Posters

Influence of intensive nearwork on refractive, biometric and topographic changes in last year Portuguese medical students: one-year longitudinal study

Poster Details

First Author: S.Torres da Costa PORTUGAL

Co Author(s):    S. Sousa   J. Meira   F. Falcão-Reis   M. Falcão           

Abstract Details

Purpose:

Educational level and time spent in nearwork activities have been identified as risk factors for myopia progression. Medical students represent a specific group of university students who spend a lot of time in intensive nearwork. In their last year, these students have a final examination for which students start studying six to twelve months before. The purpose of this study is to evaluate the refractive, biometric and topographic changes in the last year Portuguese medical students after a long period of intensive nearwork and to determine the reversibility of these changes after 6 months.

Setting:

Centro Hospitalar Universitário de São João, Porto, Portugal.

Methods:

A one-year longitudinal cohort study was performed. Data collected consisted in noncycloplegic automated refraction measures, axial length, anterior chamber depth, anterior chamber volume, and corneal volume, corneal keratometry and thickness obtained in different points. Ophthalmological evaluations were performed 6 months before the students’ final exam and, then, repeated up to a month after the exam and 6 months later. Only right eye data were used. There was no significant difference between the mean refractive error of the right eye versus left eye.

Results:

Twenty-five last year medical students, 20 females and 5 males, with a mean age of 24,44 years, were included. At the beginning of the study, the mean spherical equivalent was -1,57 ± 1,29 D. In the 2nd visit, it was -1,73 ± 1,44 D (p=0,055) and, in the 3rd visit, it was -1,40 ± 1,39 D (p=0,331). In the 1st, 2nd and 3rd visits, the axial length was 23,91 ± 0,99 mm; 24,01 ± 0,98 mm (p=0,001) and 23,94 ±1,03 mm(p=0,414), respectively. Corneal thickness and posterior surface corneal keratometry in the steepest axis decreased significantly at the 2nd visit (p=0,001). No other significant changes were observed.

Conclusions:

This is the first study about the variation of refraction, biometry, keratometry and corneal thickness in last year Portuguese medical students after a long period of intensive nearwork. Myopia is a condition with increasing prevalence in some countries especially among individuals with a higher level of education. Understanding the pathophysiology of myopia in this group of individuals is essential for the development of control strategies. In the particular case of university students, we do not recommend the actualization of their contact lenses or eyeglasses immediately after a period of intensive nearwork since this change is expected to be transient.

Financial Disclosure:

None