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Current Journal of Neurology Jan 2023This study was conducted to evaluate the relationship between retinal layer thickness (RLT) and cognition in patients with multiple sclerosis (MS). We searched PubMed,... (Review)
Review
This study was conducted to evaluate the relationship between retinal layer thickness (RLT) and cognition in patients with multiple sclerosis (MS). We searched PubMed, Scopus, Embase, Web of Science, and Google Scholar. The search strategy included the MeSH and text words as ["ora serrata" OR "retina" OR ("coherence tomography" AND "optical") OR "OCT tomography" OR (tomography AND OCT) OR "optical coherence tomography" OR "OCT" OR "retinal thickness" OR "inner plexiform layer" OR "nerve fiber layer" OR "ganglion cell layer" OR "inner nuclear layer" OR "outer plexiform layer" OR "outer nuclear layer" OR "external limiting membrane" OR "inner segment layer" OR "outer segment layer" OR "retinal pigment epithelium"] AND ["cognition"* OR "cognitive function"* OR (function* AND cognitive)] AND [(sclerosis AND multiple) OR (sclerosis AND disseminated) OR "disseminated sclerosis" OR "multiple sclerosis" OR "acute fulminating"]. The literature search revealed 1090 articles; after deleting duplicates, 980 remained. Finally, 14 studies were included. Totally, 1081 patients were evaluated. Mean age ranged from 31 to 55 years. In some studies, there was a correlation between cognition and retinal thickness, while others did not confirm this finding. Some authors found cognitive impairment (CI) in patients with MS with RLT. The results of this systematic review show that there are discrepancies between the results of studies regarding the relationship between RLT and cognition status in patients with MS. Further studies with more included original studies and meta-analysis are recommended.
PubMed: 38011353
DOI: 10.18502/cjn.v22i1.12617 -
BioMed Research International 2015Glaucoma is a multifactorial disease that is the leading cause of irreversible blindness. Recent data documented that glaucoma is not limited to the retinal ganglion... (Review)
Review
Glaucoma is a multifactorial disease that is the leading cause of irreversible blindness. Recent data documented that glaucoma is not limited to the retinal ganglion cells but that it also extends to the posterior visual pathway. The diagnosis is based on the presence of signs of glaucomatous optic neuropathy and consistent functional visual field alterations. Unfortunately these functional alterations often become evident when a significant amount of the nerve fibers that compose the optic nerve has been irreversibly lost. Advanced morphological and functional magnetic resonance (MR) techniques (morphometry, diffusion tensor imaging, arterial spin labeling, and functional connectivity) may provide a means for observing modifications induced by this fiber loss, within the optic nerve and the visual cortex, in an earlier stage. The aim of this systematic review was to determine if the use of these advanced MR techniques could offer the possibility of diagnosing glaucoma at an earlier stage than that currently possible.
Topics: Diagnostic Techniques, Ophthalmological; Glaucoma; Humans; Magnetic Resonance Imaging
PubMed: 26167474
DOI: 10.1155/2015/160454 -
International Ophthalmology Sep 2021Retinal nerve fiber/ganglion cell layer (RNFL/GCL) thickness measured using optical coherence tomography has been proposed as an ocular biomarker for children with... (Meta-Analysis)
Meta-Analysis Review
The association between attention-deficit/hyperactivity disorder and retinal nerve fiber/ganglion cell layer thickness measured by optical coherence tomography: a systematic review and meta-analysis.
PURPOSE
Retinal nerve fiber/ganglion cell layer (RNFL/GCL) thickness measured using optical coherence tomography has been proposed as an ocular biomarker for children with attention-deficit/hyperactivity disorder (ADHD), but findings varied in different studies. This study aims to determine the association between RNFL/GCL thickness and ADHD in children by systematic review and meta-analysis.
METHODS
We performed a literature search in Embase, PubMed, Medline, Web of Science, and PsycINFO for relevant articles published up to February 29, 2020. All studies with original data comparing RNFL/GCL thickness in ADHD and healthy children were included. The Newcastle Ottawa Scale was used to assess bias risk and quality of evidence. Pooled estimates of the differences in thickness of RNFL or GCL between ADHD and healthy subjects were generated using meta-analysis with a random-effect model due to significant inter-study heterogeneity. Sensitivity analysis was also performed.
RESULTS
We identified four eligible studies involving a total of 164 ADHD and 150 control subjects. Meta-analysis revealed that ADHD in children was associated with a reduction in global RNFL thickness (SMD, - 0.23; 95% CI - 0.46, - 0.01; p = 0.04). The global GCL thickness was examined in two studies with 89 ADHD and 75 control subjects, but the pooled difference in global GCL thickness between ADHD children and controls was not statistically significant (SMD, - 0.34; 95% CI - 1.25, 0.58; p = 0.47).
CONCLUSION
Existing evidence suggests a possible association between ADHD and RNFL thinning in children. In view of the limited number of reports, further studies in large cohorts should be warranted.
Topics: Attention Deficit Disorder with Hyperactivity; Humans; Nerve Fibers; Retina; Retinal Ganglion Cells; Tomography, Optical Coherence
PubMed: 34014463
DOI: 10.1007/s10792-021-01852-8 -
Journal of Cataract and Refractive... Sep 2015This review looked at the effect of cataract surgery on the regulation of circadian rhythms and compared the effect of blue light-filtering and clear intraocular lenses... (Meta-Analysis)
Meta-Analysis Review
UNLABELLED
This review looked at the effect of cataract surgery on the regulation of circadian rhythms and compared the effect of blue light-filtering and clear intraocular lenses (IOLs) on circadian rhythms. A systematic review and metaanalysis were performed, and the level of evidence was evaluated based on the principles described in the Grading of Recommendations Assessment, Development, and Evaluation system. A literature search of PubMed, Embase, and Cochrane Library databases was performed, as well as a search for unpublished trials at the U.S. National Institutes of Health Clinical Trials web site. Trials that reported the effect of cataract surgery on circadian rhythms were included. Outcomes were the Pittsburgh Sleep Quality Index (PSQI) global score, number of poor sleepers, Epworth Sleepiness Score, sleep efficiency, and mean concentration of melatonin. Cataract surgery improved regulation of circadian rhythms measured by the PSQI questionnaire, but the clinical relevance is uncertain. There was no difference between the effect of the 2 IOL types.
FINANCIAL DISCLOSURE
No author has a financial or proprietary interest in any material or method mentioned.
Topics: Aging; Cataract Extraction; Circadian Rhythm; Humans; Lens Implantation, Intraocular; Lenses, Intraocular; Retinal Ganglion Cells; Rod Opsins; Sleep Wake Disorders
PubMed: 26603409
DOI: 10.1016/j.jcrs.2015.09.009 -
Neurological Sciences : Official... Mar 2021Migraine is one of the most common disabling diseases in the world. Its recurrent attacks may lead to abnormalities in the structure of the brain and retina. An... (Meta-Analysis)
Meta-Analysis Review
BACKGROUND
Migraine is one of the most common disabling diseases in the world. Its recurrent attacks may lead to abnormalities in the structure of the brain and retina. An increasing number of studies have investigated retinal nerve fiber layer (RNFL) thickness alterations in migraine by the optical coherence tomography (OCT); however, no consensus has yet reached.
METHOD
We searched Pubmed, Embase, and Web of Science databases to identify studies that investigated RNFL thickness in migraine by OCT measurement and performed a meta-analysis of eligible studies.
RESULTS
Twenty-six studies were included in the meta-analysis, comprising 1530 migraine patients and 1105 healthy controls. The mean RNFL thickness was thinner in the migraine group compared to the control group (SMD =- 0.53). In the subgroup analyses, RNFL thickness were decreased most significantly in the superior (SMD = - 0.71) and inferior (SMD = - 0.63) quadrants among all quadrants. Migraine with aura (SMD = - 0.91) showed a greater effect size of RNFL thickness reduction than migraine without aura (SMD =- 0.47). Spectral-domain OCT (SMD = - 0.55) seems more sensitive to detect RNFL thickness reduction than time-domain OCT (SMD = - 0.44). In addition, age, sex, disease duration, attack frequency, and intraocular pressure were not significantly associated with RNFL thickness.
CONCLUSIONS
The findings from our comprehensive meta-analysis with large datasets strengthen the clinical evidence of the RNFL thickness reduction in migraine. RNFL thickness via spectral-domain OCT measurement demonstrates the potential role in differentiating patients with migraine, especially migraine with aura, from healthy controls.
Topics: Humans; Migraine Disorders; Nerve Fibers; Retina; Retinal Ganglion Cells; Tomography, Optical Coherence
PubMed: 33439389
DOI: 10.1007/s10072-020-04992-4 -
Journal of Neurology Mar 2023Several studies report mixed associations between the retinal nerve fiber layer (RNFL) thickness with cognitive and physical disability in persons with multiple... (Meta-Analysis)
Meta-Analysis Review
BACKGROUND
Several studies report mixed associations between the retinal nerve fiber layer (RNFL) thickness with cognitive and physical disability in persons with multiple sclerosis (PwMS). Systematic synthesis of these findings is crucial in deriving credible conclusions.
METHODS
Five databases were searched from their inception to March 2022. The inclusion criteria for studies were MS-specific and required RNFL and cognitive performance data in order to be analyzed. The selection processes followed the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines.
RESULTS
The systematic review yielded 31 studies that investigated the association between RNFL thickness and cognitive performance. Twenty-two studies reported positive associations, and nine did not. The meta-analysis included 11 studies with a total of 782 PwMS with mean age of 40.5 years, mean Expanded Disability Status Scale (EDSS) of 2.7, and disease duration of 11.3 years. RNFL thickness was significantly associated Symbol Digit Modalities Test (pooled r = 0.306, p < 0.001), Paced Auditory Serial Addition Test (pooled r = 0.374, p < 0.001) and Word List Generation (WLG, pooled r = 0.177, p < 0.001). RNFL was also significantly correlated with visuospatial learning and memory tests (pooled r = 0.148, p = 0.042) and verbal learning and memory tests (pooled r = 0.245, p = 0.005). Within three eligible studies, no significant association between ganglion cell inner-plexiform layer and SDMT 0.083 (95% CI - 0.186, 0.352) was noted. The heterogeneity was high in all correlation studies (I > 63% and p < 0.008) except for the WLG and visuospatial memory findings.
CONCLUSION
RNFL thickness is associated with cognitive processing speed, verbal learning and memory, visual learning and memory, as well as verbal fluency in PwMS. The number of studies included in the meta-analyses were limited due to non-standardized reporting.
Topics: Humans; Adult; Multiple Sclerosis; Nerve Fibers; Tomography, Optical Coherence; Retina; Cognition
PubMed: 36396812
DOI: 10.1007/s00415-022-11449-5 -
Current Eye Research Aug 2021The optical coherence tomography (OCT) has been used to evaluate the changes of retinal degeneration in patients with diabetic peripheral neuropathy (DPN) in recent... (Meta-Analysis)
Meta-Analysis
PURPOSE
The optical coherence tomography (OCT) has been used to evaluate the changes of retinal degeneration in patients with diabetic peripheral neuropathy (DPN) in recent years, but the results of previous studies were controversial. Therefore, systematic review and meta-analysis were performed to evaluate the degree of retinal neurodegeneration in DPN measured by OCT.
METHODS
A comprehensive search of PubMed, Embase, Web of Science, Scopus, China Biomedical Literature (CBM), China National Knowledge Infrastructure (CNKI), VIP, and Wanfang databases were performed to identify studies that evaluate retinal neurodegeneration in DPN by using OCT. The included studies were critically reviewed and meta-analyses were performed to evaluate differences of the OCT-derived parameters between the DPN and non-DPN patients.
RESULTS
Twelve studies were included in the final meta-analysis, involving a total of 1,807 eyes (573 in the DPN group and 1,229 in the non-DPN group). The mean peripapillary retinal nerve fiber layer (pRNFL) thickness was significantly lower in the DPN group than in the non-DPN group (weighted mean difference [WMD] = -8.37 μm; 95% CI: -11.00, -5.74). The reduction of pRNFL thickness was the most pronounced in the inferior quadrant, and the differences in the nasal and temporal quadrants were also statistically significant, with WMD (95% CI) being -4.63 μm (-7.51, -1.76) and -3.92 μm (-6.86, -0.98), respectively. Similar results were observed for macular parameters, with WMD and 95% CI being -1.0 μm (-1.5, -0.5) for macular retinal nerve fiber layer (mRNFL), -2.7 μm (-10.7, -5.3) for macular ganglion cell-inner plexiform layer (mGCIPL), and -2.2 μm (-4.4, -0.04) for macular ganglion cell complex (mGCC), respectively.
CONCLUSIONS
Patients with DPN present with significant retinal neurodegeneration, with reduced pRNFL, mRNFL, mGCIPL, and mGCC thickness. Measurements of OCT parameters may serve as a biomarker for diagnosing and monitoring DPN.
Topics: Diabetic Neuropathies; Humans; Nerve Fibers; Retinal Degeneration; Retinal Ganglion Cells; Tomography, Optical Coherence
PubMed: 33428500
DOI: 10.1080/02713683.2021.1874025 -
PloS One 2022Previous studies proposed possible applications of spectral-domain optical coherence tomography (SD-OCT) measurements in prognosticating pathologies observed in... (Meta-Analysis)
Meta-Analysis
BACKGROUND
Previous studies proposed possible applications of spectral-domain optical coherence tomography (SD-OCT) measurements in prognosticating pathologies observed in overweight/obesity, including ocular, vascular, and neurologic consequences. Therefore, we conducted a systematic review and meta-analysis to investigate the changes in the in SD-OCT measurements of the patients with higher body mass index (BMI) compared to normal weight individuals.
MATERIALS AND METHODS
We conducted a systematic search on PubMed, Scopus, and Embase. The search results underwent two-phase title/abstract and full-text screenings. We then analyzed SD-OCT measurements differences in patients with high BMI and controls, and performed meta-regression, sub-group analysis, quality assessment, and publication bias assessment. The measurements included macular thickness, cup to disc ratio, ganglion cell-inner plexiform layer (GC-IPL) and its sub-sectors, RNFL and peripapillary RNFL (pRNFL) and their sub-layers, and choroidal thickness and its sub-sectors.
RESULTS
19 studies were included in this meta-analysis accounting for 1813 individuals, 989 cases and 824 controls. There was an overall trend towards decreased thickness in high BMI patients, but only two measurements reached statistical significance: temporal retinal nerve fiber layer (RNFL) (Standardized mean difference (SMD): -0.33, 95% confidence interval (CI): -0.53 to -0.14, p<0.01) and the choroidal region 1.0 mm nasal to fovea (SMD: -0.38, 95% CI: -0.60 to -0.16, p<0.01).
CONCLUSION
Some ocular layers are thinner in patients with higher BMI than the controls. These SD-OCT measurements might correlate with adverse events related to increased body weight and have prognostic abilities. As SD-OCT is a robust, rapid and non-invasive tool, future guidelines and studies are needed to evaluate the possibility of their integration into care of the patients with obesity.
Topics: Cross-Sectional Studies; Humans; Nerve Fibers; Obesity; Retinal Ganglion Cells; Tomography, Optical Coherence
PubMed: 35476846
DOI: 10.1371/journal.pone.0267495 -
NeuroImage Oct 2016Transcranial alternating current stimulation (tACS) applies exogenous oscillatory electric field potentials to entrain neural rhythms and is used to investigate... (Review)
Review
Transcranial alternating current stimulation (tACS) applies exogenous oscillatory electric field potentials to entrain neural rhythms and is used to investigate brain-function relationships and its potential to enhance perceptual and cognitive performance. However, due to current spread tACS can cause cutaneous activation of the retina and phosphenes. Several lines of evidence suggest that retinal phosphenes are capable of inducing neural entrainment, making the contributions of central and peripheral stimulation to the effects in the brain difficult to disentangle. In this literature review, the importance of this issue is further illustrated by the fact that photic stimulation can have a direct impact on perceptual and cognitive performance. This leaves open the possibility that peripheral photic stimulation can at least in part explain the central effects that are attributed to tACS. The extent to which phosphene perception contributes to the effects of exogenous oscillatory electric fields in the brain and influence perception and cognitive performance needs to be examined to understand the working mechanisms of tACS in neurophysiology and behaviour.
Topics: Animals; Brain Mapping; Brain Waves; Evidence-Based Medicine; Evoked Potentials, Visual; Humans; Phosphenes; Photic Stimulation; Retinal Ganglion Cells; Transcranial Direct Current Stimulation; Visual Cortex; Visual Pathways; Visual Perception
PubMed: 26453929
DOI: 10.1016/j.neuroimage.2015.09.067 -
Ophthalmology and Therapy Jun 2022To evaluate the effect of COVID-19 on retinal tissues by conducting a systematic review and meta-analysis of the current literature. (Review)
Review
PURPOSE
To evaluate the effect of COVID-19 on retinal tissues by conducting a systematic review and meta-analysis of the current literature.
BACKGROUND
The novel coronavirus disease is not yet well understood. The orbit provides a window into the body's microvasculature, and as such, it is a non-invasive opportunity to analyse the systemic circulation in vivo. By analysing the current literature, we test the hypothesis that non-invasive imaging of the retina could provide insight into the effect of COVID-19 on the retinal microvasculature.
METHODS
For this systematic review and meta-analysis, we screened PubMed databases and LitCOVID19 using the search criteria: (OCTA or Optical Coherence Tomography Angiography) AND (COVID-19 or corona or SARS-CoV-2) AND (retina or fundus). Databases were searched on 11 January 2022. The primary study outcomes were studies that utilised OCTA to analyse the retina; secondary outcomes involved studies that involved other imaging modalities such as OCT, fundus photography, and fundus autofluorescence.
FINDINGS
The total number of studies included in this review was 32. Optical coherence tomography angiography scans show reduced central retinal vascular density, a thinner ganglion cell layer, a thicker retinal nerve fibre layer, and an enlarged foveal avascular zone. Optical coherence tomography scans demonstrate a thicker central macular thickness and other changes to the macula, ganglion cell, and inner nuclear layers. Many fundus photographs depicted cotton wool spots, microhaemorrhages, and vascular occlusions. Non-invasive imaging technology has demonstrated that COVID-19 can profoundly affect the retina. Therefore, there is a requirement for long-term follow-up of COVID-19 patients to assess whether the retinal damage caused by COVID-19 is reversible.
PubMed: 35488102
DOI: 10.1007/s40123-022-00509-8