Abstract
Purpose: To explore associations between refractive error and foveal hypoplasia in infantile nystagmus syndrome (INS).Methods: Fifty participants with INS (albinism n=33, non-albinism infantile nystagmus [NAIN] n=17) age 4-48 years were recruited. Cycloplegic refractive error and LogMAR acuity were obtained. Spherical equivalent (SER), most ametropic meridian (MAM) refractive error and better eye acuity (VA) were used for analyses. High resolution spectral-domain optical coherence tomography (SD-OCT) was used to obtain foveal scans which were graded using the Foveal Hypoplasia Grading Scale. Associations between grades of severity of foveal hypoplasia and refractive error and VA were explored. Results: Participants with more severe foveal hypoplasia had significantly higher MAMs and SERs (Kruskal-Wallis H p=0.005 and p=0.008 respectively). There were no statistically significant associations between foveal hypoplasia and cylindrical refractive error (Kruskal-Wallis H p=0.144). Analyses demonstrated significant differences between participants with albinism or NAIN in terms of SER and MAM (Mann-Whitney U p=0.001). There were no statistically significant differences between astigmatic errors between participants with albinism and NAIN. Controlling for the effects of albinism, results demonstrated no significant associations between SER and MAM and foveal hypoplasia (partial correlation p>0.05). Poorer visual acuity was statistically significantly associated with more severe foveal hypoplasia (Kruskal-Wallis H p=0.001) and with a diagnosis of albinism (Mann-Whitney U p=0.001). Conclusions: Increasing severity of foveal hypoplasia is associated with poorer VA, reflecting reduced cone density in INS. Individuals with INS also demonstrate a significant association between more severe foveal hypoplasia and increasing hyperopia. However, in the absence of albinism there is no significant relation between refractive outcome and degree of foveal hypoplasia suggesting that foveal maldevelopment in isolation does not significantly impair the emmetropisation process. It is likely that impaired emmetropisation evidenced in the albinism group may be attributed to the whole eye effect of albinism.
| Original language | English |
|---|---|
| Journal | Investigative Ophthalmology and Visual Science |
| Volume | 54 |
| DOIs | |
| Publication status | Published (in print/issue) - 21 Mar 2013 |
Bibliographical note
Reference text: 1. Fu VL, Bilonick RA, Felius J et al. Visual acuity development of children with infantile nystagmus syndrome. Invest Ophthalmol Vis Sci. 2011;14:1404-1411.2. Self J, Lotery A. A review of the molecular genetics of Congenital Idiopathic Nystagmus (CIN). Ophthalmic Genet. 2007;28:187-191.
3. Edmunds RT. Vision in albinos. Arch Ophthalmol 1949;2:755–767.
4. Summers CG. Vision in albinism. Trans Am Ophthalmol Soc. 1996;94:1095–1155.
5. Wildsoet CF, Oswald PJ, Clark S. Albinism: its implications for refractive development. Invest Ophthalmol Vis Sci. 2000;41:1–7.
6. Mota A, Fonseca S, Carneiro A et al. Isolated Foveal Hypoplasia: Tomographic, Angiographic and Autofluorescence Patterns. Case Reports in Ophthalmological Medicine. (2012). Article ID 864958, 3 pages.
7. Thomas MG, Kumar A, Mohammad S et al. Structural grading of foveal hypoplasia using spectral-domain optical coherence tomography a predictor of visual acuity? Ophthalmology 2011;118:1653-60.
8. Recchia FM, Carvalho-Recchia CA, Trese MT. Optical coherence tomography in the diagnosis of foveal hypoplasia. Arch Ophthalmol. 2002 Nov;120(11):1587-8.
9. Meyer CH, Lapolice DJ, Freedman SF. Foveal hypoplasia in oculocutaneous albinism demonstrated by optical coherence tomography. Am J Ophthalmol. 2002 Mar;133(3):409-10.
10. Weiss AH, Kelly JP. Acuity Development in Infantile Nystagmus. Invest Ophthalmol Vis Sci 2007;48:4093-4099.
11. Casteels I, Harris CM, Shawkat F et al. Nystagmus in infancy. Br J Ophthalmol 1992;76:434-437.
12. Khanna S, Dell’Osso LF. The diagnosis and treatment of Infantile Nystagmus Syndrome (INS). The Scientific World Journal 2006;6:1385-1397.
13. Wang J, Wyatt LM, Felius J et al. Onset and Progression of with-the-rule astigmatism in Children with Infantile Nystagmus Syndrome. Invest Ophthalmol Vis Sci 2010;.51:594-601
14. Grosvenor T. Etiology of astigmatism. Am J Optom Physiol Opt. 1978;55:214–218.
15. Mahon G, McCrudden J. Optical coherence tomography (OCT)- is it simply pattern recognition? Optometry in Practice 2011;12:63-75.
16. McAllister JT, Dubis AM, Tait DM, et al. Arrested development: high-resolution imaging of foveal morphology in albinism. Vision Res. 2010;50:810-817.
17. Harvey PS, King RA, Summers CG. Spectrum of foveal development in albinism detected with optical coherence tomography. J AAPOS. 2006;10:237–242.
18. Smith EL 3rd, Ramamirtham R, Qiao-Grider Y, Hung LF, Huang J, Kee CS, Coats D, Paysse E. Effects of foveal ablation on emmetropization and form-deprivation myopia. Invest Ophthalmol Vis Sci. 2007;48:3914-3922.
19. Huang J, Hung LF, Smith EL 3rd. Effects of foveal ablation on the pattern of peripheral refractive errors in normal and form-deprived infant rhesus monkeys (Macaca mulatta). Invest Ophthalmol Vis Sci. 2011;16:6428-6434.
20. Donatien P, Jeffrey G. Correlation between rod photoreceptor numbers and levels of ocular pigmentation. Inves Ophthalmol Vis Sci. 2006;43:1198-1203.
21. Mohammad S, Gottlob I, Kumar A et al. The functional significance of foveal abnormalities in albinism measured using spectral-domain optical coherence tomography. Ophthalmology. 2011 Aug;118(8):1645-52. doi: 10.1016/j.ophtha.2011.01.037. Epub 2011 May 12
Keywords
- albinism
- refractive error
- emmetropisation
