Features of the Foveal Avascular Zone in Children with Active Retinopathy of Prematurity According to Optical Coherence Tomography in Angio Mode

The purpose — to study the features of the foveal avascular zone (FAZ) in children with active retinopathy of prematurity according to the data of optical coherence tomography in angio-mode.

Patients and methods. OCT-A was performed on 37 premature infants (37 eyes) with active ROP: at stages 1–2 — in 14 eyes (8 — with a favorable current type, 6 — with an unfavorable current), at stage 3 — in 16 eyes (6 — with a favorable type, 10 — with unfavorable), with aggressive posterior ROP — in 7 eyes (4 — at the stage of early clinical manifestations, 3 — at the stage of manifestation). Patients with stages 1 and 2 of active ROP were combined into one group due to similar findings. The control was the data of OCT-A performed on 10 premature infants without signs of ROP.

Results. At 1–2 stages with a favorable type in children with a somatic state of moderate severity in the FAZ area, statistically significant differences in comparison with the control parameters were not determined. In children with a severe condition, FAZ was significantly expanded, which was accompanied by a significant decrease in the density of capillaries in the fovea. With an unfavorable type, a significant decrease in the size of the FAZ was noted, as well as a slight decrease in the density of the capillaries of the superficial plexus in the fovea. At stage 3 with a favorable type, an expansion of the FAZ, a decrease in the density of capillaries in the fovea in the superficial and deep plexus were recorded, and the values of the density of capillaries in the parafovea were slightly increased. At 3 stages with an unfavorable course in children born at a gestational age of 29–32 weeks, the FAZ was expanded. In children born at a gestational age of 25–28 weeks, a significant decrease in the size of the FAZ was recorded in comparison with children with a long gestation period, as well as those with a favorable course of stage 3. At the stage of early clinical manifestations of the posterior aggressive ROP, the FAZ was absent; vessels grew into it, which formed shunts and zones of intraretinal neovascularization in the form of “tangles”. At the stage of manifestation of the posterior aggressive ROP, a gross violation of the architectonics of the microvasculature was determined. As at the stage of early clinical manifestations, FAZ was absent; shunt vessels grew into it.

Conclusion. The OCT method in angio-mode has showed high information content in studying the features of the foveal avascular zone in children with various forms, stages and types of active ROP. The characteristics of FAZ with an unfavorable type of the disease are of the greatest value for clinical practice. Their identification at the early stages of the pathological process will make it possible to timely determine the correct tactics and carry out the necessary treatment.

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