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Influence of beta-adrenergic antagonists on tear secretion in children
Elzbieta Samochowiec-Donocik1, Bronisława Koraszewska-Matuszewska
1Department of Pediatric Ophthalmology, Medical University of Silesia, Ceglana 35, PL 40-952 Katowice, Poland. dzieci@kli-okul.katowice.pl.
Abstract:
The aim of the study was to compare the results of tear film volume, conjunctival and corneal state of children eyes both treated with beta-blocker and healthy ones. We have examined 40 eyes of 20 children at the age from 7 to 17 years. Group I - 20 glaucomatous eyes treated with 0.5% timolol twice daily during at least 12 months. Group II - 20 eyes of control age-matched group. Schirmer I test without anesthesia and lissamine green staining was performed to evaluate conjunctival and corneal surface. The values of Schirmer I test were: group I from 12 to 24 mm, the mean 17.06 +/- 1.78 mm and group II from 16 to 35 mm, the mean 29.3 +/- 2.67, p = 0.000004. Keratoepitheliopathy was observed in 4 eyes (20%) of group I and was rated as 3rd and 6th degree of Franck classification. In the group II, there were only single staining points classified as 1st degree noticed in 2 eyes (10%), p = 0.37. The long-term treatment with timolol causes a decrease in tear secretion in children, which can further generate keratoepiteliopathy. Therefore, we suggest application of the artificial tears in these patients.
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