Comparative Study of Orbital Doppler Parameters in Hypertensive Patients With and Without Retinopathy

Abstract Background: Hypertensionis a major risk factor for the de-velopment of cardiovascular disorders. Years before end organ damage is clinically evident, hypertension is considered a silent killer. Since retinal arterioles share anatomical and physiologi-cal properties with cerebral and coronary microcirculation, and can be monitored easily and non-invasively, it can thus be con-sidered an in vivo window into the human circulation. Color Doppler Imaging (CDI) is a well-established technology for determining the parameters of orbital blood flow. Aim of Study: To compare changes of color Doppler im-aging (CDI) in the ophthalmic artery and its branches in hy-pertensive patients with retinopathy and without retinopathy in relation to their fundoscopic changes. Patients and Methods: This observational study included 80 hypertensive patients, divided into 3 groups according to Wong and Mitchell Classification: No retinopathy (Group 1), with mild-moderate Retinopathy (Group 2), and with severe Retinopathy (Group 3). All did Orbital CDI in which Ophthal-mic Artery (OA), Central Retinal Artery (CRA) and Ciliary Arteries (CA) were identified. Peak systolic velocity (PSV), End Diastolic velocity (EDV) and Resistivity Index (RI) were measured. Results: CRA RIwas highest in G3 (p=0.05). OA EDV was significantly higher in G1 vs G3 (p=0.013). On the contrary, OA RI was lower in G1 vs G2 (p=0.010), and vs G3 (p=0.000). HTN duration showed a significant negative correlation with CRA EDV (r=-0.237, p=0.034); a significant positive correla-tionwith CRA RI (r=0.280, p=0.012) as well as with CA RI (r=0.288, p=0.010). Regarding HTN control, CRA PSV and EDV were significantly higher in stage 1 HTN (p=0.033 and 0.036 respectively), while CRA RI was significantly higher in isolated systolic HTN (p-value 0.029). OA PSV was signfic-natly lower among patients with isolated systolic HTN vs con-trolled and stage 1 HTN patients (p=0.004 and 0.009). Correspondence to: Dr. Aya M.S. Aly, The Department of Diagnostic & Interventional Radiology, Faculty of Medicine, Cairo University Conclusion: RI of orbital arteries mainly OA and CRA, may serve as good predictors for microvascular changes of the retina especially in patients with poorly controlled HTN of long duration.