Aims To discern treatable and preventable causes of childhood blindness by evaluating the aetiologic factors, and to compare the distribution of the most commonly affected anatomic sites of severe visual impairment (SVI) with our previous published data.

Methods The charts of 11 871 patients followed between June 2002 and May 2014 were reviewed retrospectively, and 695 patients (5.9%) who had SVI or blindness in accordance with WHO criteria were enrolled. The results of ophthalmologic examinations and coexistence of any systemic disease were documented and checked against our published clinic data concerning the aetiology of childhood blindness before 2002. χ² test was used for statistics.

Results Mean age was 47.0±51.9 months (median: 24 months). Cortical visual impairment (CVI) was present in 212 cases (30.5%) and 20.3% of those had a history of premature birth. The most common anatomic sites of SVI were retina (24.6%) and crystalline lens (17.1%). When compared with our previous data, we found a significant increase in the prevalence of CVI (p=0.046) and decrease in the frequency of SVI due to uveal disorders (p<0.001). Prevalence of blindness secondary to retinopathy of prematurity reduced by a third (p=0.280), and a significant decrease in aphakia-related SVI (p=0.028) was achieved within the last decade.

Conclusions The prevalence of CVI was found to be relatively increased due to the significant reduction in the frequency of preventable causes of SVI. Furthermore our clinical practice for visual rehabilitation in aphakia has resulted in a considerable decrease in SVI in the last decade.