Evaluation of retrobulbar circulation in type 2 diabetic patients using color Doppler imaging

Abstract

Purpose: To investigate the retrobulbar circulatory parameters in type 2 diabetes mellitus patients with color Doppler imaging (CDI) and compare the results with nondiabetic controls. Methods: This prospective study included 50 type 2 diabetic patients and 50 age-matched controls. Seven field stereo fundus photography was used to diagnose and classify diabetic retinopathy (DR). Diabetic patients were further divided into two: Group 1, consisted of patients with no DR, mild and moderate non-proliferative DR ( n = 36); Group 2, severe nonproliferative and proliferative DR ( n = 14). CDI was performed using Philips iU22 xMATRIX ultrasound. The peak systolic velocity (PSV), end-diastolic velocity (EDV), resistivity index (RI) and pulsatile index (PI) of ophthalmic (OA), posterior ciliary artery (PCA), and central retinal artery (CRA) along with central retinal vein (CRV) were recorded. Results: RI in the ophthalmic artery was significantly higher in both DR groups than the control group ( P = 0.000). Diabetic Group 1 had decreased blood flow velocity (PSV and EDV) in PCA compared to controls ( P = 0.046 and P = 0.010, respectively). Group 2 DR had significantly reduced EDV and increased RI in CRA compared to Group 1 ( P = 0.015). Binary logistic regression analysis revealed glycosylated hemoglobin and RI of OA to be independent risk factors of DR. Conclusion: Significant changes in resistivity index and flow velocities were observed in the retrobulbar vessels, especially in ophthalmic artery in diabetics compared to controls. CDI with results of increased resistance or decreased flow could be useful to predict individuals at higher risk for developing severe DR.

Ophthalmic Artery Morphological and Hemodynamic Features in Acute Coronary Syndrome

“…The increased resistance or decreased flow in retrobulbar blood flow in patients with hypertension or diabetes have been reported. 25 , 26 …”

Intravital Imaging of Circulating Red Blood Cells in the Retinal Vasculature of Growing Mice

“…Notably, it enabled direct simultaneous high-resolution imaging and tracking of individual RBCs flowing in all types of retinal vessels, arteries, veins, and capillaries discriminating individual vessel segments and branches. In comparison, previously reported retinal blood flow imaging techniques based on Doppler ultrasonography, Doppler OCT, OCT angiography, and laser speckle flowgraphy 9 , 10 , 12 , 16 – 18 , 20 – 23 could not measure single-cell-level blood flow in the retinal vasculature. Recent advance of a scanning laser ophthalmoscope has reported successful visualization of single-cell blood flow in the retina of small animal models.…”

“… 13 Accurate and quantitative measurement of the blood flow in the retinal vasculature can provide valuable information to improve our understanding of the pathophysiology of retinal vasculopathy. 9 , 10 , 12 , 19 , 20 Several clinical trials have used the retinal blood flow as a diagnostic biomarker for retinal vasculopathy based on clinically available instruments, including Doppler ultrasonography, 20 , 21 Doppler optical coherence tomography (OCT), 9 , 10 , 22 OCT angiography, 12 , 17 , 23 and laser speckle flowgraphy. 16 , 18 …”

Diagnostic and predictive value of resistive / pulsatility indices of ophthalmic artery and common carotid artery for the development of diabetic retinopathy

“…Balasopoulou et al reported a significant difference in the RI and PI values of the OA between controls and diabetic patients with different DRP groups. But they stated similar variation in OA flow velocities between groups (28). Conversely, the mean of the CCA PI was significantly differentiated in both the control, PDRP, DMwoRP, and NPDRP groups but the mean of OA PI was significantly higher in the PDRP group compared to the control and DMwoRP groups.…”