Read by QxMD icon Read

Retinal vascular calibre

Valli Velayutham, Paul Z Benitez-Aguirre, Maria E Craig, Gerald Liew, Tien Y Wong, Alicia J Jenkins, Kim C Donaghue
AIMS/HYPOTHESIS: Retinal imaging enables non-invasive microvasculature assessment; however, only central retinal vessels have been studied in type 1 diabetes. Peripheral smaller vessels have a major haemodynamic role and may differ from central vessels in their response to the diabetic milieu. We hypothesise that diabetes has a greater impact on peripheral retinal vessels vs central vessels. METHODS: Retinal photographs from adolescents (n = 736; age 12-20 years) with type 1 diabetes were graded (Singapore I Vessel Assessment) with vessel calibres measured in the 'central zone' as central retinal arteriolar and venular equivalents (CRAE and CRVE, respectively) and the 'extended zone' as mean width of arterioles and venules (MWa and MWv, respectively)...
July 15, 2017: Diabetologia
Carol Yim-Lui Cheung, Charumathi Sabanayagam, Antony Kwan-Pui Law, Neelam Kumari, Daniel Shu-Wei Ting, Gavin Tan, Paul Mitchell, Ching Yu Cheng, Tien Yin Wong
AIMS/HYPOTHESIS: We aimed to examine prospectively the association between a range of retinal vascular geometric variables measured from retinal photographs and the 6 year incidence and progression of diabetic retinopathy. METHODS: We conducted a prospective, population-based cohort study of Asian Malay individuals aged 40-80 years at baseline (n = 3280) who returned for a 6 year follow-up. Retinal vascular geometric variables (tortuosity, branching, fractal dimension, calibre) were measured from baseline retinal photographs using a computer-assisted program (Singapore I Vessel Assessment)...
June 16, 2017: Diabetologia
R Heitmar, G Y H Lip, R E Ryder, A D Blann
BACKGROUND: Retinal vessel calibre and vascular dilation/constriction in response to flicker light provocation may provide a measure distinguishing patients suffering from diabetes mellitus and/or cardiovascular disease. METHODS: One hundred and sixteen age and sex matched patients with diabetes mellitus (DM), cardiovascular disease (CVD) and both DM and CVD (DM + CVD) underwent systemic and intraocular pressure measurements. Retinal vessel calibres were assessed using a validated computer-based program to compute central retinal artery and vein equivalents (CRVE) from monochromatic retinal images...
April 26, 2017: Cardiovascular Diabetology
Wei Xiao, Xinxing Guo, Xiaohu Ding, Mingguang He
The present study aims to assess the relationship between serum lipid parameters and retinal microvascular calibres in children and adolescents. A total of 950 participants aged 7 to 19 years were recruited. Central retinal arteriolar equivalent (CRAE) and central retinal venular equivalent (CRVE) were measured from digital retinal images. Serological testing was performed to obtain lipid profiles. Dyslipidaemia was defined according to the US national expert panel guideline. After adjusted for age, sex, mean arterial blood pressure, axial length, body mass index and the fellow retinal vascular calibre, no significant association was found between retinal vascular diameters and any lipid parameters (all P > 0...
March 20, 2017: Scientific Reports
Sanjeewa S Wickremasinghe, Samantha Fraser-Bell, Elizabeth Alessandrello, Hemal Mehta, Mark C Gillies, Lyndell L Lim
PURPOSE: To compare changes in retinal vascular calibre after 2 years of treatment with intravitreal bevacizumab (BVZ) or dexamethasone implant (DEX) in patients with centre-involving diabetic macular oedema (DMO). METHODS: At baseline, 88 eyes of 61 patients with DMO were recruited in a prospective, multicentre, randomised, single-masked clinical trial. Of these subjects, 22 BVZ-treated (52%) and 22 DEX-treated (48%) eyes of 34 patients (56%) had gradable retinal photographs at both the baseline and 24-month visits...
February 22, 2017: British Journal of Ophthalmology
Stuart Keel, Catherine Itsiopoulos, Konstandina Koklanis, Meri Vukicevic, Fergus Cameron, Laima Brazionis
BACKGROUND: The aim of the study was to describe the relationship of retinal arteriolar and venular calibre with vascular risk factors in children and adolescents with type 1 diabetes. METHODS: In this hospital-based cross-sectional study, the medical files of 483 children and adolescents with type 1 diabetes were audited to collect retinal images and relevant clinical data. Retinal vascular calibre was measured using standardised protocols. RESULTS: After multivariable adjustments, a vascular risk profile that included: older age, higher serum creatinine, higher systolic blood pressure (SBP), higher body mass index (BMI), abnormal estimated glomerular filtration rate (eGFR), lower high-density lipoproteins (HDL) cholesterol, longer duration of diabetes and higher serum sodium was associated with narrower central retinal artery equivalent (CRAE) (95% CI=-4...
March 1, 2017: Journal of Pediatric Endocrinology & Metabolism: JPEM
Nadine Reichhart, Sergio Crespo-Garcia, Nadine Haase, Michaela Golic, Sergej Skosyrski, Anne Rübsam, Christina Herrspiegel, Norbert Kociok, Natalia Alenina, Michael Bader, Ralf Dechend, Olaf Strauss, Antonia M Joussen
AIMS/HYPOTHESIS: Although the renin-angiotensin system plays an important role in the progression of diabetic retinopathy, its influence therein has not been systematically evaluated. Here we test the suitability of a new translational model of diabetic retinopathy, the TetO rat, for addressing the role of angiotensin-II receptor 1 (AT1) blockade in experimental diabetic retinopathy. METHODS: Diabetes was induced by tetracycline-inducible small hairpin RNA (shRNA) knockdown of the insulin receptor in rats, generating TetO rats...
January 2017: Diabetologia
Ling-Jun Li, Peng Guan Ong, Marjorelee T Colega, Chad Yixian Han, Ling Wei Chen, Ryan Man Eyn Kidd, Ecosse Lamoureux, Peter Gluckman, Kenneth Kwek, Yap Seng Chong, Seang Mei Saw, Keith M Godfrey, Tien Yin Wong, Mary Chong Foong-Fong
BACKGROUND: Imbalanced macronutrient intakes can induce impairment of endothelial and vascular function, and further lead to metabolic and cardiovascular disease. However, little is known about the influence of such diets on endothelial and vascular dysfunction in pregnant women, even though high-fat diet is a known risk for pregnancy complications such as gestational diabetes and pre-eclampsia. OBJECTIVE: We aimed to assess the association between maternal macronutrient intakes (protein, fat and carbohydrates), dietary quality and retinal microvascular changes in a multi-ethnic Asian mother-offspring cohort...
2016: PloS One
Rupesh Agrawal, Nichole Joachim, Ling-Jun Li, Jiaying Lee, Aniruddha Agarwal, Dawn A Sim, Pearse A Keane, Gerald Liew, Carlos E Pavesio
PURPOSE: Birdshot chorioretinopathy (BCR) is a potentially blinding ocular disorder involving the retinal vasculature and choroid without any systemic manifestations. The objective of the study was to describe vascular calibre changes in BCR and analyse the possibility of this optical biomarker for staging and monitoring disease activity in BCR. METHODS: This retrospective case-control study at a tertiary referral eye centre in the UK included 33 eyes from 21 patients with BCR and equal number of eyes from control subjects...
March 2017: Acta Ophthalmologica
Seung Uk Lee, Ki Yup Nam, Sang Joon Lee
The aim of the study is to investigate the retinal vascular calibre, retinal nerve fibre layer's thickness, and optic disc changes in patients after pars plana vitrectomy. We examined 40 eyes in 40 patients who had undergone unilateral pars plana vitrectomy at three time points: prior to surgery, and at 3 and 6 months after the operation. The diameters of central retinal arteries and veins were measured using retinal photographs. The central retinal arteriolar equivalent (CRAE) and central retinal venular equivalent (CRVE) were calculated using the revised Parr-Hubbard formula...
August 4, 2016: International Ophthalmology
Alexander R Newman, Nicholas H Andrew, Robert J Casson
Recent studies have supported the hypothesis that exposure to established cardiovascular risk factors in early life predisposes to the development of adult cardiovascular disease. Retinal imaging is an emerging technique which facilitates non-invasive, accurate and reproducible assessment of the retinal microvasculature. The assessment may be in the form of static vascular calibre measurements and assessment of the vascular geometry or dynamic structural and functional assessments. Paediatric retinal microvascular changes are reported in response to elevated blood pressure, type 1 diabetes, increasing adiposity, diet, physical activity, systemic inflammation, metabolic peptides, family history and prenatal factors...
January 2017: Clinical & Experimental Ophthalmology
Georgios Leontidis, Bashir Al-Diri, Andrew Hunter
Retinal vessel calibre has been found to be an important biomarker of several retinal diseases, including diabetic retinopathy (DR). Quantifying the retinal vessel calibres is an important step for estimating the central retinal artery and vein equivalents. In this study, an alternative method to the already established branching coefficient (BC) is proposed for summarising the vessel calibres in retinal junctions. This new method combines the mean diameter ratio with an alternative to Murray׳s cube law exponent, derived by the fractal dimension,experimentally, and the branch exponent of cerebral vessels, as has been suggested in previous studies with blood flow modelling...
May 1, 2016: Computers in Biology and Medicine
Michél Strauss, Wayne Smith, Aletta E Schutte
BACKGROUND: Bilateral systolic blood pressure (SBP) differences > 10mmHg is a common finding in clinical practice. Such BP differences in older individuals are associated with peripheral vascular disease, linked to microvascular dysfunction. Investigating retinal vessel calibres could provide insight into systemic microvascular function and may predict cardiovascular outcomes. Therefore we investigated the link between inter-arm systolic blood pressure differences (IASBPD) and the retinal microvasculature to determine the usefulness of IASBPD as an early marker of microvascular changes...
August 2016: Heart, Lung & Circulation
Peter Skov Jensen, Simon Metz Mariendal Pedersen, Christian Aalkjaer, Toke Bek
PURPOSE: Disturbances in the diameter regulation of the larger retinal vessels are involved in the pathophysiology of a number of vision threatening retinal diseases, but the role of the smaller vessels has received less attention. Therefore, an experimental model was developed for studying diameter changes in retinal vessels at all branching levels secondary to pharmacological interventions ex vivo. METHODS: Porcine hemiretinas were mounted in a tissue chamber that allowed the control of temperature, pH and oxygen saturation...
August 2016: Acta Ophthalmologica
Leoné Malan, Mark Hamer, Roland von Känel, Markus P Schlaich, Manja Reimann, Nancy Frasure-Smith, Gavin W Lambert, Walthard Vilser, Brian H Harvey, Faans Steyn, Nico T Malan
BACKGROUND: Depression has been associated with impaired nitric oxide (NO)-mediated vasodilation and vascular dysregulation (VD). Whether depression and NO levels will disturb retinal haemodynamics is not clear. OBJECTIVES AND METHODS: Associations between the retinal vasculature, diastolic ocular perfusion pressure (DOPP) as measure of hypoperfusion, NO metabolites (NOx) and depression symptoms were assessed. Chronic VD risk markers [depression symptoms (Patient Health Questionnaire/PHQ-9 ≥ 10) and 24 h pulse pressure] were determined in a bi-ethnic cohort (n = 313; 48...
May 1, 2016: Nitric Oxide: Biology and Chemistry
Xiufen Yang, Yu Deng, Hong Gu, Xuetao Ren, Apiradee Lim, Torkel Snellingen, Xipu Liu, Ningli Wang, Jeong Won Pak, Ningpu Liu, Ronald P Danis
AIMS: To describe the relationship of retinal arteriolar and venular calibre with diabetic retinopathy (DR) and related risk factors, including glucose levels and other biomarkers in a Chinese population with type 2 diabetes mellitus (T2DM). METHODS: A cross-sectional study. Patients with T2DM were recruited from a local community in urban Beijing. Seven fields 30° colour fundus photographs were taken and examined for the presence and severity of DR using a standardised grading system...
October 2016: British Journal of Ophthalmology
Takatoshi Tano, Koichi Ono, Yoshimune Hiratsuka, Koji Otani, Miho Sekiguchi, Shinichi Konno, Shinichi Kikuchi, Yoshihiro Onishi, Misa Takegami, Masakazu Yamada, Shunichi Fukuhara, Akira Murakami
PURPOSE: To describe the relationship between retinal vascular calibre and cardiovascular risk factors in a Japanese population. METHODS: The Locomotive Syndrome and Health Outcome in Aizu Cohort Study is a population-based, cross-sectional survey that included 2346 persons (56.1% of the eligible population) aged 40 to 74 years old. Retinal vascular calibre was measured from digital retinal photographs using a validated standardized protocol. Data on major cardiovascular risk factors were collected from all participants...
September 2016: Acta Ophthalmologica
György Kovács, András Hajdu
The automated processing of retinal images is a widely researched area in medical image analysis. Screening systems based on the automated and accurate recognition of retinopathies enable the earlier diagnosis of diseases like diabetic retinopathy, hypertension and their complications. The segmentation of the vascular system is a crucial task in the field: on the one hand, the accurate extraction of the vessel pixels aids the detection of other anatomical parts (like the optic disc Hoover and Goldbaum, 2003) and lesions (like microaneurysms Sopharak et al...
April 2016: Medical Image Analysis
Qi Lun Ooi, Foong Kien Newk-Fon Hey Tow, Raj Deva, Ryo Kawasaki, Tien Y Wong, Deb Colville, Francesco Ierino, Anastasia Hutchinson, Judy Savige
BACKGROUND/AIMS: Individuals who reach end-stage kidney disease (CKD5) have a high risk of vascular events that persists even after renal transplantation. This study compared the prevalence and severity of microvascular disease in transplant recipients and patients with CKD5. METHODS: Individuals with a renal transplant or CKD5 were recruited consecutively from renal clinics, and underwent bilateral retinal photography (Canon CR5-45, Canon). Their retinal images were deidentified and reviewed for hypertensive/microvascular signs by an ophthalmologist and a trained grader (Wong and Mitchell classification), and for vessel caliber at a grading centre using a computer-assisted method and Knudtson's modification of the Parr-Hubbard formula...
2015: Kidney & Blood Pressure Research
Nico T Malan, Wayne Smith, Roland von Känel, Mark Hamer, Alta E Schutte, Leoné Malan
BACKGROUND: Low levels of testosterone in men and changes in retinal microvascular calibre are both associated with hypertension and cardiovascular disease risk. Sex hormones are also associated with blood flow in microvascular beds which might be a key intermediate mechanism in the development of hypertension. Whether a direct association between endogenous testosterone and retinal microvascular calibre exists is currently unknown. We aimed to determine whether testosterone is independently associated with ocular perfusion via a possible association with retinal vascular calibre or whether it plays only a secondary role via its effect on blood pressure in a bi-ethnic male cohort...
November 2015: VASA. Zeitschrift Für Gefässkrankheiten
Fetch more papers »
Fetching more papers... Fetching...
Read by QxMD. Sign in or create an account to discover new knowledge that matter to you.
Remove bar
Read by QxMD icon Read

Search Tips

Use Boolean operators: AND/OR

diabetic AND foot
diabetes OR diabetic

Exclude a word using the 'minus' sign

Virchow -triad

Use Parentheses

water AND (cup OR glass)

Add an asterisk (*) at end of a word to include word stems

Neuro* will search for Neurology, Neuroscientist, Neurological, and so on

Use quotes to search for an exact phrase

"primary prevention of cancer"
(heart or cardiac or cardio*) AND arrest -"American Heart Association"