Refractive state and visual acuity of children with extremely low birth weight at 3 years old in Japan.

PURPOSE: To investigate the refractive status and visual acuity of 3-year-old children with extremely low birth weight (ELBW). STUDY DESIGN: Retrospective cohort study. METHODS: We examined 161 children born between January 2009 and December 2014. The children were divided into five groups for evaluation of visual acuity and refraction: no retinopathy of prematurity (ROP), reverse ROP, photocoagulation (PC) zone II (ZII), PC (ZI), and PC (ZI + lens-sparing vitrectomy [vit]). RESULTS: Median (1st quartile, 3rd quartile) gestational age was 25 (24, 26) weeks. Median birth weight was 738 (588, 846) g. Spherical equivalence (SE) was +0.38 (-0.06, +0.75) diopters (D) in no ROP, +0.63 (-0.25, +1.34) D in reverse ROP, +0.38 (-0.75, +1.31) D in PC (ZII), -3.31 (-8.06, +0.16) D in PC (ZI), and -12.00 (-13.50, -4.50) D in PC (ZI+ vit) children. Best corrected visual acuity (BCVA) in log MAR was 0.15 (0.07, 0.26) in no ROP, 0.17 (0.10, 0.30) in reverse ROP, 0.22 (0.10, 0.38) in PC (ZII), 0.45 (0.22, 0.55) in PC (ZI), and 1.10 (0.82, 1.30) in PC (ZI+ vit) children. There was a significant correlation between SE and BCVA (r = -0.43, p < 0.0001). CONCLUSION: The no ROP, reverse ROP, and PC (ZII) groups showed no significant differences in SE or BCVA, accounting for 79.5% of ELBW children. SE and BCVA in the PC (ZI) and PC (ZI+ vit) groups were worse than in the other groups. The current results reveal a correlation between SE and BCVA.

Differential effects of black currant anthocyanins on diffuser- or negative lens-induced ocular elongation in chicks.

PURPOSE: To compare the inhibitory effects of 4 different types of black currant anthocyanins (BCAs) on ocular elongation in 2 different chick myopia models. METHODS: In the first model, diffusers were used to induce form vision deprivation. In the second model, negative (-8D) spherical lenses were used to create a defocused retinal image. Either the diffusers or the -8D lenses were placed on the right eyes of 8-day-old chicks for 4 days. Ocular biometric components were measured using an A-scan ultrasound instrument on the third day after application of either the diffusers or -8D lenses. Interocular differences (globe component dimensions of the right diffuser or eyes covered with -8D lenses minus those of the open left eyes) were considered to evaluate the effect of BCAs. The BCAs used were cyanidin-3-glucoside (C3G), cyanidin-3-rutinoside (C3R), delphinidin-3-rutinoside (D3R), and delphinidin-3-glucoside (D3G). Each anthocyanin was administered intravenously at a dose of 0.027 µmol/kg once a day for 3 days. RESULTS: Compared to the vehicle treatment, C3G and C3R treatments significantly reduced both differential increases (positive values of interocular differences) of the ocular axial length induced by diffusers or -8D lenses (diffusers; C3G, C3R, and control: 0.32±0.051 mm, P<0.05; 0.25±0.034 mm, P<0.01; and 0.52±0.047 mm, -8D lenses; C3G, C3R, and control: 0.25±0.049 mm, P<0.01; 0.17±0.049 mm, P<0.001; and 0.50±0.056 mm). In contrast, compared to vehicle treatment, D3R treatment significantly decreased the differential increases in the ocular axial length only in chicks with myopia induced by -8D lenses (D3R and control: 0.17±0.049 mm and 0.50±0.056 mm, P<0.001). D3G did not inhibit the differential increase in the ocular axial length induced by either diffusers or -8D lenses. CONCLUSIONS: This study showed that the 4 tested BCAs had different effects on the 2 different experimental models of myopia.

Effect of black-currant extract on negative lens-induced ocular growth in chicks.

AIM: To evaluate the effects of orally administered black-currant (BC) extract on the enlargement of globe component dimensions induced in chicks by wearing negative lenses. METHODS: Negative lenses (-8 D) were worn on the right eyes by 8-day-old chicks, and their fellow eyes acted as controls. BC extract and distilled water (vehicle control) were orally administered once a day for 3 days. To confirm the effect of BC anthocyanins (BCAs), they were intravenously administered once a day for 3 days. Dimensions of globe components of right eyes and fellow eyes were measured with an A-scan ultrasound instrument on the third day (day 4) after placement of the negative lenses. RESULTS: Orally administered BC extract significantly inhibited enlargement of vitreous-chamber depth, axial and ocular lengths in a dose-dependent manner when compared to controls. Intravenously administered BCAs also inhibited elongation of vitreous-chamber depth and axial length when compared to controls. CONCLUSIONS: This is the first evidence that BC extract and BCAs could inhibit enlargement of globe component dimensions in a negative lens-induced chick myopia model.

O potencial evocado por padräo reverso tipo steady-state / The steady-state pattern-reversal visual evoked response

Os autores apresentam uma descriçäo da técnica e os resultados normais de potencial visual evocado por padräo reverso (PVE-P) do tipo steady-state. O PVE-P steady-state diferencia-se no transient por utilizar uma frequencia de reversäo maior (6 Hertz) e, na interpretaçäo, valoriza-se mais amplitude do que a latência de resposta. Cinco tamanhos de quadrado diferentes (160,80,40,20 e 10 minutos de arco) säo apresentados em um monitor de 15 polegadas, a um metro do indivíduo. A média das amplitudes de resposta a cada um deles é calculada e checada por "Análise de Fourier". Um gráfico é feito a partir dos valores obtidos, a "Curva de Amplitude em Funçäo do Padräo", cuja confuguraçäo normal é a de um "U invertido", pois as melhores respostas geralmente acontecem para os padröes intermediários de 40 e 20 min. de arco.