Purpose
To investigate the long-term changes in axial length and refraction and the characteristics of Fourier domain-optical coherence tomography in children with syndrome of myelinated retinal nerve fibers (MRFN), axial myopia and amblyopia.
Methods
Ten children (4.40±2.22 years, 4 boys and 6 girls) with the syndrome of MRNF, axial myopia and amblyopia were recruited in this prospective self-controlled study. Each eye underwent routine ophthalmic examinations, including axial length (AL), cycloplegic refraction, best-corrected distance visual acuity (BDVA), simultaneous perception, cover test, corneal curvature, anterior segment and fundus examinations. Spectacles or rigid gas permeable contact lenses (RGP) were used for refractive correction. Part-time occlusion therapy (6-8 hours per day) was employed for amblyopia. Lesion areas and macular thicknesses were examined only on the final visit. Statistical analysis was performed using SPSS 19 software. Cut-off P values were 0.05.
Results
The follow-up periods ranged from 1.17 to 9.75 years (mean 4.00±2.40 years). No one dropped out. Two affected eyes had a final BDVA of 20/25; four had 20/60 or better; eight were better than 20/200 and one was worse than 20/200. Nine fellow eyes were 20/25 or better. Six children had normal simultaneous perception. AL and spherical equivalent were both significantly different over time and between groups (P<0.0001), but no time*group interaction effect (P>0.05) was observed. The differences in the corneal curvature, annual mean rate of axial elongation (AMR-AE), annual mean rate of refractive growth (AMR-RG), foveal thickness and parafoveal thickness between the two groups were not significant (P>0.05). The mean perifoveal thickness in the affected eyes was significantly higher than that of the control eyes (P=0.047). In the treatment group, the occlusion dose correlated positively with final BDVA (R=0.764, P=0.016) but did not correlate with the AMR-AE, or AMR-RG (P>0.05).
Conclusions
The affected eyes and the fellow eyes show similar developmental processes in AL and refraction. Part-time occlusion therapy may have no effect on axial elongation or refractive growth but may have positive effect on visual improvement.