Brendan L Portengen, Giorgio L Porro, Douwe Bergsma, Evert J Veldman, Saskia M Imhof, Marnix Naber
Purpose: We improve pupillary responses and diagnostic performance of flicker pupil perimetry through alterations in global and local color contrast and luminance contrast in adult patients suffering from visual field defects due to cerebral visual impairment (CVI).
Methods: Two experiments were conducted on patients with CVI (Experiment 1: 19 subjects, age M and SD 57.9 ± 14.0; Experiment 2: 16 subjects, age M and SD 57.3 ± 14.7) suffering from absolute homonymous visual field (VF) defects. We altered global color contrast (stimuli consisted of white, yellow, cyan and yellow-equiluminant-to-cyan colored wedges) in Experiment 1, and we manipulated luminance and local color contrast with bright and dark yellow and multicolor wedges in a 2-by-2 design in Experiment 2. Stimuli consecutively flickered across 44 stimulus locations within the inner 60 degrees of the VF and were offset to a contrasting (opponency colored) dark background. Pupil perimetry results were compared to standard automated perimetry (SAP) to assess diagnostic accuracy.
Results: A bright stimulus with global color contrast using yellow (p= 0.009) or white (p= 0.006) evoked strongest pupillary responses as opposed to stimuli containing local color contrast and lower brightness. Diagnostic accuracy, however, was similar across global color contrast conditions in Experiment 1 (p= 0.27) and decreased when local color contrast and less luminance contrast was introduced in Experiment 2 (p= 0.02). The bright yellow condition resulted in highest performance (AUC M = 0.85 ± 0.10, Mdn = 0.85).
Conclusion: Pupillary responses and pupil perimetry's diagnostic accuracy both benefit from high luminance contrast and global but not local color contrast.
{"title":"Effects of Stimulus Luminance, Stimulus Color and Intra-Stimulus Color Contrast on Visual Field Mapping in Neurologically Impaired Adults Using Flicker Pupil Perimetry.","authors":"Brendan L Portengen, Giorgio L Porro, Douwe Bergsma, Evert J Veldman, Saskia M Imhof, Marnix Naber","doi":"10.2147/EB.S409905","DOIUrl":"https://doi.org/10.2147/EB.S409905","url":null,"abstract":"<p><strong>Purpose: </strong>We improve pupillary responses and diagnostic performance of flicker pupil perimetry through alterations in global and local color contrast and luminance contrast in adult patients suffering from visual field defects due to cerebral visual impairment (CVI).</p><p><strong>Methods: </strong>Two experiments were conducted on patients with CVI (Experiment 1: 19 subjects, age M and SD 57.9 ± 14.0; Experiment 2: 16 subjects, age M and SD 57.3 ± 14.7) suffering from absolute homonymous visual field (VF) defects. We altered global color contrast (stimuli consisted of white, yellow, cyan and yellow-equiluminant-to-cyan colored wedges) in Experiment 1, and we manipulated luminance and local color contrast with bright and dark yellow and multicolor wedges in a 2-by-2 design in Experiment 2. Stimuli consecutively flickered across 44 stimulus locations within the inner 60 degrees of the VF and were offset to a contrasting (opponency colored) dark background. Pupil perimetry results were compared to standard automated perimetry (SAP) to assess diagnostic accuracy.</p><p><strong>Results: </strong>A bright stimulus with global color contrast using yellow (<i>p</i>= 0.009) or white (<i>p</i>= 0.006) evoked strongest pupillary responses as opposed to stimuli containing local color contrast and lower brightness. Diagnostic accuracy, however, was similar across global color contrast conditions in Experiment 1 (<i>p</i>= 0.27) and decreased when local color contrast and less luminance contrast was introduced in Experiment 2 (<i>p</i>= 0.02). The bright yellow condition resulted in highest performance (AUC M = 0.85 ± 0.10, Mdn = 0.85).</p><p><strong>Conclusion: </strong>Pupillary responses and pupil perimetry's diagnostic accuracy both benefit from high luminance contrast and global but not local color contrast.</p>","PeriodicalId":51844,"journal":{"name":"Eye and Brain","volume":"15 ","pages":"77-89"},"PeriodicalIF":4.4,"publicationDate":"2023-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://ftp.ncbi.nlm.nih.gov/pub/pmc/oa_pdf/a6/29/eb-15-77.PMC10243349.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"9603169","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Purpose: To investigate the impact of attention orientation in young myopic adults with astigmatism.
Methods: The effect of attention on foveal meridional performance and anisotropy was measured in corrected myopes with various levels of astigmatism (with-the-rule astigmatism ≤ -0.75D, Axis: 180 ± 20) using orientation-based attention. Attention was manipulated by instructing subjects to attend to either the horizontal or the vertical line of a central pre-stimulus (a pulsed cross) along separate blocks of trials. For each attention condition, meridional acuity and reaction times were measured via an annulus Gabor target situated remotely from the cross and presented at random horizontally and vertically in a two-alternative forced-choice employing two interleaved staircase procedures (one-up/one-down). Attention modulations were estimated by the difference in performance between horizontal and vertical attention.
Results: Foveal meridional performance and anisotropy were strongly affected by the orientation of attention, which appeared critical for the enhancement of reaction times and resolution. Under congruent orienting of attention, foveal meridional anisotropy was correlated with the amount of defocus for both reaction time and resolution, demonstrating greater vertical performance than horizontal performance as myopia increased. Compatible with an attentional compensation of blur through optimal orienting of attention, vertical attention enhanced reaction times compared to horizontal attention and was accompanied by an increase in overall acuity when myopia increased. Increased astigmatism was associated with smaller attention effects and asymmetry, suggesting potential deficits in the compensation of blur in astigmatic eyes.
Conclusion: Collectively, attention to orientation plays a significant role in horizontal-vertical foveal meridional anisotropy and can modulate the asymmetry of foveal perception imposed by the optics of the eye in episodes of uncorrected vision. Further work is necessary to understand how attention and refractive errors interact during visual development. These results may have practical implications for methods to enhance vision with attention training in myopic astigmats.
{"title":"Meridional Attentional Asymmetries in Astigmatic Eyes.","authors":"Elie de Lestrange-Anginieur","doi":"10.2147/EB.S407481","DOIUrl":"https://doi.org/10.2147/EB.S407481","url":null,"abstract":"<p><strong>Purpose: </strong>To investigate the impact of attention orientation in young myopic adults with astigmatism.</p><p><strong>Methods: </strong>The effect of attention on foveal meridional performance and anisotropy was measured in corrected myopes with various levels of astigmatism (with-the-rule astigmatism ≤ -0.75D, Axis: 180 ± 20) using orientation-based attention. Attention was manipulated by instructing subjects to attend to either the horizontal or the vertical line of a central pre-stimulus (a pulsed cross) along separate blocks of trials. For each attention condition, meridional acuity and reaction times were measured via an annulus Gabor target situated remotely from the cross and presented at random horizontally and vertically in a two-alternative forced-choice employing two interleaved staircase procedures (one-up/one-down). Attention modulations were estimated by the difference in performance between horizontal and vertical attention.</p><p><strong>Results: </strong>Foveal meridional performance and anisotropy were strongly affected by the orientation of attention, which appeared critical for the enhancement of reaction times and resolution. Under congruent orienting of attention, foveal meridional anisotropy was correlated with the amount of defocus for both reaction time and resolution, demonstrating greater vertical performance than horizontal performance as myopia increased. Compatible with an attentional compensation of blur through optimal orienting of attention, vertical attention enhanced reaction times compared to horizontal attention and was accompanied by an increase in overall acuity when myopia increased. Increased astigmatism was associated with smaller attention effects and asymmetry, suggesting potential deficits in the compensation of blur in astigmatic eyes.</p><p><strong>Conclusion: </strong>Collectively, attention to orientation plays a significant role in horizontal-vertical foveal meridional anisotropy and can modulate the asymmetry of foveal perception imposed by the optics of the eye in episodes of uncorrected vision. Further work is necessary to understand how attention and refractive errors interact during visual development. These results may have practical implications for methods to enhance vision with attention training in myopic astigmats.</p>","PeriodicalId":51844,"journal":{"name":"Eye and Brain","volume":"15 ","pages":"63-76"},"PeriodicalIF":4.4,"publicationDate":"2023-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://ftp.ncbi.nlm.nih.gov/pub/pmc/oa_pdf/c9/21/eb-15-63.PMC10188198.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"9483868","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Abstract Spaceflight-associated neuro-ocular syndrome (SANS) has been well documented in astronauts both during and after long-duration spaceflight and is characterized by the development of optic disc edema, globe flattening, choroidal folds, and hyperopic refractive error shifts. The exact mechanisms underlying these ophthalmic abnormalities remain unclear. New findings regarding spaceflight-associated alterations in cerebrospinal fluid spaces, specifically perivascular spaces, may shed more light on the pathophysiology of SANS. The preliminary results of a recent brain magnetic resonance imaging study show that perivascular spaces enlarge under prolonged microgravity conditions, and that the amount of fluid in perivascular spaces is linked to SANS. The exact pathophysiological mechanisms underlying enlargement of perivascular spaces in space crews are currently unclear. Here, we speculate that the dilation of perivascular spaces observed in long-duration space travelers may result from impaired cerebral venous outflow and compromised cerebrospinal fluid resorption, leading to obstruction of glymphatic perivenous outflow and increased periarterial cerebrospinal fluid inflow, respectively. Further, we provide a possible explanation for how dilated perivascular spaces can be associated with SANS. Given that enlarged perivascular spaces in space crews may be a marker of altered venous hemodynamics and reduced cerebrospinal fluid outflow, at the level of the optic nerve and eye, these disturbances may contribute to SANS. If confirmed by further studies, brain glymphatic dysfunction in space crews could potentially be considered a risk factor for the development of neurodegenerative diseases, such as Alzheimer’s disease. Furthermore, long-duration exposure to microgravity might contribute to SANS through dysregulation of the ocular glymphatic system. If prolonged spaceflight exposure causes disruption of the glymphatic systems, this might affect the ability to conduct future exploration missions, for example, to Mars. The considerations outlined in the present paper further stress the crucial need to develop effective long-term countermeasures to mitigate SANS-related physiologic changes during long-duration spaceflight.
{"title":"Does Long-Duration Exposure to Microgravity Lead to Dysregulation of the Brain and Ocular Glymphatic Systems?","authors":"P. Wostyn, T. Mader, C. Gibson, M. Nedergaard","doi":"10.2147/EB.S354710","DOIUrl":"https://doi.org/10.2147/EB.S354710","url":null,"abstract":"Abstract Spaceflight-associated neuro-ocular syndrome (SANS) has been well documented in astronauts both during and after long-duration spaceflight and is characterized by the development of optic disc edema, globe flattening, choroidal folds, and hyperopic refractive error shifts. The exact mechanisms underlying these ophthalmic abnormalities remain unclear. New findings regarding spaceflight-associated alterations in cerebrospinal fluid spaces, specifically perivascular spaces, may shed more light on the pathophysiology of SANS. The preliminary results of a recent brain magnetic resonance imaging study show that perivascular spaces enlarge under prolonged microgravity conditions, and that the amount of fluid in perivascular spaces is linked to SANS. The exact pathophysiological mechanisms underlying enlargement of perivascular spaces in space crews are currently unclear. Here, we speculate that the dilation of perivascular spaces observed in long-duration space travelers may result from impaired cerebral venous outflow and compromised cerebrospinal fluid resorption, leading to obstruction of glymphatic perivenous outflow and increased periarterial cerebrospinal fluid inflow, respectively. Further, we provide a possible explanation for how dilated perivascular spaces can be associated with SANS. Given that enlarged perivascular spaces in space crews may be a marker of altered venous hemodynamics and reduced cerebrospinal fluid outflow, at the level of the optic nerve and eye, these disturbances may contribute to SANS. If confirmed by further studies, brain glymphatic dysfunction in space crews could potentially be considered a risk factor for the development of neurodegenerative diseases, such as Alzheimer’s disease. Furthermore, long-duration exposure to microgravity might contribute to SANS through dysregulation of the ocular glymphatic system. If prolonged spaceflight exposure causes disruption of the glymphatic systems, this might affect the ability to conduct future exploration missions, for example, to Mars. The considerations outlined in the present paper further stress the crucial need to develop effective long-term countermeasures to mitigate SANS-related physiologic changes during long-duration spaceflight.","PeriodicalId":51844,"journal":{"name":"Eye and Brain","volume":"14 1","pages":"49 - 58"},"PeriodicalIF":4.4,"publicationDate":"2022-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"43062695","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
M. Santorini, T. Ferreira de Moura, S. Barraud, C. Litré, C. Brugniart, A. Denoyer, Z. Djerada, C. Arndt
Purpose To evaluate the relationship between different macular thickness parameters analyzed by SD-OCT and the central visual field (VF) evaluated with automated kinetic perimetry in a cohort of patients with pituitary tumors. Methods Data from patients with pituitary adenoma treated at Reims University Hospital between October 1st, 2017, and May 31st, 2018 were collected. All patients underwent an automated kinetic perimetry and a SD-OCT to map the ganglion cell complex (GCC), the ganglion cell layer (GCL) thickness and the retinal nerve fiber layer (RNFL) using devices from two different manufacturers. Univariate and multivariate analysis were used to evaluate the correlation between the area of central VF in square degrees (deg2) and the SD-OCT parameters (μm). Results Eighty-eight eyes were included in the analysis. All the thickness parameters measured in SD-OCT decreased with the visual field alteration. The best correlation was observed between superior thickness parameters (GCC, GCL) and the inferior central visual field. The most pertinent predictive factors for visual field loss were the inferior central GCL and the nasal RNFL (both AUC=0.775) with a sensitivity respectively of 86% and 70%. Conclusion This study suggests that both GCC, GCL thickness parameters could be reliable predictors of central visual field impairment in patients with pituitary tumors. There was no significative difference between both devices.
{"title":"Comparative Evaluation of Two SD-OCT Macular Parameters (GCC, GCL) and RNFL in Chiasmal Compression","authors":"M. Santorini, T. Ferreira de Moura, S. Barraud, C. Litré, C. Brugniart, A. Denoyer, Z. Djerada, C. Arndt","doi":"10.2147/EB.S337333","DOIUrl":"https://doi.org/10.2147/EB.S337333","url":null,"abstract":"Purpose To evaluate the relationship between different macular thickness parameters analyzed by SD-OCT and the central visual field (VF) evaluated with automated kinetic perimetry in a cohort of patients with pituitary tumors. Methods Data from patients with pituitary adenoma treated at Reims University Hospital between October 1st, 2017, and May 31st, 2018 were collected. All patients underwent an automated kinetic perimetry and a SD-OCT to map the ganglion cell complex (GCC), the ganglion cell layer (GCL) thickness and the retinal nerve fiber layer (RNFL) using devices from two different manufacturers. Univariate and multivariate analysis were used to evaluate the correlation between the area of central VF in square degrees (deg2) and the SD-OCT parameters (μm). Results Eighty-eight eyes were included in the analysis. All the thickness parameters measured in SD-OCT decreased with the visual field alteration. The best correlation was observed between superior thickness parameters (GCC, GCL) and the inferior central visual field. The most pertinent predictive factors for visual field loss were the inferior central GCL and the nasal RNFL (both AUC=0.775) with a sensitivity respectively of 86% and 70%. Conclusion This study suggests that both GCC, GCL thickness parameters could be reliable predictors of central visual field impairment in patients with pituitary tumors. There was no significative difference between both devices.","PeriodicalId":51844,"journal":{"name":"Eye and Brain","volume":"14 1","pages":"35 - 48"},"PeriodicalIF":4.4,"publicationDate":"2022-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"68359890","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Manzar Ashtari, Mikhail Lipin, Michelle Duong, Gui-Shuang Ying, Yinxi Yu, Albert Maguire, Jean Bennett
Introduction: Previous works on experience-dependent brain plasticity have been limited to the cortical structures, overlooking subcortical visual structures such as the lateral geniculate nucleus (LGN). Animal studies have shown substantial experience dependent plasticity and using fMRI, human studies have demonstrated similar properties in patients with cataract surgery. However, in neither animal nor human studies LGN has not been directly assessed, mainly due to its small size, tissue heterogeneity, low contrast/noise ratio, and low spatial resolution.
Methods: Utilizing a new algorithm that markedly improves the LGN visibility, LGN was evaluated in a group of low vision patients before and after retinal intervention to reinstate vision and normal sighted matched controls.
Results: Between and within groups comparisons showed that patients had significantly smaller left (p< 0.0001) and right (p < 0.00002) LGN volumes at baseline as compared to the one-year follow-up volumes. The same baseline and one year comparison in controls was not significant. Significant positive correlations were observed between the incremental volume increase after gene therapy of the left LGN and the incremental increase in the right (r = 0.71, p < 0.02) and left (r = 0.72, p = 0.018) visual fields. Incremental volume increase of the right LGN also showed a similar positive slope but did not reach significance.
Discussion: These results show that despite significantly less volume at baseline, retinal gene therapy promotes robust expansion and increase in LGN volume. Reinstating vision may have facilitated the establishment of new connections between the retina and the LGN and/or unmasking of the dormant connections. The exact trajectory of the structural changes taking place in LGN is unclear but our data shows that even after years of low vision, the LGN in RPE65 patients has the potential for plasticity and expansion to a nearly normal volume one year after gene therapy administration.
以往关于经验依赖大脑可塑性的研究仅限于皮层结构,忽视了皮层下的视觉结构,如外侧膝状核(LGN)。动物研究已经显示了大量的经验依赖可塑性,使用功能磁共振成像,人类研究已经在白内障手术患者中证明了类似的特性。然而,在动物和人类研究中,LGN都没有被直接评估,主要是由于其体积小、组织异质性、低对比度/噪声比和低空间分辨率。方法:采用一种明显提高LGN可见度的新算法,对一组低视力患者进行视网膜干预恢复视力前后的LGN进行评估,并与正常视力对照进行比较。结果:组间和组内比较显示,基线时患者左侧LGN体积(p< 0.0001)和右侧LGN体积(p< 0.00002)明显小于1年随访时的体积。相同的基线和对照组的一年比较无显著性。左侧LGN基因治疗后体积增量与右侧视野(r = 0.71, p < 0.02)、左侧视野(r = 0.72, p = 0.018)体积增量呈显著正相关。右侧LGN的增量体积增加也呈现类似的正斜率,但没有达到显著性。讨论:这些结果表明,尽管在基线时体积明显减少,视网膜基因治疗促进了LGN的强劲扩张和体积的增加。恢复视力可能有助于在视网膜和LGN之间建立新的连接和/或揭开休眠连接的面纱。LGN发生结构变化的确切轨迹尚不清楚,但我们的数据显示,即使经过多年的低视力,RPE65患者的LGN在接受基因治疗一年后仍具有可塑性和扩大到接近正常体积的潜力。
{"title":"Neuroplasticity of the Lateral Geniculate Nucleus in Response to Retinal Gene Therapy in a Group of Patients with <i>RPE65</i> Mutations.","authors":"Manzar Ashtari, Mikhail Lipin, Michelle Duong, Gui-Shuang Ying, Yinxi Yu, Albert Maguire, Jean Bennett","doi":"10.2147/EB.S377275","DOIUrl":"https://doi.org/10.2147/EB.S377275","url":null,"abstract":"<p><strong>Introduction: </strong>Previous works on experience-dependent brain plasticity have been limited to the cortical structures, overlooking subcortical visual structures such as the lateral geniculate nucleus (LGN). Animal studies have shown substantial experience dependent plasticity and using fMRI, human studies have demonstrated similar properties in patients with cataract surgery. However, in neither animal nor human studies LGN has not been directly assessed, mainly due to its small size, tissue heterogeneity, low contrast/noise ratio, and low spatial resolution.</p><p><strong>Methods: </strong>Utilizing a new algorithm that markedly improves the LGN visibility, LGN was evaluated in a group of low vision patients before and after retinal intervention to reinstate vision and normal sighted matched controls.</p><p><strong>Results: </strong>Between and within groups comparisons showed that patients had significantly smaller left (p< 0.0001) and right (p < 0.00002) LGN volumes at baseline as compared to the one-year follow-up volumes. The same baseline and one year comparison in controls was not significant. Significant positive correlations were observed between the incremental volume increase after gene therapy of the left LGN and the incremental increase in the right (r = 0.71, p < 0.02) and left (r = 0.72, p = 0.018) visual fields. Incremental volume increase of the right LGN also showed a similar positive slope but did not reach significance.</p><p><strong>Discussion: </strong>These results show that despite significantly less volume at baseline, retinal gene therapy promotes robust expansion and increase in LGN volume. Reinstating vision may have facilitated the establishment of new connections between the retina and the LGN and/or unmasking of the dormant connections. The exact trajectory of the structural changes taking place in LGN is unclear but our data shows that even after years of low vision, the LGN in RPE65 patients has the potential for plasticity and expansion to a nearly normal volume one year after gene therapy administration.</p>","PeriodicalId":51844,"journal":{"name":"Eye and Brain","volume":"14 ","pages":"137-147"},"PeriodicalIF":4.4,"publicationDate":"2022-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://ftp.ncbi.nlm.nih.gov/pub/pmc/oa_pdf/39/70/eb-14-137.PMC9749418.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"9489794","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Introduction: Diabetic patients routinely have high levels of high mobility group box 1 (HMGB1) protein in their plasma, vitreous and ocular membranes, which is strongly correlated with subclinical chronic inflammation in the eye. Our previous work has suggested that high HMGB1 in diabetes plays a role in retinal inflammation and angiogenesis, but its role in the optic nerve damage is unclear. Therefore, our goal is to examine the role of HMGB1 in optic nerve damage in diabetes.
Methods: Gene expression of HMGB1 was quantified in the optic nerve from streptozotocin-induced diabetic mice by qRT-PCR, and their protein expressions by Western blot analysis and immunofluorescence staining. Using immunohistochemical technique, expression of reactive astrogliosis (indicator of neuroinflammation) and nerve demyelination/damage were determined by quantifying glial fibrillary acid protein (GFAP) and myelin basic protein (MBP), respectively. The role of HMGB1 in the optic nerve damage and alteration visual pathways was confirmed in mice receiving glycyrrhizin, a HMGB1 inhibitor. Similar parameters were measured in the optic nerve from human donors with diabetes.
Results: Compared to normal mice, diabetic mice exhibited increased levels of HMGB1, higher GFAP expression, and decreased MBP in the optic nerve. Double immunofluorescence microscopy revealed that diabetes induced increased HMGB1 immunoreactivities were significantly colocalized with GFAP in the optic nerve. Glycyrrhizin supplementation effectively reduced HMGB1 and maintained normal axonal myelination and visual conduction. Results from mice optic nerve confirmed the results obtained from human donors with diabetes.
Discussions: Thus, diabetes-induced HMGB1 upregulation promotes optic nerve demyelination and inflammation. The regulation of HMGB1 activation has potential to protect optic nerve damage and the abnormalities of visual pathways in diabetic patients.
{"title":"Involvement of High Mobility Group Box 1 Protein in Optic Nerve Damage in Diabetes.","authors":"Ghulam Mohammad, Renu A Kowluru","doi":"10.2147/EB.S352730","DOIUrl":"https://doi.org/10.2147/EB.S352730","url":null,"abstract":"<p><strong>Introduction: </strong>Diabetic patients routinely have high levels of high mobility group box 1 (HMGB1) protein in their plasma, vitreous and ocular membranes, which is strongly correlated with subclinical chronic inflammation in the eye. Our previous work has suggested that high HMGB1 in diabetes plays a role in retinal inflammation and angiogenesis, but its role in the optic nerve damage is unclear. Therefore, our goal is to examine the role of HMGB1 in optic nerve damage in diabetes.</p><p><strong>Methods: </strong>Gene expression of HMGB1 was quantified in the optic nerve from streptozotocin-induced diabetic mice by qRT-PCR, and their protein expressions by Western blot analysis and immunofluorescence staining. Using immunohistochemical technique, expression of reactive astrogliosis (indicator of neuroinflammation) and nerve demyelination/damage were determined by quantifying glial fibrillary acid protein (GFAP) and myelin basic protein (MBP), respectively. The role of HMGB1 in the optic nerve damage and alteration visual pathways was confirmed in mice receiving glycyrrhizin, a HMGB1 inhibitor. Similar parameters were measured in the optic nerve from human donors with diabetes.</p><p><strong>Results: </strong>Compared to normal mice, diabetic mice exhibited increased levels of HMGB1, higher GFAP expression, and decreased MBP in the optic nerve. Double immunofluorescence microscopy revealed that diabetes induced increased HMGB1 immunoreactivities were significantly colocalized with GFAP in the optic nerve. Glycyrrhizin supplementation effectively reduced HMGB1 and maintained normal axonal myelination and visual conduction. Results from mice optic nerve confirmed the results obtained from human donors with diabetes.</p><p><strong>Discussions: </strong>Thus, diabetes-induced HMGB1 upregulation promotes optic nerve demyelination and inflammation. The regulation of HMGB1 activation has potential to protect optic nerve damage and the abnormalities of visual pathways in diabetic patients.</p>","PeriodicalId":51844,"journal":{"name":"Eye and Brain","volume":"14 ","pages":"59-69"},"PeriodicalIF":4.4,"publicationDate":"2022-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://ftp.ncbi.nlm.nih.gov/pub/pmc/oa_pdf/66/39/eb-14-59.PMC9109986.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"9756010","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2021-12-14eCollection Date: 2021-01-01DOI: 10.2147/EB.S272343
Ethan Waisberg, Jonathan A Micieli
Optic nerve cupping or enlargement of the cup-to-disc ratio is widely recognized as a feature of glaucoma, however it may also occur in non-glaucomatous optic neuropathies. The most well-recognized non-glaucomatous optic neuropathies that cause cupping include compressive optic neuropathies, arteritic anterior ischemic optic neuropathies, hereditary optic neuropathies, and optic neuritis. Cupping is thought to consist of two main components: prelaminar and laminar thinning. The former is a shallow form of cupping and related to loss of retinal ganglion cells, whereas the latter involves damage to the lamina cribrosa and peripapillary scleral connective tissue. Differentiating glaucomatous and non-glaucomatous optic nerve cupping remains challenging even for experienced observers. Classically, the optic nerve in non-glaucomatous causes has pallor of the neuroretinal rim, but the optic nerve should not be examined in isolation. The patient's medical history, history of presenting illness, visual function (visual acuity, color vision and visual field testing) and ocular examination also need to be considered. Ancillary testing such as optical coherence tomography of the retinal nerve fiber layer and ganglion cell layer-inner plexiform layer may also be helpful in localizing the disease. In this review, we review the non-glaucomatous causes of cupping and provide an approach to evaluating a patient that presents with an enlarged cup-to-disc ratio.
{"title":"Neuro-Ophthalmological Optic Nerve Cupping: An Overview.","authors":"Ethan Waisberg, Jonathan A Micieli","doi":"10.2147/EB.S272343","DOIUrl":"https://doi.org/10.2147/EB.S272343","url":null,"abstract":"<p><p>Optic nerve cupping or enlargement of the cup-to-disc ratio is widely recognized as a feature of glaucoma, however it may also occur in non-glaucomatous optic neuropathies. The most well-recognized non-glaucomatous optic neuropathies that cause cupping include compressive optic neuropathies, arteritic anterior ischemic optic neuropathies, hereditary optic neuropathies, and optic neuritis. Cupping is thought to consist of two main components: prelaminar and laminar thinning. The former is a shallow form of cupping and related to loss of retinal ganglion cells, whereas the latter involves damage to the lamina cribrosa and peripapillary scleral connective tissue. Differentiating glaucomatous and non-glaucomatous optic nerve cupping remains challenging even for experienced observers. Classically, the optic nerve in non-glaucomatous causes has pallor of the neuroretinal rim, but the optic nerve should not be examined in isolation. The patient's medical history, history of presenting illness, visual function (visual acuity, color vision and visual field testing) and ocular examination also need to be considered. Ancillary testing such as optical coherence tomography of the retinal nerve fiber layer and ganglion cell layer-inner plexiform layer may also be helpful in localizing the disease. In this review, we review the non-glaucomatous causes of cupping and provide an approach to evaluating a patient that presents with an enlarged cup-to-disc ratio.</p>","PeriodicalId":51844,"journal":{"name":"Eye and Brain","volume":"13 ","pages":"255-268"},"PeriodicalIF":4.4,"publicationDate":"2021-12-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://ftp.ncbi.nlm.nih.gov/pub/pmc/oa_pdf/66/ad/eb-13-255.PMC8684388.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"39607542","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2021-10-01eCollection Date: 2021-01-01DOI: 10.2147/EB.S272326
Stephanie J Chiu, Simon J Hickman, Irene M Pepper, Jennifer H Y Tan, John Yianni, Joanna M Jefferis
Vestibular schwannomas (VSs), also called acoustic neuromas, are benign intracranial neoplasms of the vestibulocochlear (VIII) cranial nerve. Management options include "wait-and-scan," stereotactic radiosurgery and surgical resection. Due to the proximity of the VIII nerve to the facial (VII) nerve in the cerebello-pontine angle, the VII nerve is particularly vulnerable to the effects of surgical resection. This can result in poor eye closure, lagophthalmos and resultant corneal exposure post VS resection. Additionally, compression from the tumor or resection can cause trigeminal (V) nerve damage and a desensate cornea. The combination of an exposed and desensate cornea puts the eye at risk of serious ocular complications including persistent epithelial defects, corneal ulceration, corneal vascularization, corneal melting and potential perforation. The abducens (VI) nerve can be affected by a large intracranial VS causing raised intracranial pressure (a false localizing sign) or as a result of damage to the VI nerve at the time of resection. Other types of neurogenic strabismus are rare and typically transient. Contralaterally beating nystagmus as a consequence of vestibular dysfunction is common post-operatively. This generally settles to pre-operative levels as central compensation occurs. Ipsilaterally beating nystagmus post-operatively should prompt investigation for post-operative cerebrovascular complications. Papilledema (and subsequent optic atrophy) can occur as a result of a large VS causing raised intracranial pressure. Where papilledema follows surgical resection of a VS, it can indicate that cerebral venous sinus thrombosis has occurred. Poor visual function following VS resection can result as a combination of all these potential complications and is more likely with larger tumors.
{"title":"Neuro-Ophthalmic Complications of Vestibular Schwannoma Resection: Current Perspectives.","authors":"Stephanie J Chiu, Simon J Hickman, Irene M Pepper, Jennifer H Y Tan, John Yianni, Joanna M Jefferis","doi":"10.2147/EB.S272326","DOIUrl":"https://doi.org/10.2147/EB.S272326","url":null,"abstract":"<p><p>Vestibular schwannomas (VSs), also called acoustic neuromas, are benign intracranial neoplasms of the vestibulocochlear (VIII) cranial nerve. Management options include \"wait-and-scan,\" stereotactic radiosurgery and surgical resection. Due to the proximity of the VIII nerve to the facial (VII) nerve in the cerebello-pontine angle, the VII nerve is particularly vulnerable to the effects of surgical resection. This can result in poor eye closure, lagophthalmos and resultant corneal exposure post VS resection. Additionally, compression from the tumor or resection can cause trigeminal (V) nerve damage and a desensate cornea. The combination of an exposed and desensate cornea puts the eye at risk of serious ocular complications including persistent epithelial defects, corneal ulceration, corneal vascularization, corneal melting and potential perforation. The abducens (VI) nerve can be affected by a large intracranial VS causing raised intracranial pressure (a false localizing sign) or as a result of damage to the VI nerve at the time of resection. Other types of neurogenic strabismus are rare and typically transient. Contralaterally beating nystagmus as a consequence of vestibular dysfunction is common post-operatively. This generally settles to pre-operative levels as central compensation occurs. Ipsilaterally beating nystagmus post-operatively should prompt investigation for post-operative cerebrovascular complications. Papilledema (and subsequent optic atrophy) can occur as a result of a large VS causing raised intracranial pressure. Where papilledema follows surgical resection of a VS, it can indicate that cerebral venous sinus thrombosis has occurred. Poor visual function following VS resection can result as a combination of all these potential complications and is more likely with larger tumors.</p>","PeriodicalId":51844,"journal":{"name":"Eye and Brain","volume":"13 ","pages":"241-253"},"PeriodicalIF":4.4,"publicationDate":"2021-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://ftp.ncbi.nlm.nih.gov/pub/pmc/oa_pdf/eb/24/eb-13-241.PMC8491867.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"39495188","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2021-09-24eCollection Date: 2021-01-01DOI: 10.2147/EB.S338935
David Fleischman, Hanspeter E Killer
1Department of Ophthalmology, University of North Carolina at Chapel Hill, Chapel Hill, NC, USA; 2Department of Ophthalmology, Kantonsspital Aarau, Aarau, Switzerland Dear editor We took interest in the recent article by Qian Wang and colleagues, “Prevalence of Retinal Vein Occlusions and Estimated Cerebrospinal Fluid Pressure: The Kailuan Eye Study.” We agree with the authors that CSF pressure, in particular the perioptic subarachnoid space pressure, is likely important in the development of many cases of retinal vein occlusions. However, we were troubled by the methodology employed by the study team. While we appreciate the mention of our study that had found that formulae used to predict CSFP derived from clinical data were unable to accurately estimate CSF pressures, we were surprised that this formula was nonetheless used in the current study. Even more troubling is that the reference given for the justification of the formula, “eCSFP [mm Hg] = 0.44 * BMI [kg/m2] + 0.16 * DBP [mm Hg] – 0.18 * Age [years],” does not in fact explain its derivation. The Xie study from Critical Care used patientspecific anatomic measurements derived from MRI data in order to estimate CSFP, an important factor that has been excluded from the current study’s equation. CSF pressure is not static. It varies over time as a function of the production and resorption rate of CSF and body posture. A formula that is derived top down from preexisting data (such as BMI and DBP) is far from representing the complexity of CSF dynamics, including CSF pressure. Neither is CSF pressure and composition homogeneous throughout all CSF-containing spaces. Further, even if it could reflect the appropriate CSF pressure in the lumbar spine region, it is purely speculative to assume that this measurement could be extrapolated to the pressure within the subarachnoid space of the optic nerve. Several studies in patients with papilledema as well as normal tension glaucoma demonstrated “comparted” optic nerve sheaths, a finding that cautions even the assumption that the pressure measured at the lumber site reflects the pressure in the perioptic space. Thus, to assume that all CSF spaces connect via a linear continuum can be quite misleading. In conclusion, we are strongly supportive of research that will further the understanding of the cerebrospinal fluid’s role in ophthalmic disease. However, bad data are worse than no data. We would have expected that the limitations of such a study should have been clearly explained to the reader who may not be familiar with this complex topic, and we discourage the use of unvalidated formulae for CSF and ophthalmic research. Correspondence: David Fleischman Department of Ophthalmology, University of North Carolina at Chapel Hill, 5126 Bioinformatics Bldg #7040, Chapel Hill, NC, 27599-7040, USA Tel +1 919 259-9336 Fax +1 919 966-1908 Email david8fleischman@gmail.com
{"title":"Studies Utilizing Current Estimated CSF Pressure Equations Should Not Be Conducted and Published [Letter].","authors":"David Fleischman, Hanspeter E Killer","doi":"10.2147/EB.S338935","DOIUrl":"https://doi.org/10.2147/EB.S338935","url":null,"abstract":"1Department of Ophthalmology, University of North Carolina at Chapel Hill, Chapel Hill, NC, USA; 2Department of Ophthalmology, Kantonsspital Aarau, Aarau, Switzerland Dear editor We took interest in the recent article by Qian Wang and colleagues, “Prevalence of Retinal Vein Occlusions and Estimated Cerebrospinal Fluid Pressure: The Kailuan Eye Study.” We agree with the authors that CSF pressure, in particular the perioptic subarachnoid space pressure, is likely important in the development of many cases of retinal vein occlusions. However, we were troubled by the methodology employed by the study team. While we appreciate the mention of our study that had found that formulae used to predict CSFP derived from clinical data were unable to accurately estimate CSF pressures, we were surprised that this formula was nonetheless used in the current study. Even more troubling is that the reference given for the justification of the formula, “eCSFP [mm Hg] = 0.44 * BMI [kg/m2] + 0.16 * DBP [mm Hg] – 0.18 * Age [years],” does not in fact explain its derivation. The Xie study from Critical Care used patientspecific anatomic measurements derived from MRI data in order to estimate CSFP, an important factor that has been excluded from the current study’s equation. CSF pressure is not static. It varies over time as a function of the production and resorption rate of CSF and body posture. A formula that is derived top down from preexisting data (such as BMI and DBP) is far from representing the complexity of CSF dynamics, including CSF pressure. Neither is CSF pressure and composition homogeneous throughout all CSF-containing spaces. Further, even if it could reflect the appropriate CSF pressure in the lumbar spine region, it is purely speculative to assume that this measurement could be extrapolated to the pressure within the subarachnoid space of the optic nerve. Several studies in patients with papilledema as well as normal tension glaucoma demonstrated “comparted” optic nerve sheaths, a finding that cautions even the assumption that the pressure measured at the lumber site reflects the pressure in the perioptic space. Thus, to assume that all CSF spaces connect via a linear continuum can be quite misleading. In conclusion, we are strongly supportive of research that will further the understanding of the cerebrospinal fluid’s role in ophthalmic disease. However, bad data are worse than no data. We would have expected that the limitations of such a study should have been clearly explained to the reader who may not be familiar with this complex topic, and we discourage the use of unvalidated formulae for CSF and ophthalmic research. Correspondence: David Fleischman Department of Ophthalmology, University of North Carolina at Chapel Hill, 5126 Bioinformatics Bldg #7040, Chapel Hill, NC, 27599-7040, USA Tel +1 919 259-9336 Fax +1 919 966-1908 Email david8fleischman@gmail.com","PeriodicalId":51844,"journal":{"name":"Eye and Brain","volume":"13 ","pages":"239-240"},"PeriodicalIF":4.4,"publicationDate":"2021-09-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://ftp.ncbi.nlm.nih.gov/pub/pmc/oa_pdf/e2/e2/eb-13-239.PMC8478159.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"39474085","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2021-08-29eCollection Date: 2021-01-01DOI: 10.2147/EB.S315403
Supharat Jariyakosol, Patcharaporn Jaru-Ampornpan, Anita Manassakorn, Rath Itthipanichpong, Parima Hirunwiwatkul, Visanee Tantisevi, Thanapong Somkijrungroj, Prin Rojanapongpun
Purpose: To assess the diagnostic accuracy of visual field results generated by the newly developed software (CU-VF) and the standard automated perimetry (SAP) for detecting hemianopia.
Patients and methods: Forty-three subjects with hemianopia and 33 controls were tested with the CU-VF software on a personal computer and SAP. Hemianopia was defined as the presence of a hemianopic field respecting the vertical meridian on SAP with the corresponding neuroimaging pathology as evaluated by 2 neuro-ophthalmologists. Results of CU-VF were independently evaluated by 2 neuro-ophthalmologists, 1 general ophthalmologist, and 1 general practitioner in terms of the presence of hemianopia. Sensitivity, specificity, and kappa coefficient for inter-observer reliability were calculated. Satisfaction and ease of use were evaluated with a visual analog-scale questionnaire and analyzed using paired t-test.
Results: The sensitivity (95% CI) and specificity (95% CI) of the CU-VF to detect hemianopia was 74.42% (58.53-85.96) and 93.94% (78.38-99.94). Kappa coefficient between neuro-ophthalmologists versus general ophthalmologist and general practitioner were 0.71 and 0.84, respectively. The mean (SD) test duration was 2.25 (0.002) minutes for the CU-VF and 5.38 (1.34) minutes for SAP (p < 0.001). Subjects reported significantly higher satisfaction and comfort using the CU-VF software compared to SAP.
Conclusion: The CU-VF screening software showed good validity and reliability to detect hemianopia, with shorter test duration and higher subject satisfaction compared to SAP.
{"title":"Sensitivity and Specificity of New Visual Field Screening Software for Diagnosing Hemianopia.","authors":"Supharat Jariyakosol, Patcharaporn Jaru-Ampornpan, Anita Manassakorn, Rath Itthipanichpong, Parima Hirunwiwatkul, Visanee Tantisevi, Thanapong Somkijrungroj, Prin Rojanapongpun","doi":"10.2147/EB.S315403","DOIUrl":"https://doi.org/10.2147/EB.S315403","url":null,"abstract":"<p><strong>Purpose: </strong>To assess the diagnostic accuracy of visual field results generated by the newly developed software (CU-VF) and the standard automated perimetry (SAP) for detecting hemianopia.</p><p><strong>Patients and methods: </strong>Forty-three subjects with hemianopia and 33 controls were tested with the CU-VF software on a personal computer and SAP. Hemianopia was defined as the presence of a hemianopic field respecting the vertical meridian on SAP with the corresponding neuroimaging pathology as evaluated by 2 neuro-ophthalmologists. Results of CU-VF were independently evaluated by 2 neuro-ophthalmologists, 1 general ophthalmologist, and 1 general practitioner in terms of the presence of hemianopia. Sensitivity, specificity, and kappa coefficient for inter-observer reliability were calculated. Satisfaction and ease of use were evaluated with a visual analog-scale questionnaire and analyzed using paired <i>t</i>-test.</p><p><strong>Results: </strong>The sensitivity (95% CI) and specificity (95% CI) of the CU-VF to detect hemianopia was 74.42% (58.53-85.96) and 93.94% (78.38-99.94). Kappa coefficient between neuro-ophthalmologists versus general ophthalmologist and general practitioner were 0.71 and 0.84, respectively. The mean (SD) test duration was 2.25 (0.002) minutes for the CU-VF and 5.38 (1.34) minutes for SAP (p < 0.001). Subjects reported significantly higher satisfaction and comfort using the CU-VF software compared to SAP.</p><p><strong>Conclusion: </strong>The CU-VF screening software showed good validity and reliability to detect hemianopia, with shorter test duration and higher subject satisfaction compared to SAP.</p>","PeriodicalId":51844,"journal":{"name":"Eye and Brain","volume":"13 ","pages":"231-238"},"PeriodicalIF":4.4,"publicationDate":"2021-08-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://ftp.ncbi.nlm.nih.gov/pub/pmc/oa_pdf/99/a8/eb-13-231.PMC8412821.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"39409406","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}