Associations of maternal retinal vasculature with subsequent fetal growth and birth size

10.1371/journal.pone.0118250PLoS ONE104e0118250GUSTO (Growing up towards Healthy Outcomes

Posterior eye shape measurement with retinal OCT compared to MRI

PURPOSE. Posterior eye shape assessment by magnetic resonance imaging (MRI) is used to study myopia. We tested the hypothesis that optical coherence tomography (OCT), as an alternative, could measure posterior eye shape similarly to MRI. METHODS. Macular spectral-domain OCT and brain MRI images previously acquired as part of the Singapore Epidemiology of Eye Diseases study were analyzed. The right eye in the MRI and OCT images was automatically segmented. Optical coherence tomography segmentations were corrected for optical and display distortions requiring biometry data. The segmentations were fitted to spheres and ellipsoids to obtain the posterior eye radius of curvature (Rc) and asphericity (Qxz). The differences in Rc and Qxz measured by MRI and OCT were tested using paired t-tests. Categorical assignments of prolateness or oblateness using Qxz were compared. RESULTS. Fifty-two subjects (67.8 ± 5.6 years old) with spherical equivalent refraction from +0.50 to -5.38 were included. The mean paired difference between MRI and original OCT posterior eye Rc was 24.03 ± 46.49 mm (P = 0.0005). For corrected OCT images, the difference in Rc decreased to -0.23 ± 2.47 mm (P = 0.51). The difference between MRI and OCT asphericity, Qxz, was -0.052 ± 0.343 (P = 0.28). However, categorical agreement was only moderate (j = 0.50). CONCLUSIONS. Distortion-corrected OCT measurements of Rc and Qxz were not statistically significantly different from MRI, although the moderate categorical agreement suggests that individual differences remained. This study provides evidence that with distortion correction, noninvasive office-based OCT could potentially be used instead of MRI for the study of posterior eye shape

Retinal Vascular Geometry and Glaucoma: The Singapore Malay Eye Study

National Medical Research Council [0796/2003]; Biomedical Research Council [501/1/25-5]Purpose: To determine the associations of geometric measurements (tortuosity, branching angle, and fractal dimension) of retinal vessels with glaucoma. Design: Population-based, cross-sectional study. Participants: Persons aged 40 to 80 years who participated in the Singapore Malay Eye Study (n = 3280; 78.7% response rate). Methods: Quantitative retinal vascular parameters (tortuosity, branching angle, and fractal dimension) were measured from digital retinal fundus photographs using a computer-assisted program following a standardized grading protocol. Glaucoma was diagnosed according to the International Society of Geographic and Epidemiological Ophthalmology classification system. Main Outcome Measures: The associations among retinal vascular parameters with glaucoma, the main glaucoma subtype primary open-angle glaucoma (POAG), and ocular hypertension (OHT). Results: A total of 123 persons (4.4% of the 2789 participants) had glaucoma in the final analysis, 87 (70.7%) of whom were diagnosed with POAG. After adjusting for age, sex, body mass index, diabetes, hypertension, smoking, axial length, and intraocular pressure (IOP), decreased retinal arteriolar tortuosity (odds ratio [OR], 1.73; 95% confidence interval [CI], 1.38-2.18, comparing lowest vs. highest quartiles), decreased retinal venular tortuosity (OR, 1.59; 95% CI, 1.29-1.97), and narrower retinal venular branching angle (OR, 1.22; 95% CI, 1.00-1.48) were associated with glaucoma. Similar associations were found between these retinal vascular parameters and POAG. Decreased retinal vascular fractal dimension was associated with OHT (OR 1.37; 95% CI, 1.04-1.82). Conclusions: Certain features of retinal vascular geometry are associated with glaucomatous optic neuropathy independently of vascular risk factors and IOP

Relationship of Intraocular Pressure with Central Aortic Systolic Pressure

<p><i>Purpose</i>: To examine the relationship between central aortic systolic pressure (CASP) and intraocular pressure (IOP), and to compare the strength of any association with that of peripheral blood pressure and IOP.</p> <p><i>Methods</i>: Adults ranging in age from 40 to 80 years were consecutively recruited from the population-based Singapore Chinese Eye Study. We measured CASP using arterial tonometry (BPro) and IOP using Goldmann applanation tonometry. All participants had a standardized examination including a complete ophthalmic and systemic examination. Systolic blood pressure (SBP) and diastolic blood pressure (DBP) were measured using peripheral blood pressure cuff. Univariable and multiple linear regression analyses were performed to examine the relationship between CASP and IOP. Standardized regression coefficients (sβ) were calculated to compare the associations between CASP and SBP with IOP.</p> <p><i>Results</i>: A total of 372 consecutive Chinese participants were analyzed. After adjusting for age, gender, body mass index, total cholesterol, use of antihypertensive medication and central corneal thickness, each 10 mmHg increase in CASP was associated with 0.32 mmHg of IOP elevation [95% confidence interval (CI): 0.10–0.53, sβ = 0.160, <i>p</i> value = 0.004]. SBP also had a positive relationship with IOP (<i>β</i> = 0.279, 95% CI: 0.079–0.479, sβ = 0.152, <i>p</i> value = 0.006). Associations between IOP and CASP, SBP and DBP were similar in participants using antihypertensive medication to participant not using antihypertensives.</p> <p><i>Conclusions</i>: Increased CASP, as measured by arterial tonometry, is associated with higher IOP. Our results strengthen the relationship between systemic blood pressure and IOP.</p

Retinal Vascular Fractals and Cognitive Impairment

Background: Retinal microvascular network changes have been found in patients with age-related brain diseases such as stroke and dementia including Alzheimer's disease. We examine whether retinal microvascular network changes are also present in preclinical stages of dementia. Methods: This is a cross-sectional study of 300 Chinese participants (age: ≥60 years) from the ongoing Epidemiology of Dementia in Singapore study who underwent detailed clinical examinations including retinal photography, brain imaging and neuropsychological testing. Retinal vascular parameters were assessed from optic disc-centered photographs using a semiautomated program. A comprehensive neuropsychological battery was administered, and cognitive function was summarized as composite and domain-specific Z-scores. Cognitive impairment no dementia (CIND) and dementia were diagnosed according to standard diagnostic criteria. Results: Among 268 eligible nondemented participants, 78 subjects were categorized as CIND-mild and 69 as CIND-moderate. In multivariable adjusted models, reduced retinal arteriolar and venular fractal dimensions were associated with an increased risk of CIND-mild and CIND-moderate. Reduced fractal dimensions were associated with poorer cognitive performance globally and in the specific domains of verbal memory, visuoconstruction and visuomotor speed. Conclusion: A sparser retinal microvascular network, represented by reduced arteriolar and venular fractal dimensions, was associated with cognitive impairment, suggesting that early microvascular damage may be present in preclinical stages of dementia

Retinal vascular caliber and age-related macular degeneration in an Indian population from Singapore

Purpose: To examine the association between retinal vascular caliber and early age-related macular degeneration (AMD) in an Indian population. Methods: A total of 3112 Indian participants aged ≥40 years from the population-based Singapore Indian Eye Study who had data available on retinal vascular caliber measurements and AMD status were included. Retinal arteriolar and venular calibers were measured from digital photographs using computer-assisted software according to a standardized protocol. Images of the macular region were graded according to the modified Wisconsin age-related maculopathy grading system. Right eyes were selected for analyses. Binary logistic regression models were used to assess the association, adjusting for age, sex, systolic blood pressure, total cholesterol, random blood glucose, body mass index, and the companion retinal vascular caliber. Results: A total of 107 participants (3.4%) were diagnosed with early AMD. Neither arteriolar nor venular caliber was related to AMD. For early AMD, the age-, sex-, and companion retinal vascular caliber-adjusted odds ratio (OR) per standard deviation (SD) decrease in arteriolar caliber was 0.95 (95% CI 0.84-1.31; p=0.671), and per SD increase in venular caliber was OR: 0.96 (95% CI: 0.77-1.20); p=0.714. No trend was found after categorizing retinal vascular calibers into quartiles. Multivariate adjustment and stratified analyses did not alter these results. Conclusion: Retinal vascular calibers were not related to early AMD among Indian participants. These findings differ from those of several previous studies performed in Caucasian and Asian populations.</p

Gestational hypertensive disorders and retinal microvasculature: The Generation R Study

__Background:__ Changes in the microvasculature associated with pre-eclampsia and gestational hypertension have been proposed as a potential pathway in the development of cardiovascular disease. We examined whether gestational hypertensive disorders, such as pre-eclampsia and gestational hypertension, are related to the maternal retinal microvasculature status after pregnancy. __Methods:__ This study is part of an ongoing population-based prospective cohort study. During pregnancy and 6.2 years after the index pregnancy, we examined 3391 women with available information on pre-eclampsia, gestational hypertension, and retinal vascular calibers. Retinal arteriolar and venular calibers were measured in the left eye from digitized retinal photographs. __Results:__ Women with pre-eclampsia had smaller retinal arteriolar calibers 6 years after pregnancy than women with a normotensive pregnancy. For women with previous gestational hypertension, similar trends were observed. With respect to retinal venular calibers, we did not observe consistent trends for women with previous pre-eclampsia. However, in women with previous gestational hypertension, we observed larger venular calibers than in women with a previous normotensive pregnancy. The association of gestational hypertensive disorders with retinal vessel calibers was mediated through mean arterial pressure at the time of retinal imaging. __Conclusions:__ Compared to women with a previous normotensive pregnancy, women with pre-eclampsia and gestational hypertension show an altered status of the microvasculature 6 years after the index pregnancy. This is reflected by smaller retinal arteriolar calibers and wider retinal venular calibers. These microvascular changes may possibly contribute to the development of cardiovascular disease in later life