The aim of this study is to evaluate the visual function of children with albinism.

A total of 84 children with albinism (168 eyes) and 25 healthy children (50 eyes) who visited the ophthalmology department of Beijing Children′s Hospital affiliated with Capital Medical University from February 2015 to May 2021 were enrolled. There were 71 males (142 eyes) and 38 females (76 eyes) with an average age of (35.6±27.5) months (ranged from 2 to 167 months). According to disease diagnosis, children with albinism are classified as the albinism group, while healthy children are classified as the control group. The routine eye examinations, optical coherence tomography (OCT), and single channel flash visual evoked potential (F-VEP) testing on the affected child were performed, and the type of genetic mutation disease through genetic testing was determined. The best corrected visual acuity, F-VEP P2 wave latency, amplitude and other quantitative data are expressed as ±s, and compared by independent sample t-test for inter group. The correlation between F-VEP indicators and visual acuity, onset time, and grading of macular fovea dysplasia was used to analyze by Pearson or Spearman correlation analysis

There were 54 males (108 eyes) and 30 females (60 eyes) in the albinism group, and 17 males (34 eyes) and 8 females (16 eyes) in the control group. The difference was not statistically significant difference between them(χ²=0.12, P>0.05). The average age of the albinism group and the control group were (39.05±32.20) months and (32.20±22.70) months, respectively. After rank sum test, the difference was not statistically significant (Z=-0.49, P>0.05). 60 cases completed genetic testing. Among them, there were 3 cases with negative, 48 cases of cutaneous albinism (OCA), 3 cases of simple ocular albinism (OA), 6 case of HPS, accounting for 5.00%, 80.00%, 5.00%, 10.00%, respectively. All genetic mutations in the patients in this study were pathogenic mutations. 30 cases (60 eyes) of children with albinism completed visual acuity examinations. The naked eye visual acuity of the right eye, left eye, and both eyes were (0.21±0.19)(logarithm of the minimum angle of resolution, logMAR), (0.21±0.20)logMAR, and (0.21±0.19)logMAR, respectively. The corrected visual acuity for the right eye, left eye, and both eyes were (0.33±0.27) logMAR, (0.31±0.24)logMAR, and (0.32±0.25)logMAR, respectively. After correction, the visual acuity slightly improved, and the differences compared to naked eye vision were statistically significant (t=-3.77, -4.29, -5.64; P<0.05). 60 children (120 eyes) with albinism completed refractive tests, with an average spherical equivalent of (+ 1.09±3.13)D. Among them, 57 cases (113 eyes) had astigmatism, with an average spherical equivalent of (-2.37±1.19)D. 16 children (32 eyes) in the normal control group completed visual acuity examinations, and the average visual acuity in the right eye was (0.80±0.20)logMAR. The average visual acuity of the left eye was (0.83±0.18)logMAR. The latent periods of the right and left eyes of 68 children with albinism (136 eyes) were (118.25±37.39)ms and (117.63±32.33)ms, respectively. The incubation periods of the right and left eyes in the control group were (108.68±15.05)ms and (111.89±17.61)ms, respectively, and there was no statistically significant difference between them (t=1.24, 0.84; P>0.05). The amplitudes of the right and left eyes of children with albinism are (17.39±9.08)uV and (15.55±8.75)uV, respectively. The amplitudes of the right and left eyes in the control group were (17.39±9.08)uV and (15.55±8.75)uV, respectively. The amplitude of the control group was greater than that of the albinism group, with statistical significance (t=-2.1, P<0.05). 36 patients (72 eyes) completed OCT examination. The grading of macular dysplasia was normal, with 2 cases (4 eyes), 3 cases (6 eyes), 6 cases (12 eyes), 13 cases (25 eyes), and 13 cases (25 eyes), respectively. There is a negative correlation between the grading of macular dysplasia and corrected visual acuity, with statistical significance (r=-0.60, P<0.05), and a negative correlation with FVEP amplitude, with statistical significance (r=-0.34, P<0.05).

Among 84 children with albinism, OCA is more common, astigmatism is more common in both eyes, and visual impairment is significant. After correction, mild improvement can be achieved. The abnormal manifestation of using single channel F-VEP is mainly the asymmetry between the two eyes during the P2 amplitude. The corrected visual acuity of both eyes is positively correlated with the amplitude of F-VEP. Patients with albinism have significantly underdeveloped macular fovea, which is negatively correlated with the amplitude of F-VEP. The evaluation of visual function development in children with albinism requires comprehensive consideration of factors.