The Experts below are selected from a list of 20544 Experts worldwide ranked by ideXlab platform
Tien Yin Wong - One of the best experts on this subject based on the ideXlab platform.
-
body fat distribution metabolic and inflammatory markers and retinal microvasculature in school age children the generation r study
International Journal of Obesity, 2015Co-Authors: Olta Gishti, Tien Yin Wong, Vincent W V Jaddoe, Albert Hofman, M K Ikram, Romy GaillardAbstract:To examine the associations of body fatness, metabolic and inflammatory markers with retinal vessel Calibers among children. We performed a population-based cohort study among 4145 school-age children. At the median age of 6.0 years (95% range 5.8, 8.0 years), we measured body mass index, total and abdominal fat mass, metabolic and inflammatory markers (blood levels of lipids, insulin and C-peptide and C-reactive protein) and retinal vascular Calibers from retinal photographs. We observed that compared with normal weight children, obese children had narrower retinal arteriolar Caliber (difference −0.21 s.d. score (SDS; 95% confidence interval (CI) −0.35, −0.06)), but not venular Caliber. Continuous analyses showed that higher body mass index and total body fat mass, but not android/gynoid fat mass ratio and pre-peritoneal fat mass, were associated with narrower retinal arteriolar Caliber (P<0.05 for body mass index and total body fat mass), but not with retinal venular Caliber. Lipid and insulin levels were not associated with retinal vessel Calibers. Higher C-reactive protein was associated with only wider retinal venular Caliber (difference 0.10 SDS (95% CI 0.06, 0.14) per SDS increase in C-reactive protein). This latter association was not influenced by body mass index. Higher body fatness is associated with narrower retinal arteriolar Caliber, whereas increased C-reactive protein levels are associated with wider retinal venular Caliber. Increased fat mass and inflammation correlate with microvascular development from school-age onwards.
-
complete blood count and retinal vessel Calibers
PLOS ONE, 2014Co-Authors: Gerald Liew, Tien Yin Wong, Jie Jin Wang, Elena Rochtchina, Paul MitchellAbstract:Objective The influence of hematological indices such as complete blood count on microcirculation is poorly understood. Retinal microvasculature can be directly visualized and vessel Calibers are associated with a range of ocular and systemic diseases. We examined the association of complete blood count with retinal vessel Calibers. Methods Cross-sectional population-based Blue Mountains Eye Study, n = 3009, aged 49+ years. Complete blood count was measured from fasting blood samples taken at baseline examination, 1992–4. Retinal arteriolar and venular Calibers were measured from digitized retinal photographs using a validated semi-automated computer program. Results All analyses adjusted for age, sex, systolic blood pressure, diabetes, smoking and fellow vessel Caliber. Higher hematocrit, white cell count and platelet count were associated with narrower arteriolar Caliber (p = 0.02, 0.03 and 0.001 respectively), while higher hemoglobin, hematocrit, red cell count, white cell count and platelet count were associated with wider venular Caliber (p<0.0001 for all). Each quintile increase in hematocrit, white cell count and platelet count was associated with approximately 0.5 µm narrower arteriolar Caliber; whereas each quintile increase in all of the complete blood count components was associated with approximately 1–2 µm wider venular Caliber. Conclusions These associations show that elevated levels of hematological indices can have adverse effects on the microcirculation.
-
retinal vascular Caliber measurements clinical significance current knowledge and future perspectives
Ophthalmologica, 2013Co-Authors: Kamran Ikram, Yi Ting Ong, Carol Y Cheung, Tien Yin WongAbstract:The retinal vasculature provides a unique window to assess vascular health noninvasively and directly in vivo. Advances in fundus photography and retinal image analysis techniques have enabled the objective and accurate assessment of quantitative retinal vascular Caliber measurement. Over the last decade, large population-based studies have shown that retinal vascular Calibers are associated with a wide range of subclinical (e.g. atherosclerosis, inflammation and endothelial dysfunction) and clinical cardiovascular diseases (hypertension, diabetes mellitus, stroke, kidney and heart diseases). However, while retinal image analysis provided exciting possibilities to study the pathogenesis of these diseases, its direct applicability in a clinical setting as a 'test' to predict cardiovascular diseases is yet to be established, particularly within the context of being used as a population screening tool. Nevertheless, with continual development of retinal imaging techniques and newer understanding of the clinical significance of these retinal changes, there remains scope for the development of retinal vascular Caliber measurements as a biomarker for vascular disease risk assessment in targeted areas and patient subgroups (e.g. patients with diabetes, suspected hypertension and stroke).
-
blood pressure is associated with retinal vessel signs in preadolescent children
Journal of Hypertension, 2010Co-Authors: Bamini Gopinath, Gerald Liew, Tien Yin Wong, Jie Jin Wang, Louise A Baur, Erdahl Teber, Ning Cheung, Paul MitchellAbstract:OBJECTIVE Few studies have examined the effect of blood pressure (BP) on the retinal microvasculature in children. We examined the relationship between BP and retinal vessel Caliber in a sample of preadolescent schoolchildren. METHODS Eligible high school students [2353/3144 (response 75.3%); mean age, 12.7 years] from 21 randomly selected schools in Sydney, Australia, were examined during 2004-2005. Retinal vessel Caliber was quantified from digital retinal images using well known computer-based programs. BP was measured using a standard protocol and high BP was defined according to published guidelines for this age group. RESULTS After adjusting for age, sex, ethnicity, BMI, iris color, axial length, birth weight and the fellow retinal vascular Caliber, children in the highest quartiles of SBP, DBP or mean arterial BP had approximately 5 mum narrower mean retinal arteriolar Caliber than those in the lowest quartiles of all three BP measures (all P for trend <0.0001). Children classified as having high BP had approximately 2.0 mum narrower mean retinal arteriolar Caliber than normotensive children (P = 0.002). In boys, each 10-mmHg increase in SBP was associated with a 2.19-mum increase in the mean retinal venular Caliber (P = 0.0003), but no similar significant association was evident in girls. CONCLUSION Elevated BP is associated with narrower retinal arterioles in preadolescent boys and girls, and also with wider retinal venules in boys. These data provide further evidence of early microvascular changes associated with high BP in older children.
-
low birthweight is associated with narrower arterioles in adults
Hypertension, 2008Co-Authors: Gerald Liew, Paul Mitchell, Richey A Sharrett, Ronald Klein, Jie Jin Wang, Bruce Bartholow Duncan, Frederick Brancati, Hsin Chieh Yeh, Tien Yin WongAbstract:Low birthweight is associated with increased risk of hypertension, but underlying mechanisms are obscure. We hypothesized structural microvascular alterations may be one such mechanism. We examined the association of birthweight and retinal arteriolar Caliber in 3800 persons aged 51 to 72 years participating in a population-based study in 4 US communities (the Atherosclerosis Risk in Communities study). Participants reported full-term birth and their birthweight and had retinal photography. Retinal arteriolar and venular Calibers were measured from digitized retinal photographs using a validated computer-assisted method. Lower birthweight was associated with narrower retinal arteriolar Caliber, with each kg lower birthweight associated with 2.4 mum (95% confidence intervals, 1.3 to 3.5, P<0.001) narrower retinal arteriolar Caliber, after controlling for age, gender, race, education, smoking, alcohol consumption, adult body mass index, and height. Additional adjustment for blood pressure averaged over the past 6 years and fasting glucose did not alter these findings, with each kg lower birthweight associated with a 1.7 mum (95% confidence intervals, 0.7 to 2.8, P<0.001) narrower retinal arteriolar Caliber. This association was also present in persons without hypertension or diabetes. Lower birthweight was not associated with retinal venular Caliber. These findings provide evidence that structural alterations in the arteriolar microcirculation may be a potential mechanism linking restricted fetal growth with subsequent risk of hypertension.
Paul Mitchell - One of the best experts on this subject based on the ideXlab platform.
-
retinal vessel Caliber changes in vasculitis
Retina-the Journal of Retinal and Vitreous Diseases, 2015Co-Authors: Gerald Liew, Paul Mitchell, Adnan Tufail, Victoria F Cosatto, Ava Grace Tan, Javier Zarranzventura, Dawn A Sim, Pearse A Kean, Catherine A Egan, Mark WestcottAbstract:Background: Retinal vasculitis is a potentially sight-threatening inflammation of the retinal vessels, but little is known about the in vivo vascular changes, which occur in affected eyes. The authors therefore sought to measure vessel Caliber in eyes with vasculitis. Methods: Retrospective case–control study. Vasculitis was confirmed using fluorescein angiography. Vessel Calibers were measured using validated semiautomated software. Results: There were 21 eyes from 15 patients with vasculitis and 33 control eyes from 21 control subjects. Most cases were diagnosed with idiopathic vasculitis. All had periphlebitis, and one eye also had arteritis. After adjustment for age and gender, mean arteriolar Caliber was 143 μm (95% confidence interval [CI], 134–152) in cases and 158 μm (95% CI, 151–165) in controls (P = 0.01). Venular Caliber was similar in cases (229 μm; 95% CI, 215–243) and controls (228 μm; 95% CI, 217–234; P = 0.91), whereas arteriole-to-venule ratio was smaller in cases (0.63; 95% CI, 0.60–0.66) compared with controls (0.70; 95% CI, 0.02–0.11; P = 0.004). Conclusion: Retinal vasculitis was associated with narrower arteriolar Caliber, whereas venular Caliber was similar to controls. This resulted in a smaller arteriole-to-venule ratio in eyes with vasculitis.
-
complete blood count and retinal vessel Calibers
PLOS ONE, 2014Co-Authors: Gerald Liew, Tien Yin Wong, Jie Jin Wang, Elena Rochtchina, Paul MitchellAbstract:Objective The influence of hematological indices such as complete blood count on microcirculation is poorly understood. Retinal microvasculature can be directly visualized and vessel Calibers are associated with a range of ocular and systemic diseases. We examined the association of complete blood count with retinal vessel Calibers. Methods Cross-sectional population-based Blue Mountains Eye Study, n = 3009, aged 49+ years. Complete blood count was measured from fasting blood samples taken at baseline examination, 1992–4. Retinal arteriolar and venular Calibers were measured from digitized retinal photographs using a validated semi-automated computer program. Results All analyses adjusted for age, sex, systolic blood pressure, diabetes, smoking and fellow vessel Caliber. Higher hematocrit, white cell count and platelet count were associated with narrower arteriolar Caliber (p = 0.02, 0.03 and 0.001 respectively), while higher hemoglobin, hematocrit, red cell count, white cell count and platelet count were associated with wider venular Caliber (p<0.0001 for all). Each quintile increase in hematocrit, white cell count and platelet count was associated with approximately 0.5 µm narrower arteriolar Caliber; whereas each quintile increase in all of the complete blood count components was associated with approximately 1–2 µm wider venular Caliber. Conclusions These associations show that elevated levels of hematological indices can have adverse effects on the microcirculation.
-
blood pressure is associated with retinal vessel signs in preadolescent children
Journal of Hypertension, 2010Co-Authors: Bamini Gopinath, Gerald Liew, Tien Yin Wong, Jie Jin Wang, Louise A Baur, Erdahl Teber, Ning Cheung, Paul MitchellAbstract:OBJECTIVE Few studies have examined the effect of blood pressure (BP) on the retinal microvasculature in children. We examined the relationship between BP and retinal vessel Caliber in a sample of preadolescent schoolchildren. METHODS Eligible high school students [2353/3144 (response 75.3%); mean age, 12.7 years] from 21 randomly selected schools in Sydney, Australia, were examined during 2004-2005. Retinal vessel Caliber was quantified from digital retinal images using well known computer-based programs. BP was measured using a standard protocol and high BP was defined according to published guidelines for this age group. RESULTS After adjusting for age, sex, ethnicity, BMI, iris color, axial length, birth weight and the fellow retinal vascular Caliber, children in the highest quartiles of SBP, DBP or mean arterial BP had approximately 5 mum narrower mean retinal arteriolar Caliber than those in the lowest quartiles of all three BP measures (all P for trend <0.0001). Children classified as having high BP had approximately 2.0 mum narrower mean retinal arteriolar Caliber than normotensive children (P = 0.002). In boys, each 10-mmHg increase in SBP was associated with a 2.19-mum increase in the mean retinal venular Caliber (P = 0.0003), but no similar significant association was evident in girls. CONCLUSION Elevated BP is associated with narrower retinal arterioles in preadolescent boys and girls, and also with wider retinal venules in boys. These data provide further evidence of early microvascular changes associated with high BP in older children.
-
prediction of incident stroke events based on retinal vessel Caliber a systematic review and individual participant meta analysis
American Journal of Epidemiology, 2009Co-Authors: Kevi Mcgeecha, Gerald Liew, Petra Macaskill, Les Irwig, Ronald Klei, Arbara E K Klei, Jie Ji Wang, Paul Mitchell, Johannes R Vingerling, Paulus T V M De JongAbstract:The Caliber of the retinal vessels has been shown to be associated with stroke events. However, the consistency and magnitude of association, and the changes in predicted risk independent of traditional risk factors, are unclear. To determine the association between retinal vessel Caliber and the risk of stroke events, the investigators combined individual data from 20,798 people, who were free of stroke at baseline, in 6 cohort studies identified from a search of the Medline (National Library of Medicine, Bethesda, Maryland) and EMBASE (Elsevier B.V., Amsterdam, the Netherlands) databases. During follow-up of 5–12 years, 945 (4.5%) incident stroke events were recorded. Wider retinal venular Caliber predicted stroke (pooled hazard ratio = 1.15, 95% confidence interval: 1.05, 1.25 per 20-μm increase in Caliber), but the Caliber of retinal arterioles was not associated with stroke (pooled hazard ratio = 1.00, 95% confidence interval: 0.92, 1.08). There was weak evidence of heterogeneity in the hazard ratio for retinal venular Caliber, which may be attributable to differences in follow-up strategies across studies. Inclusion of retinal venular Caliber in prediction models containing traditional stroke risk factors reassigned 10.1% of people at intermediate risk into different, mostly lower, risk categories.
-
low birthweight is associated with narrower arterioles in adults
Hypertension, 2008Co-Authors: Gerald Liew, Paul Mitchell, Richey A Sharrett, Ronald Klein, Jie Jin Wang, Bruce Bartholow Duncan, Frederick Brancati, Hsin Chieh Yeh, Tien Yin WongAbstract:Low birthweight is associated with increased risk of hypertension, but underlying mechanisms are obscure. We hypothesized structural microvascular alterations may be one such mechanism. We examined the association of birthweight and retinal arteriolar Caliber in 3800 persons aged 51 to 72 years participating in a population-based study in 4 US communities (the Atherosclerosis Risk in Communities study). Participants reported full-term birth and their birthweight and had retinal photography. Retinal arteriolar and venular Calibers were measured from digitized retinal photographs using a validated computer-assisted method. Lower birthweight was associated with narrower retinal arteriolar Caliber, with each kg lower birthweight associated with 2.4 mum (95% confidence intervals, 1.3 to 3.5, P<0.001) narrower retinal arteriolar Caliber, after controlling for age, gender, race, education, smoking, alcohol consumption, adult body mass index, and height. Additional adjustment for blood pressure averaged over the past 6 years and fasting glucose did not alter these findings, with each kg lower birthweight associated with a 1.7 mum (95% confidence intervals, 0.7 to 2.8, P<0.001) narrower retinal arteriolar Caliber. This association was also present in persons without hypertension or diabetes. Lower birthweight was not associated with retinal venular Caliber. These findings provide evidence that structural alterations in the arteriolar microcirculation may be a potential mechanism linking restricted fetal growth with subsequent risk of hypertension.
Gerald Liew - One of the best experts on this subject based on the ideXlab platform.
-
retinal vessel Caliber changes in vasculitis
Retina-the Journal of Retinal and Vitreous Diseases, 2015Co-Authors: Gerald Liew, Paul Mitchell, Adnan Tufail, Victoria F Cosatto, Ava Grace Tan, Javier Zarranzventura, Dawn A Sim, Pearse A Kean, Catherine A Egan, Mark WestcottAbstract:Background: Retinal vasculitis is a potentially sight-threatening inflammation of the retinal vessels, but little is known about the in vivo vascular changes, which occur in affected eyes. The authors therefore sought to measure vessel Caliber in eyes with vasculitis. Methods: Retrospective case–control study. Vasculitis was confirmed using fluorescein angiography. Vessel Calibers were measured using validated semiautomated software. Results: There were 21 eyes from 15 patients with vasculitis and 33 control eyes from 21 control subjects. Most cases were diagnosed with idiopathic vasculitis. All had periphlebitis, and one eye also had arteritis. After adjustment for age and gender, mean arteriolar Caliber was 143 μm (95% confidence interval [CI], 134–152) in cases and 158 μm (95% CI, 151–165) in controls (P = 0.01). Venular Caliber was similar in cases (229 μm; 95% CI, 215–243) and controls (228 μm; 95% CI, 217–234; P = 0.91), whereas arteriole-to-venule ratio was smaller in cases (0.63; 95% CI, 0.60–0.66) compared with controls (0.70; 95% CI, 0.02–0.11; P = 0.004). Conclusion: Retinal vasculitis was associated with narrower arteriolar Caliber, whereas venular Caliber was similar to controls. This resulted in a smaller arteriole-to-venule ratio in eyes with vasculitis.
-
complete blood count and retinal vessel Calibers
PLOS ONE, 2014Co-Authors: Gerald Liew, Tien Yin Wong, Jie Jin Wang, Elena Rochtchina, Paul MitchellAbstract:Objective The influence of hematological indices such as complete blood count on microcirculation is poorly understood. Retinal microvasculature can be directly visualized and vessel Calibers are associated with a range of ocular and systemic diseases. We examined the association of complete blood count with retinal vessel Calibers. Methods Cross-sectional population-based Blue Mountains Eye Study, n = 3009, aged 49+ years. Complete blood count was measured from fasting blood samples taken at baseline examination, 1992–4. Retinal arteriolar and venular Calibers were measured from digitized retinal photographs using a validated semi-automated computer program. Results All analyses adjusted for age, sex, systolic blood pressure, diabetes, smoking and fellow vessel Caliber. Higher hematocrit, white cell count and platelet count were associated with narrower arteriolar Caliber (p = 0.02, 0.03 and 0.001 respectively), while higher hemoglobin, hematocrit, red cell count, white cell count and platelet count were associated with wider venular Caliber (p<0.0001 for all). Each quintile increase in hematocrit, white cell count and platelet count was associated with approximately 0.5 µm narrower arteriolar Caliber; whereas each quintile increase in all of the complete blood count components was associated with approximately 1–2 µm wider venular Caliber. Conclusions These associations show that elevated levels of hematological indices can have adverse effects on the microcirculation.
-
blood pressure is associated with retinal vessel signs in preadolescent children
Journal of Hypertension, 2010Co-Authors: Bamini Gopinath, Gerald Liew, Tien Yin Wong, Jie Jin Wang, Louise A Baur, Erdahl Teber, Ning Cheung, Paul MitchellAbstract:OBJECTIVE Few studies have examined the effect of blood pressure (BP) on the retinal microvasculature in children. We examined the relationship between BP and retinal vessel Caliber in a sample of preadolescent schoolchildren. METHODS Eligible high school students [2353/3144 (response 75.3%); mean age, 12.7 years] from 21 randomly selected schools in Sydney, Australia, were examined during 2004-2005. Retinal vessel Caliber was quantified from digital retinal images using well known computer-based programs. BP was measured using a standard protocol and high BP was defined according to published guidelines for this age group. RESULTS After adjusting for age, sex, ethnicity, BMI, iris color, axial length, birth weight and the fellow retinal vascular Caliber, children in the highest quartiles of SBP, DBP or mean arterial BP had approximately 5 mum narrower mean retinal arteriolar Caliber than those in the lowest quartiles of all three BP measures (all P for trend <0.0001). Children classified as having high BP had approximately 2.0 mum narrower mean retinal arteriolar Caliber than normotensive children (P = 0.002). In boys, each 10-mmHg increase in SBP was associated with a 2.19-mum increase in the mean retinal venular Caliber (P = 0.0003), but no similar significant association was evident in girls. CONCLUSION Elevated BP is associated with narrower retinal arterioles in preadolescent boys and girls, and also with wider retinal venules in boys. These data provide further evidence of early microvascular changes associated with high BP in older children.
-
prediction of incident stroke events based on retinal vessel Caliber a systematic review and individual participant meta analysis
American Journal of Epidemiology, 2009Co-Authors: Kevi Mcgeecha, Gerald Liew, Petra Macaskill, Les Irwig, Ronald Klei, Arbara E K Klei, Jie Ji Wang, Paul Mitchell, Johannes R Vingerling, Paulus T V M De JongAbstract:The Caliber of the retinal vessels has been shown to be associated with stroke events. However, the consistency and magnitude of association, and the changes in predicted risk independent of traditional risk factors, are unclear. To determine the association between retinal vessel Caliber and the risk of stroke events, the investigators combined individual data from 20,798 people, who were free of stroke at baseline, in 6 cohort studies identified from a search of the Medline (National Library of Medicine, Bethesda, Maryland) and EMBASE (Elsevier B.V., Amsterdam, the Netherlands) databases. During follow-up of 5–12 years, 945 (4.5%) incident stroke events were recorded. Wider retinal venular Caliber predicted stroke (pooled hazard ratio = 1.15, 95% confidence interval: 1.05, 1.25 per 20-μm increase in Caliber), but the Caliber of retinal arterioles was not associated with stroke (pooled hazard ratio = 1.00, 95% confidence interval: 0.92, 1.08). There was weak evidence of heterogeneity in the hazard ratio for retinal venular Caliber, which may be attributable to differences in follow-up strategies across studies. Inclusion of retinal venular Caliber in prediction models containing traditional stroke risk factors reassigned 10.1% of people at intermediate risk into different, mostly lower, risk categories.
-
low birthweight is associated with narrower arterioles in adults
Hypertension, 2008Co-Authors: Gerald Liew, Paul Mitchell, Richey A Sharrett, Ronald Klein, Jie Jin Wang, Bruce Bartholow Duncan, Frederick Brancati, Hsin Chieh Yeh, Tien Yin WongAbstract:Low birthweight is associated with increased risk of hypertension, but underlying mechanisms are obscure. We hypothesized structural microvascular alterations may be one such mechanism. We examined the association of birthweight and retinal arteriolar Caliber in 3800 persons aged 51 to 72 years participating in a population-based study in 4 US communities (the Atherosclerosis Risk in Communities study). Participants reported full-term birth and their birthweight and had retinal photography. Retinal arteriolar and venular Calibers were measured from digitized retinal photographs using a validated computer-assisted method. Lower birthweight was associated with narrower retinal arteriolar Caliber, with each kg lower birthweight associated with 2.4 mum (95% confidence intervals, 1.3 to 3.5, P<0.001) narrower retinal arteriolar Caliber, after controlling for age, gender, race, education, smoking, alcohol consumption, adult body mass index, and height. Additional adjustment for blood pressure averaged over the past 6 years and fasting glucose did not alter these findings, with each kg lower birthweight associated with a 1.7 mum (95% confidence intervals, 0.7 to 2.8, P<0.001) narrower retinal arteriolar Caliber. This association was also present in persons without hypertension or diabetes. Lower birthweight was not associated with retinal venular Caliber. These findings provide evidence that structural alterations in the arteriolar microcirculation may be a potential mechanism linking restricted fetal growth with subsequent risk of hypertension.
Jie Jin Wang - One of the best experts on this subject based on the ideXlab platform.
-
complete blood count and retinal vessel Calibers
PLOS ONE, 2014Co-Authors: Gerald Liew, Tien Yin Wong, Jie Jin Wang, Elena Rochtchina, Paul MitchellAbstract:Objective The influence of hematological indices such as complete blood count on microcirculation is poorly understood. Retinal microvasculature can be directly visualized and vessel Calibers are associated with a range of ocular and systemic diseases. We examined the association of complete blood count with retinal vessel Calibers. Methods Cross-sectional population-based Blue Mountains Eye Study, n = 3009, aged 49+ years. Complete blood count was measured from fasting blood samples taken at baseline examination, 1992–4. Retinal arteriolar and venular Calibers were measured from digitized retinal photographs using a validated semi-automated computer program. Results All analyses adjusted for age, sex, systolic blood pressure, diabetes, smoking and fellow vessel Caliber. Higher hematocrit, white cell count and platelet count were associated with narrower arteriolar Caliber (p = 0.02, 0.03 and 0.001 respectively), while higher hemoglobin, hematocrit, red cell count, white cell count and platelet count were associated with wider venular Caliber (p<0.0001 for all). Each quintile increase in hematocrit, white cell count and platelet count was associated with approximately 0.5 µm narrower arteriolar Caliber; whereas each quintile increase in all of the complete blood count components was associated with approximately 1–2 µm wider venular Caliber. Conclusions These associations show that elevated levels of hematological indices can have adverse effects on the microcirculation.
-
blood pressure is associated with retinal vessel signs in preadolescent children
Journal of Hypertension, 2010Co-Authors: Bamini Gopinath, Gerald Liew, Tien Yin Wong, Jie Jin Wang, Louise A Baur, Erdahl Teber, Ning Cheung, Paul MitchellAbstract:OBJECTIVE Few studies have examined the effect of blood pressure (BP) on the retinal microvasculature in children. We examined the relationship between BP and retinal vessel Caliber in a sample of preadolescent schoolchildren. METHODS Eligible high school students [2353/3144 (response 75.3%); mean age, 12.7 years] from 21 randomly selected schools in Sydney, Australia, were examined during 2004-2005. Retinal vessel Caliber was quantified from digital retinal images using well known computer-based programs. BP was measured using a standard protocol and high BP was defined according to published guidelines for this age group. RESULTS After adjusting for age, sex, ethnicity, BMI, iris color, axial length, birth weight and the fellow retinal vascular Caliber, children in the highest quartiles of SBP, DBP or mean arterial BP had approximately 5 mum narrower mean retinal arteriolar Caliber than those in the lowest quartiles of all three BP measures (all P for trend <0.0001). Children classified as having high BP had approximately 2.0 mum narrower mean retinal arteriolar Caliber than normotensive children (P = 0.002). In boys, each 10-mmHg increase in SBP was associated with a 2.19-mum increase in the mean retinal venular Caliber (P = 0.0003), but no similar significant association was evident in girls. CONCLUSION Elevated BP is associated with narrower retinal arterioles in preadolescent boys and girls, and also with wider retinal venules in boys. These data provide further evidence of early microvascular changes associated with high BP in older children.
-
low birthweight is associated with narrower arterioles in adults
Hypertension, 2008Co-Authors: Gerald Liew, Paul Mitchell, Richey A Sharrett, Ronald Klein, Jie Jin Wang, Bruce Bartholow Duncan, Frederick Brancati, Hsin Chieh Yeh, Tien Yin WongAbstract:Low birthweight is associated with increased risk of hypertension, but underlying mechanisms are obscure. We hypothesized structural microvascular alterations may be one such mechanism. We examined the association of birthweight and retinal arteriolar Caliber in 3800 persons aged 51 to 72 years participating in a population-based study in 4 US communities (the Atherosclerosis Risk in Communities study). Participants reported full-term birth and their birthweight and had retinal photography. Retinal arteriolar and venular Calibers were measured from digitized retinal photographs using a validated computer-assisted method. Lower birthweight was associated with narrower retinal arteriolar Caliber, with each kg lower birthweight associated with 2.4 mum (95% confidence intervals, 1.3 to 3.5, P<0.001) narrower retinal arteriolar Caliber, after controlling for age, gender, race, education, smoking, alcohol consumption, adult body mass index, and height. Additional adjustment for blood pressure averaged over the past 6 years and fasting glucose did not alter these findings, with each kg lower birthweight associated with a 1.7 mum (95% confidence intervals, 0.7 to 2.8, P<0.001) narrower retinal arteriolar Caliber. This association was also present in persons without hypertension or diabetes. Lower birthweight was not associated with retinal venular Caliber. These findings provide evidence that structural alterations in the arteriolar microcirculation may be a potential mechanism linking restricted fetal growth with subsequent risk of hypertension.
-
measurement of retinal vascular Caliber issues and alternatives to using the arteriole to venule ratio
Investigative Ophthalmology & Visual Science, 2007Co-Authors: Gerald Liew, Paul Mitchell, Tien Yin Wong, Richey A Sharrett, Richard A Kronmal, Ronald Klein, Annette Kifley, Jie Jin WangAbstract:PURPOSE. The arteriole to venule ratio (AVR) is widely used in studies of the associations of retinal microvascular disease with systemic and ocular outcomes. This is a discussion of the limitations of AVR; a comparison of its predictive information with that of its components, arteriolar and venular Caliber; and a description of a suggested alternative method of modeling arteriolar and venular Calibers directly. METHODS. Data from the population-based Blue Mountains Eye Study were used to compare the predictive information in models using AVR with models using arteriolar and venular Calibers directly. Determination was made of how the apparent relationship between vessel Caliber and two systemic outcomes (blood pressure [BP] and white blood cell count [WBC]) was influenced by the choice of regression model. These findings were interpreted with reference to the known biological relationship among vessel Calibers, BP, and WBC. RESULTS. Models using arteriolar and venular Calibers directly had more predictive information than models using AVR. The apparent relationship of vessel Caliber to BP and WBC differed substantially, depending on the model chosen. For example, after adjustment for age, sex, and other covariates, decreasing venular Caliber was associated with higher systolic BP when modeled separately, but was associated with lower systolic BP when modeled simultaneously with arteriolar Caliber. CONCLUSIONS. The findings suggest AVR provides less information with regards to predicting systemic outcomes than its two components. Modeling arteriolar and venular Calibers separately could be biased by confounding, while modeling both simultaneously appears to provide unbiased, biologically plausible results. The use of this approach is recommended in future research relating retinal vascular Caliber to systemic or ocular outcomes.
-
Measurement of retinal vascular Caliber: issues and alternatives to using the arteriole to venule ratio. Invest Ophthalmol Vis Sci.
2007Co-Authors: Gerald Liew, Paul Mitchell, Tien Yin Wong, Richey A Sharrett, Richard A Kronmal, Ronald Klein, Annette Kifley, Jie Jin WangAbstract:PURPOSE. The arteriole to venule ratio (AVR) is widely used in studies of the associations of retinal microvascular disease with systemic and ocular outcomes. This is a discussion of the limitations of AVR; a comparison of its predictive information with that of its components, arteriolar and venular Caliber; and a description of a suggested alternative method of modeling arteriolar and venular Calibers directly. METHODS. Data from the population-based Blue Mountains Eye Study were used to compare the predictive information in models using AVR with models using arteriolar and venular Calibers directly. Determination was made of how the apparent relationship between vessel Caliber and two systemic outcomes (blood pressure [BP] and white blood cell count [WBC]) was influenced by the choice of regression model. These findings were interpreted with reference to the known biological relationship among vessel Calibers, BP, and WBC. RESULTS. Models using arteriolar and venular Calibers directly had more predictive information than models using AVR. The apparent relationship of vessel Caliber to BP and WBC differed substantially, depending on the model chosen. For example, after adjustment for age, sex, and other covariates, decreasing venular Caliber was associated with higher systolic BP when modeled separately, but was associated with lower systolic BP when modeled simultaneously with arteriolar Caliber. CONCLUSIONS. The findings suggest AVR provides less information with regards to predicting systemic outcomes than its two components. Modeling arteriolar and venular Calibers separately could be biased by confounding, while modeling both simultaneously appears to provide unbiased, biologically plausible results. The use of this approach is recommended in future research relating retinal vascular Caliber to systemic or ocular outcomes. (Invest Ophthalmol Vis Sci. 2007;48:52-57
Ramazan Yagci - One of the best experts on this subject based on the ideXlab platform.
-
retinal nerve fiber layer thickness and retinal vessel Calibers in children with thalassemia minor
Sage Open Medicine, 2016Co-Authors: Semra Acer, Tt Ongun, Yasemin Isik Balci, Gokhan Pekel, Aziz Polat, Ebru Nevin Cetin, Ramazan YagciAbstract:OBJECTIVES Evaluation of the peripapillary retinal nerve fiber layer thickness, subfoveal choroidal thickness, and retinal vessel Caliber measurements in children with thalassemia minor. METHODS In this cross-sectional and comparative study, 30 thalassemia minor patients and 36 controls were included. Heidelberg spectral domain optical coherence tomography was used for peripapillary retinal nerve fiber layer thickness, subfoveal choroidal thickness, and retinal vessel Caliber measurements. RESULTS There was no statistically significant difference in retinal nerve fiber layer thickness and subfoveal choroidal thickness between the two groups (p > 0.05). There was no correlation between retinal nerve fiber layer thickness and hemoglobin values. Both the arterioral and venular Calibers were higher in thalassemia minor group (p < 0.05). CONCLUSION There is increased retinal arterioral and venular Calibers in children with thalassemia minor compared with controls.
-
Retinal nerve fiber layer thickness and retinal vessel Calibers in children with thalassemia minor.
SAGE open medicine, 2016Co-Authors: Semra Acer, Tt Ongun, Yasemin Isik Balci, Gokhan Pekel, Aziz Polat, Ebru Nevin Cetin, Ramazan YagciAbstract:OBJECTIVES Evaluation of the peripapillary retinal nerve fiber layer thickness, subfoveal choroidal thickness, and retinal vessel Caliber measurements in children with thalassemia minor. METHODS In this cross-sectional and comparative study, 30 thalassemia minor patients and 36 controls were included. Heidelberg spectral domain optical coherence tomography was used for peripapillary retinal nerve fiber layer thickness, subfoveal choroidal thickness, and retinal vessel Caliber measurements. RESULTS There was no statistically significant difference in retinal nerve fiber layer thickness and subfoveal choroidal thickness between the two groups (p > 0.05). There was no correlation between retinal nerve fiber layer thickness and hemoglobin values. Both the arterioral and venular Calibers were higher in thalassemia minor group (p
