[The prevalence of cerebral visual impairment among high-risk visually impaired children in Hungary]

Introduction: In cerebral visual impairment (CVI), the disturbance in visual function is not due to a condition of the eyeball but to a malfunction in the neural processing of visual information. The prevalence of cerebral visual impairment is unknown in Hungary. Still, it is essential to initiate a professional debate, as early-onset visual impairment impairs later mental and physical health and social advancement and creates a burden on society. Objective: A pilot study was carried out to assess the prevalence and incidence of cerebral visual impairment, either concomitant or independent of ocular visual impairment, in a cross-sectional survey of the School for the Visually Impaired in Budapest. Methods: We used special education methods to investigate the characteristics of cerebral visual impairment among low-vision children at high risk for cerebral visual impairment. We compared the gender and age distribution of students with and without cerebral visual impairment symptoms, data on birth conditions, and ophthalmological diagnosis. Results: Between 2021 and 2024, data from 120 students were analyzed, of whom 58 students (48.3%) had a history of increased risk of cerebral visual impairment. In the group at high risk for cerebral visual impairment, 33 (56.9%) pupils were found to have cerebral visual impairment abnormalities detected by teachers of visual impairments, while 4 (6.9%) had cerebral visual impairment in an ophthalmological report. Where teaching of visually impaired children methods confirmed cerebral visual impairment in the presence of high risk of cerebral visual impairment, the proportion of boys was higher compared to the non-cerebral visual impairment subgroup (66.7% vs. 36.0%, p = 0.020). Within the high-risk group, birth weight and gestational age did not differ among the cerebral visual impairment and non-cerebral visual impairment groups. Discussion: In children with a declared visual impairment, the teaching of visually impaired children method is the appropriate method for detecting cerebral visual impairment, while an ophthalmological examination may raise suspicion of cerebral visual impairment. As in other countries, cerebral visual impairment is significantly underdiagnosed in Hungary. Our measurements confirmed that boys were overrepresented in the cerebral visual impairment group, but the main etiological role of prematurity was not confirmed. Conclusion: In the high-risk group, teaching of visually impaired children methods are necessary in addition to ophthalmological examination to prove the presence of cerebral visual impairment. Targeted development as early as possible is a pledge to improve visual function. Further studies are needed to assess the prevalence of the condition in Hungary. Orv Hetil. 2025; 166(11): 421–426.