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Wostyn P. Targeting the Cerebrospinal Fluid Compartment in Glaucoma: Still the Dark Side of the Moon? Comment on Passaro et al. Glaucoma as a Tauopathy-Is It the Missing Piece in the Glaucoma Puzzle? J. Clin. Med. 2023, 12, 6900. J Clin Med 2024; 13:827. [PMID: 38337521 PMCID: PMC10856522 DOI: 10.3390/jcm13030827] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2024] [Revised: 01/20/2024] [Accepted: 01/29/2024] [Indexed: 02/12/2024] Open
Abstract
I read with great interest the article by Passaro et al [...].
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Affiliation(s)
- Peter Wostyn
- Department of Psychiatry, PC Sint-Amandus, 8730 Beernem, Belgium
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Donato L, Mordà D, Scimone C, Alibrandi S, D’Angelo R, Sidoti A. Bridging Retinal and Cerebral Neurodegeneration: A Focus on Crosslinks between Alzheimer-Perusini's Disease and Retinal Dystrophies. Biomedicines 2023; 11:3258. [PMID: 38137479 PMCID: PMC10741418 DOI: 10.3390/biomedicines11123258] [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: 11/01/2023] [Revised: 12/02/2023] [Accepted: 12/07/2023] [Indexed: 12/24/2023] Open
Abstract
In the early stages of Alzheimer-Perusini's disease (AD), individuals often experience vision-related issues such as color vision impairment, reduced contrast sensitivity, and visual acuity problems. As the disease progresses, there is a connection with glaucoma and age-related macular degeneration (AMD) leading to retinal cell death. The retina's involvement suggests a link with the hippocampus, where most AD forms start. A thinning of the retinal nerve fiber layer (RNFL) due to the loss of retinal ganglion cells (RGCs) is seen as a potential AD diagnostic marker using electroretinography (ERG) and optical coherence tomography (OCT). Amyloid beta fragments (Aβ), found in the eye's vitreous and aqueous humor, are also present in the cerebrospinal fluid (CSF) and accumulate in the retina. Aβ is known to cause tau hyperphosphorylation, leading to its buildup in various retinal layers. However, diseases like AD are now seen as mixed proteinopathies, with deposits of the prion protein (PrP) and α-synuclein found in affected brains and retinas. Glial cells, especially microglial cells, play a crucial role in these diseases, maintaining immunoproteostasis. Studies have shown similarities between retinal and brain microglia in terms of transcription factor expression and morphotypes. All these findings constitute a good start to achieving better comprehension of neurodegeneration in both the eye and the brain. New insights will be able to bring the scientific community closer to specific disease-modifying therapies.
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Affiliation(s)
- Luigi Donato
- Department of Biomedical and Dental Sciences and Morphofunctional Imaging, Division of Medical Biotechnologies and Preventive Medicine, University of Messina, 98122 Messina, Italy; (L.D.); (C.S.); (R.D.); (A.S.)
- Department of Biomolecular Strategies, Genetics, Cutting-Edge Therapies, Euro-Mediterranean Institute of Science and Technology (I.E.ME.S.T.), 90139 Palermo, Italy;
| | - Domenico Mordà
- Department of Biomolecular Strategies, Genetics, Cutting-Edge Therapies, Euro-Mediterranean Institute of Science and Technology (I.E.ME.S.T.), 90139 Palermo, Italy;
- Department of Veterinary Sciences, University of Messina, 98122 Messina, Italy
| | - Concetta Scimone
- Department of Biomedical and Dental Sciences and Morphofunctional Imaging, Division of Medical Biotechnologies and Preventive Medicine, University of Messina, 98122 Messina, Italy; (L.D.); (C.S.); (R.D.); (A.S.)
- Department of Biomolecular Strategies, Genetics, Cutting-Edge Therapies, Euro-Mediterranean Institute of Science and Technology (I.E.ME.S.T.), 90139 Palermo, Italy;
| | - Simona Alibrandi
- Department of Biomedical and Dental Sciences and Morphofunctional Imaging, Division of Medical Biotechnologies and Preventive Medicine, University of Messina, 98122 Messina, Italy; (L.D.); (C.S.); (R.D.); (A.S.)
- Department of Biomolecular Strategies, Genetics, Cutting-Edge Therapies, Euro-Mediterranean Institute of Science and Technology (I.E.ME.S.T.), 90139 Palermo, Italy;
| | - Rosalia D’Angelo
- Department of Biomedical and Dental Sciences and Morphofunctional Imaging, Division of Medical Biotechnologies and Preventive Medicine, University of Messina, 98122 Messina, Italy; (L.D.); (C.S.); (R.D.); (A.S.)
| | - Antonina Sidoti
- Department of Biomedical and Dental Sciences and Morphofunctional Imaging, Division of Medical Biotechnologies and Preventive Medicine, University of Messina, 98122 Messina, Italy; (L.D.); (C.S.); (R.D.); (A.S.)
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Lee SH, Kim TW, Lee EJ, Kil H. Reply to Wostyn, P. Could Young Cerebrospinal Fluid Combat Glaucoma? Comment on "Lee et al. Association between Optic Nerve Sheath Diameter and Lamina Cribrosa Morphology in Normal-Tension Glaucoma. J. Clin. Med. 2023, 12, 360". J Clin Med 2023; 12:jcm12113784. [PMID: 37297979 DOI: 10.3390/jcm12113784] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2023] [Revised: 05/23/2023] [Accepted: 05/30/2023] [Indexed: 06/12/2023] Open
Abstract
We are pleased to see that Peter Wostyn has contributed a Comment: "Could Young Cerebrospinal Fluid Combat Glaucoma?" [...].
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Affiliation(s)
- Seung Hyen Lee
- Department of Ophthalmology, Nowon Eulji Medical Center, Eulji University College of Medicine, Seoul 01830, Republic of Korea
| | - Tae-Woo Kim
- Department of Ophthalmology, Seoul National University Bundang Hospital, Seoul National University College of Medicine, Seongnam 13620, Republic of Korea
| | - Eun Ji Lee
- Department of Ophthalmology, Seoul National University Bundang Hospital, Seoul National University College of Medicine, Seongnam 13620, Republic of Korea
| | - Hyunkyung Kil
- Department of Ophthalmology, Bundang Jesaeng General Hospital, Seongnam 13590, Republic of Korea
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Ashraf G, McGuinness M, Khan MA, Obtinalla C, Hadoux X, van Wijngaarden P. Retinal imaging biomarkers of Alzheimer's disease: A systematic review and meta-analysis of studies using brain amyloid beta status for case definition. ALZHEIMER'S & DEMENTIA (AMSTERDAM, NETHERLANDS) 2023; 15:e12421. [PMID: 37250908 PMCID: PMC10210353 DOI: 10.1002/dad2.12421] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/17/2022] [Revised: 03/03/2023] [Accepted: 03/07/2023] [Indexed: 05/31/2023]
Abstract
Introduction We performed a systematic review and meta-analysis of the association between retinal imaging parameters and Alzheimer's disease (AD). Methods PubMed, EMBASE, and Scopus were systematically searched for prospective and observational studies. Included studies had AD case definition based on brain amyloid beta (Aβ) status. Study quality assessment was performed. Random-effects meta-analyses of standardized mean difference, correlation, and diagnostic accuracy were conducted. Results Thirty-eight studies were included. There was weak evidence of peripapillary retinal nerve fiber layer thinning on optical coherence tomography (OCT) (p = 0.14, 11 studies, n = 828), increased foveal avascular zone area on OCT-angiography (p = 0.18, four studies, n = 207), and reduced arteriole and venule vessel fractal dimension on fundus photography (p < 0.001 and p = 0.08, respectively, three studies, n = 297) among AD cases. Discussion Retinal imaging parameters appear to be associated with AD. Small study sizes and heterogeneity in imaging methods and reporting make it difficult to determine utility of these changes as AD biomarkers. Highlights We performed a systematic review on retinal imaging and Alzheimer's disease (AD).We only included studies in which cases were based on brain amyloid beta status.Several retinal biomarkers were associated with AD but clinical utility is uncertain.Studies should focus on biomarker-defined AD and use standardized imaging methods.
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Affiliation(s)
- Gizem Ashraf
- Centre for Eye Research AustraliaRoyal Victorian Eye and Ear HospitalMelbourneVictoriaAustralia
- OphthalmologyDepartment of SurgeryUniversity of MelbourneMelbourneVictoriaAustralia
| | - Myra McGuinness
- Centre for Eye Research AustraliaRoyal Victorian Eye and Ear HospitalMelbourneVictoriaAustralia
- Centre for Epidemiology and BiostatisticsMelbourne School of Population and Global HealthUniversity of MelbourneMelbourneVictoriaAustralia
| | - Muhammad Azaan Khan
- Faculty of Medicine and HealthUniversity of New South WalesSydneyNew South WalesAustralia
| | - Czarina Obtinalla
- Discipline of OrthopticsSchool of Allied HealthHuman Services & SportCollege of ScienceHealth & EngineeringLa Trobe UniversityMelbourneVictoriaAustralia
| | - Xavier Hadoux
- Centre for Eye Research AustraliaRoyal Victorian Eye and Ear HospitalMelbourneVictoriaAustralia
| | - Peter van Wijngaarden
- Centre for Eye Research AustraliaRoyal Victorian Eye and Ear HospitalMelbourneVictoriaAustralia
- OphthalmologyDepartment of SurgeryUniversity of MelbourneMelbourneVictoriaAustralia
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Gavrilova NA, Kutrovskaya NY, Salimova KN. Optical coherence tomography and optical coherence tomography — angiography used in endocrine ophthalmopathy. RUSSIAN OPHTHALMOLOGICAL JOURNAL 2023. [DOI: 10.21516/2072-0076-2023-16-1-145-150] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 03/22/2023]
Abstract
The literature review presents the results of optical coherence tomography and optical coherence tomography — angiography used for Graves’ orbitopathy. The data on the thickness of the inner layers of the retina, microcirculation in the peripapillary and macular regions, parameters of the choroid, lamina cribrosa and extraocular muscles were analyzed as possible diagnostic criteria of the condition.
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Optical Coherence Tomography Imaging of the Lamina Cribrosa: Structural Biomarkers in Nonglaucomatous Diseases. J Ophthalmol 2021; 2021:8844614. [PMID: 33680508 PMCID: PMC7910045 DOI: 10.1155/2021/8844614] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2020] [Revised: 01/28/2021] [Accepted: 02/05/2021] [Indexed: 12/13/2022] Open
Abstract
The lamina cribrosa (LC) is an active structure that responds to the strain by changing its morphology. Abnormal changes in LC morphology are usually associated with, and indicative of, certain pathologies such as glaucoma, intraocular hypertension, and myopia. Recent developments in optical coherence tomography (OCT) have enabled detailed in vivo studies about the architectural characteristics of the LC. Structural characteristics of the LC have been widely explored in glaucoma management. However, information about which LC biomarkers could be useful for the diagnosis, and follow-up, of other diseases besides glaucoma is scarce. Hence, this literature review aims to summarize the role of the LC in nonophthalmic and ophthalmic diseases other than glaucoma. PubMed was used to perform a systematic review on the LC features that can be extracted from OCT images. All imaging features are presented and discussed in terms of their importance and applicability in clinical practice. A total of 56 studies were included in this review. Overall, LC depth (LCD) and thickness (LCT) have been the most studied features, appearing in 75% and 45% of the included studies, respectively. These biomarkers were followed by the prelaminar tissue thickness (21%), LC curvature index (5.4%), LC global shape index (3.6%), LC defects (3.6%), and LC strains/deformations (1.8%). Overall, the disease groups showed a thinner LC (smaller LCT) and a deeper ONH cup (larger LCD), with some exceptions. A large variability between approaches used to compute LC biomarkers has been observed, highlighting the importance of having automated and standardized methodologies in LC analysis. Moreover, further studies are needed to identify the pathologies where LC features have a diagnostic and/or prognostic value.
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Song A, Johnson N, Ayala A, Thompson AC. Optical Coherence Tomography in Patients with Alzheimer's Disease: What Can It Tell Us? Eye Brain 2021; 13:1-20. [PMID: 33447120 PMCID: PMC7802785 DOI: 10.2147/eb.s235238] [Citation(s) in RCA: 22] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2020] [Accepted: 12/09/2020] [Indexed: 12/17/2022] Open
Abstract
PURPOSE Although Alzheimer's disease (AD) is a leading cause of dementia worldwide, its clinical diagnosis remains a challenge. Optical coherence tomography (OCT) and OCT with angiography (OCTA) are non-invasive ophthalmic imaging tools with the potential to detect retinal structural and microvascular changes in patients with AD, which may serve as biomarkers for the disease. In this systematic review, we evaluate whether certain OCT and OCTA parameters are significantly associated with AD and mild cognitive impairment (MCI). METHODS PubMed database was searched using a combination of MeSH terms to identify studies for review. Studies were organized by participant diagnostic groups, type of imaging modality, and OCT/OCTA parameters of interest. Participant demographic data was also collected and baseline descriptive statistics were calculated for the included studies. RESULTS Seventy-one studies were included for review, representing a total of 6757 patients (2350 AD, 793 MCI, 2902 healthy controls (HC), and 841 others with a range of other neurodegenerative diagnoses). The mean baseline ages were 72.78±3.69, 71.52±2.88, 70.55±3.85 years for AD, MCI and HC groups, respectively. The majority of studies noted significant structural and functional decline in AD patients when compared to HC. Although analysis of MCI groups yielded more mixed results, a similar pattern of decline was often noted amongst patients with MCI relative to HC. OCT and OCTA measurements were also shown to correlate with established measures of AD such as neuropsychological testing or neuroimaging. CONCLUSION OCT and OCTA show great potential as non-invasive technologies for the diagnosis of AD. However, further research is needed to determine whether there are AD-specific patterns of structural or microvascular change in the retina and optic nerve that distinguish AD from other neurodegenerative diseases. Development of sensitive and specific OCT/OCTA parameters will be necessary before they can be used to detect AD in clinical settings.
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Affiliation(s)
- Ailin Song
- Duke University School of Medicine, Durham, NC, USA
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Retinal Degeneration and Alzheimer's Disease: An Evolving Link. Int J Mol Sci 2020; 21:ijms21197290. [PMID: 33023198 PMCID: PMC7582766 DOI: 10.3390/ijms21197290] [Citation(s) in RCA: 69] [Impact Index Per Article: 17.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2020] [Revised: 09/15/2020] [Accepted: 09/25/2020] [Indexed: 12/13/2022] Open
Abstract
Age-related macular degeneration (AMD) and glaucoma are degenerative conditions of the retina and a significant cause of irreversible blindness in developed countries. Alzheimer’s disease (AD), the most common dementia of the elderly, is often associated with AMD and glaucoma. The cardinal features of AD include extracellular accumulation of amyloid β (Aβ) and intracellular deposits of hyper-phosphorylated tau (p-tau). Neuroinflammation and brain iron dyshomeostasis accompany Aβ and p-tau deposits and, together, lead to progressive neuronal death and dementia. The accumulation of Aβ and iron in drusen, the hallmark of AMD, and Aβ and p-tau in retinal ganglion cells (RGC), the main retinal cell type implicated in glaucoma, and accompanying inflammation suggest overlapping pathology. Visual abnormalities are prominent in AD and are believed to develop before cognitive decline. Some are caused by degeneration of the visual cortex, while others are due to RGC loss or AMD-associated retinal degeneration. Here, we review recent information on Aβ, p-tau, chronic inflammation, and iron dyshomeostasis as common pathogenic mechanisms linking the three degenerative conditions, and iron chelation as a common therapeutic option for these disorders. Additionally discussed is the role of prion protein, infamous for prion disorders, in Aβ-mediated toxicity and, paradoxically, in neuroprotection.
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Lee SH, Han JW, Lee EJ, Kim TW, Kim H, Kim KW. Cognitive Impairment and Lamina Cribrosa Thickness in Primary Open-Angle Glaucoma. Transl Vis Sci Technol 2020; 9:17. [PMID: 32832224 PMCID: PMC7414686 DOI: 10.1167/tvst.9.7.17] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2019] [Accepted: 04/28/2020] [Indexed: 11/24/2022] Open
Abstract
Purpose The purpose of this study was to investigate the relationship between the lamina cribrosa (LC) thickness (LCT) as assessed using enhanced depth-imaging (EDI) optical coherence tomography (OCT) and cognitive function in primary open-angle glaucoma (POAG). Methods The study consisted of 105 POAG eyes and 23 nonglaucomatous control eyes that completed neuropsychological tests. The optic nerve heads of the patients were imaged using EDI-OCT. B-scan images were constructed in three dimensions using maximum intensity projection (MIP), and the LCT was measured using the thin-slab MIP images. A comprehensive battery consisting of 15 neuropsychological tests was used to evaluate cognitive function. Results POAG eyes had smaller mean LCT as compared with control eyes (P < 0.001). Age and Mini Mental State Examination (MMSE) scores did not differ between the two groups. Linear regression analysis revealed that lower scores on the MMSE (P < 0.001), presence of glaucoma (P = 0.006), and a smaller global retinal nerve fiber layer thickness (P < 0.001) were independently associated with a smaller mean LCT. Davies' test revealed a statistically significant breakpoint for the mean LCT (221.14 µm), below which a smaller MMSE score was significantly associated with a smaller mean LCT. In POAG eyes with a mean LCT smaller than the breakpoint (< 221.14 µm), not only the global cognition but also the visuospatial function and visual memory were worse than in those with a larger mean LCT (all P ≤ 0.003). Conclusions Impairment of cognitive function was observed in patients with POAG with a thinner LC. The role of LC imaging as a potential biomarker to monitor cognitive impairment needs further investigation. Translational Relevance LC thinning may reflect a shared mechanism of neurodegenerative diseases in the brain and optic nerve.
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Affiliation(s)
- Seung Hyen Lee
- Department of Ophthalmology, Bundang Jesaeng General Hospital, Daejin Medical Center, Seongnam, Korea
| | - Ji Won Han
- Department of Neuropsychiatry, Seoul National University College of Medicine, Seoul National University Bundang Hospital, Seongnam, Korea
| | - Eun Ji Lee
- Department of Ophthalmology, Seoul National University College of Medicine, Seoul National University Bundang Hospital, Seongnam, Korea
| | - Tae-Woo Kim
- Department of Ophthalmology, Seoul National University College of Medicine, Seoul National University Bundang Hospital, Seongnam, Korea
| | - Hyunjoong Kim
- Department of Applied Statistics, Yonsei University, Seoul, Korea
| | - Ki Woong Kim
- Department of Neuropsychiatry, Seoul National University College of Medicine, Seoul National University Bundang Hospital, Seongnam, Korea.,Department of Brain and Cognitive Science, Seoul National University College of Natural Sciences, Seoul, Korea.,Department of Psychiatry, Seoul National University College of Medicine, Seoul, Korea
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Xu L, Yu H, Sun H, Hu B, Geng Y. Dietary Melatonin Therapy Alleviates the Lamina Cribrosa Damages in Patients with Mild Cognitive Impairments: A Double-Blinded, Randomized Controlled Study. Med Sci Monit 2020; 26:e923232. [PMID: 32376818 PMCID: PMC7233010 DOI: 10.12659/msm.923232] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2020] [Accepted: 03/19/2020] [Indexed: 12/11/2022] Open
Abstract
BACKGROUND Alzheimer's disease (AD) is a degenerative disease that is characterized by massive neuron devastations in the hippocampus and cortex. Mild cognitive impairment (MCI) is the transitory stage between normality and AD dementia. This study aimed to investigate the melatonin induced effects on the lamina cribrosa thickness (LCT) of patients with MCI. MATERIAL AND METHODS The LCT data of patients with MCI were compared to LCT data of healthy controls. Subsequently, all MCI patients were randomly assigned into an experimental group (with melatonin treatment) or a placebo group (without any melatonin treatment). RESULTS The LCT of MCI patients decreased significantly compared with healthy controls. The univariate analysis showed that the lower the Mini Mental State Examination (MMSE) score (P=0.038; 95% CI: 0.876, -0.209), the smaller hippocampus volume (P=0.001; 95% CI: -1.594, -2.911), and the upregulated level of cerebrospinal fluid (CSF) T-tau (P=0.036; 95% CI: 2.546, -0.271) were associated significantly with the thinner LCT in MCI patients. There were 40 patients in the experimental group and 39 patients in the placebo group. The mean age of the experimental group was not significantly different from the placebo group (66.3±8.8 versus 66.5±8.3; P>0.05). The LCT and hippocampus volume of the melatonin treated group were significantly larger compared with the placebo group (P<0.001). On the other hand, the CSF T-tau level of the melatonin treated group was significantly lower compared with the untreated group (P<0.001). CONCLUSIONS LCT assessment might allow early diagnosis of MCI. Dietary melatonin therapy could provide an effective medication for MCI patients with LCT alterations.
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Affiliation(s)
- Lei Xu
- Department of Thoracic Surgery, China-Japan Union Hospital of Jilin University, Changchun, Jilin, P.R. China
| | - Haixiang Yu
- Department of Thoracic Surgery, China-Japan Union Hospital of Jilin University, Changchun, Jilin, P.R. China
| | - Hongbin Sun
- Department of Thoracic Surgery, China-Japan Union Hospital of Jilin University, Changchun, Jilin, P.R. China
| | - Bang Hu
- Department of Colorectal Surgery, The Sixth Affiliated Hospital, Sun Yat-sen University, Guangzhou, Guangdong, P.R. China
| | - Yi Geng
- Department of Neurosurgery, Liaohe Oil Gem Flower Hospital, Panjin, Liaoning, P.R. China
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Georgevsky D, Gangoda SVS, Golzan SM. Postural effects on spontaneous retinal venous pulsations in healthy individuals. Acta Ophthalmol 2019; 97:e839-e843. [PMID: 30806039 DOI: 10.1111/aos.14068] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2018] [Accepted: 02/02/2019] [Indexed: 11/30/2022]
Abstract
PURPOSE To assess amplitudes of spontaneous retinal venous pulsations (SVP) in three various postures (sitting, supine and lateral decubitus) in healthy individuals. METHODS Thirty participants (28 ± 8 years, 25 females) were included in the study. Intraocular pressure (IOP), blood pressure (BP) and SVP's were measured at three different postures using a calibrated Tono-Pen applanation tonometer, a digital sphygmomanometer, and a custom-built handheld video ophthalmoscope, respectively. Retinal venous pulsations (SVP) amplitudes were extracted from the retinal videos using a custom written MATLAB algorithm. Mean arterial pressure (MAP = (systolic + 2diastolic)/3) and mean ocular perfusion pressure (MOPP = (2/3 MAP)-IOP) were also calculated at each posture. A one-way ANOVA was applied to each parameter to determine any significant difference for the various postural changes. RESULTS Mean IOP increased (p < 0.0001) and mean SVP decreased (p < 0.0001) from sitting to supine. The mean IOP (mmHg) and SVP (MU; measuring units) in sitting, supine and lateral decubitus were 16.2 ± 2, 19.4 ± 4, 19.8 ± 2 mmHg and 5.8 ± 2, 4.5 ± 2, and 4.7 ± 2 MU, respectively. Mean arterial pressure (MAP) and MOPP also decreased significantly from sitting to supine (p < 0.001, p < 0.001) and sitting to lateral decubitus (p < 0.05, p < 0.01). There were no significant differences between IOP, SVP, MAP or MOPP during a postural modification from supine to lateral decubitus. CONCLUSIONS In this study, we showed a significant reduction in SVP amplitudes and a significant increase in IOP from sitting to supine position in a healthy young cohort. This supports the rationale to further study such phenomenon in ocular conditions such as glaucoma to determine whether relative SVP change, for a similar postural change, can reveal early signs of vascular dysfunction.
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Affiliation(s)
- Dana Georgevsky
- Vision Science group Graduate School of Health (Orthoptics Discipline) University of Technology Sydney Ultimo NSW Australia
| | - Sumudu V. S. Gangoda
- Department of Biomedical Sciences Faculty of Medicine and Health Sciences Macquarie University Sydney NSW Australia
| | - Seyyed Mojtaba Golzan
- Vision Science group Graduate School of Health (Orthoptics Discipline) University of Technology Sydney Ultimo NSW Australia
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