Cone function in children with a history of preterm birth

Abstract

Color vision was examined by psychophysical tests and photopic color full-field electroretinography (ERG) in formerly preterm children, and compared with those of full-term children. In a prospective case-control study, 25 patients with a history of preterm birth 7-14 years of age were divided into three groups: group I, laser-treated retinopathy of prematurity [ROP] (n = 7); group II, spontaneously regressed ROP (n = 8); group III, no ROP (n = 10). Age-matched full-term born children comprised the control group (n = 8). Color vision was assessed by Fansworth D15 and Lanthony desaturated D15 tests. The cone function was tested using photopic full-field ERG. Besides the ISCEV standard stimuli, blue light on amber background was also used (S-cone ERG). The correlation between ERG parameters and prematurity or ROP was determined. We found no significant differences between any patient group and the control group in the results of the psychophysical tests, and implicit times of the ERG responses. The ERG b-wave amplitudes were significantly lower in group I (laser-treated ROP) compared to controls, for 2 of 4 stimulus conditions i.e. the standard (P = 0.028) and S-cone (P = 0.017) single flash ERGs. The general estimating equation model statistics found a significant effect of prematurity on the b-wave amplitudes (P = 0.025, standard, P = 0.014, S-cone ERG). A slightly reduced photopic ERG b-wave amplitude may be associated with prematurity.

Thyroid Activating Enzyme, Deiodinase II Is Required for Photoreceptor Function in the Mouse Model of Retinopathy of Prematurity

“…However, the effect of ROP on color vision in children has contrasting findings with some studies reporting color vision deficits [19][20][21]43 in infants with severe ROP whereas other studies indicate negative findings. 22,44,45 Nonetheless, similar to our data with the Dio2 KO animals, ERG studies have demonstrated delayed cone responses and foveal thinning in children with a history of ROP. 20,21,23,43,46 Thyroid hormone deficiency in preterm infants results in reduced contrast sensitivity, slow blueyellow and red-green color vision processing, suggesting that thyroid hormone levels need to be taken into consideration for ROP development.…”

Reduction of Rod and Cone Function in 6.5-Year-Old Children Born Extremely Preterm

“…The results of our study are in line with those of several ffERG studies, revealing a retinal dysfunction in infants and children who were born preterm. 13,[26][27][28][29][30][31][32][33] However, most of these studies reported a predominantly negative association with rod function, [27][28][29]31,32 and Fulton et al 32 have described that cone function was less affected by preterm birth than was rod response. In contrast, our study found that cone function was also reduced, which might be explained by the extreme prematurity of the study group, resulting in an early arrest of the development of cone photoreceptors and bipolar cells.…”

“…Several ERG studies of prematurely born infants and children reveal different conclusions regarding the association with GA, ROP, and treated ROP. [26][27][28][29][30][31][32] However, the studies are not comparable because the GA range, the number of preterm children, the age at examination, and the ERG methods were all different. Åkerblom et al 26 reported a positive correlation between the rod and cone response and increasing GA in preterm children with a GA of between 22 and 32 weeks at birth.…”

“…27 Furthermore, both rod dysfunction and cone dysfunction are seen in infants with treated ROP. 29,30 Our study encompassed a homogenous group of children, born within a very narrow range of GA. Furthermore, a large number (35 of 52 [67%]) of the preterm children had ROP diagnosed during the neonatal period, and only 6 children had received laser therapy for ROP (1 eye also received cryotherapy).…”

Delayed luminance and chromatic contrast sensitivity in infants with spontaneously regressed retinopathy of prematurity

“…Whether ROP impairs color vision is more controversial, with a few studies reporting higher incidence of color deficits in children with severe ROP, compared to preterm controls [19,25,26] and other studies failing to replicate this finding, even with severe ROP [20,23,27,28]. These studies used pseudoisochromatic plates or hue-matching tests designed as rapid screening tests for inherited cone anomalies (i.e., protanopia and deuteranopia) and are not psychophysical assessments of color sensitivity.…”