Introducing a new method of retinoscopy for refraction of infants and young children: The "Mirza" tele lens retinoscopy

Abstract

Purpose: This study aimed to evaluate the refractive error of the uncooperative infants and children with the new method of retinoscopy called the tele-lens ("Mirza") retinoscopy.

Methods: In the "Mirza" tele-lens retinoscopy, the examiner placed the trial lenses in 1/3 distance between the tested eye person and peephole of the retinoscope (22.2 cm far from the spectacle plane). First, the optical calculations were done to find the correction factors for this new method of retinoscopy. Second, the dry standard and "Mirza" tele-lens retinoscopy were performed in 78 eyes from 39 children aged 7-12 years with good cooperation and next, the procedure was repeated using cyclopentolate drops and then the results of the two methods were compared, and at the end, the dry "Mirza" tele-lens retinoscopy was done in the 60 eyes of 31 uncooperative infants with a mean age of 21.85 ± 8.79 months for evaluating the feasibility of the "Mirza" tele-lens retinoscopy procedure. The intraclass correlation coefficient (ICC) and Bland-Altman plot for assessment of agreement between the findings of two retinoscopic methods in dry and cyclo conditions were used.

Results: The comparison between the dry standard and "Mirza" tele-lens retinoscopic results with means of 1.39 ± 1.43 and1.36 ± 1.39, respectively were not statistically significant (p > 0.05). Besides, comparing the mean cycloplegic results of two methods (standard vs. "Mirza" tele-lens), the difference was not statistically significant (2.37 ± 1.44 vs. 2.41 ± 1.37) (p > 0.05). Moreover, Two-way repeated measures ANOVA revealed no significant retinoscopy method × use of drops interaction (P = 0.103) in comparing two methods of the standard and "Mirza" tele-lens retinoscopy. ICC results indicated high agreement between two methods in both dry (ICC = 0.993) and cyclo (ICC = 0.989) conditions.

Conclusions: The "Mirza" tele-lens retinoscopy method can be performed with satisfactory results in infants and children who do not cooperate for the standard procedure of measuring the refractive errors.

Keywords: Infants; Refraction; Retinoscopy; Uncooperative children.

Figure 1

The “Mirza” tele-lens and standard retinoscopy. In A, the child’s reaction to approaching the trial lens in standard retinoscopy procedure was showed. In B, the trial lens magnification from its position farther from the spectacle plate was illustrated. In C, the “Mirza” tele-lens retinoscopy was performed by placing the trial lens at 22.2 cm far from the child’s spectacle plane.

Figure 2

The effect of working distance changes from 22.2 to 3 cm back and forth on the “Mirza” tele-lens retinoscopy.

Figure 3

Bland–Altman plots showing the agreement of the dry (A) and cycloplegic (B) results taken with the standard and “Mirza” tele-lens retinoscopic methods. The solid line indicates the mean difference, and the dotted lines indicate 95% limits of agreement.