetry in NHPs, as well as the emerging data and approaches. We review the ongoing efforts to measure continuous IOP, and the strengths, weaknesses and general pitfalls of the various approaches.
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Affiliation(s)
- J Crawford Downs
- Department of Ophthalmology, University of Alabama at Birmingham School of Medicine, Birmingham, AL, USA.
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Asejczyk-Widlicka M, Krzyżanowska-Berkowska P, Kowalska M, Iskander DR. Clinical utility of spectral analysis of intraocular pressure pulse wave. BMC Ophthalmol 2014; 14:30. [PMID: 24620786 PMCID: PMC3975190 DOI: 10.1186/1471-2415-14-30] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2013] [Accepted: 03/03/2014] [Indexed: 12/01/2022] Open
Abstract
Background To evaluate the clinical utility of spectral analysis of intraocular pressure pulse wave in healthy eyes of a control group (CG), patients having glaucomatous optic disc appearance or ocular hypertension, and patients with primary open angle glaucoma or primary angle closure glaucoma. Methods This is a prospective study that enrolled 296 patients from a single glaucoma clinic. Age matched CG consisted of 62 individuals. Subjects underwent comprehensive clinical diagnostic procedures including intraocular pressure (IOP) measurement with dynamic contour tonometry (DCT) and Goldmann applanation tonometry (GAT). DCT time series were analyzed with custom written software that included signal preprocessing, filtering and spectral analysis. An amplitude and energy content analysis, which takes into account non-stationarity of signals but also provides methodology that is independent of IOP and ocular pulse amplitude (OPA) levels, was applied. Spectral content up to the 6th harmonic of the pressure pulse wave was considered. Statistical analyses included descriptive statistics, normality test, and a multicomparison of medians for independent groups using Kruskal-Wallis test. Results GAT IOP showed statistical significance (Kruskal-Willis test p < 0.05) for three out of 10 considered multiple comparisons, DCT IOP and OPA showed statistically significant results in five and seven cases, respectively. Changes in heart rate and central corneal thickness between the groups were statistically significant in two cases. None of the above parameters showed statistically significant differences between CG and the suspects with glaucomatous optic disc appearance (GODA). On the other hand, spectral analysis showed statistically significant differences for that case. Conclusions Spectral analysis of the DCT signals was the only method showing statistically significant differences between healthy eyes and those of GODA suspects.
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Affiliation(s)
- Magdalena Asejczyk-Widlicka
- Faculty of Materials, Strength and Welding, Wroclaw University of Technology, Smoluchowskiego 25, 50-372 Wroclaw, Poland.
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Siesky BA, Harris A, Amireskandari A, Marek B. Glaucoma and ocular blood flow: an anatomical perspective. EXPERT REVIEW OF OPHTHALMOLOGY 2014. [DOI: 10.1586/eop.12.41] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
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Bochmann F, Kaufmann C, Thiel MA. Dynamic contour tonometry versus Goldmann applanation tonometry: challenging the gold standard. EXPERT REVIEW OF OPHTHALMOLOGY 2014. [DOI: 10.1586/eop.10.68] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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Keel S, Malesic L, Chan SP. Diurnal variation in central corneal thickness and intraocular pressure in eyes with pseudoexfoliation syndrome without glaucoma. Indian J Ophthalmol 2014; 62:1072-1076. [PMID: 25494249 PMCID: PMC4290197 DOI: 10.4103/0301-4738.146755] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Abstract
Aim: The aim was to ascertain if any differences exist in diurnal central corneal thickness (CCT) and intra-ocular pressure (IOP) between eyes with pseudoexfoliation (PXF) syndrome without glaucoma and eyes with no ocular pathology. A secondary aim was to determine whether there was a significant relationship between CCT and IOP. Settings and Design: This study was a prospective design conducted within a hospital setting. Materials and Methods: The experimental group consisted of seven participants with bilateral PXF (14 eyes) and the control group comprised of 15 participants (30 eyes). Testing included CCT and IOP measured at four different times on one given day (8.00 a.m.; 11 a.m.; 2 p.m. and 5 p.m.). Statistical Analysis: The data were analyzed with the generalized linear latent mixed model. Results: PXF eyes displayed a significantly thinner overall mean CCT (520 μm) compared to controls (530 μm). Furthermore, a significant reduction in CCT and IOP occurred in the PXF group from 8 a.m. to 5 p.m. The mean overall IOP in PXF eyes was significantly lower than the control group. A significant association between IOP and CCT was also found in PXF eyes. Conclusions: Displaying a significantly thinner mean CCT highlights the importance of measuring CCT in an ophthalmic clinical setting as to avoid falsely underestimated IOP measurements in such a high-risk glaucoma population. Furthermore, a statistically significant correlation between IOP and CCT in PXF eyes suggests that the reduction in CCT that occurred in PXF eyes between 8 a.m. and 5 p.m. may be partly responsible for the reduction in IOP measurements.
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Affiliation(s)
- Stuart Keel
- Department of Clinical Vision Sciences, La Trobe University, Bundoora, Victoria, Australia,
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Schweier C, Hanson JVM, Funk J, Töteberg-Harms M. Repeatability of intraocular pressure measurements with Icare PRO rebound, Tono-Pen AVIA, and Goldmann tonometers in sitting and reclining positions. BMC Ophthalmol 2013; 13:44. [PMID: 24006952 PMCID: PMC3844420 DOI: 10.1186/1471-2415-13-44] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2012] [Accepted: 08/30/2013] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Icare PRO (ICP) is a new Rebound tonometer that is able to measure intraocular pressure (IOP) in both sitting and reclining positions. In this study, the gold standard Goldmann tonometer (GAT) was compared to ICP and Tono-Pen AVIA (TPA). Hypothesis was that repeatability of GAT is superior to ICP and TPA. METHODS 36 eyes of 36 healthy caucasian individuals, 13 male and 26 females, 17 right and 19 left eyes have been included in this prospective, randomized, cross-sectional study. The study was conducted at a single site (Dept. of Ophthalmology, University Hospital Zurich, Switzerland). Primary outcome measures were Intraclass correlation coefficients (ICC) and coefficients of variation (COV) and test-retest repeatability as visualized by Bland-Altman analysis. Secondary outcome measures were IOP in sitting (GAT, ICP and TPA) and in reclining (ICP and TPA) position. RESULTS Mean IOP measured by GAT was 14.9 ± 3.5 mmHg. Mean IOP measured by ICP was 15.6 ± 3.1 mmHg (with TPA 14.8 ± 2.7 mmHg) in sitting and 16.5 ± 3.5 mmHg (with TPA 17.0 ± 3.0 mmHg) in reclining positions. COVs ranged from 2.9% (GAT) to 6.9% (ICP reclining) and ICCs from 0.819 (ICP reclining) to 0.972 (GAT). CONCLUSIONS Repeatability is good with all three devices. GAT has higher repeatability compared to the two tested hand-held devices with lowest COVs and highest ICCs. IOP was higher in the reclining compared to the sitting position. TRIAL REGISTRATION The study was registered to the Clinical Trials Register of the US National Institute of Health, NCT01325324.
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Affiliation(s)
- Caterina Schweier
- Department of Ophthalmology, UniversityHospital Zurich, Frauenklinikstrasse 24, 8091 Zurich, Switzerland.
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20
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Figueiredo BP, Cronemberger S, Kanadani FN. Correlation between ocular perfusion pressure and ocular pulse amplitude in glaucoma, ocular hypertension, and normal eyes. Clin Ophthalmol 2013; 7:1615-21. [PMID: 23966769 PMCID: PMC3745293 DOI: 10.2147/opth.s44523] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022] Open
Abstract
Background The purpose of this study was to investigate the correlation between ocular perfusion pressure and ocular pulse amplitude in glaucoma, ocular hypertension, and normal eyes. Methods Ninety eyes from 90 patients were included. Thirty patients had been recently diagnosed with glaucoma and had no previous history of treatment for ocular hypotension, 30 had elevated intraocular pressure (IOP) without evidence of glaucoma, and 30 had normal IOP (<21 mmHg) with no detectable glaucomatous damage. Goldmann applanation tonometry (GAT), dynamic contour tonometry (DCT), blood pressure measurement, pachymetry, Humphrey visual field, and routine ophthalmic examination was performed in each patient. Ocular perfusion pressure was calculated as the difference between mean arterial pressure and IOP. The ocular pulse amplitude was given by DCT. The Pearson correlation coefficient was used to compare the glaucomatous and ocular hypertensive groups, and comparisons with the normal IOP group were done using the Spearman’s rank correlation coefficient. Results Mean IOP by DCT was 22.7 ± 4.3 mmHg in the glaucoma group, 22.3 ± 2.8 mmHg in the ocular hypertension group, and 14.3 ± 1.6 mmHg in the control group. Mean IOP by GAT was 19.0 ± 5.1 mmHg for glaucoma, 22.4 ± 2.1 mmHg for ocular hypertension, and 12.9 ± 2.2 mmHg for controls. Mean ocular pulse amplitude was 3.4 ± 1.2 mmHg in the glaucoma group, 3.5 ± 1.2 mmHg in the ocular hypertension group, and 2.6 ± 0.9 mmHg in the control group. Mean ocular perfusion pressure was 46.3 ± 7.9 mmHg in the glaucoma group, 46.3 ± 7.9 mmHg in the ocular hypertension group, and 50.2 ± 7.0 mmHg in controls. No significant correlation between ocular perfusion pressure and ocular pulse amplitude was found in any of the groups (P = 0.865 and r = −0.032, P = 0.403 and r = −0.156, P = 0.082 and ρ = −0.307 for glaucoma, ocular hypertension, and normal eyes, respectively). Conclusion There is no significant correlation between ocular perfusion pressure and ocular pulse amplitude values in glaucoma, ocular hypertension, or normal eyes. IOP values measured by GAT correlate with those measured by DCT.
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Affiliation(s)
- Bruno P Figueiredo
- Departments of Ophthalmology, Federal University of Minas Gerais, Belo Horizonte, Brazil ; Departments of Ophthalmology, Glaucoma and Cataract Service, Santa Casa of Belo Horizonte, Brazil
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Kim YJ, Lee KS, Lee JR, Na JH, Choi J, Han S, Kook MS. Ocular pulse amplitude as a dynamic parameter and its relationship with 24-h intraocular pressure and blood pressure in glaucoma. Exp Eye Res 2013; 115:65-72. [PMID: 23797045 DOI: 10.1016/j.exer.2013.06.010] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2013] [Revised: 06/06/2013] [Accepted: 06/07/2013] [Indexed: 10/26/2022]
Abstract
Abnormal ocular blood flow (OBF) has been suspected as one of the underlying mechanisms of glaucoma. The ocular pulse amplitude (OPA) is considered a possible surrogate parameter for ocular blood flow (OBF) measurement and has been studied in its association with glaucoma. Although there have been several studies that reported various ocular and systemic factors in association with OPA, all of these studies were based on a single measurement of these factors as well as OPA. The purpose of this study was to determine the 24-h (h) dynamic variability and any associations between OPA and intraocular pressure (IOP) and blood pressure (BP) variables using 24-h data collected from untreated patients with normal-tension glaucoma (NTG). One hundred and forty-four patients with NTG were consecutively enrolled. All patients underwent 24-h monitoring of IOP, OPA, and BP variables. A cosinor model was used to describe the patterns and statistical significance of the 24-h OPA rhythm, as well as the IOP and BP variables. Associations between 24-h OPA data, IOP and BP variables, and ocular and demographic factors were also assessed using the generalized estimating equation. Over the course of 24-h, OPA (p = 0.007) demonstrated significant dynamic diurnal rhythms that were similar to the other dynamic variables (all p < 0.05). Based on the 24-h data, IOP (p < 0.001), arterial pulse pressure (p = 0.034), and the spherical equivalent (p < 0.001) positively correlated with the OPA, whilst male sex (p < 0.001) negatively correlated with the OPA. These results indicate that OPA is primarily influenced by IOP as well as arterial pulse pressure, spherical equivalent, and gender. In conclusion, OPA is a dynamic ocular parameter that demonstrates a 24-h short-time fluctuation in NTG patients.
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Affiliation(s)
- Yoon Jeon Kim
- Department of Ophthalmology, University of Ulsan, College of Medicine, Asan Medical Center, 388-1 Pungnap-2-dong, Songpa-gu, Seoul 138-736, Republic of Korea
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Moghimi S, Torabi H, Fakhraie G, Nassiri N, Mohammadi M. Dynamic contour tonometry in primary open angle glaucoma and pseudoexfoliation glaucoma: factors associated with intraocular pressure and ocular pulse amplitude. Middle East Afr J Ophthalmol 2013; 20:158-62. [PMID: 23741135 PMCID: PMC3669493 DOI: 10.4103/0974-9233.110606] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022] Open
Abstract
Purpose: To compare the intraocular pressures (IOP) and ocular pulse amplitudes (OPAs) in patients with primary open-angle glaucoma (POAG) and pseudoexfoliation glaucoma (PXG), and to evaluate ocular and systemic factors associated with the OPA. Materials and Methods: In this prospective study, on 28 POAG and 30 PXG patients, IOP was measured with the Goldmann applanation tonometry (GAT) and the Pascal dynamic contour tonometry (DCT). Other measurements included central corneal thickness (CCT), vertical cup-to-disc ratio (CDR), and systolic and diastolic blood pressure. Statistical significance was defined as P < 0.05. Results: In each of the POAG and PXG groups, GAT IOP was correlated with CCT (r = 0.40, P = 0.03 and r = 0.35, P = 0.05, respectively), whereas DCT IOP and CCT were not correlated. In all patients and in the POAG group, OPA was positively correlated with DCT IOP (r = 0.39, P = 0.002). OPA was not correlated with CCT in the POAG (P = 0.80), nor in the PXG (P = 0.20) group, after adjusting for DCT IOP. When corrected for DCT IOP and CCT, there was a significant negative correlation between OPA and vertical CDR in all patients (r = −0.41, P = 0.002). There was no significant difference in OPA between groups (P = 0.55), even when OPA was adjusted for IOP and systolic and diastolic pressure (P = 0.40), in a linear regression model. Conclusion: DCT IOP and OPA are not correlated with CCT. There is no significant difference between the OPA of PXG and POAG eyes. OPA is correlated with DCT IOP, and is lower in eyes with more advanced glaucomatous cupping.
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Affiliation(s)
- Sasan Moghimi
- Department of Ophthalmology, Farabi Eye Hospital, Tehran University of Medical Sciences, Tehran, Iran
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Colás-Tomás T, Prieto-Del Cura M, Villafruela-Güemes I, Clariana-Martín A, Valdivia-Pérez A. [Comparison of dynamic contour tonometry, Goldmann and pneumotonometer in ocular hypertension patients and their relationship to pachymetry and ocular pulse amplitude]. ARCHIVOS DE LA SOCIEDAD ESPANOLA DE OFTALMOLOGIA 2012; 87:401-6. [PMID: 23121701 DOI: 10.1016/j.oftal.2012.05.004] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/22/2011] [Revised: 03/20/2012] [Accepted: 05/23/2012] [Indexed: 11/27/2022]
Abstract
PURPOSE To determine the relationship between dynamic contour tonometry (DCT), Goldmann applanation tonometry (GAT) and pneumotonometry (PNT) in ocular hypertension patients (OHT) and their relationship to central corneal thickness (CCT) and ocular pulse amplitude (OPA). METHODS Sixty patients (101 eyes) with intraocular pressure (IOP) ≥21 mmHg using GAT and normal appearing optic nerve heads and normal visual fields were included. The following tests were performed simultaneously during a single visit: IOP using DCT, GAT and PNT, OPA using DCT and CCT using ultrasound pachymetry. We studied the difference IOP between these 3 tonometers using Wilcoxon non-parametric test and the effect of CCT on IOP and OPA, as well as the relationship between OPA and IOP using Spearman correlation coefficient. RESULTS The median PNT IOP was 24 mmHg (Inter-quartile range [IQR]: 22-26), median GAT IOP was 22 mmHg (IQR: 22-24), and median DCT IOP was 28.2 mmHg (IQR: 24.1-30.7). PNT and DCT had higher IOP values than GAT (median 2 mmHg and 6.2 mmHg, respectively). Mean CCT was 594.5 μm (SD 30.0). GAT IOP and DCT IOP showed an increase with increased corneal thickness (r:0.209; P=.036 and r:0.195; P=.051, respectively). PNT IOP did not change with CCT (r:0.15; P=.12). The median OPA was 4.8 mmHg (IQR: 3.6-6.1), and significantly increased with GAT IOP (r:0,38; P<.001) and with CCT (r:0.287; P=.004). This association was unclear with IOP PNT and IOP DCT (r:0.067; P=.50 and r:0,17, P=.08, respectively). CONCLUSIONS DCT and PNT IOP values were higher than GAT IOP measurements in ocular hypertension patients. GAT IOP showed a significant increase with increased corneal thickness. Increased OPA seems to correlate with increased CCT and IOP, particularly if GAT is used.
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Affiliation(s)
- T Colás-Tomás
- Servicio de Oftalmología, Hospital del Tajo, Aranjuez, Madrid, España.
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Choi J, Lee J, Park SB, Lee KS, Sung KR, Kook MS. Factors affecting ocular pulse amplitude in eyes with open angle glaucoma and glaucoma-suspect eyes. Acta Ophthalmol 2012; 90:552-8. [PMID: 20560890 DOI: 10.1111/j.1755-3768.2010.01954.x] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
PURPOSE To investigate the associations between ocular pulse amplitude (OPA) as measured by dynamic contour tonometry (DCT) and ocular and systemic factors in patients with open angle glaucoma (OAG) and in glaucoma suspects. METHODS One hundred and seventy-three glaucoma-suspect patients were consecutively enrolled. All subjects underwent intraocular pressure (IOP) measurement by DCT and Goldmann applanation tonometry (GAT), OPA measurement by DCT, Humphrey visual field (HVF) examination and central corneal thickness measurements. Arterial pulse amplitude (APA) and ocular perfusion pressure (OPP) were defined as the difference between systolic and diastolic BP and the difference between mean arterial pressure and IOP, respectively. All subjects also completed a systemized questionnaire on systemic vascular morbidities. RESULTS Seventy-four eyes were diagnosed with OAG, based on HVF results. The overall mean CCT was 538.2±37.6 μm. In all 173 eyes, OPA was associated with spherical equivalent (SE, p<0.001) and with IOP by GAT (p=0.013) by multivariate analysis. Multivariate analysis of the 77 subgroup eyes of patients for whom BP parameters were available also revealed that OPA was associated with SE (p=0.007) and with IOP by GAT (p<0.001). When the subjects were classified into the groups with low, intermediate and high cardiovascular risk based on the questionnaire, there was no difference in OPA among these groups (p>0.05). CONCLUSIONS Ocular pulse amplitude was associated with IOP measured by GAT and SE in patients with OAG and in glaucoma suspects. There was neither significant correlation between systemic hemodynamic parameters and OPA, nor difference of OPA in patients with different cardiovascular risk. OPA is primarily a measure of pressure, and there are certain limitations towards its use as a hemodynamic index.
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Knecht PB, Menghini M, Bachmann LM, Baumgartner RW, Landau K. The ocular pulse amplitude as a noninvasive parameter for carotid artery stenosis screening: a test accuracy study. Ophthalmology 2012; 119:1244-9. [PMID: 22361314 DOI: 10.1016/j.ophtha.2011.12.040] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2011] [Revised: 12/21/2011] [Accepted: 12/21/2011] [Indexed: 10/28/2022] Open
Abstract
PURPOSE To investigate a potential correlation between the ocular pulse amplitude (OPA; i.e., the intraocular pressure difference between the systolic and diastolic phases of the heartbeat) and the severity of carotid artery stenosis (CAS) and to test its role as a screening parameter for CAS during routine ophthalmic examination. DESIGN Test accuracy study. PARTICIPANTS Patients referred for color duplex ultrasound examination of the extra- and intracranial cerebral arteries were enrolled consecutively. METHODS We measured OPA on both eyes by dynamic contour tonometry. Multivariate analyses were performed with risk factors for CAS (age, total cholesterol, low-density lipoprotein, and triglycerides) to compare the diagnostic value of OPA measurements with other non- or minimally invasive screening parameters. MAIN OUTCOME MEASURES The difference between OPA measurements in patients with no (<50%) and patients with severe CAS (>70%) as well as the value of OPA measurements to predict the severity of CAS taking further risk factors of CAS into consideration. RESULTS One hundred thirty-four eyes of 67 patients (25 women, 42 men) with a mean age of 67±13 years (range, 25-87) were included. The means of the OPA values of those patients showing no CAS (<50%) differed significantly (P = 0.036) from those with a stenosis of ≥70%. The multivariate model produced a statistically significant odds ratio (0.46; P = 0.007) for CAS of ≥70%. CONCLUSIONS The results of the present study provide proof of principle that the OPA is reduced in patients with CAS and may be used as a noninvasive, inexpensive, readily available, and unconfounded screening parameter to detect CAS and possibly to reduce the incidence of stroke. FINANCIAL DISCLOSURE(S) The authors have no proprietary or commercial interest in any of the materials discussed in this article.
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Affiliation(s)
- Pascal B Knecht
- University Hospital Zurich, Department of Ophthalmology, Zurich, Switzerland.
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The effect of thin, thick, and normal corneas on Goldmann intraocular pressure measurements and correction formulae in individual eyes. Ophthalmology 2011; 119:443-9. [PMID: 22035576 DOI: 10.1016/j.ophtha.2011.07.058] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2011] [Revised: 07/28/2011] [Accepted: 07/29/2011] [Indexed: 11/23/2022] Open
Abstract
OBJECTIVE To evaluate the usefulness of the central corneal thickness (CCT)-based correction formulae for stratified CCT groups, with intraocular pressure (IOP) from the Pascal dynamic contour tonometer (PDCT) as the reference standard. DESIGN Retrospective case series. PARTICIPANTS Two hundred eighty-nine patients attending a specialist glaucoma practice and a mixture of normal subjects and subjects with confirmed glaucomatous optic neuropathy. METHODS Intraocular pressure was measured using PDCT, Goldmann applanation tonometry (GAT), and the Ocular Response Analyzer (ORA; Reichert Corp, Buffalo, NY). The GAT readings were obtained before automated readings and were adjusted for CCT using 4 different correction formulae. Discrepancies between GAT and CCT-corrected GAT readings were evaluated after stratification into thin, intermediate, and thick CCT groups. The IOP measurements from GAT, the ORA, and CCT-adjusted IOP were compared against PDCT IOP measurements using Bland-Altman analysis. MAIN OUTCOME MEASURES Mean, 95% limits of agreement, and proportion of patients with IOP difference of 20% or more between PDCT IOP and each of GAT IOP, Goldmann-correlated IOP (IOPg), corneal-compensated IOP (IOPcc), and adjusted IOP using CCT-based correction formulae. RESULTS Average PDCT IOP values were higher than GAT, IOPg, IOPcc, and CCT-adjusted IOP. The GAT IOP readings demonstrated poor agreement with PDCT IOP (95% limits of agreement, ± 4.7 mmHg); however, IOPg, IOPcc, and adjustment of GAT IOP with CCT-based formulae resulted in even poorer agreement (range of 95% limits of agreement, ± 5.1 to 6.7 mmHg). If PDCT was used as the reference standard, there was a 26% to 39% risk of making an erroneous IOP adjustment of magnitude of 20% or more at all levels of CCT. This risk was greatest in the patients with thicker corneas (CCT, ≥568 μm). CONCLUSIONS Adjusting IOP using CCT-based formulae resulted in poorer agreement with PDCT IOP when compared with unadjusted G AT IOP. If PDCT is the closest measure we have to intracameral IOP, there is a risk of creating clinically significant error after adjustment of GAT IOP with CCT-based correction formulae, especially in thicker corneas. This study suggests that although CCT may be useful in population analyses, CCT-based correction formulae should not be applied to individuals.
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Assessment of Factors Affecting the Difference in Intraocular Pressure Measurements Between Dynamic Contour Tonometry and Goldmann Applanation Tonometry. J Glaucoma 2011; 20:482-7. [DOI: 10.1097/ijg.0b013e3181efbe8f] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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Ang GS, Nicholas S, Wells AP. Poor utility of intraocular pressure correction formulae in individual glaucoma and glaucoma suspect patients. Clin Exp Ophthalmol 2011; 39:111-8. [PMID: 20973896 DOI: 10.1111/j.1442-9071.2010.02445.x] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
BACKGROUND To compare Pascal dynamic contour tonometry (DCT) measurements with Goldmann applanation tonometry (GAT) readings after adjustment with correction formulae in a population of Caucasian glaucoma and glaucoma suspect patients. DESIGN Retrospective cross-sectional case series in a specialist glaucoma practice. PARTICIPANTS Consecutive glaucoma and glaucoma suspect Caucasian patients. METHODS Case notes review of the GAT and DCT intraocular pressure (IOP) measurements from patients who presented on a non-acute basis over a 30-month period. The GAT measurement was adjusted with six different correction formulae. Agreement between GAT IOP, adjusted GAT IOP and DCT IOP was evaluated with the Bland-Altman analysis. MAIN OUTCOME MEASURES Agreement between GAT IOP (both unadjusted and adjusted) and DCT IOP. RESULTS Data from 200 patients with a mean age of 58.4 (±12.7) years were analysed. The mean central corneal thickness was 554.8 (±36.9) µm and the mean corneal hysteresis was 9.8 (±1.9) mm Hg. Sixty five (32.5%) had confirmed glaucomatous optic neuropathy. GAT IOP demonstrated poor agreement with DCT IOP. GAT IOP was on average 2.1 mm Hg less than DCT IOP. None of the six correction formulae resulted in improved agreement with DCT IOP. General linear model analysis found no statistically significant measurement differences between the glaucoma and glaucoma suspect groups. CONCLUSIONS GAT demonstrated poor agreement with DCT, and agreement did not improve after adjustment with correction formulae. Our results suggest that correction formulae for GAT IOP are unsuitable to clinically approximate 'true' IOP in Caucasian glaucoma and glaucoma suspect patients.
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Affiliation(s)
- Ghee S Ang
- Capital Eye Specialists, Wellington, New Zealand.
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Insull E, Nicholas S, Ang GS, Poostchi A, Chan K, Wells A. Optic disc area and correlation with central corneal thickness, corneal hysteresis and ocular pulse amplitude in glaucoma patients and controls. Clin Exp Ophthalmol 2011; 38:839-44. [PMID: 20653690 DOI: 10.1111/j.1442-9071.2010.02373.x] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
BACKGROUND To examine the relationships between optic disc area and parameters measured at the cornea; central corneal thickness (CCT), corneal hysteresis (CH) and ocular pulse amplitude (OPA) in glaucoma subjects and controls. METHODS In this prospective experimental study, patients underwent measurement of CCT, OPA, CH and optic disc imaging with the Heidelberg Retina Tomograph II (HRT-II). Pearson's correlation coefficient was calculated to assess the associations between optic disc area and CCT, OPA and CH. RESULTS A total of 100 patients, 38 with glaucoma and 62 controls were examined. In a univariate analysis of this group, CCT and CH were significantly lower in glaucoma patients (P = 0.01). CCT was inversely correlated with optic disc surface area (Pearson's correlation coefficient r = -0.200; P = 0.05). This inverse correlation did not achieve statistical significance when glaucoma patients and controls were analysed separately. There was no statistically significant association between optic disc area and OPA or CH. CONCLUSIONS There was an inverse relationship between CCT and optic disc area in this study group. No association was found between optic disc area and OPA or CH.
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Affiliation(s)
- Elizabeth Insull
- Wellington Eye Clinic, Capital and Coast District Health Board, Wellington, New Zealand
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Berisha F, Findl O, Lasta M, Kiss B, Schmetterer L. A study comparing ocular pressure pulse and ocular fundus pulse in dependence of axial eye length and ocular volume. Acta Ophthalmol 2010; 88:766-72. [PMID: 20337602 DOI: 10.1111/j.1755-3768.2009.01577.x] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
PURPOSE There is a long-standing discussion about whether myopia is associated with decreased choroidal blood flow, as suggested by pneumotonometric measurements of pulsatile ocular blood flow (POBF). However, it has been noted previously that calculations of POBF depend on intraocular volume. METHODS In the present study we investigated this volume dependence through the comparison of ocular pressure pulse and ocular fundus pulse. Fifty-one healthy participants with different refractive errors participated in the study. Pulse amplitude (PA) and POBF were measured using pneumotonometry. Fundus pulsation amplitude (FPA) was measured with laser interferometry. Axial eye length (AEL) was measured with partial coherence interferometry. A mathematical model was used to calculate choroidal volume changes based on FPA. The ocular pressure pulse was converted into pulse volume (PV) according to the standard procedure used for pneumotonometry. RESULTS PA and POBF were found to decrease with increasing axial length (r = -0.55, p < 0.001 and r = -0.57, p < 0.001, respectively). A similar relationship existed for PV (r = -0.57, p < 0.001) and FPA (r = -0.46, p = 0.001). In addition, there was a significant association between PV and choroidal volume change during the cardiac cycle (r = 0.61, p < 0.001). CONCLUSION The present study confirms experimentally that PA, FPA and POBF are dependent on ocular volume and indicates that the pulsatile component of ocular blood flow is not reduced in myopic patients. Accordingly, the relationship between AEL and POBF described previously appears to be a consequence of different ocular volumes. Our findings have important implications for studies using PA or POBF.
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Affiliation(s)
- Fatmire Berisha
- Department of Clinical Pharmacology, Medical University of Vienna, Austria
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Ocular pulse amplitude and associated glaucomatous risk factors in a healthy Hispanic population. OPTOMETRY (ST. LOUIS, MO.) 2010; 81:408-13. [PMID: 20655499 DOI: 10.1016/j.optm.2010.02.012] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/21/2009] [Revised: 02/05/2010] [Accepted: 02/12/2010] [Indexed: 11/21/2022]
Abstract
BACKGROUND With increasing evidence that vascular risk factors play a role in the development of glaucoma, it is critical to be familiar with factors related to intraocular blood flow, such as the ocular pulse amplitude (OPA). This study evaluates OPA and factors related to it in a healthy, Hispanic population. METHODS Refractive error, corneal curvature, Goldmann applanation tonometry (GAT), dynamic contour tonometry (DCT), OPA, axial length, and central corneal thickness (CCT) measurements were obtained on 104 Hispanic subjects recruited from the community. RESULTS OPA ranged from 0.7 to 4.7 mmHg (mean, 2.1 +/- 0.8 mmHg) and showed a significant correlation with refractive error, axial length, GAT, and DCT (r=0.250, -0.358, 0.460, 0.378; P=0.011, <0.001, <0.001, and <0.001, respectively). Mean intraocular pressure with GAT was 15.6 mmHg. Mean CCT was 541.2 microm. The average refractive error was 0.75 diopters (D) of myopia, with 25% having >1.00 D myopia. CONCLUSION Normal OPA values have not been studied in Hispanic populations. OPA is thought to provide information regarding ocular blood flow; however, more studies are needed to determine its significance in glaucoma treatment.
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[Mobile intraocular pressure measurement. From palpation to initial clinical experience with the handheld dynamic contour tonometer]. Ophthalmologe 2010; 107:676-8, 680-2. [PMID: 20571809 DOI: 10.1007/s00347-010-2175-y] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
Abstract
Goldmann applanation tonometry is still the gold standard of intraocular pressure measurement (IOP) and an essential part in the diagnosis of glaucoma. Applanation tonometry is usually performed on a sitting patient at the slit lamp. However, under certain circumstances it is necessary to measure the IOP outside the office setting. With handheld devices the measuring procedure is brought to bedside and surgery theatres, as well as to patients who are not able to sit behind the slit lamp. The dynamic contour tonometer (DCT) represents a new method of direct IOP measurement. Its physical principle is based on piezo-electronic contour matching tonometry and is claimed to be less dependent on biochemical properties of the cornea. Besides the IOP, the ocular pulse amplitude can also be measured. Until now, the DCT had been available as a slit lamp mounted device. In this report, we present a portable prototype of the device. In comparison with the Perkins tonometer and the TONO-PEN XL, the handheld DCT shows smaller intra- and inter-examiner variability. Additionally, the device offers the unique possibility to display the ocular pulse amplitude while the patient is in a horizontal position.
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Intraocular pressure and ocular pulse amplitude variations during the Valsalva maneuver. Graefes Arch Clin Exp Ophthalmol 2010; 248:1183-6. [DOI: 10.1007/s00417-010-1359-0] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2009] [Revised: 02/23/2010] [Accepted: 03/05/2010] [Indexed: 10/19/2022] Open
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Comparison of three methods of intraocular pressure measurement and their relation to central corneal thickness. Eye (Lond) 2010; 24:1165-70. [PMID: 20150923 DOI: 10.1038/eye.2010.11] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022] Open
Abstract
PURPOSE The purpose of this study was to compare the reliability of the 'gold standard' Goldmann applanation tonometer (GAT), with that of the ocular response analyser (ORA), and the dynamic contour tonometer (DCT). PATIENTS AND METHODS A total of 694 subjects were recruited to participate from the TwinsUK (UK Adult Twin Registry) at St Thomas' Hospital, London. Intraocular pressure (IOP) was measured using GAT, ORA, and the DCT. The agreement between the three methods was assessed using the Bland-Altman method. Repeatability coefficients and coefficient of variation between first and second readings of the same eye were used to assess reliability. RESULTS Mean age was 57.5 years (SD, 13.1; range, 16.1-88.5). The mean IOPs, calculated using the mean of two readings from the right eye were as follows: Goldmann (GAT), 14.1+/-2.8 mm Hg; IOPg (ORA), 15.9+/-3.2 mm Hg; IOPcc (ORA), 16.6+/-3.2 mm Hg; and DCT, 16.9+/-2.7 mm Hg. The 95% limits of agreement were for ORA (IOPcc): GAT, -2.07 to 7.18 mm Hg; for DCT: GAT, -0.49 to 6.21 mm Hg; and for DCT: ORA (IOPcc), -3.01 to 4.85 mm Hg. Coefficients of variation for the three tonometers were GAT, 8.3%; ORA, 8.2%; DCT, 6.3%. The repeatability coefficients were 3.4 mm Hg for GAT, 3.57 mm Hg for ORA and 3.09 mm Hg for DCT. GAT and ORA (IOPg) readings showed a positive correlation with central corneal thickness (P<0.005). CONCLUSIONS This study found similar reliability in all three tonometers. Bland-Altman plots showed the three instruments to have 95% limits of agreement outside the generally accepted limits, which means they are not interchangeable. GAT measurements were found to be significantly lower than the two newer instruments.
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Morita T, Shoji N, Kamiya K, Hagishima M, Fujimura F, Shimizu K. Intraocular pressure measured by dynamic contour tonometer and ocular response analyzer in normal tension glaucoma. Graefes Arch Clin Exp Ophthalmol 2009; 248:73-7. [PMID: 19693527 DOI: 10.1007/s00417-009-1169-4] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2009] [Revised: 07/24/2009] [Accepted: 07/27/2009] [Indexed: 11/24/2022] Open
Abstract
BACKGROUND To investigate intraocular pressure (IOP) measurement values in normal tension glaucoma (NTG) eyes using two different types of tonometer that are supposed to be little affected by corneal biochemical properties. METHODS This study included 30 normal eyes of 16 healthy subjects and 30 eyes of 16 patients with NTG. IOP was measured with a Goldmann applanation tonometer (GAT), a Pascal dynamic contour tonometer (DCT), and a Reichert ocular response analyzer (ORA) three times each for normal and NTG eyes. The main measures were GAT-IOP, DCT-IOP, corneal-compensated IOP (IOPcc), Goldmann-correlated IOP (IOPg), and central corneal thickness (CCT). RESULTS In normal eyes, GAT-IOP was 13.2 +/- 1.4 mmHg; DCT-IOP, 13.0 +/- 1.6 mmHg; IOPcc, 13.6 +/- 2.0 mmHg; and IOPg, 12.4 +/- 2.0 mmHg. Multivariate analysis revealed no significant differences between the four measurements (p = 0.08). CCT was 524.6 +/- 27.3 microns. In NTG eyes, GAT-IOP was 13.1 +/- 1.3 mmHg; DCT-IOP, 13.7 +/- 1.3 mmHg; IOPcc, 15.2 +/- 2.0 mmHg; and IOPg, 12.7 +/- 2.0 mmHg. Multivariate analysis showed significant differences between the four measurements (p < 0.01). Sheffé's test showed that IOPcc was significantly higher than GAT-IOP, DCT-IOP, and IOPg (GAT-IOP vs IOPcc: p < 0.0001; DCT-IOP vs IOPcc: p = 0.01; IOPcc vs IOPg: p < 0.0001). CCT was 515.4 +/- 32.9 microns, with no significant difference between normal and NTG eyes (p = 0.15). CONCLUSIONS We investigated the values of IOP in NTG eyes as measured by the DCT and ORA. IOPcc was significantly greater than GAT-IOP, DCT-IOP and IOPg in NTG eyes, suggesting the possibility that IOP values may be underestimated.
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Affiliation(s)
- Tetsuya Morita
- Department of Ophthalmology, Kitasato University School of Medicine, 1-15-1 Kitasato, Sagamihara, Kanagawa 228-8555, Japan.
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Erickson DH, Goodwin D, Rollins M, Belaustegui A, Anderson C. Comparison of dynamic contour tonometry and Goldmann applanation tonometry and their relationship to corneal properties, refractive error, and ocular pulse amplitude. ACTA ACUST UNITED AC 2009; 80:169-74. [PMID: 19329059 DOI: 10.1016/j.optm.2009.01.013] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
Abstract
BACKGROUND Accurate intraocular pressure (IOP) measurement is essential in diagnosing and managing glaucoma. Dynamic contour tonometry (DCT) is less dependent on corneal properties, such as thickness, elasticity, and rigidity, than Goldmann applanation tonometry (GAT). This study examined the relationship between GAT and DCT as well as their relationship with corneal properties and ocular pulse amplitude (OPA). METHODS GAT, DCT, OPA, pachymetry, refractive error, and corneal curvature measurements were obtained on 115 healthy volunteers. RESULTS Participants with thicker corneas (>or=580 microm) had higher IOP measurements with GAT than DCT (P = 0.005). Those with thinner corneas (<or=520 microm) had lower IOP with GAT versus DCT (P = 0.008). GAT and DCT readings did not differ significantly in corneas with average thickness (521 to 579 microm). A clinically significant IOP difference between DCT and GAT was found in 18.2% of subjects. A correlation was found between OPA and both refractive error and IOP (R(2) = .343, P < 0.0001). OPA was higher with increased IOP and decreased myopia. CONCLUSION DCT provides IOP measurements that are less dependent on corneal factors than GAT, aiding in diagnosis and treatment of patients with ocular hypertension and glaucoma. Additional studies are necessary to examine the relationship between OPA, refractive error, and IOP and its possible association with increased incidence of glaucoma in myopic patients.
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Affiliation(s)
- Dina H Erickson
- Pacific University College of Optometry, Forest Grove, Oregon 97116, USA.
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Correlation of intraocular pressure measured with goldmann and dynamic contour tonometry in normal and glaucomatous eyes. J Glaucoma 2009; 18:119-23. [PMID: 19225347 DOI: 10.1097/ijg.0b013e31817d23c7] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
PURPOSE To compare intraocular pressure (IOP) values measured by both Goldmann applanation tonometry (GAT) and dynamic contour tonometry (DCT) in both normal and glaucomatous eyes, and to determine the relationship between these parameters and central corneal thickness (CCT). PATIENTS AND METHODS Forty-seven subjects with primary open-angle glaucoma and 38 normal subjects attended a 12-hour session during which IOP was assessed at 7 time points, every 2 hours, by both GAT and DCT. CCT was also assessed at the same visit. Mean IOP was calculated for each eye of each subject by each method from the 7 diurnal IOP measurements obtained. RESULTS Mean IOP was higher when measured by DCT than by GAT in both normal (by 1.1 mm Hg, P<0.0001) and glaucomatous (by 1.6 mm Hg, P<0.0001) eyes. IOP measurements by GAT and DCT were moderately correlated in both normal (r(2)=0.354, P<0.0001) and glaucomatous (r(2)=0.552, P<0.0001) eyes. In normal eyes, there was a weak positive correlation between GAT IOP and CCT (r(2)=0.088, slope=0.022 mm Hg/microm, P=0.009) and no correlation between DCT IOP and CCT (r(2)=0.007, slope=0.005 mm Hg/microm, P=0.468). In glaucomatous eyes, there was no correlation between GAT IOP and CCT (r(2)=0.006, slope=0.007 mm Hg/microm, P=0.473) and a weak inverse correlation between DCT IOP and CCT (r(2)=0.075, slope=-0.021 mm Hg/microm, P=0.008). CONCLUSIONS Both GAT and DCT are affected by CCT, albeit in different ways. Normal and glaucomatous eyes exhibit different relationships between CCT and IOP measured by either GAT or DCT. The relationships between CCT and transcorneal IOP measurements are complex and incompletely characterized, which limits the clinical interpretation of GAT and DCT measurements of IOP in both normal and glaucomatous eyes.
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Doughty MJ, Gillis N, MacGill J, Montgomery DM. Goldmann tonometry and pachymetry measures in patients with and without topical medical treatment at a glaucoma clinic. Ophthalmic Physiol Opt 2009; 28:558-67. [PMID: 19076558 DOI: 10.1111/j.1475-1313.2008.00596.x] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
PURPOSE To investigate, by audit, the intraocular pressure (IOP) and central corneal thickness (CCT) of patients attending a routine glaucoma clinic, in order to assess the potential effect of CCT on IOP measures. METHODS Data on current IOP (Goldmann), CCT (ultrasound) and glaucoma medications use were collected from 140 patients who presented for a follow-up visit over a 3-month period. Baseline IOP was retrieved from patient records. RESULTS The IOP was lower at follow-up, an expected effect of the use of IOP-lowering medications. However, the CCT was lower in medicated patients indicating, but not proving, that it changed in response to the lowering of IOP. Overall, the measured IOP was higher in patients with greater CCT values (p < 0.001) but this IOP-CCT relationship was most noticeable in patients with normal tension glaucoma and not obvious in those diagnosed with ocular hypertension. Overall, the slope of the IOP-CCT relationship was slightly steeper for those patients prescribed glaucoma medications. CONCLUSIONS In the routine assessment of glaucoma patients, corneal thickness can be shown to have an impact on applanation tonometry data. However, this effect may not be uniformly evident in patients with different types of glaucoma and may be different for patients under topical medical treatment.
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Affiliation(s)
- Michael J Doughty
- Department of Vision Sciences, Glasgow-Caledonian University, Cowcaddens Road, Glasgow G4 OBA, UK.
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Halkiadakis I, Patsea E, Chatzimichali K, Skouriotis S, Chalkidou S, Amariotakis G, Papakonstadinou D, Theodossiadis G, Amariotakis A, Georgopoulos G. Comparison of dynamic contour tonometry with Goldmann applanation tonometry in glaucoma practice. Acta Ophthalmol 2009; 87:323-8. [PMID: 18631335 DOI: 10.1111/j.1755-3768.2008.01239.x] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
PURPOSE To compare intraocular pressure (IOP) readings taken using dynamic contour tonometry (DCT) with IOP readings taken with Goldmann applanation tonometry (GAT) in eyes with glaucoma or ocular hypertension. METHODS The present study included 100 eyes in 100 patients with glaucoma or ocular hypertension. After pachymetry DCT and GAT were performed. Intraocular pressures as measured with DCT and GAT were compared with one another and with central corneal thickness (CCT). RESULTS Mean DCT IOP measurements (20.1 +/- 4.3 mmHg) were significantly (p < 0.001) higher than GAT IOP values (17.9 +/- 4.7 mmHg). The mean difference between DCT and GAT measurements was 2.1 mmHg (range -3.4 to 9.7 mmHg). The difference followed a normal distribution. Measurements made with DCT and GAT correlated significantly with one another (Spearman's rho = 0.761, p < 0.001). Neither GAT nor DCT measurements showed a significant correlation with CCT (537 +/- 39 microm, range 458-656 microm). Multivariate regression analysis has shown that the difference between DCT and GAT is influenced significantly by ocular pulse amplitude (r = -0.334, p = 0.001) and it is not influenced by CCT (r = -0.106, p = 0.292). CONCLUSIONS In eyes with glaucoma or ocular hypertension, DCT facilitates suitable and reliable IOP measurements which are in good concordance with GAT readings. Variation in CCT cannot by itself explain the differences in measurements taken with DCT and GAT in a number of eyes.
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Grieshaber MC, Katamay R, Gugleta K, Kochkorov A, Flammer J, Orgül S. Relationship between ocular pulse amplitude and systemic blood pressure measurements. Acta Ophthalmol 2009; 87:329-34. [PMID: 18937813 DOI: 10.1111/j.1755-3768.2008.01217.x] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
PURPOSE This study aimed to determine whether ocular pulse amplitude (OPA) measured with dynamic contour tonometry (DCT) is related to systemic blood pressure (BP) parameters. METHODS Blood pressure was measured continuously and simultaneously with OPA in one randomly selected eye in 29 healthy subjects. Systemic parameters of interest were: systolic and diastolic BPs and their difference (BP amplitude), and left ventricle ejection time (LVET; defined as the time between the diastolic trough and the incisural notch in the BP curve). In addition, the axial length (AL) of the eye was measured. Associations between OPA, AL and systemic cardiovascular parameters were analysed in a multivariate regression model. RESULTS Measurements of OPA ranged from 1.0 mmHg to 4.9 mmHg (mean 2.3 +/- 0.9 mmHg, median 1.9 mmHg). In a univariate analysis with one predictor at a time, means of intraocular pressure (IOP) (p = 0.008), AL (p = 0.046) and LVET (p = 0.037) were significantly correlated with OPA, whereas systolic and diastolic BPs and their amplitude were not. A multiple linear regression analysis showed that mean IOP (p < 0.005), AL (p = 0.01) and LVET (p = 0.002) all independently contributed to OPA. CONCLUSIONS The OPA readings measured with DCT in healthy subjects were not related to BP levels and amplitude. It seems that the OPA strongly depends on the time-course of the cardiac contraction. Regulating mechanisms in the carotid system as well as scleral rigidity may be responsible for dampening the direct effect of BP variations.
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Comparisons of intraocular pressure measurements: Goldmann applanation tonometry, noncontact tonometry, Tono-Pen tonometry, and dynamic contour tonometry. Eye (Lond) 2009; 23:1582-8. [PMID: 19407845 DOI: 10.1038/eye.2009.77] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022] Open
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Jordão MLS, Pedroso de Carvalho Lupinacci A, Ferreira EL, Enomoto IJF, Costa VP. Influence of age, central corneal thickness, and quality score on dynamic contour tonometry. Eye (Lond) 2008; 23:1364-9. [PMID: 18791544 DOI: 10.1038/eye.2008.278] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022] Open
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Carbonaro F, Andrew T, Mackey DA, Spector TD, Hammond CJ. The Heritability of Corneal Hysteresis and Ocular Pulse Amplitude. Ophthalmology 2008; 115:1545-9. [DOI: 10.1016/j.ophtha.2008.02.011] [Citation(s) in RCA: 44] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2007] [Revised: 02/11/2008] [Accepted: 02/12/2008] [Indexed: 10/22/2022] Open
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Abstract
PURPOSE OF REVIEW In the last 10 years, several new means to measure intraocular pressure have emerged. This review covers recent findings concerning four new technologies: the ocular response analyzer, dynamic contour tonometry, rebound tonometry and the Proview phosphene tonometer. RECENT FINDINGS The ocular response analyzer provides measurements of corneal biomechanics, including corneal hysteresis. Intraocular pressure readings from the ocular response analyzer have correlated well with Goldmann applanation tonometry and seem to be independent of corneal thickness in nonglaucoma patients; however, further studies are needed to determine whether this is true in glaucoma patients. Dynamic contour tonometry also appears to give pressure readings that are independent of corneal thickness. Rebound tonometry is convenient, can be used without topical anesthesia and appears to correlate well with Goldmann tonometry; however, pressure readings from rebound tonometry are not independent of corneal properties. Use of the Proview phosphene tonometer appears to decrease patient anxiety regarding their glaucoma; however, studies have not been supportive of its accuracy. SUMMARY Dynamic contour tonometry provides intraocular pressure readings that are less dependent on corneal properties than Goldmann applanation tonometry. Rebound tonometry appears to correlate well with Goldmann tonometry and can be used without topical anesthesia.
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Comparison of Goldmann applanation tonometry and dynamic contour tonometry in healthy and glaucomatous eyes. Eye (Lond) 2008; 23:262-9. [DOI: 10.1038/sj.eye.6703102] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022] Open
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Pourjavan S, Boëlle PY, Detry-Morel M, De Potter P. Physiological diurnal variability and characteristics of the ocular pulse amplitude (OPA) with the dynamic contour tonometer (DCT-Pascal). Int Ophthalmol 2007; 27:357-60. [PMID: 17955180 DOI: 10.1007/s10792-007-9161-7] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2007] [Accepted: 10/04/2007] [Indexed: 11/25/2022]
Abstract
PURPOSE The Pascal dynamic contour tonometer (DCT) allows measurement of intraocular pressure (IOP) independently of corneal properties. It records, simultaneously, haemodynamic IOP fluctuations and the difference between the systolic and the diastolic IOP corresponding to the ocular pulse amplitude (OPA). The OPA indirectly reflects choroidal perfusion and could be considered as an independent risk factor in glaucoma. We aimed to establish the physiological diurnal variability of the OPA and its correlations with other biophysical parameters because its characteristics remain partly unclear. METHOD Prospective study including 52 eyes of 28 normal subjects with Goldmann applanation tonometry (GAT) IOPs < 22 mmHg. Subjects treated with systemic medications that could interfere with blood pressure or heart rate were excluded. IOP was measured at 9:00 am, 1:00 pm, and 4:00 pm by GAT and DCT. Two consecutive GAT followed by three consecutive DCT measurements were performed in each session by the same clinician (SP). Only DCT measurements with quality 1 and 2 were taken into account. Blood pressure, pulse rate, and central corneal thickness (CCT) were recorded after the last IOP measurements. Spearman correlation coefficient was used for assessment of correlations. RESULTS Mean age was 40 +/- 14 years. Mean DCT values were significantly higher than GAT readings (mean = 16.8 +/- 2.0 vs. 15.2 +/- 2.8 mmHg, P < 0.02). The mean OPA was 2.2 +/- 0.7 mmHg (range: 1-3.4 mmHg). The mean amplitude of diurnal OPA fluctuations was 0.4 mmHg. There was no significant difference in the mean OPA values at each time of the diurnal curve. The intraclass correlation (ICC) of only one OPA measurement in relation to part of total variance due to inter-measurement variation was 78%. Averaging over three independent readings of OPA improved ICC to 91%. The OPA was correlated with GAT (r = 0.31, P < 0.0001) and DCT IOP measurements (r = 0.49, P < 0.0001). It was correlated neither with blood pressure nor with age. OPA values of both eyes of the same individual were highly correlated (r = 0.89, P < 0.0001). CONCLUSION In normal healthy eyes, the ocular pulse amplitude remains stable during normal outpatient office hours and was not correlated with blood pressure or age of patients.
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Affiliation(s)
- Sayeh Pourjavan
- Department of Ophthalmology, St. Luc University Hospital, Universite Catholique De Louvain, Brussels, Belgium.
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