Transient central retina artery occlusion in patients undergone intravitreal anti-vascular endothelial growth factor injections

Purpose To evaluate the occurrence of transient central retinal artery occlusion following intravitreal anti-vascular endothelial growth factor injection. Methods Prospective, observational study of 807 patients (807 eyes) who were given intravitreal injections of ranibizumab or aflibercept to treat any cause of retinal vascular diseases between 1 January 2017 and 30 November 2018 at the Federal Fluminense University Hospital in Niteroi, and a private facility in Rio de Janeiro, Brazil. Patients who did not present transient central retinal artery occlusion were excluded. Results Among 4069 injections, only 18 patients (0.44%) presented transient central retinal artery occlusion, 14 mild cases (77.7%), and 4 severe cases (22.3%). The clinical factors associated with more severe cases of transient central retinal artery occlusion were the duration of the transient central retinal artery occlusion ( p = 0.001), number of prior injections ( p = 0.01), and a positive carotid Doppler test ( p = 0.01). Twelve cases (66.6%) had positive carotid artery obstruction (atheroma plaque size ≥70%) while 6 cases (33.3%) had negative carotid artery obstruction (atheroma plaque size <70%). The age group >60 years old ( p = 0.06), cup/disc ratio >0.6 ( p = 0.06), and pseudophakic lens status were also factors with association with transient central retinal artery occlusion, although did not meet criteria for statistical significance. The only patient who experienced a recurrent episode of transient central retinal artery occlusion had diabetic macular edema, positive carotid Doppler test, and cup/optic disc ratio >0.6. Conclusion Transient central retinal artery occlusion is a rare adverse event that can appear in patients with retinal vascular disease receiving anti-vascular endothelial growth factor therapy. The atheroma plaque size and the number of prior injections can be associated with the severity of the event.

Hemodynamic parameters in the central retinal artery in active retinopathy of prematurity and their relationship with the central retinal vein

Purpose. To analyze the main hemodynamic parameters in the central retinal artery, as well as their relationship with hemodynamic indicators in the central retinal vein, depending on the stage and type of active ROP with the use of color duplex scanning. Material and methods. The 63 premature babies with various stages of active ROP and no signs of ROP were included in the study. The 55 children with active ROP included in the study were distributed according to the stages and type of disease course. All children were at the same gestational age at the time of examination – 37–38 weeks of postmenstrual age or at 6–11 weeks of life. For all these children were performed color duplex scanning of the vessels of the eye and orbit in the modes of color Doppler mapping and pulsed Doppler. Results. The study of the hemodynamic features of the central retinal artery in premature infants with active ROP showed that the progression of the disease was accompanied by a significant increase in blood flow velocity (Vsyst and Vdiast) with each subsequent stage of ROP. A higher index of peripheral vascular resistance is recorded in comparison with the non-progressive favorable type for children with an unfavorable course of the disease.The analysis of the ratio of the maximum blood flow velocities in the central retinal artery and central retinal vein made it possible to determine in which of the vessels the hemodynamic changes are most pronounced, depending on the stage and form of active ROP. Conclusion. Thus, there are statistically significant changes in such large vessels of the retinal bed as the central retinal artery and central retinal vein during active ROP. Color duplex scanning, having a significant diagnostic potential in assessing hemodynamic parameters, made it possible to obtain reliable information about the linear blood flow velocity and the state of peripheral resistance in the central retinal artery and their relationship with the central retinal vein. This information opens up prospects for improving the accuracy of predicting the nature of the course of the disease, especially i n the early stages. Keywords: color duplex scanning, active retinopathy of prematurity, hemodynamic parameters, central retinal artery, central retinal vein