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Scientific Reports Mar 2024This study aimed to quantitatively assess the thickness of the peripapillary retinal nerve fiber layer (pRNFL) thickness, as well as the microvascular alterations in the...
This study aimed to quantitatively assess the thickness of the peripapillary retinal nerve fiber layer (pRNFL) thickness, as well as the microvascular alterations in the macula and peripapillary regions, in optic nerve hypoplasia (ONH) patients compared to normal controls. This was achieved through the utilization of spectral-domain optical coherence tomography (SD-OCT) and optical coherence tomography angiography (OCTA), with a specific focus on elucidating the association between these structural alterations and visual acuity. We included a total of 17 eyes of 12 ONH patients, and 34 eyes of age-matched 34 healthy controls. The pRNFL thickness was quantified using SD-OCT, while OCTA facilitated the visualization and measurement of the microvascular structure images of the superficial retinal capillary plexus (SRCP), deep retinal capillary plexus (DRCP), and radial peripapillary capillary (RPC) segment in the macula and peripapillary area. pRNFL thickness was measured for eight sectors (superior, temporal, inferior, nasal, superotemporal, superonasal, inferotemporal, and inferonasal). SRCP, DRCP, and RPC were measured for four sectors (superior, temporal, inferior, and nasal). Age, gender, and spherical equivalent refractive errors were statistically adjusted for the analysis. Associations of structural parameters with visual acuity in ONH patients were analyzed using Spearman correlation analysis. pRNFL thickness was significantly thinner in ONH patients than in controls for all sectors. Vessel densities of temporal and nasal sectors in DRCP were significantly higher in ONH patients, but vessel densities of the inferior sector in RPC were significantly lower than those in controls. For all sectors, pRNFL thickness was strongly associated with visual acuity in ONH patients. ONH patients showed significant pRNFL thinning and microvascular alterations compared to controls, and pRNFL thickness was strongly associated with visual function. OCT and OCTA are useful tools for evaluating optic disc hypoplasia and its functional status.
Topics: Humans; Optic Disk; Optic Nerve Hypoplasia; Tomography, Optical Coherence; Visual Acuity; Angiography; Retinal Vessels; Fluorescein Angiography
PubMed: 38532111
DOI: 10.1038/s41598-024-57118-7 -
Molecular Medicine Reports May 2024Glaucoma is a group of progressive optic nerve disorders characterized by the loss of retinal ganglion cells, a thinner retinal nerve fibre layer and cupping of the... (Review)
Review
Glaucoma is a group of progressive optic nerve disorders characterized by the loss of retinal ganglion cells, a thinner retinal nerve fibre layer and cupping of the optic disk. Apoptosis is a physiological cell death process regulated by genes and plays a crucial role in maintaining tissue homeostasis, ensuring the natural development and immune defence of organisms. Apoptosis has been associated with glaucoma and inhibiting apoptosis by activating phosphatidylinositol 3-kinase‑protein kinase B or other medicines can rescue pathological changes in glaucoma. Due to the complex crosstalk of apoptosis pathways, the pathophysiological mechanism of apoptosis in glaucoma needs to be fully elucidated. The present review aimed to discuss the mechanism of cell apoptosis in glaucoma, improve the understanding of the pathophysiology of glaucoma, summarize new directions for the treatment of glaucoma and lay the foundation for new treatment strategies for glaucoma.
Topics: Humans; Glaucoma; Optic Disk; Optic Nerve Diseases; Apoptosis; Cell Death
PubMed: 38516770
DOI: 10.3892/mmr.2024.13207 -
F1000Research 2023Glaucoma comprises a group of disorders of the optic nerve that cause degenerative optic neuropathy, characterised by failure of neuroretinal rim tissue in the optic... (Review)
Review
Glaucoma comprises a group of disorders of the optic nerve that cause degenerative optic neuropathy, characterised by failure of neuroretinal rim tissue in the optic nerve head, retinal nerve fibre layer, and retinal ganglion cells. Glaucoma imposes a serious epidemiological threat, with an steady increase in the global number of cases. In the current ophthalmological practice, glaucoma is diagnosed via a series of examinations, including routine funduscopic examination, ocular tonometry, gonioscopy, measurement of the visual field, and assessment using the optical coherence tomography (OCT) technique. Nowadays, the OCT technique helps in systematising the diagnostic pathway and is a basic diagnostic tool for detection of early glaucomatous eye changes. It is also vital in assessing progression and monitoring treatment results of patients. The aim of this review was to present the OCT technique as a main tool in diagnosing and monitoring glaucoma.
Topics: Humans; Tomography, Optical Coherence; Glaucoma, Open-Angle; Glaucoma; Optic Disk; Optic Nerve Diseases
PubMed: 38511134
DOI: 10.12688/f1000research.139975.2 -
Scientific Reports Mar 2024Neurovascular coupling is a vital mechanism employed by the cerebrovascular system, including the eye, to regulate blood flow in periods of neuronal activation. This...
Neurovascular coupling is a vital mechanism employed by the cerebrovascular system, including the eye, to regulate blood flow in periods of neuronal activation. This study aims to investigate if laser speckle flowgraphy (LSFG) can detect coupling response elicited by flickering light stimuli and how variations in stimulus type and duration can affect the magnitude and evolution of blood flow in the optic nerve head (ONH) and peripapillary vessels. Healthy adults were exposed to two types of 10-Hz flicker stimuli: a photopic negative response-like stimulus (PhNR-S) or a visual evoked potential-like stimulus (VEP-S)-each presented in separate 10- and 60-s epochs. Both PhNR-S and VEP-S significantly increased ONH blood flow (p < 0.001) immediately after flicker cessation, with a trend of 60-s stimuli (PhNR-S = 11.6%; VEP-S = 10.4%) producing a larger response than 10-s stimuli (PhNR-S = 7.5%; VEP-S = 6.2%). Moreover, exposure to 60-s stimuli elicited a significantly prolonged ONH hyperemic response, especially with PhNR-S. Lastly, stimulation with either 60-s stimuli elicited a robust increase in blood flow within the peripapillary arterioles (p < 0.01) and venules (p < 0.01) as well. Flicker stimulation with common visual electrophysiology stimuli (PhNR-S and VEP-S) induced a demonstrable increase in ONH and peripapillary vessel blood flow, which varied with flicker duration. Our results validate that LSFG is a robust method to quantify flicker-induced hyperemic responses and to study neurovascular coupling in humans.
Topics: Adult; Humans; Optic Disk; Hyperemia; Evoked Potentials, Visual; Photic Stimulation; Blood Flow Velocity; Lasers; Regional Blood Flow; Laser-Doppler Flowmetry
PubMed: 38509194
DOI: 10.1038/s41598-024-57263-z -
Ophthalmic Research 2024Microcirculation of optic nerve head (ONH) in open-angle glaucoma (OAG) patients with unilateral visual field (VF) loss has yet to be fully investigated, especially the...
INTRODUCTION
Microcirculation of optic nerve head (ONH) in open-angle glaucoma (OAG) patients with unilateral visual field (VF) loss has yet to be fully investigated, especially the perimetrically unaffected fellow eyes.
METHODS
Thirty-eight OAG patients with VF defect in one eye and normal VF in the other eye, and thirty-one healthy participants were analyzed. All participants underwent laser speckle flowgraphy (LSFG), spectral-domain optical coherence tomography (SD-OCT) imaging, and VF test for further analyses. LSFG measurements included mean blur rate in all area of ONH (MA), big vessel area of ONH (MV), and tissue area of ONH (MT). SD-OCT parameters included circumpapillary retinal nerve fiber layer (cpRNFL) thickness and macula thicknesses. The difference of LSFG and SD-OCT indices between glaucoma patients and healthy controls were compared. The diagnostic accuracy was analyzed with the areas under the receiver operating characteristic curves (AROCs).
RESULTS
Global cpRNFL thickness and macular thickness in unaffected eyes of OAG patients were higher than their fellow eyes and lower than healthy eyes. MA and MV in healthy eyes and unaffected eyes were significantly higher than in affected eyes. MT in unaffected eyes of OAG patients was higher than in their fellow affected eyes but lower than in healthy eyes. The AROCs were highest for cpRNFL (0.925), followed by macular thickness (0.838), and MT (0.834).
CONCLUSIONS
ONH microcirculation in perimetrically unaffected fellow eyes was decreased in OAG patients with unilateral VF loss. LSFG can detect changes of ONH in high-risk eyes before detectable VF damage, which may reflect the vascular pathophysiology for glaucoma.
Topics: Humans; Glaucoma, Open-Angle; Male; Female; Optic Disk; Microcirculation; Visual Fields; Tomography, Optical Coherence; Middle Aged; Nerve Fibers; Retinal Ganglion Cells; Aged; Intraocular Pressure; Visual Field Tests; Laser-Doppler Flowmetry; ROC Curve; Retinal Vessels
PubMed: 38508153
DOI: 10.1159/000538407 -
Scientific Reports Mar 2024This study aimed to compare morphological differences of the neuroretinal rim between the temporally tilted and non-tilted optic discs in healthy eyes. We prospectively...
This study aimed to compare morphological differences of the neuroretinal rim between the temporally tilted and non-tilted optic discs in healthy eyes. We prospectively enrolled participants aged 20-40 years with temporally tilted or non-tilted optic discs. The optic nerve head parameters were analyzed using spectral domain-optical coherence tomography. The angle between the Bruch's membrane opening (BMO) plane and BMO-minimum rim width (BMO-MRW) was termed "BMO-MRW angle". Peripapillary retinal nerve fiber layer thickness (pRNFLT) and BMO-based parameters were compared between the temporally tilted and non-tilted disc groups. As a result, 55 temporally tilted disc eyes and 38 non-tilted disc eyes were analyzed. Global pRNFLT, global BMO-MRW, and total BMO-minimum rim area (BMO-MRA) were similar between the two groups (p = 0.138, 0.161, and p = 0.410, respectively). In the sectoral analysis, temporally tilted disc group exhibited thicker BMO-MRW in the temporal sector (p = 0.032) and thinner in the nasal superior and nasal sectors (p = 0.025 and p = 0.002, respectively). Temporally tilted disc group showed larger BMO-MRA in the temporal, temporal superior, and temporal inferior sectors (p < 0.001, p < 0.001, and p < 0.016, respectively), alongside a higher BMO-MRW angle in the temporal sector and lower in the nasal superior and nasal sectors. In conclusion, the neuroretinal rim, represented by BMO-MRW and BMO-MRA, showed morphological differences between temporally tilted and non-tilted optic discs in healthy eyes. BMO-MRW and BMO-MRA showed temporalization in the same manner as pRNFLT in the temporally tilted disc eyes. The BMO-MRW angle showed that in temporally tilted disc eyes, optic nerve fibers met the BMO plane steeply in the nasal sector and gently in the temporal sector than in non-tilted disc eyes, suggesting potential stress region of optic nerve fibers in temporally tilted disc eyes.
Topics: Humans; Optic Disk; Retinal Ganglion Cells; Retina; Bruch Membrane; Tomography, Optical Coherence; Intraocular Pressure
PubMed: 38480784
DOI: 10.1038/s41598-024-54116-7 -
Korean Journal of Ophthalmology : KJO Apr 2024Autoregulation of retinal vessels is stronger than that of choroidal vessels. This study aimed to use laser speckle flowgraphy to determine the time course of changes in...
PURPOSE
Autoregulation of retinal vessels is stronger than that of choroidal vessels. This study aimed to use laser speckle flowgraphy to determine the time course of changes in retinal hemodynamics of healthy eyes after a cold pressor test.
METHODS
This prospective study included 44 right eyes of 44 healthy volunteers (age, 21.7 ± 5.0 years). The mean blur rate, which is a quantitative index of the relative blood flow velocity in the retina, was measured using laser speckle flowgraphy. The vessel average of mean blur rate at the optic nerve head, intraocular pressure, systolic blood pressure, diastolic blood pressure, mean blood pressure, heart rate, and ocular perfusion pressure were evaluated at baseline, immediately after the cold pressor test, and 10, 20, and 30 minutes after the test.
RESULTS
Immediately after the test (0 minutes), systolic blood pressure, diastolic blood pressure, mean blood pressure, and ocular perfusion pressure were significantly increased compared with those at baseline; however, no changes were observed at 10, 20, and 30 minutes after the test. In contrast, intraocular pressure, heart rate, and the vascular mean blur rate values at the optic nerve head did not change throughout the course of the study.
CONCLUSIONS
Sympathetic hyperactivity induced by the cold pressor test increased systemic circulatory dynamics, but not retinal circulatory hemodynamics, suggesting the involvement of vascular autoregulation.
Topics: Humans; Adolescent; Young Adult; Adult; Optic Disk; Healthy Volunteers; Prospective Studies; Hemodynamics; Blood Pressure; Intraocular Pressure; Lasers; Regional Blood Flow
PubMed: 38476060
DOI: 10.3341/kjo.2023.0063 -
Arquivos Brasileiros de Oftalmologia 2024A 71-year-old woman presented a non-arteritic anterior ischemic optic neuropathy in an optic nerve with previously registered superonasal peripapillary myelinated nerve...
A 71-year-old woman presented a non-arteritic anterior ischemic optic neuropathy in an optic nerve with previously registered superonasal peripapillary myelinated nerve fibers. Her past medical history was significant for controlled systemic hypertension, hyperlipidemia, and diabetes mellitus. The physiologic cup was absent in both optic discs. Non-arteritic anterior ischemic optic neuropathy mainly affected the temporal and inferior sectors of the peripapillary retinal nerve fiber layer, as could be demonstrated by retinal nerve fiber layer optical coherence tomography and optic disc optical coherence tomography angiography. Unlike other published reports, just a slight regression of the myelinated nerve fibers was observed after 1 year of follow-up. This occurred because ischemia mainly affected the temporal and inferior peripapillary sectors, whereas myelinated nerve fibers were superonasal to the optic disc.
Topics: Humans; Female; Aged; Optic Neuropathy, Ischemic; Nerve Fibers, Myelinated; Optic Nerve; Optic Disk; Hypertension
PubMed: 38451679
DOI: 10.5935/0004-2749.2022-0237 -
Ophthalmology and Therapy May 2024To analyze the correlation between orbital compliance and retinal vessel density (VD) based on dynamic Scheimpflug analyzer (Corvis ST) and optical coherence tomographic...
Effect of Intraorbital Mechanical Compression on Retinal Microvascular Perfusion in Quiescent Thyroid-Associated Ophthalmopathy Based on Ocular Biomechanics Measured by Corvis ST.
INTRODUCTION
To analyze the correlation between orbital compliance and retinal vessel density (VD) based on dynamic Scheimpflug analyzer (Corvis ST) and optical coherence tomographic angiography (OCT-A).
METHODS
In this prospective observational study, 65 eyes of 44 patients with thyroid-associated ophthalmopathy (TAO) in quiescent stage were included (15 males and 29 females). The whole eye movement (WEM) was detected by Corvis ST. The superficial capillary plexus VD (SCP-VD) and deep capillary plexus VD (DCP-VD) were obtained by scanning the 3 × 3 mm area around the fovea using OCT-A, while the peripapillary vessel density (ppVD) was obtained by scanning the 4.5 × 4.5 mm area around the optic disk. Covariances including biomechanically corrected intraocular pressure (bIOP), axial length, age and gender were adjusted during data analysis.
RESULTS
The mean WEM of the participants was 0.235 ± 0.066 mm. The mean SCP-VD and DCP-VD in whole image were 46.20% ± 3.77% and 50.51% ± 3.96%; the mean whole pp-VD was 49.75% ± 2.01%. WEM was positively correlated with SCP-VD (r = 0.327, p = 0.01) and the whole pp-VD (r = 0.394, p < 0.01) after adjusting by gender, axial length (AL), age and bIOP, but it was not significantly correlated with DCP-VD (r = 0.072 p = 0.581).
CONCLUSION
Increase in orbital pressure might reduce retinal microvascular perfusion. Our data suggest orbital mechanical compression may be an important cause of retinal VD changes in quiescent patients with TAO.
PubMed: 38441857
DOI: 10.1007/s40123-024-00912-3 -
BMC Ophthalmology Mar 2024Intrapapillary hemorrhage with adjacent peripapillary subretinal hemorrhage is commonly observed in myopia with tilted optic disc. It presents with typical features on...
BACKGROUND
Intrapapillary hemorrhage with adjacent peripapillary subretinal hemorrhage is commonly observed in myopia with tilted optic disc. It presents with typical features on the fundus and follows a self-limiting course. However, due to its complex etiology, clinicians sometimes lack sufficient understanding of it which can easily lead to misdiagnosis or overtreatment. In this case report, we describe a rare case of intrapapillary hemorrhage with adjacent peripapillary subretinal hemorrhage in both eyes.
CASE PRESENTATION
An 18-year-old female who has no past medical history experienced sudden black shadow blocking of her right eye in the right eye for the past 2 days after a 5-day history of COVID-19 infection. The best corrected visual acuity is 0.5 in the right eye and 0.6 in the left eye. Optical coherence tomography (OCT) showed tilted optic discs in both eyes, bulged nasal optic discs, and the presence of strong reflective material under the parafoveal retina of the optic discs. Fundus fluorescein angiography (FFA) showed subretinal fluorescence occlusion above and nasolateral to the optic disc in the right eye, with hypofluorescence below the optic disc; the subretinal below the optic disc was obscured by vitreous hemorrhage; hypofluorescence was seen in the optic disc region of the left eye.COVID-19 antigen was positive. The patient was in the early stage of the third COVID-19 infection when the disease occurred. We speculate that it may be related to it. After 5 months of conservative treatment, the patient's hemorrhage disappeared in both eyes and her best corrected visual acuity returned to normal.
CONCLUSIONS
Intrapapillary hemorrhage with adjacent peripapillary subretinal hemorrhage usually occurs in myopia with tilted optic disc. In most patients, the cause of the bleeding is unknown, but it can gradually resolve under clinical observation or conservative treatment.
Topics: Humans; Female; Adolescent; COVID-19; Retinal Hemorrhage; Optic Disk; Myopia; Vitreous Hemorrhage
PubMed: 38439046
DOI: 10.1186/s12886-024-03368-y