Comparison of Cycloplegic and Manifest Refraction in Children and Adolescents

Purpose: To determine the relation between manifest refractive error and cycloplegic refractive error in children and adolescents in Campinas - SP, Brazil, and to compare the results with previous published studies. Methods: Dynamic and static retinoscopy was performed in children and adolescents. To obtain cycloplegia, three drops of 1% cyclopentolate was instilled in each eye every 5 minutes. Maximum cycloplegic effect was achieved after 45 minutes. The working distance for retinoscopy was 67 cm. During retinoscopy, the room was dimly illuminated, and patients were instructed to look at a spot of light at a distance of 6 m. Retinoscopic findings were measured before and after cycloplegia. Results: Two hundred and twenty-two (222) eyes of one hundred and eleven (111) children and adolescents were included. The average age of the participants was 10 years (range 4 to 15 years); 57 (51%) were girls, and the other 54 (49%) were boys. The most common refractive error in younger children was hyperopia, whereas myopia was the most common error in older children. The value of the latent error (the difference between cycloplegic and non-cycloplegic error) increased with hyperopia, especially in younger patients. The value decreased gradually in patients with moderate hyperopia and myopia. Conclusion: The cycloplegic refraction is more sensitive than the subjective one to measure refractive error at all age groups especially in children and young adults. The cyclo-refraction technique is highly recommended to precisely measure the refractive error in momentous conditions such as refractive surgery, epidemiological research, and amblyopia.