Comparison of epidemiologic factors and eye manifestations of twin children with controls.

PURPOSE: The present study was aimed to compare the epidemiological and ocular findings of twin children in comparison with non- twin age matched individuals as their control. METHODS: In this cross sectional study, a total of 90 twins (180 cases) were compared with 182 non- twin matched children. All the study participants were examined by a comprehensive ophthalmic examination including measurement of the best corrected visual acuity (BCVA), cycloplegic refraction, ocular deviation, strabismus as well as the anterior and posterior ophthalmic examinations. Demographic information of children were collected by using an organized questionnaire. Monozygotic twins were considered if there were similarity of their phenotypic characteristics and gender, otherwise the twins were considered as dizygotic. RESULTS: The mirror- image twins (MIT) was defined according to the laterality of symmetrical ocular characteristics of twins. In this study, the mean age of the study participants was 7.08±4.42 and 7.58±3.99 years in twins and non-twins groups, respectively (P=0.253). Among the twins, 27 (30%) were monozygotic. Refractive form of MIT was seen in 5 twins (2.8%). The spherical refractive error was more hyperopic in twins compared to non- twins (P=0.041). BCVA in the twin group (0.07±0.16LogMAR) was significantly worse than non-twins (0.03±0.08LogMAR, P < 0.001) and higher percentage of them were amblyopic (37.2% versus 10.4%, P=0.005). Twin and controls had strabismus in 17.2% and 1.6%, respectively (P < 0.001). Regarding the comparison between mono- and dizygotic twins, more significant percentage of monozygotic twins had amblyopia (P=0.004) and strabismus (P=0.047). Multivariate analysis showed significant correlation among low gestational age and female gender, low birth weight and seizure. CONCLUSION: Female sex, less gestational age, low birth weight, amblyopia and strabismus were significantly higher in twins. Therefore, it is important to check their refractive error, amblyopia and strabismus to prevent their further complications.

Scientific Publications and Subject Clusters in the Field of Glaucoma: A Scientometric Analysis.

Purpose: To analyze the glaucoma research in the Web of Science (WoS) and Scopus to determine the top features, trends, and subject clusters. Methods: In this scientometric study, all glaucoma publications in Scopus and WoS were analyzed based on various characteristics such as authors, journals, and co-word analysis. Data analysis was conducted using both Excel and VOSviewer. Results: A gradual increase in the publication rate was found for articles in the field of glaucoma in both Scopus and WoS databases. In this regard, most publications were conducted in the USA and the University of California System. The co-word network was constituted of five clusters, including glaucoma, intraocular pressure, open-angle glaucoma, visual acuity, and optic disc. It showed that the top 10 highly cited articles were more addressed by epidemiologic studies. Conclusions: The findings of this study had a more precise vision of the previous research on the field of glaucoma. It also provided the possibility to discover hidden patterns and emerging events of a subject by explaining the most essential aspects of research and identifying the areas that need more research. The findings could be useful for authors and health policymakers in academia and countries.