Abstract
Purpose :
Prior study of macular structure and visual acuity provides evidence that preterm birth alters the late maturing central retina. The aim of the present project is to use the multifocal electroretinogram (mfERG) to study the topography of cone mediated activity in the central retina of subjects with a history of preterm birth.
Methods :
In our ongoing study, mfERG responses from former preterms (n=29, median age 15.4 years) and term born controls (n=29, median age 23.4 years) were recorded. The former preterms included subjects with a history of mild untreated ROP (n=17), more severe ROP that had required laser ablation of the peripheral avascular retina (n= 2), and those who never developed ROP (n = 10). The stimuli were an array of 103 scaled hexagons subtending 43° concentric with the fovea. The responses were analyzed as ring averages. The response densities (“amplitude”) of the P1 component of the former preterms were compared to those of the controls.
Results :
In all groups, the amplitude of P1 was largest at the center (Ring 1) and decreased gradually with eccentricity. The smallest amplitude was at the most peripheral ring (Ring 6). Analysis of variance showed that P1 amplitude varied significantly with group and eccentricity (p<0.001). The amplitudes in the former preterms were significantly smaller than in the controls. The greatest difference between former preterms and controls was in Ring 1. P1 amplitude was significantly lower than normal, even in those who never developed ROP. The deficit in P1 was greatest in those who had severe ROP that required treatment . P1 amplitudes were similar in those who never had ROP and those who had mild ROP that did not require treatment.
Conclusions :
Preterm birth alone is associated with mild but statistically significant deficits in central retinal function. This result complements the reported thickening of post-receptor retinal laminae in the central retina. The greater deficits in those who had treated ROP may be due not only to dysfunction of the post-receptor retina but also to the recently reported adaptive optics evidence of disrupted cone photoreceptors.
This is an abstract that was submitted for the 2016 ARVO Annual Meeting, held in Seattle, Wash., May 1-5, 2016.