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[Keratoconus screening in a Lebanese students' population]
N Waked1, A M Fayad, A Fadlallah
1Service d'Ophtalmologie, Université Saint-Joseph, Hôpital Hôtel-Dieu de France, Beyrouth, Liban. wakednaji@yahoo.com
Objective:
Screening for keratoconus and potential risk factors in a medical student population in Lebanon using anterior topography.
Population And Methods:
We randomly selected 110 medical students doing rotations in the Hôtel-Dieu de France hospital in Lebanon between November 2009 and February 2010. Ninety-two students agreed to participate in the screening protocol, which included a questionnaire and an anterior topography. The topography was performed using the placido disk Tomey(®) Topographic Modeling System TMS-4. The results were interpreted using the analysis programs supplied with the machine and by an experienced ophthalmologist.
Results:
Ninety-two students participated in the study (83.6%): 49 males (53.2%) and 43 females (46.8%). The mean age was 23.6±1 year. Fifty-eight students were ametropic (63.1%): 44 participants were myopic (47.8%), 40 had astigmatism (43.4%), and six were hyperopic (6.5%). Three students (six eyes) were diagnosed with keratoconus. The prevalence of keratoconus was 3.3%, of which 2.2% were already known cases. The prevalence of forme frustre keratoconus was 1.1%. Eleven students (12.1%) had a family history of keratoconus, only one was diagnosed with the disease. Atopy and eye rubbing were not found significantly related to keratoconus in this population.
Conclusion:
Keratoconus is a prevalent disease among our population of Lebanese medical students, which confirms the clinical impression that keratoconus is relatively frequent in Lebanon. Further studies need to be conducted on a larger and more representative sample to assess keratoconus prevalence and risk factors in Lebanon.
