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Biomedical subjects

Frederick L Ferris

Publications and source records attributed to Frederick L Ferris.

At least 19 recordsLinked to original sources
PubMed2006

Vitamin E in the treatment of uveitis-associated macular edema.

PURPOSE: To investigate whether high-dose alpha-tocopherol (vitamin E) could reduce vision loss and retinal thickening associated with uveitis-associated cystoid macular edema. DESIGN: A double-masked, randomized study. METHODS: Uveitis patients with macular edema seen at the NIH were randomized and received either 1600 IU/day of vitamin E or placebo for 4 months. Visual acuity and retinal thickening were collected for the efficacy and the safety of the high dose of vitamin E. RESULTS: Changes in visual acuity and retinal thickening. CONCLUSIONS: Four-month oral supplementation with 1600 IU/d of vitamin E had no apparent effect on uveitis-associated macular edema or visual acuity in this small study.

Adult↗
PubMed2006

Centrum use and progression of age-related cataract in the Age-Related Eye Disease Study: a propensity score approach. AREDS report No. 21.

PURPOSE: To evaluate the effect of the multivitamin Centrum on the development and progression of age-related lens opacities. DESIGN: Clinic-based prospective cohort study. PARTICIPANTS: Four thousand five hundred ninety individuals with at least one natural lens and photographic follow-up (median, 6.3 years) were assessed for development or progression of lens opacities. MAIN OUTCOME MEASURES: Progression of "any" lens opacity or type-specific opacity was ascertained from lens photographs taken at baseline and at annual visits beginning at year 2. METHODS: The Age-Related Eye Disease Study (AREDS) showed no statistically significant effect of a high-dose antioxidant formulation on progression of lens opacities. Centrum also was provided to approximately two thirds of the study participants. Because Centrum use was elective, a logistic regression model of baseline characteristics was used to generate a propensity score for Centrum use. Repeated-measures logistic regression, adjusted for propensity score and other covariates, was used to evaluate associations of Centrum use and lens opacity. RESULTS: Centrum use, adjusted for propensity score and other covariates, was associated with a reduction in "any" lens opacity progression (odds ratio [OR] = 0.84, 95% confidence interval [CI] = 0.72-0.98, P = 0.025). Results for individual lens opacity types suggested that Centrum use was protective for nuclear opacity events (OR = 0.75, 95% CI = 0.61-0.91, P = 0.004). CONCLUSION: Observational data from the AREDS and other studies suggest that use of a multivitamin may delay the progression of lens opacities. A National Eye Institute-sponsored clinical trial scheduled for completion in 2007 will provide additional data on Centrum use and cataract development.

Aged↗
PubMed2006

Anatomical and visual results of vitreoretinal surgery for stage 5 retinopathy of prematurity.

PURPOSE: To provide a historical perspective on outcomes of surgery for infants with stage 5 retinopathy of prematurity (ROP) as performed by a single surgeon over a 24-year period. DESIGN: Retrospective observational cohort study. METHODS SETTING: Clinical practice of the Charles Retina Institute. PATIENTS: The 601 infants with stage 5 ROP in at least one eye who were referred for surgery between 1977 and 2001. Charts were reviewed for demographic data and postoperative anatomical and visual acuity outcomes in eyes that underwent surgery. MAIN OUTCOME MEASURES: The postoperative anatomical status of the retina and visual function were assessed after surgery. Anatomical outcome was categorized as success (macula attached), partial success (macula detached), failure (total retinal detachment), or lost eye (opaque cornea, secluded pupil, or phthisis). Visual function was classified as>20/200, 20/200-5/200, hand movement, light perception, or no light perception. Multivariable logistic regression was used to explore relationships between outcomes and baseline characteristics. RESULTS: Only a minority of eyes had prior cryotherapy (15%) or laser photocoagulation (7%) therapy. The mean follow-up was 44 months for the 956 eyes treated surgically. The 608 eyes with available follow-up data were classified as follows: 28% success, 5% partial success, 55% failure, and 11% lost eye. Visual function of light perception or better was achieved in 74% of the 183 eyes with data on visual acuity. Controlling for other baseline factors, early postpartum age at the time of surgery was a statistically significant predictor of failure/lost eye (OR=2.08, 95% CI 1.09-3.97) and no light perception (OR=5.13, 95% CI 1.45-18.14). Surgery for stage 5 ROP on the fellow eye was also a predictor of failure/lost eye (OR=2.38, 95% CI 1.39-4.08). CONCLUSIONS: Surgery resulted in anatomical success for approximately one third of infant eyes with stage 5 ROP, and only a minority of eyes (8 of 183) achieved visual acuity better than 5/200. However, some initially successfully attached retinas redetached. Although this study is limited by follow-up and may represent a group of patients with a more vascularly active disease state due to the low proportion of patients with prior peripheral ablation, this cohort of infants provides results against which future interventions may be compared.

Birth Weight↗
PubMed2006

Dose-ranging study of lutein supplementation in persons aged 60 years or older.

PURPOSE: To examine the dose-response relationship between oral lutein supplementation and serum lutein concentrations in persons aged 60 years and older, with or without age-related macular degeneration (AMD). METHODS: Forty-five participants with no AMD, large drusen, or advanced AMD, were randomized to receive one of three doses (2.5, 5, or 10 mg) of lutein for 6 months and to be observed for 6 additional months after the cessation of lutein supplementation. RESULTS: The mean age of the participants (33 women) was 71 years (range: 60-91). The serum lutein concentrations of each dose group were similar before supplementation, increased at 1 month, and peaked by 3 months. Median serum concentrations of the 2.5-, 5-, and 10-mg groups from baseline to month 6 increased from 18.7 to 35.1 microg/dL (2-fold increase), from 17.8 to 59.2 microg/dL (2.9-fold increase), and from 15.1 to 66.8 microg/dL (4-fold increase), respectively (all P < 0.001). The increases in lutein serum concentrations did not vary with AMD disease severity (P = 0.98). No toxicity was observed with any dose of lutein. No significant changes were detected in visual acuity or visual field tests. CONCLUSIONS: Increasing doses of lutein supplements significantly increased the serum levels of lutein and zeaxanthin, and doses up to 10 mg were safely administered. A long-term large clinical trial is necessary to investigate the safety and efficacy of lutein in reducing the risk of the development of advanced AMD.

Administration, Oral↗
PubMed2006

The effect of lutein and zeaxanthin supplementation on metabolites of these carotenoids in the serum of persons aged 60 or older.

PURPOSE: To investigate the effect of lutein supplementation at doses of 2.5, 5.0, and 10 mg/d for 6 months on distribution of these carotenoids and their metabolites in the serum of elderly human subjects, with and without age-related macular degeneration. To determine whether supplementation with lutein can interact with the serum levels of other dietary carotenoids, retinol, and alpha-tocopherol. METHODS: Forty-five subjects received daily supplements of lutein (containing 5% zeaxanthin) for 6 months and were followed up for another 6 months after supplementation. Blood was collected at various intervals and lutein, zeaxanthin, and their metabolites in the sera were quantified by normal-phase high-performance liquid chromatography (HPLC)-UV/visible detection. Other dietary carotenoids, retinol, and alpha-tocopherol were identified and quantified on a C18 reversed phase HPLC column. RESULTS: After 6 months of supplementation with 10 mg of lutein, the increases in the mean serum levels from baseline were: 210 to 1000 nM/L (P < 0.0001) for lutein and 56 to 95 nM/L (P < 0.0001) for zeaxanthin. Similarly, the mean concentrations (nM/L) of carotenoid metabolites increased from 49 to 98 (P < 0.0001) for 3-hydroxy-beta,epsilon-caroten-3'-one (3'-oxolutein); 31 to 80 (P < 0.0001) for 3'-hydroxy-epsilon,epsilon-caroten-3-one; and 19 to 25 (P < 0.0001) for epsilon,epsilon-carotene-3,3'-dione. The serum levels of these carotenoids gradually decline within 6 months after supplementation. CONCLUSIONS: The increase in the serum levels of lutein/zeaxanthin correlates with increases in the serum levels of their metabolites that have previously been identified in the ocular tissues. Elderly human subjects with and without AMD can safely take supplements of lutein up to 10 mg/d for 6 months with no apparent toxicity or side effects.

Aged↗
PubMed2005

Complement factor H polymorphism in age-related macular degeneration.

Age-related macular degeneration (AMD) is a major cause of blindness in the elderly. We report a genome-wide screen of 96 cases and 50 controls for polymorphisms associated with AMD. Among 116,204 single-nucleotide polymorphisms genotyped, an intronic and common variant in the complement factor H gene (CFH) is strongly associated with AMD (nominal P value <10(-7)). In individuals homozygous for the risk allele, the likelihood of AMD is increased by a factor of 7.4 (95% confidence interval 2.9 to 19). Resequencing revealed a polymorphism in linkage disequilibrium with the risk allele representing a tyrosine-histidine change at amino acid 402. This polymorphism is in a region of CFH that binds heparin and C-reactive protein. The CFH gene is located on chromosome 1 in a region repeatedly linked to AMD in family-based studies.

Aged↗
PubMed2005

The Age-Related Eye Disease Study severity scale for age-related macular degeneration: AREDS Report No. 17.

OBJECTIVE: To develop a fundus photographic severity scale for age-related macular degeneration (AMD). METHODS: In the Age-Related Eye Disease Study, stereoscopic color fundus photographs were taken at baseline, at the 2-year follow-up visit, and annually thereafter. Photographs were graded for drusen characteristics (size, type, area), pigmentary abnormalities (increased pigment, depigmentation, geographic atrophy), and presence of abnormalities characteristic of neovascular AMD (retinal pigment epithelial detachment, serous or hemorrhagic sensory retinal detachment, subretinal or sub-retinal pigment epithelial hemorrhage, subretinal fibrous tissue). Advanced AMD was defined as presence of 1 or more neovascular AMD abnormalities, photocoagulation for AMD, or geographic atrophy involving the center of the macula. We explored associations among right eyes of 3212 participants between severity of drusen characteristics and pigmentary abnormalities at baseline and development of advanced AMD within 5 years of follow-up. RESULTS: A 9-step severity scale that combines a 6-step drusen area scale with a 5-step pigmentary abnormality scale was developed, on which the 5-year risk of advanced AMD increased progressively from less than 1% in step 1 to about 50% in step 9. Among the 334 eyes that had at least a 3-step progression on the scale between the baseline and 5-year visits, almost half showed stepwise progression through intervening severity levels at intervening visits. Replicate gradings showed agreement within 1 step on the scale in 87% of eyes. CONCLUSIONS: The scale provides convenient risk categories and has acceptable reproducibility. Progression along it may prove to be useful as a surrogate for progression to advanced AMD.

Atrophy↗
PubMed2005

A simplified severity scale for age-related macular degeneration: AREDS Report No. 18.

OBJECTIVE: To develop a simplified clinical scale defining risk categories for development of advanced age-related macular degeneration (AMD). METHODS: Following development of a detailed scale for individual eyes based on gradings of fundus photographs in the Age-Related Eye Disease Study, rates of progression to advanced AMD were assessed in cross-tabulations of presence or absence in each eye of 2 easily identified retinal abnormalities, drusen and pigment abnormalities. Large drusen and any pigment changes were particularly predictive of developing advanced AMD. RESULTS: The scoring system developed for patients assigns to each eye 1 risk factor for the presence of 1 or more large (> or = 125 microm, width of a large vein at disc margin) drusen and 1 risk factor for the presence of any pigment abnormality. Risk factors are summed across both eyes, yielding a 5-step scale (0-4) on which the approximate 5-year risk of developing advanced AMD in at least one eye increases in this easily remembered sequence: 0 factors, 0.5%; 1 factor, 3%; 2 factors, 12%; 3 factors, 25%; and 4 factors, 50%. For persons with no large drusen, presence of intermediate drusen in both eyes is counted as 1 risk factor. CONCLUSION: This simplified scale provides convenient risk categories for development of advanced AMD that can be determined by clinical examination or by less demanding photographic procedures than used in the Age-Related Eye Disease Study.

Disease Progression↗
PubMed2005

Central visual function and the NEI-VFQ-25 near and distance activities subscale scores in people with type 1 and 2 diabetes.

PURPOSE: To investigate relationships between clinical measures of central visual function and NEI-VFQ-25 Near and Distance Activities subscales in patients with diabetic retinopathy. DESIGN: Clinic-based, cross-sectional, observational study. METHODS: The NEI-VFQ-25 was administered to 170 people with type 1 or 2 diabetes before an ocular examination that included visual acuity, contrast sensitivity, and central visual fields. Multiple linear regression and exact multiple logistic regression were used to assess the relationship between poor acuity (<69 letters), poor contrast sensitivity (<1.5 log units), and abnormal visual fields (mean deviation < or = -5dB) and NEI-VFQ-25 subscale scores. RESULTS: Final multivariable linear models explained a beta = 4.7 letter difference (P < or = .001) for each 25-point Near Activities subscale score difference. Similar effects were observed for the Distance Activities subscale, although the magnitudes of regression and partial correlation coefficients were lower (beta = 3.3 letters, P < or = .01). Final logistic regression models on abnormal clinical categories of central visual function demonstrated relationships only with the Near Activities subscale. For a 1-point change in Near Activities subscale score, the odds of obtaining a poor score for visual acuity, central visual fields, and contrast sensitivity changed by 0.08 (P < or = .001), 0.07 (P < or = .05), and 0.12 (P < or = .001), respectively. CONCLUSIONS: NEI-VFQ-25 Near and Distance Activities subscales demonstrate utility as measures of central visual function in persons with type 1 or 2 diabetes. Low scores on the NEI-VFQ-25 may reflect poor central visual fields and contrast sensitivity in addition to poor visual acuity.

Adult↗
PubMed2005

Risk factors for the incidence of Advanced Age-Related Macular Degeneration in the Age-Related Eye Disease Study (AREDS) AREDS report no. 19.

PURPOSE: To describe the association of demographic, behavioral, medical, and nonretinal ocular factors with the incidence of neovascular age-related macular degeneration (AMD) and central geographic atrophy (CGA) in the Age-Related Eye Disease Study (AREDS), a randomized trial of antioxidants and zinc supplementation prophylaxis for development of advanced AMD. DESIGN: Clinic-based prospective cohort study. PARTICIPANTS: Of individuals with early or intermediate AMD at baseline with a median follow-up of 6.3 years, 788 were at risk of developing advanced AMD in one eye (the fellow eye had advanced AMD), and 2506 were at risk in both eyes. METHODS: The incidence of neovascular AMD and CGA was assessed from stereoscopic color fundus photographs taken at baseline and at annual visits beginning at year 2. MAIN OUTCOME MEASURES: Neovascular AMD was defined as photocoagulation for choroidal neovascularization, or photographic documentation at the reading center of any of the following: nondrusenoid retinal pigment epithelial detachment, serous or hemorrhagic retinal detachment, hemorrhage under the retina or the retinal pigment epithelium, and subretinal fibrosis. Central geographic atrophy was defined as geographic atrophy involving the center of the macula. RESULTS: In multivariable models, in persons at risk of advanced AMD in both eyes, while controlling for age, gender, and AREDS treatment group, the following variables were statistically significantly associated with the incidence of neovascular AMD: race (odds ratio [OR], white vs. black, 6.77; 95% confidence interval [CI], 1.24-36.9) and larger amount smoked (OR, >10 vs. < or =10 pack-years [a pack-year is an average of 1 pack of cigarette smoked per day for a year], 1.55; 95% CI, 1.15-2.09). The following were statistically significantly associated with the incidence of CGA: less education (OR, high school graduate or less vs. college graduate, 1.75; 95% CI, 1.10-2.78), greater body mass index (BMI) (OR, obese vs. nonobese, 1.93; 95% CI, 1.25-2.65), larger amount smoked (OR, >10 pack-years vs. < or =10 pack-years, 1.82; 95% CI, 1.25-2.65), and antacid use (OR, 0.29; 95% CI, 0.09-0.91). In persons at risk of developing advanced AMD in one eye, the incidence of neovascular AMD was associated with diabetes (OR, 1.88; 95% CI, 1.07-3.31), and the incidence of CGA was associated with use of antiinflammatory medications (OR, 0.22; 95% CI, 0.08-0.59). CONCLUSIONS: Results suggest that, among persons with early or intermediate AMD, smoking and BMI are modifiable factors associated with progression to advanced AMD, and suggest other associations (e.g., use of antacids and antiinflammatory medications) that warrant further study. This article contains additional online-only material available at http://www.ophsource.org/periodicals/ophtha. .

Aged↗
PubMed2005

Serum inflammatory markers in diabetic retinopathy.

PURPOSE: To evaluate the association of serum factors with the severity of diabetic retinopathy and to assess their presence in retinal tissue obtained at autopsy. METHODS: The following serum factors of 93 subjects were examined at the National Eye Institute (NEI) clinical center: the chemokines regulated on activation, normal T-cell expressed and presumably secreted (RANTES)/CCL5, epithelial neutrophil activator (ENA)-78/CXCL5, interferon-induced protein (IP)-10/CXCL10, stromal cell-derived factor (SDF)-1alpha/CXCLl2, monocyte chemoattractant protein (MCP)-1/CCL2, macrophage inflammatory protein (MIP)-1alpha/CCL3, interleukin (IL)-8/CXCL8; the cytokine IL-6; the cell adhesion molecules intercellular adhesion molecule (ICAM-1/CD54) and vascular cell adhesion molecule (VCAM/CD106); and the growth factor vascular endothelial growth factor (VEGF). Logistic regression was performed to assess the association of these factors with age, sex, severity of retinopathy, hemoglobin A(1C), total cholesterol, creatinine, duration of diabetes, and presence of macular edema. The outcome assessed was severity of retinopathy. Frozen sections of two donor eyes obtained at autopsy from a donor with documented severe nonproliferative diabetic retinopathy and diabetic macular edema and of a normal nondiabetic eye were processed by immunoperoxidase staining with primary antibodies against RANTES, MCP-1, ICAM-1, and LFA-1alpha/CD11a. RESULTS: The levels of RANTES and SDF-1alpha were significantly elevated in patients with at least severe nonproliferative diabetic retinopathy compared with those with less severe diabetic retinopathy (P < 0.001 and 0.007, respectively). Positive immunostaining was observed in the inner retina for MCP-1 and RANTES of the patient with diabetes. Staining was strongly positive throughout the diabetic retina for ICAM-1. Normal retinal tissues showed little reactivity. CONCLUSIONS: Serum chemokines were significantly elevated in patients with at least severe nonproliferative diabetic retinopathy compared with those who had less severe retinopathy. Elevated levels of the chemokines and cell adhesion molecules were also identified in eyes of a donor with ischemic diabetic retinopathy. These findings provide evidence to support the role of inflammation in the pathogenesis of diabetic retinopathy.

Biomarkers↗
PubMed2005

Associations of mortality and diabetes complications in patients with type 1 and type 2 diabetes: early treatment diabetic retinopathy study report no. 27.

OBJECTIVE: Diabetes is a leading cause of morbidity and mortality. The purpose of this study is to assess the associations between diabetes complications and mortality in the Early Treatment Diabetic Retinopathy Study (ETDRS). RESEARCH DESIGN AND METHODS: We examined demographic, clinical, and laboratory characteristics of the 3,711 subjects enrolled in the ETDRS, a randomized controlled clinical trial designed to evaluate the role of laser photocoagulation and aspirin therapy for diabetic retinopathy. The outcome assessed was all-cause mortality. Multivariable Cox proportional hazards regression was used to assess associations between diabetes complications and mortality for type 1 and type 2 diabetes separately. RESULTS: The 5-year estimates of all-cause mortality were 5.5 and 18.9% for patients with type 1 and type 2 diabetes, respectively. In patients with type 1 diabetes, amputation (hazard ratio [HR] 5.08 [95% CI 2.06-12.54]) and poor visual acuity (1.74 [1.10-2.75]) remained significantly associated with mortality, after adjusting for other diabetes complications and baseline characteristics. In patients with type 2 diabetes, macrovascular disease and worsening levels of nephropathy, neuropathy, retinopathy, and visual acuity are associated with progressively increasing risks of mortality, after controlling for other baseline risk factors. CONCLUSIONS: Amputation is the strongest predictor for mortality in patients with type 1 diabetes. All complications independently predict mortality in patients with type 2 diabetes. There is an increased risk for mortality as the degree of each complication worsens. Additional studies are needed to investigate the effectiveness of tertiary prevention to decrease mortality in these patients.

Adult↗
PubMed2004

Risk factors for renal replacement therapy in the Early Treatment Diabetic Retinopathy Study (ETDRS), Early Treatment Diabetic Retinopathy Study Report No. 26.

BACKGROUND: Diabetes is a leading cause of end-stage renal disease (ESRD). The purpose of this study is to assess the risk factors for renal replacement therapy (RRT) in the Early Treatment Diabetic Retinopathy Study (ETDRS). METHODS: We examined demographic, clinical, and laboratory characteristics of the 2226 subjects with complete laboratory data enrolled in the ETDRS. The primary renal variable evaluated was the time to development of renal replacement therapy, defined as the need for dialysis or transplantation. Multivariable Cox proportional hazards regression was used to assess risk factors for type 1 and type 2 diabetes separately. RESULTS: The 5-year estimated incidence of RRT in the entire ETDRS population was 10.2% and 9.8% for patients with type 1 and type 2 diabetes, respectively. Of those patients with complete data, 127 of 934 (14%) of patients with type 1 diabetes, and 150 of 1292 (12%) patients with type 2 diabetes required RRT during the study. Baseline risk factors common to type 1 and type 2 diabetes included elevated total cholesterol, and serum creatinine; and low serum albumin and anemia. Other risk factors significant in type 1 diabetes included body mass index (BMI), shorter duration of diabetes, elevated hemoglobin A(1c) (HbA(1c)), elevated systolic blood pressure, and the development of proliferative diabetic retinopathy. Risk factors significant in type 2 diabetes, but not type 1 diabetes, included younger age, proteinuria, and elevated triglycerides. CONCLUSION: In this study, major modifiable risk factors such as hypertension, dyslipidemia, and hyperglycemia were found to be predictive of RRT. Other predictors were markers of vascular pathology and inflammation, proteinuria, hypoalbuminemia, and increased serum creatinine. Controlled clinical trials with treatment strategies that improve serum lipid levels, systemic blood pressure, glycemic control, and markers of inflammation may be important in furthering our knowledge on the pathogenesis of diabetic complications such as nephropathy and ESRD.

Adult↗
PubMed2004

Diabetic retinopathy.

Explore the source record for details and available documents.

Combined Modality Therapy↗
PubMed2003

Potential public health impact of Age-Related Eye Disease Study results: AREDS report no. 11.

OBJECTIVE: To estimate the potential public health impact of the findings of the Age-Related Eye Disease Study (AREDS) on reducing the number of persons developing advanced age-related macular degeneration (AMD) during the next 5 years in the United States. METHODS: The AREDS clinical trial provides estimates of AMD progression rates and of reduction in risk of developing advanced AMD when a high-dose nutritional supplement of antioxidants and zinc is used. These results are applied to estimates of the US population at risk, to estimate the number of people who would potentially avoid advanced AMD during 5 years if those at risk were to take a supplement such as that used in AREDS. RESULTS: An estimated 8 million persons at least 55 years old in the United States have monocular or binocular intermediate AMD or monocular advanced AMD. They are considered to be at high risk for advanced AMD and are those for whom the AREDS formulation should be considered. Of these people, 1.3 million would develop advanced AMD if no treatment were given to reduce their risk. If all of these people at risk received supplements such as those used in AREDS, more than 300,000 (95% confidence interval, 158,000-487,000) of them would avoid advanced AMD and any associated vision loss during the next 5 years. CONCLUSION: If people at high risk for advanced AMD received supplements such as those suggested by AREDS results, the potential impact on public health in the United States would be considerable during the next 5 years.

Antioxidants↗
PubMed2003

Histopathology and regression of retinal hard exudates in diabetic retinopathy after reduction of elevated serum lipid levels.

PURPOSE: To describe a regression of retinal hard exudates in 2 patients with diabetic maculopathy, and to report immunohistologic findings reflecting lipid deposition in the retina. DESIGN: Two interventional case reports. METHODS: Two patients with exudative diabetic maculopathy were treated to normalize serum lipids. Histologic examination and immunohistochemistry of each patient's eyes were performed to assess the localization of apolipoprotein B and cholesteryl ester, both of which are principal components of low-density lipoprotein. RESULTS: Both patients showed a dramatic regression of retinal hard exudates after correction of dyslipidemia. Histopathology revealed diffuse lipids and cholesteryl ester in the retina. Apolipoprotein B and macrophages were colocalized in the perivascular space. CONCLUSIONS: The regression of hard exudates was most likely due to the aggressive lipid lowering in both patients. The novel histopathologic findings of hard exudate and diabetic maculopathy are similar to the pathologic changes observed in larger atherosclerotic lesions, except that they occur in the intraretinal perivascular space.

Adult↗