Causes of Blindness and Low Vision in Schools for Students With Visual Impairments in Tehran
Bibliographic record
Abstract
Introduction: Childhood visual impairment is a global concern. We aimed to identify the major causes of childhood visual impairment in schools for students with visual impairments in Tehran, Iran. Methods: This cross-sectional study was conducted on students attending two schools for students with visual impairments in Tehran. All students or their guardians were interviewed to record their past medical history. Students underwent comprehensive ocular examinations, including assessment of presenting visual acuity, eye fixation status, color vision, external ocular exam, and examinations of anterior and posterior ocular segments. The classification of visual impairment was conducted based on the definitions provided by the World Health Organization International Classification of Diseases, and the exact cause of visual impairment was recorded. Results: A total of 134 students, whose average age was 13.52 ± 2.9 years (range, 7 to 18 years) and who were primarily female (56.7%), participated. More than 82.8% of participants had blindness (1.3 to 3.1 LogMAR, < 3/60), 4.4% had severe visual impairment (1.0 to 1.3 LogMAR; 3/60-6/60), and 12.8% had moderate visual impairment (0.48 to 1.0 LogMAR; 6/60-6/18). The retina (47.1%), optic nerve (17.9%), and whole globe (10.5%) were the most affected anatomical sites, with Leber's congenital amaurosis (a hereditary retinal disorder) being the most prevalent diagnosis (27.8%), followed by optic nerve atrophy (17.9%), congenital glaucoma (9.7%), phthisis eye (5.2%), and microphthalmos (5.2%). We found parental consanguinity in 68.42% of cases with hereditary retinal disorders. Discussion: In the current study, hereditary retinal disorders were among the most prevalent causes of visual impairment, which can be attributed to the high rates of consanguineous marriages in Iran. Implications for Practitioners: The current findings highlight the need to provide an educational program to raise awareness in our society about the hereditary causes of visual impairment, particularly as a potential result of autosomal recessive genetic disorders.
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How this classification was reachedexpand
Full frame distilled prediction
Teacher imitationNot calibrated prevalence, not ground truth. Human validation pending. Learned from the 10,348 direct Codex labels and 10,348 direct Gemma labels. Candidate is the union of thresholded teacher heads; consensus is their intersection. These outputs are machine_predicted_unvalidated and are not human labels or direct frontier model labels.
Codex and Gemma teacher scores by category
| Category | Codex | Gemma |
|---|---|---|
| Metaresearch | 0.002 | 0.000 |
| Meta-epidemiology (narrow) | 0.000 | 0.000 |
| Meta-epidemiology (broad) | 0.001 | 0.000 |
| Bibliometrics | 0.002 | 0.001 |
| Science and technology studies | 0.000 | 0.000 |
| Scholarly communication | 0.000 | 0.000 |
| Open science | 0.000 | 0.000 |
| Research integrity | 0.000 | 0.001 |
| Insufficient payload (model declined to judge) | 0.000 | 0.000 |
Machine scores (provisional)
The two teacher heads of the student model, read on this work. A score orders the frame for review; it never asserts a category, and the validation status ships verbatim with every row.
Baseline scores from an immature model (maturity gate not passed, 7 training rounds). Scores rank; they never assert a category.
score_only:v0-immature-baseline · verbatim from the scoring run: score_only means the number may rank works, and no category label ships from itClassification
machine, unvalidatedMachine predicted; a candidate call from one teacher head, not a consensus.
How this classification was reached, model by model and score by score, is at the end of the page under "How this classification was reached".