Can pulsatile ocular blood flow distinguish between patients with and without diabetic retinopathy? (original) (raw)
Related papers
Pulsatile ocular blood flow in untreated diabetic retinopathy
Acta Ophthalmologica Scandinavica, 2009
Purpose: To measure the pulsatile component of total ocular blood flow in patients with untreated diabetic retinopathy.Subjects and Methods: An adapted pneumotonometer attached to a slit-lamp biomicroscope. 82 age-matched subjects divided into 4 groups: non-diabetic controls (n = 22); diabetics with no clinical retinopathy (n = 20); background diabetic retinopathy (n = 20); pre-proliferative/proliferative diabetic retinopathy (n = 20).Results: The mean pulsatile ocular blood flow values were found to be increased in all grades of diabetic retinopathy (no retinopathy 818 μl/min, background 1015 μl/min, pre-proliferative/proliferative 1097 μl/min) compared to the control group (644 μl/min). These pulsatile ocular blood flow values were significantly higher (p<0.05) in the background and pre-proliferative/proliferate retinopathy groups compared to controls. Pulse volume and pulse amplitude were also higher in the diabetic subjects. Mean arterial blood pressure did not differ across the groups studied.Conclusion: Pulsatile ocular blood flow was found to be higher in diabetics compared to controls and appears to increase as the severity of retinopathy progresses. Such a hyperdynamic circulation may contribute to the pathogenesis of diabetic eye disease.
Investigative ophthalmology & visual science, 1996
The authors investigated retinal blood flow changes in patients with insulin-dependent diabetes mellitus (IDDM) and no diabetic retinopathy compared to age-matched subjects without diabetes. They also investigated whether blood glucose levels could modulate retinal blood flow in these patients with diabetes and whether this modulation would impact retinal blood flow data used in cross-sectional studies assessing changes in retinal blood flow. Retinal blood flow was measured using video fluorescein angiography, and blood glucose levels were manipulated using glucose clamp methodologies with continuous basal insulin replacement. Blood glucose levels were clamped at 100, 200, and 300 mg/dl. Retinal blood flow measurements were performed at each blood glucose level after subjects had been stabilized for an hour at each of the different blood glucose levels. Retinal blood flow was found to be significantly decreased (P< 0.01) in the group of patients with no diabetic retinopathy (19.4...
Journal of Diabetes Science and Technology, 2012
Background: The aim of this study was to investigate early morphological and functional pathology in the retinal micro-circulation in patients with insulin resistance and/or type 2 diabetes mellitus (T2DM). Methods: Fifty-four subjects, without features of retinopathy under ophthalmological investigation, were recruited for study participation and were classifed into three study groups according to their metabolic staging: (1) Group C comprised nondiabetic, insulin-sensitive subjects with a BMI <28kg/m2; (2) Group IR comprised nondiabetic, insulin-resistant, obese subjects with a BMI ≥28 kg/m2; and (3) Group DM comprised patients with manifested T2DM. Retinal microvascular blood flow was assessed using scanning laser doppler flowmetry (Heidelberg Retina Flowmeter) before and after flicker light stimulation (10 Hz; Photo Stimulater 750). Results: No significant difference was observed in retinal blood flow (RBF) among the three groups, neither at baseline nor after stimulating the...
IP Innovative Publication Pvt. Ltd, 2017
Introduction: The World Health Organization (WHO) has estimated that the number of people diagnosed with Diabetes is 347 million worldwide. Diabetic macular edema (DME) and Diabetic Retinopathy are the main causes of vision loss in Diabetes mellitus. Objective: To compare altered ocular blood flow by Doppler evaluation in middle aged type 2 diabetic patients with and without diabetic macular edema. Materials and Methods: An analytical cross–sectional study was conducted in the outpatient and in-patient department of ophthalmology and the department of radiodiagnosis in a tertiary care hospital including 36 patients in each group (A-with DME & B-without DME). Color doppler was done to evaluate ocular blood flow velocities in internal carotid, ophthalmic and central retinal arteries and central retinal vein. Results: The majority of diabetes patients in developing countries are middle aged (45–64 years of age). Vascular changes and subsequent ocular hemodynamic changes are critical events in the pathogenesis of diabetic retinopathy. Mean Resistivity Index (RI) and Mean Pulsatility Index (PI) in the ophthalmic artery were found to be significantly high in the DME group. Mean end diastolic velocity (EDV) in the common carotid artery was found to be significantly high in the NO DME group than the DME group. In our study, the mean values of Low Density Lipoprotein (LDL) (mg/dl) , Total cholesterol (mg/dl) , Serum urea (mg/dl), Serum creatinine (mg/dl) was found to be higher (Statistically significant) in the DME group as compared to NO DME group. Conclusion: Our findings may indicate disturbances of retinal and choroidal circulation in patients with DME. Further studies with larger groups of patients are needed to understand better the role of retrobulbar hemodynamics in the pathogenesis of Diabetic macular edema.
Turkish Journal of Medical Sciences, 2014
To prospectively assess the effects of panretinal photocoagulation (PRP) treatment on pulsatile ocular blood flow (POBF) in patients with proliferative diabetic retinopathy (PDRP). The study included 40 eyes with PDRP in 27 patients. The PRP treatments were completed in 3 sessions with 3-week intervals. The intraocular pressure (IOP), pulse amplitude (PA), pulse volume (PV), and POBF changes that arose during the sessions were recorded using a blood flow analyzer. The average age of the patients was 57.37 ± 11.14 years. The pre-PRP basal IOP, PA, PV, and POBF values were 20.44 ± 4.13 mmHg, 4.23 ± 1.73 mmHg, 6.89 ± 2.28 μL, and 21.86 ± 5.83 μL/s, respectively. One month after the completion of the PRP sessions, the values were 18.49 ± 4.44 mmHg, 2.78 ± 1.13 mmHg, 5.27 ± 2.08 μL, and 15.89 ± 5.05 μL/s, respectively, and the differences were significant (P = 0.001, P < 0.0001, P < 0.0001, and P < 0.0001, respectively). PRP treatment reduces the choroidal blood flow and consequ...
Ophthalmology, 1985
To quantify the vascular deterioration of the diabetic retina, retinal circulatory changes in 45 insulin-dependent diabetic patients, and in 17 normal controls, were measured and divided into four groups according to severity of retinopathy. The noninvasive laser Doppler technique was used to measure the systolic/diastolic variation of red blood cell velocity (V) at sites along temporal retinal arteries. Flow pulsatility [V (systole)fV ( diastole)] was 18% lower (P < 0.00001) in the mild-retinopathy group than in normal controls, but 35% higher (P < 0.001) in the severe-retinopathy group than in the mild-retinopathy
Graefe's Archive for Clinical and Experimental Ophthalmology, 2003
Background: To identify alterations of retinal capillary blood flow in the papillomacular area in preclinical diabetic retinopathy using the Heidelberg scanning laser Doppler flowmeter. Methods: Ten eyes from ten patients with type 2 diabetes and no lesions visible on fundus photography (level 10 of Wisconsin grading) and ten eyes from ten healthy subjects of similar age range were examined with the HRF. Intravisit reproducibility of retinal capillary blood flow measurements was assessed in normal subjects and in type 2 diabetic patients, comparing different measurement areas and different analysis procedures: (a) 10×10 pixel box with original software, (b) 10×10 pixel box with SLDF software, and (c) whole-scan analysis with SLDF software (automatic full-field perfusion image analysis). Results: Intravisit reproducibility for the whole-scan analysis in the papillomacular area was 3.52%, 4.81% and 4.60% for volume (VOL), flow (FLW) and velocity (VEL) respectively. Using this method, mean and SD values for retinal capillary blood-flow are 13.25±2.87, 214.58±55.30 and 0.74±0.17, for VOL, FLW and VEL for healthy eyes, comparing with 19.85±6.22, 360.87±158.70 and 1.20±0.48 in eyes with preclinical diabetic retinopathy (P<0.010, P<0.019 and P<0.015 respectively). Conclusions: The HRF shows acceptable reproducibility when using whole-scan analysis in the papillomacular area. Retinal capillary blood VOL, FLW and VEL were particularly increased in five of the ten diabetic eyes examined, with values over the mean + 2SD of the control population, suggesting that eyes showing increased retinal capillary blood flow may indicate risk of progression.