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Liu T, Hung PT, Wang X, Girard MJA. Effect of Eye Globe and Optic Nerve Morphologies on Gaze-Induced Optic Nerve Head Deformations. Invest Ophthalmol Vis Sci 2024; 65:48. [PMID: 39083312 PMCID: PMC11290562 DOI: 10.1167/iovs.65.8.48] [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: 12/20/2023] [Accepted: 06/25/2024] [Indexed: 08/02/2024] Open
Abstract
Purpose The purpose of this study was to investigate the effect of globe and optic nerve (ON) morphologies and tissue stiffnesses on gaze-induced optic nerve head deformations using parametric finite element modeling and a design of experiment (DOE) approach. Methods A custom software was developed to generate finite element models of the eye using 10 morphological parameters: dural radius, scleral, choroidal, retinal, pial and peripapillary border tissue thicknesses, prelaminar tissue depth, lamina cribrosa (LC) depth, ON radius, and ON tortuosity. A central composite face-centered design (1045 models) was used to predict the effects of each morphological factor and their interactions on LC strains induced by 13 degrees of adduction. Subsequently, a further DOE analysis (1045 models) was conducted to study the effects and potential interactions between the top five morphological parameters identified from the initial DOE study and five critical tissue stiffnesses. Results In the DOE analysis of 10 morphological parameters, the 5 most significant factors were ON tortuosity, dural radius, ON radius, scleral thickness, and LC depth. Further DOE analysis incorporating biomechanical parameters highlighted the importance of dural and LC stiffness. A larger dural radius and stiffer dura increased LC strains but the other main factors had the opposite effects. Notably, the significant interactions were found between dural radius with dural stiffness, ON radius, and ON tortuosity. Conclusions This study highlights the significant impact of morphological factors on LC deformations during eye movements, with key morphological effects being more pronounced than tissue stiffnesses.
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Affiliation(s)
- Tingting Liu
- Key Laboratory for Biomechanics and Mechanobiology of Ministry of Education, Beijing Advanced Innovation Center for Biomedical Engineering, School of Biological Science and Medical Engineering, Beihang University, Beijing, China
| | - Pham Tan Hung
- Singapore Eye Research Institute, Singapore National Eye Centre, Singapore
| | - Xiaofei Wang
- Key Laboratory for Biomechanics and Mechanobiology of Ministry of Education, Beijing Advanced Innovation Center for Biomedical Engineering, School of Biological Science and Medical Engineering, Beihang University, Beijing, China
- School of Ophthalmology and Optometry and School of Biomedical Engineering, Wenzhou Medical University, Wenzhou, China
| | - Michaël J. A. Girard
- Singapore Eye Research Institute, Singapore National Eye Centre, Singapore
- Duke-NUS Medical School, Singapore
- Department of Biomedical Engineering, College of Design and Engineering, National University of Singapore, Singapore
- Department of Ophthalmology, Emory University School of Medicine, Atlanta, Georgia, United States
- Department of Biomedical Engineering, Georgia Institute of Technology/Emory University, Atlanta, Georgia, United States
- Emory Empathetic AI for Health Institute, Emory University, Atlanta, Georgia, United States
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Karthikeyan SK, McKendrick AM, Pai VH, Kuzhuppilly NIR, Ganeshrao SB. Contrast Discrimination and Global Form Perception in Primary Open-Angle Glaucoma and Primary Angle-Closure Glaucoma. Invest Ophthalmol Vis Sci 2024; 65:33. [PMID: 38771569 PMCID: PMC11114617 DOI: 10.1167/iovs.65.5.33] [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: 12/15/2023] [Accepted: 05/03/2024] [Indexed: 05/22/2024] Open
Abstract
Purpose This study explored early (contrast discrimination) and intermediate (global form perception) visual processing in primary subtypes of glaucoma: primary open-angle glaucoma (POAG) and primary angle-closure glaucoma (PACG). We aimed to understand early and intermediate visual processing in POAG and PACG, matched for similar visual field defect severity. Methods Early visual processing was measured using a contrast discrimination task described by Porkorny and Smith (1997), and intermediate processing using a global form perception task using glass pattern coherence thresholds. Thresholds were determined centrally and at a single midperipheral location (12.5°) in a quadrant without visual field defects. Controls were tested in corresponding quadrants to individuals with glaucoma. Results Sixty participants (20 POAG, 20 PACG, and 20 age-matched controls), aged 50 to 77 years, were included. Visual field defects were matched between POAG and PACG, with mean deviation values of -6.53 ± 4.46 (range: -1.5 to -16.85) dB and -6.2 ± 4.24 (range: -1.37 to -16.42) dB, respectively. Two-Way ANOVA revealed significant differences in thresholds between the glaucoma groups and the control group for both contrast discrimination and global form perception tasks, with higher thresholds in the glaucoma groups. Post hoc analyses showed no significant contrast discrimination difference between POAG and PACG, but POAG had significantly higher thresholds than PACG for form perception. Conclusions In form perception, POAG showed slightly worse performance than PACG, suggesting that individuals with POAG may experience more severe functional damage than PACG of similar visual field severity.
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Affiliation(s)
- Siddharth K Karthikeyan
- Department of Optometry, Manipal College of Health Professions, Manipal Academy of Higher Education, Manipal, Karnataka, India
| | - Allison M McKendrick
- Department of Optometry and Vision Sciences, The University of Melbourne, Parkville, Australia
- Lions Eye Institute, Nedlands, WA, Australia
- Division of Optometry, School of Allied Health, University of Western Australia, Perth, Australia
| | - Vijaya H Pai
- Department of Ophthalmology, Kasturba Medical College, Manipal, Manipal Academy of Higher Education, Manipal, Karnataka, India
| | - Neetha I R Kuzhuppilly
- Department of Ophthalmology, Kasturba Medical College, Manipal, Manipal Academy of Higher Education, Manipal, Karnataka, India
| | - Shonraj B Ganeshrao
- Department of Optometry, Manipal College of Health Professions, Manipal Academy of Higher Education, Manipal, Karnataka, India
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Xu FY, Lam AK. Intraocular pressure variation from ocular compression in low and high myopia. Clin Exp Optom 2024; 107:213-218. [PMID: 36975202 DOI: 10.1080/08164622.2023.2191784] [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: 11/11/2022] [Accepted: 03/10/2023] [Indexed: 03/29/2023] Open
Abstract
CLINICAL RELEVANCE Change in intraocular pressure during acute ocular compression is related to aqueous humour dynamics. Monitoring intraocular pressure (IOP) change throughout ocular compression has potential to evaluate aqueous outflow facilities. BACKGROUND Recent studies have monitored lamina cribrosa deformation using optical coherence tomography during ocular compression. IOP was measured only once immediately after ocular compression. This study aimed to evaluate IOP changes during and after ocular compression and compare the differences between low and high myopia. METHODS Two groups of young, healthy adults were age-matched and underwent ocular compression. IOP was measured at baseline and monitored during a 2-min ocular compression followed by a 10-min recovery phase. Rebound tonometry was used and applied at 30-s intervals. RESULTS Thirty low and 30 high myopes (60 right eyes) were included in the study. They had similar baseline IOP at 14.9 mmHg. IOP was elevated to 21.7 ± 3.8 mmHg and 22.3 ± 4.2 mmHg for the low and high myopic group, respectively (p = 0.877). Low myopes had faster IOP decay during ocular compression at -3.24 mmHg/min than high myopes at -2.58 mmHg/min (p = 0.0528). The IOP dropped below the baseline level after the release of the compressive force. Low myopes had IOP that returned to baseline levels faster (at 360 s) than high myopes (at 510 s). CONCLUSION Measuring IOP once immediately after ocular compression could under-estimate the effect of IOP elevation during ocular compression. Further studies are required regarding IOP changes from ocular compression in aqueous humour dynamics.
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Affiliation(s)
- Fang-Yu Xu
- School of Optometry, The Hong Kong Polytechnic University, Kowloon, Hong Kong
| | - Andrew Kc Lam
- School of Optometry, The Hong Kong Polytechnic University, Kowloon, Hong Kong
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El Basty A, Gaber R, Elmaria A, Sabry M, Hussein TR. Correlation Between Changes in Lamina Cribrosa Structure and Visual Field in Primary Open-Angle Glaucoma. Clin Ophthalmol 2021; 15:4715-4722. [PMID: 34949912 PMCID: PMC8691195 DOI: 10.2147/opth.s343019] [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: 10/15/2021] [Accepted: 12/07/2021] [Indexed: 11/23/2022] Open
Abstract
Purpose To investigate the correlation between changes in lamina cribrosa (LC) structure using enhanced depth imaging (EDI) and severity of visual field (VF) affection in primary open-angle glaucoma (POAG). Patients and Methods This prospective cross-sectional study was carried out on 52 glaucomatous eyes of 28 POAG patients who attended Tanta University Eye Hospital and 40 normal eyes of 20 age-matched normal subjects from April 2020 to March 2021. POAG patients were classified according to the modified Hodapp-Anderson-Parrish grading scale based on the MD of the standard automated perimetry (SAP) visual field into two groups: group (1) - mild-to-moderate POAG patients (MD ≤ 12 dB), group (2) - severe POAG patients (MD ≥ 12 dB) and the third group included normal (control) age- and gender-matched individuals. Results There was no statistically significant difference between the three groups regarding lamina cribrosa thickness nor lamina cribrosa area and there was no statistically significant correlation between MD and LC thickness, LC area (P-value=0.395 and 0.644). There was a statistically significant correlation between MD and anterior lamina cribrosa surface depth (P-value=0.002) and there was a statistically significant positive correlation between MD and prelaminar neural tissue (PLNT) thickness and prelaminar neural tissue (PLNT) area (P-value= 0.023 and <0.001, respectively). Conclusion EDI-OCT is a useful biomarker of structural changes in ONH and LC, and we recommended it to be a part of the routine monitoring of patients with POAG.
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Affiliation(s)
- Ahmed El Basty
- Department of Ophthalmology, Tanta University, Tanta, Gharbeya Province, Egypt
| | - Raouf Gaber
- Department of Ophthalmology, Tanta University, Tanta, Gharbeya Province, Egypt
| | - Ahmed Elmaria
- Department of Ophthalmology, Tanta University, Tanta, Gharbeya Province, Egypt
| | - Moataz Sabry
- Department of Ophthalmology, Tanta University, Tanta, Gharbeya Province, Egypt
| | - Tarek R Hussein
- Department of Ophthalmology, Tanta University, Tanta, Gharbeya Province, Egypt
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Kim J, Gardiner SK, Ramazzotti A, Karuppanan U, Bruno L, Girkin CA, Downs JC, Fazio MA. Strain by virtual extensometers and video-imaging optical coherence tomography as a repeatable metric for IOP-Induced optic nerve head deformations. Exp Eye Res 2021; 211:108724. [PMID: 34375590 PMCID: PMC8511063 DOI: 10.1016/j.exer.2021.108724] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2020] [Revised: 07/27/2021] [Accepted: 08/06/2021] [Indexed: 11/20/2022]
Abstract
PURPOSE To determine if in vivo strain response of the Optic Nerve Head (ONH) to IOP elevation visualized using Optical Coherence Tomography (OCT) video imaging and quantified using novel virtual extensometers was able to be provided repeatable measurements of tissue specific deformations. METHODS The ONHs of 5 eyes from 5 non-human primates (NHPs) were imaged by Spectralis OCT. A vertical and a horizontal B-scan of the ONH were continuously recorded for 60 s at 6 Hz (video imaging mode) during IOP elevation from 10 to 30 mmHg. Imaging was repeated over three imaging sessions. The 2D normal strain was computed by template-matching digital image correlation using virtual extensometers. ANOVA F-test (F) was used to compare inter-eye, inter-session, and inter-tissue variability for the prelaminar, Bruch's membrane opening (BMO), lamina cribrosa (LC) and choroidal regions (against variance the error term). F-test of the ratio between inter-eye to inter-session variability was used to test for strain repeatability across imaging sessions (FIS). RESULTS Variability of strain across imaging session (F = 0.7263, p = 0.4855) and scan orientation was not significant (F = 1.053, p = 0.3066). Inter session variability of strain was significantly lower than inter-eye variability (FIS = 22.63, p = 0.0428) and inter-tissue variability (FIS = 99.33 p = 0.00998). After IOP elevation, strain was highest in the choroid (-18.11%, p < 0.001), followed by prelaminar tissue (-11.0%, p < 0.001), LC (-3.79%, p < 0.001), and relative change in BMO diameter (-0.57%, p = 0.704). CONCLUSIONS Virtual extensometers applied to video-OCT were sensitive to the eye-specific and tissue-specific mechanical response of the ONH to IOP and were repeatable across imaging sessions.
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Affiliation(s)
- Jihee Kim
- Biomedical Engineering, University of Alabama at Birmingham, Birmingham, AL, USA
| | | | - Andrea Ramazzotti
- Ophthalmology and Visual Sciences, University of Alabama at Birmingham, Birmingham, AL, USA
| | - Udayakumar Karuppanan
- Ophthalmology and Visual Sciences, University of Alabama at Birmingham, Birmingham, AL, USA
| | - Luigi Bruno
- Department of Mechanical, Energy and Management Engineering, University of Calabria, Rende, CS, Italy
| | - Christopher A Girkin
- Ophthalmology and Visual Sciences, University of Alabama at Birmingham, Birmingham, AL, USA
| | - J Crawford Downs
- Ophthalmology and Visual Sciences, University of Alabama at Birmingham, Birmingham, AL, USA
| | - Massimo A Fazio
- Biomedical Engineering, University of Alabama at Birmingham, Birmingham, AL, USA; Ophthalmology and Visual Sciences, University of Alabama at Birmingham, Birmingham, AL, USA; The Viterbi Family Department of Ophthalmology, UC San Diego, La Jolla, CA, USA.
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Abstract
SIGNIFICANCE Scleral lenses (SLs) are increasing in scope, and understanding their ocular health impact is imperative. The unique fit of an SL raises concern that the landing zone causes compression of conjunctival tissue that can lead to resistance of aqueous humor outflow and increased intraocular pressure (IOP). PURPOSE This study aimed to assess changes in optic nerve head morphology as an indirect assessment of IOP and evaluate other IOP assessment methods during SL wear. METHODS Twenty-six healthy adults wore SL on one randomly selected eye for 6 hours, whereas the fellow eye served as a control. Global minimum rim width (optical coherence tomography) and IOP (Icare, Diaton) were measured at baseline, 2 and 6 hours after SL application, and again after SL removal. Central corneal thickness, anterior chamber depth, and fluid reservoir depth were monitored. RESULTS Minimum rim width thinning was observed in the test (-8 μm; 95% confidence interval [CI], -11 to -6 μm) and control (-6 μm; 95% CI, -9 to -3 μm) eyes after 6 hours of SL wear (P < .01), although the magnitude of thinning was not significantly greater in the lens-wearing eyes (P = .09). Mean IOP (Icare) significantly increased +2 mmHg (95% CI, +1 to +3 mmHg) in the test eyes (P = .002), with no change in the control eyes. Mean IOP changes with Diaton were +0.3 mmHg (95% CI, -0.9 to +3.2 mmHg) in the test eyes and +0.4 mmHg (95% CI, -0.8 to +1.7 mmHg) in the control eyes. However, Diaton tonometry showed poor within-subject variation and poor correlation with Icare. No clinically significant changes were observed in central corneal thickness or anterior chamber depth. CONCLUSIONS This study suggests that SLs have a minimal effect on IOP homeostasis in the normal eye during SL wear and an insignificant impact on the optic nerve head morphology in healthy adult eyes.
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Fortune B. Optical coherence tomography evaluation of the optic nerve head neuro‐retinal rim in glaucoma. Clin Exp Optom 2021; 102:286-290. [DOI: 10.1111/cxo.12833] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2018] [Accepted: 08/09/2018] [Indexed: 12/30/2022] Open
Affiliation(s)
- Brad Fortune
- Discoveries in Sight Research Laboratories, Devers Eye Institute, Legacy Health, Portland, Oregon, USA,
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Elucidation of the role of the lamina cribrosa in glaucoma using optical coherence tomography. Surv Ophthalmol 2021; 67:197-216. [PMID: 33548238 DOI: 10.1016/j.survophthal.2021.01.015] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2020] [Revised: 01/24/2021] [Accepted: 01/25/2021] [Indexed: 01/07/2023]
Abstract
Glaucoma is a chronic and progressive optic neuropathy characterized by the death of retinal ganglion cells and corresponding visual field loss. Despite the growing number of studies on the subject, the pathogenesis of the disease remains unclear. Notwithstanding, several studies have shown that the lamina cribrosa (LC) is considered an anatomic site of glaucomatous optic nerve injury, thus having a key role in the pathophysiology of glaucoma development and progression. Different morphological alterations of the LC have been described in vivo in glaucomatous eyes after the evolution of optical coherence tomography (OCT) devices. The most relevant findings were the reduction of laminar thickness, the presence of localized defects, and the posterior LC displacement. These new laminar parameters documented through OCT are not only promising as possible additional tools for glaucoma diagnosis and monitoring, but also as predictors of disease progression. In spite of the advance of technology, however, proper evaluation of the LC is not yet viable in all eyes. We describe OCT-identified LC changes related to the development and progression of glaucoma and provide future directions based on a critical data analysis, focusing on its clinical relevance and applicability.
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A comparative study on the effects of flexible and rigid laryngoscopy techniques on intraocular pressure. Eur Arch Otorhinolaryngol 2020; 278:167-171. [PMID: 32749604 DOI: 10.1007/s00405-020-06263-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2020] [Accepted: 07/30/2020] [Indexed: 10/23/2022]
Abstract
OBJECTIVES This study compared the impact of transoral rigid laryngoscopy (TORL) and transnasal flexible laryngoscopy (TNFL) methods on intraocular pressure (IOP). METHODS This study included 100 patients, with 50 patients undergoing a TORL, and 50 patients a TNFL. Before procedure IOP values were recorded by an ophthalmologist using Icare Pro tonometry, also immediately post procedure, and at the 15th, 30th and 60th minute after laryngoscopy. RESULTS Both groups were similar in terms of age, gender, mean body mass index (BMI), and pre-laryngoscopy IOP values. When the TNFL and TORL groups were compared, no significant differences were observed between pre-laryngoscopy, and 60th minute IOP values (p = 0.891, p = 0.149, respectively). IOP values measured immediately after laryngoscopy, and at the 15th and 30th minute were significantly higher in the TORL group (p < 0.001, p < 0.001, p = 0.002, respectively). CONCLUSIONS We demonstrated higher IOP fluctuations in the TORL group, when compared to the TNFL group. For this reason, TNFL may be considered a safer method for evaluating laryngeal tissues in conditions that require lower IOP fluctuation as in glaucoma. However, further studies are required to clarify the exact effects of IOP fluctuations during TNFL and TORL in patients with glaucoma.
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Chen W, Hu T, Xu Q, Chen Z, Zhang H, Wang J. Acute Effects of Intraocular Pressure-Induced Changes in Schlemm's Canal Morphology on Outflow Facility in Healthy Human Eyes. Invest Ophthalmol Vis Sci 2020; 61:36. [PMID: 32716504 PMCID: PMC7425758 DOI: 10.1167/iovs.61.8.36] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Abstract
Purpose To estimate the outflow facility coefficient (C) as a function of Schlemm's canal cross-sectional area (SCAR) in healthy subjects using noninvasive oculopression tonometry (OPT). Methods In 25 healthy volunteers, intraocular pressure (IOP) decay values were recorded by a ophthalmodynamometer, with a fixed external force (0.15 N) on the inferior-temporal eyelid, every 10 seconds, for four minutes, and again after a 30-minute rest. Schlemm's canal profile images and IOP were obtained pre-procedurally (baseline), immediately (T0), and at 1-minute intervals post-procedurally (T1, T2, T3, and T4). C was calculated for different IOPs. The SCAR, coronal, and the meridional diameter of Schlemm's canal were calculated. Results Mean C0 for the maximum IOP was 0.020 ± 0.017 µL/min/mm Hg; mean C was 0.018 ± 0.0071 and 0.058 ± 0.0146 µL/min/mm Hg at 40 and 20 mm Hg, respectively. C was nonlinearly dependent on the IOP (R2 = 0.945). The SCAR was 5440 ± 3140.82, 3947.6 ± 2246.8, and 5375.7 ± 2662.7 µm2 at baseline, T0, and T4, respectively. The coronal diameter of SC decreased significantly from the baseline (33.02 ± 11.3 µm) to T0 (26.6 ± 9.37 µm) and recovered at T4 (32.3 ± 9.53 µm). The SCAR and IOP correlated significantly throughout (R2 = 0.9944; P < 0.001). C0 significantly correlated with the SCAR at baseline and with changes in the SCAR and IOP from T0 to T4. Conclusions Schlemm's canal dimensions are responsible for the IOP-dependent mechanical forces, and these changes appear to directly affect outflow facility.
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Tun TA, Wang X, Baskaran M, Nongpiur ME, Tham YC, Nguyen DQ, Strouthidis NG, Aung T, Cheng CY, Boote C, Girard MJA. Determinants of lamina cribrosa depth in healthy Asian eyes: the Singapore Epidemiology Eye Study. Br J Ophthalmol 2020; 105:367-373. [PMID: 32434775 DOI: 10.1136/bjophthalmol-2020-315840] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2020] [Revised: 04/24/2020] [Accepted: 04/29/2020] [Indexed: 11/04/2022]
Abstract
AIM To investigate the determinants of lamina cribrosa depth (LCD) in healthy eyes of Chinese and Indian Singaporean adults. METHODS The optic nerve head (ONH) of the right eye of 1396 subjects (628 Chinese and 768 Indian subjects) was imaged with optical coherence tomography (OCT, Spectralis, Heidelberg, Germany). LCD was defined as the distance from the Bruch's membrane opening (LCD-BMO) or the peripapillary sclera (LCD-PPS) reference plane to the laminar surface. A linear regression model was used to evaluate the relationship between the LCD and its determinants. RESULTS Both LCDs were significantly different between the two races (LCD-BMO: 421.95 (95% CI 365.32 to 491.79) µm in Chinese vs 430.39 (367.46-509.81) µm in Indians, p=0.021; and LCD-PPS: 353.34 (300.98-421.45) µm in Chinese vs 376.76 (313.39-459.78) µm in Indians, p<0.001). In the multivariable regression analysis, the LCD-PPS of the whole cohort was independently associated with females (β=-31.93, p<0.001), Indians subjects (β=21.39, p=0.004) (Chinese as the reference), axial length (Axl) (β=-6.68, p=0.032), retinal nerve fibre layer thickness (RNFL) (β=0.71, p=0.019), choroidal thickness (ChT) (β=0.41, p<0.001), vertical cup disc ratio (VCDR) (β=24.42, p<0.001) and disc size (β=-60.75, p=0.001). For every 1 year older in age, the LCD-PPS was deeper on average by 1.95 µm in Chinese subjects (p=0.01) but there was no association in Indians subjects (p=0.851). CONCLUSIONS The LCD was influenced by age, gender, race, Axl, RNFL, ChT, VCDR and disc size. This normative LCD database may facilitate a more accurate assessment of ONH cupping using OCT in Asian populations.
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Affiliation(s)
- Tin A Tun
- Glaucoma, Singapore Eye Research Institute, Singapore.,Department of Biomedical Engineering, National University of Singapore, Singapore
| | - Xiaofei Wang
- Department of Biomedical Engineering, National University of Singapore, Singapore.,Biological Science and Medical Engineering, Beihang University, Beijing, China
| | - Mani Baskaran
- Glaucoma, Singapore Eye Research Institute, Singapore
| | - Monisha Esther Nongpiur
- Glaucoma, Singapore Eye Research Institute, Singapore.,Department of Ophthalmology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore
| | - Yih Chung Tham
- Ocular Epidemiology Research Group and Data Science, Singapore Eye Research Institute, Singapore
| | - Duc Quang Nguyen
- Ocular Epidemiology Research Group and Data Science, Singapore Eye Research Institute, Singapore
| | - Nicholas G Strouthidis
- NIHR Biomedical Research Centre, Moorfields Eye Hospital NHS Foundation Trust and UCL Institute of Ophthalmology, London, UK
| | - Tin Aung
- Glaucoma, Singapore Eye Research Institute, Singapore.,Department of Ophthalmology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore
| | - Ching-Yu Cheng
- Department of Ophthalmology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore.,Ocular Epidemiology Research Group and Data Science, Singapore Eye Research Institute, Singapore
| | - Craig Boote
- Optometry and Vision Sciences, Cardiff University, Cardiff, UK
| | - Michael J A Girard
- Department of Biomedical Engineering, National University of Singapore, Singapore
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12
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Scott JM, Tucker WJ, Haykowsky MJ. Lamina Cribrosa Pore Diameter and Spaceflight-Associated Neuro-ocular Syndrome—Reply. JAMA Ophthalmol 2019; 137:1331. [DOI: 10.1001/jamaophthalmol.2019.3322] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022]
Affiliation(s)
| | - Wesley J. Tucker
- Integrated Cardiovascular Exercise Physiology and Rehabilitation Laboratory, College of Nursing and Health Innovation, University of Texas at Arlington, Arlington
| | - Mark J. Haykowsky
- Integrated Cardiovascular Exercise Physiology and Rehabilitation Laboratory, College of Nursing and Health Innovation, University of Texas at Arlington, Arlington
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13
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Tun TA, Wang X, Baskaran M, Nongpiur ME, Tham YC, Perera SA, Strouthidis NG, Aung T, Cheng CY, Girard MJA. Variation of Peripapillary Scleral Shape With Age. Invest Ophthalmol Vis Sci 2019; 60:3275-3282. [PMID: 31369672 PMCID: PMC6675518 DOI: 10.1167/iovs.19-26777] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2019] [Accepted: 06/18/2019] [Indexed: 11/24/2022] Open
Abstract
Purpose To define the shape of the anterior surface of the peripapillary sclera (PPS) and evaluate its relationship with age and ocular determinants in a population-based Chinese cohort. Methods The optic nerve heads of 619 healthy Chinese subjects were imaged with spectral-domain optical coherence tomography. To assess the shape of the PPS/Bruch's membrane (BM), we measured the angle between a line parallel to the nasal anterior PPS/BM boundary and one parallel to the temporal side. A negative value indicated that the PPS/BM followed an inverted v-shaped configuration (peak pointing toward the vitreous), whereas a positive value indicated that it followed a v-shaped configuration (peak pointing toward the orbital tissues). A linear regression model was used to evaluate the relationship between the PPS angle and other ocular parameters. Results The mean PPS angle was 3.68° ± 6.73° and the BM angle was 9.69° ± 5.05°. The PPS angle increased on average by 0.233 deg/y. A v-shaped PPS was significantly associated with age (β = 0.087, P = 0.004), peripapillary choroidal thickness (β = -0.479, P < 0.001), lamina cribrosa depth (β = 0.307, P < 0.001), and BM angle (β = 0.487, P < 0.001) after adjusting for best corrected visual acuity, central corneal thickness, and axial length. Conclusions The anterior surface of PPS of an elderly adult population had a v-shaped configuration and was more pronounced with increasing age, thin peripapillary choroid, and a deep cup. Such a change in shape with age could have an impact on the biomechanical environment of the optic nerve head.
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Affiliation(s)
- Tin A. Tun
- Singapore Eye Research Institute and Singapore National Eye Centre, Singapore
- Ophthalmic Engineering & Innovation Laboratory, Department of Biomedical Engineering, National University of Singapore, Singapore
| | - Xiaofei Wang
- Ophthalmic Engineering & Innovation Laboratory, Department of Biomedical Engineering, National University of Singapore, Singapore
- Beijing Advanced Innovation Center for Biomedical Engineering, School of Biological Science and Medical Engineering, Beihang University, Beijing, China
| | - Mani Baskaran
- Singapore Eye Research Institute and Singapore National Eye Centre, Singapore
- Duke-NUS Medical School, Singapore
| | - Monisha E. Nongpiur
- Singapore Eye Research Institute and Singapore National Eye Centre, Singapore
- Duke-NUS Medical School, Singapore
| | - Yih-Chung Tham
- Singapore Eye Research Institute and Singapore National Eye Centre, Singapore
| | - Shamira A. Perera
- Singapore Eye Research Institute and Singapore National Eye Centre, Singapore
- Duke-NUS Medical School, Singapore
| | - Nicholas G. Strouthidis
- Singapore Eye Research Institute and Singapore National Eye Centre, Singapore
- NIHR Biomedical Research Centre, Moorfields Eye Hospital NHS Foundation Trust and UCL Institute of Ophthalmology, London, United Kingdom
- Discipline of Clinical Ophthalmology and Eye Health, University of Sydney, Sydney, New South Wales, Australia
| | - Tin Aung
- Singapore Eye Research Institute and Singapore National Eye Centre, Singapore
- Duke-NUS Medical School, Singapore
- Department of Ophthalmology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore
| | - Ching-Yu Cheng
- Singapore Eye Research Institute and Singapore National Eye Centre, Singapore
- Duke-NUS Medical School, Singapore
- Department of Ophthalmology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore
| | - Michaël J. A. Girard
- Singapore Eye Research Institute and Singapore National Eye Centre, Singapore
- Ophthalmic Engineering & Innovation Laboratory, Department of Biomedical Engineering, National University of Singapore, Singapore
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14
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Lopes FS, Matsubara I, Almeida I, Dorairaj SK, Vessani RM, Paranhos A, Prata TS. Structure-function relationships in glaucoma using enhanced depth imaging optical coherence tomography-derived parameters: a cross-sectional observational study. BMC Ophthalmol 2019; 19:52. [PMID: 30770751 PMCID: PMC6377769 DOI: 10.1186/s12886-019-1054-9] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2018] [Accepted: 01/29/2019] [Indexed: 12/14/2022] Open
Abstract
Background To investigate structural and functional correlations in glaucoma patients using enhanced depth imaging spectral-domain optical coherence tomography (EDI OCT)-derived parameters. Methods We prospectively enrolled healthy participants and glaucomatous patients with a wide range of disease stages. All participants underwent visual field (VF) testing (SITA - Standard 24–2; Carl Zeiss Meditec, Dublin, CA) and EDI OCT imaging (Spectralis; Heidelberg Engineering Co., Heidelberg, Germany). The following optic nerve head parameters were measured on serial vertical EDI OCT B-scans by two experienced examiners masked to patients clinical data: lamina cribrosa (LC) thickness and area, prelaminar neural tissue thickness and area, anterior LC depth, Bruch’s membrane opening (BMO) and average, superior, and inferior BMO-minimum rim width (BMO-MRW). Only good quality images were considered, and whenever both eyes were eligible, one was randomly selected for analysis. Scatter plots were constructed to investigate correlations between each anatomic parameter and patient’s VF status (based on VF index [VFI] values). Results A total of 73 eyes of 73 patients were included. All EDI OCT parameters evaluated differed significantly between glaucomatous and control eyes (P ≤ 0.045). A secondary analysis, in which glaucomatous patients were divided according to VF mean deviation index values into 3 groups (mild [G1; > − 6 dB], moderate [G2; − 6 to − 12 dB] and advanced [G3; <− 12 dB] glaucoma), revealed that average BMO-MRW was the EDI OCT parameter that presented more significant differences between the different stages of glaucoma. Significant structure-function correlations were found between VFI values and prelaminar neural tissue area (R2 = 0.20, P = 0.017), average BMO-MRW (R2 = 0.35, P ≤ 0.001), superior BMO-MRW (R2 = 0.21, P = 0.012), and inferior BMO-MRW (R2 = 0.27, P = 0.002). No significant correlations were found for LC area and anterior LC depth (P ≥ 0.452). Conclusions Evaluating the distribution pattern and structure-function correlations of different laminar and prelaminar EDI OCT-derived parameters in glaucomatous patients, we found better results for neural tissue-based indexes (compared to LC-derived parameters). The diagnostic utility of each parameter deserves further investigations. Electronic supplementary material The online version of this article (10.1186/s12886-019-1054-9) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Flavio S Lopes
- Glaucoma Service, Department of Ophthalmology, Federal University of São Paulo, Rua Botucatu, 821, Vila Clementino, São Paulo, 04021-001, Brazil.,Glaucoma Unit, Hospital Medicina dos Olhos, R. Salém Bechara, 281, Centro, Osasco, 06018-180, Brazil
| | - Igor Matsubara
- Glaucoma Service, Department of Ophthalmology, Federal University of São Paulo, Rua Botucatu, 821, Vila Clementino, São Paulo, 04021-001, Brazil.,Glaucoma Unit, Hospital Medicina dos Olhos, R. Salém Bechara, 281, Centro, Osasco, 06018-180, Brazil
| | - Izabela Almeida
- Glaucoma Service, Department of Ophthalmology, Federal University of São Paulo, Rua Botucatu, 821, Vila Clementino, São Paulo, 04021-001, Brazil.,Glaucoma Unit, Hospital Medicina dos Olhos, R. Salém Bechara, 281, Centro, Osasco, 06018-180, Brazil
| | - Syril K Dorairaj
- Department of Ophthalmology, Mayo Clinic, 4500 San Pablo Rd, Jacksonville, FL, 32224, USA.
| | - Roberto M Vessani
- Glaucoma Service, Department of Ophthalmology, Federal University of São Paulo, Rua Botucatu, 821, Vila Clementino, São Paulo, 04021-001, Brazil
| | - Augusto Paranhos
- Glaucoma Service, Department of Ophthalmology, Federal University of São Paulo, Rua Botucatu, 821, Vila Clementino, São Paulo, 04021-001, Brazil
| | - Tiago S Prata
- Glaucoma Service, Department of Ophthalmology, Federal University of São Paulo, Rua Botucatu, 821, Vila Clementino, São Paulo, 04021-001, Brazil.,Glaucoma Unit, Hospital Medicina dos Olhos, R. Salém Bechara, 281, Centro, Osasco, 06018-180, Brazil.,Department of Ophthalmology, Mayo Clinic, 4500 San Pablo Rd, Jacksonville, FL, 32224, USA
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15
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Martin KR, Mansouri K, Weinreb RN, Wasilewicz R, Gisler C, Hennebert J, Genoud D. Use of Machine Learning on Contact Lens Sensor-Derived Parameters for the Diagnosis of Primary Open-angle Glaucoma. Am J Ophthalmol 2018; 194:46-53. [PMID: 30053471 DOI: 10.1016/j.ajo.2018.07.005] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2018] [Revised: 07/10/2018] [Accepted: 07/11/2018] [Indexed: 01/28/2023]
Abstract
PURPOSE To test the hypothesis that contact lens sensor (CLS)-based 24-hour profiles of ocular volume changes contain information complementary to intraocular pressure (IOP) to discriminate between primary open-angle glaucoma (POAG) and healthy (H) eyes. DESIGN Development and evaluation of a diagnostic test with machine learning. METHODS Subjects: From 435 subjects (193 healthy and 242 POAG), 136 POAG and 136 age-matched healthy subjects were selected. Subjects with contraindications for CLS wear were excluded. PROCEDURE This is a pooled analysis of data from 24 prospective clinical studies and a registry. All subjects underwent 24-hour CLS recording on 1 eye. Statistical and physiological CLS parameters were derived from the signal recorded. CLS parameters frequently associated with the presence of POAG were identified using a random forest modeling approach. MAIN OUTCOME MEASURES Area under the receiver operating characteristic curve (ROC AUC) for feature sets including CLS parameters and Start IOP, as well as a feature set with CLS parameters and Start IOP combined. RESULTS The CLS parameters feature set discriminated POAG from H eyes with mean ROC AUCs of 0.611, confidence interval (CI) 0.493-0.722. Larger values of a given CLS parameter were in general associated with a diagnosis of POAG. The Start IOP feature set discriminated between POAG and H eyes with a mean ROC AUC of 0.681, CI 0.603-0.765. The combined feature set was the best indicator of POAG with an ROC AUC of 0.759, CI 0.654-0.855. This ROC AUC was statistically higher than for CLS parameters or Start IOP feature sets alone (both P < .0001). CONCLUSIONS CLS recordings contain information complementary to IOP that enable discrimination between H and POAG. The feature set combining CLS parameters and Start IOP provide a better indication of the presence of POAG than each of the feature sets separately. As such, the CLS may be a new biomarker for POAG.
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Affiliation(s)
- Keith R Martin
- Department of Ophthalmology, Cambridge University Hospitals NHS Foundation Trust, Cambridge, United Kingdom.
| | - Kaweh Mansouri
- Shiley Eye Institute, Hamilton Glaucoma Center and Department of Ophthalmology, University of California San Diego, La Jolla, California, USA
| | - Robert N Weinreb
- Shiley Eye Institute, Hamilton Glaucoma Center and Department of Ophthalmology, University of California San Diego, La Jolla, California, USA
| | - Robert Wasilewicz
- Przemienienia Pańskiego Hospital, Department of Ophthalmology, Division of Ophthalmology, Poznan University of Medical Sciences Karol Marcinkowski, Poznań, Poland
| | - Christophe Gisler
- University of Applied Sciences Western Switzerland (HES-SO) Fribourg, Fribourg, Switzerland
| | - Jean Hennebert
- University of Applied Sciences Western Switzerland (HES-SO) Valais, Institute of Information Systems, Sierre, Switzerland
| | - Dominique Genoud
- University of Applied Sciences Western Switzerland (HES-SO) Valais, Institute of Information Systems, Sierre, Switzerland
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16
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Devalla SK, Renukanand PK, Sreedhar BK, Subramanian G, Zhang L, Perera S, Mari JM, Chin KS, Tun TA, Strouthidis NG, Aung T, Thiéry AH, Girard MJA. DRUNET: a dilated-residual U-Net deep learning network to segment optic nerve head tissues in optical coherence tomography images. BIOMEDICAL OPTICS EXPRESS 2018; 9:3244-3265. [PMID: 29984096 PMCID: PMC6033560 DOI: 10.1364/boe.9.003244] [Citation(s) in RCA: 90] [Impact Index Per Article: 15.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/29/2018] [Revised: 06/06/2018] [Accepted: 06/11/2018] [Indexed: 05/18/2023]
Abstract
Given that the neural and connective tissues of the optic nerve head (ONH) exhibit complex morphological changes with the development and progression of glaucoma, their simultaneous isolation from optical coherence tomography (OCT) images may be of great interest for the clinical diagnosis and management of this pathology. A deep learning algorithm (custom U-NET) was designed and trained to segment 6 ONH tissue layers by capturing both the local (tissue texture) and contextual information (spatial arrangement of tissues). The overall Dice coefficient (mean of all tissues) was 0.91 ± 0.05 when assessed against manual segmentations performed by an expert observer. Further, we automatically extracted six clinically relevant neural and connective tissue structural parameters from the segmented tissues. We offer here a robust segmentation framework that could also be extended to the 3D segmentation of the ONH tissues.
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Affiliation(s)
- Sripad Krishna Devalla
- Ophthalmic Engineering & Innovation Laboratory, Department of Biomedical Engineering, Faculty of Engineering, National University of Singapore, Singapore
| | - Prajwal K Renukanand
- Ophthalmic Engineering & Innovation Laboratory, Department of Biomedical Engineering, Faculty of Engineering, National University of Singapore, Singapore
| | - Bharathwaj K Sreedhar
- Ophthalmic Engineering & Innovation Laboratory, Department of Biomedical Engineering, Faculty of Engineering, National University of Singapore, Singapore
| | - Giridhar Subramanian
- Ophthalmic Engineering & Innovation Laboratory, Department of Biomedical Engineering, Faculty of Engineering, National University of Singapore, Singapore
| | - Liang Zhang
- Ophthalmic Engineering & Innovation Laboratory, Department of Biomedical Engineering, Faculty of Engineering, National University of Singapore, Singapore
| | - Shamira Perera
- Duke-NUS, Graduate Medical School, Singapore
- Singapore Eye Research Institute, Singapore National Eye Centre, Singapore
| | - Jean-Martial Mari
- GePaSud, Université de la Polynésie française, Tahiti, French Polynesia
| | - Khai Sing Chin
- Department of Statistics and Applied Probability, National University of Singapore, Singapore
| | - Tin A Tun
- Ophthalmic Engineering & Innovation Laboratory, Department of Biomedical Engineering, Faculty of Engineering, National University of Singapore, Singapore
- Singapore Eye Research Institute, Singapore National Eye Centre, Singapore
| | - Nicholas G Strouthidis
- Singapore Eye Research Institute, Singapore National Eye Centre, Singapore
- NIHR Biomedical Research Centre at Moorfields Eye Hospital NHS Foundation Trust and UCL Institute of Ophthalmology, London, UK
- Discipline of Clinical Ophthalmology and Eye Health, University of Sydney, Sydney, New South Wales, Australia
| | - Tin Aung
- Singapore Eye Research Institute, Singapore National Eye Centre, Singapore
| | - Alexandre H Thiéry
- Department of Statistics and Applied Probability, National University of Singapore, Singapore
| | - Michaël J A Girard
- Ophthalmic Engineering & Innovation Laboratory, Department of Biomedical Engineering, Faculty of Engineering, National University of Singapore, Singapore
- Singapore Eye Research Institute, Singapore National Eye Centre, Singapore
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17
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Bedggood P, Tanabe F, McKendrick AM, Turpin A, Anderson AJ, Bui BV. Optic nerve tissue displacement during mild intraocular pressure elevation: its relationship to central corneal thickness and corneal hysteresis. Ophthalmic Physiol Opt 2018; 38:389-399. [DOI: 10.1111/opo.12568] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2018] [Accepted: 05/08/2018] [Indexed: 01/29/2023]
Affiliation(s)
- Phillip Bedggood
- Department of Optometry and Vision Sciences The University of Melbourne Parkville Australia
| | - Fumi Tanabe
- Faculty of Medicine Department of Ophthalmology Kindai University Osaka‐Sayama Japan
| | - Allison M. McKendrick
- Department of Optometry and Vision Sciences The University of Melbourne Parkville Australia
| | - Andrew Turpin
- School of Computing and Information Systems The University of Melbourne Parkville Australia
| | - Andrew J. Anderson
- Department of Optometry and Vision Sciences The University of Melbourne Parkville Australia
| | - Bang V. Bui
- Department of Optometry and Vision Sciences The University of Melbourne Parkville Australia
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18
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ZAREEI A, RAZEGHINEJAD MR, SALOUTI R. Corneal Biomechanical Properties and Thickness in Primary Congenital Glaucoma and Normal Eyes: A Comparative Study. MEDICAL HYPOTHESIS, DISCOVERY & INNOVATION OPHTHALMOLOGY JOURNAL 2018; 7:68-72. [PMID: 30250855 PMCID: PMC6146241] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The correct estimation of Intraocular Pressure (IOP) is the most important factor in the management of various types of glaucoma. Primary congenital glaucoma is a type of glaucoma that can cause blindness in the absence of control of the IOP. In this retrospective observational study, 95 eyes, including 48 healthy eyes and 47 eyes with Primary Congenital Glaucomatous (PCG) were studied. Two groups were matched for age, gender, and Goldman Applanation Tonometry (GIOP). Corneal Hysteresis (CH), Corneal Resistance Factor (CRF), and Goldman intraocular pressure were measured by ORA (IOPg), and corneal compensated Intraocular Pressure (IOPcc) was measured for each patient using the Ocular Response Analyzer (ORA). Central Corneal Thickness (CCT) was measured by ultrasonic pachymetry. For each patient, one eye was selected randomly. Student's t-test and analytical regression were used for statistical analysis. The two groups were matched for age (P = 0.34), gender (P = 0.47), and GIOP (P = 0.17). Corneal hysteresis and CRF were significantly lower in PCG than in normal eyes (P < 0.0001), yet CCT was significantly thicker in PCG than normal eyes (P < 0.0001). The regression equation on the effect of CH, CRF, and CCT on GIOP in the PCG group showed that CH and CRF (P-value = 0.001 and P-value<0.0001) also had a significant effect yet CCT did not (P-value = 0.691). A significant decrease in CH and CRF was found in the PCG group compared to the normal controls. In the PCG group, the CCT was greater than normal. These results showed the usefulness of biomechanical properties (CH, CRF) in order to interpret IOP measurements. Furthermore, GIOP measurement may not be confined to consideration of CCT alone. A low CH and CRF value could be responsible for under-estimation of GIOP in the PCG group, in comparison to the normal controls.
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Affiliation(s)
- Athar ZAREEI
- Poostchi Ophthalmology Research Center, Department of Ophthalmology, Shiraz University of Medical Sciences, Shiraz, Iran,Correspondence to: Athar Zareei, MSc, Poostchi Ophthalmology Research Center, Shiraz University of Medical Sciences, Zand Street, Shiraz, Iran. E-mail:
| | - Mohammad Reza RAZEGHINEJAD
- Poostchi Ophthalmology Research Center, Department of Ophthalmology, Shiraz University of Medical Sciences, Shiraz, Iran,Glaucoma Service, Wills Eye Hospital, Philadelphia, PA, United States
| | - Ramin SALOUTI
- Poostchi Ophthalmology Research Center, Department of Ophthalmology, Shiraz University of Medical Sciences, Shiraz, Iran
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