Ocular Haemodynamic in Early Diabetic and Non Diabetic Patients Undergoing Cataract Phacoemulsification Using Peribulbar Versus Subtenon’s Block

Background: The effect of peribulbar and subtenon’s block on intraocular pressure (IOP) and retinal blood flow (RBF) had been questioned by many investigators. Also, the effect of peribulbar or subtenon anesthesia on ocular blood flow in early diabetic patients had not been studied before.Aim to Work: To assess the effect of these types of block on both the IOP and ocular blood flow in diabetic patients comparing them with a control non diabetic cohort study undergoing cataract phacoemulsification.Study Design: Randomized control trial.Methodology: Eighty patients included in this study were randomly assigned to one of 4 groups divided into 2 groups receiving subtenon block and other 2 groups receiving peribulbar block. Peak systolic velocity was measured immediately before the block, after 1 minute and after 10 minutes of injection of the local anesthetic. Also, IOP, the other parameters measured by the color Doppler imaging including end diastolic velocity, mean vascular pressure, pulsatility index and resistivity index, and the incidence of complications were recorded.Results: The drop of varients (PSV, PI) were significant difference in normal healthy patients and more reduction in early diabetic patients who received peribulbar block while in subtenon block didn’t show any significant difference in MV, PSV, EDV and PI.Conclusion: Subtenon’s block is a safe and effective alternative technique to peribulbar anesthesia that provides more favorable conditions regarding the ocular blood flow specially in diabetic patients who have the risk of potential retinopathy.