Title: Enhanced Depth imaging optical coherence tomography of the choroid in eyes with high myopia and normal control group of kashmiri population

Authors: Dr Nazia Anjum, Prof. Junaid S. Wani, Prof. Afroz A. Khan, Dr Aalia Rasool, Dr Birjees Hakak

 DOI: https://dx.doi.org/10.18535/jmscr/v7i1.64

Abstract

 

Background: The purpose of this study was to examine the choroidal thickness (CT) of patients with high myopia using enhanced depth imaging optical coherence tomography(EDI-OCT) and compare with healthy subjects.

Methods: A case-control study of 107 eyes (57patients) with high myopia and 60 eyes (30 patients) of emmetropes. Choroidal imaging was performed using enhanced depth imaging spectral domain optical coherence tomography. CT was measured at, subfovea, 1mm and 3mm nasal and temporal to fovea.

Results: Statistical analysis was performed to evaluate CT at different locations and to correlate CT with axial length(AL) and spherical equivalent(SE).Mean SE was -12.07+-3.184D in eyes with high myopia and 25.66+-8.39D in normal control group. Mean AL was 26.68+-1.577mm in eyes with high myopia and 22.88+-0.56mm in normal control group. The CT at the subfovea was significantly thinner (mean+- standard error: 192.79+-51.61µm) for high myopic eyes compared to emmetropes (305.30+-60.11µm, p<0.001).Likewise, CT in high myopic group was significantly thinner than emmetropic control group at all locations (p for trend <0.001 for all locations).Choroid was thinnest at nasal 3mm location in both the myopic (136.46+-50.33µm) and emmetropic (289.02+-60.15 µm) groups. Choroid was thickest subfoveally in both the myopic (192.79+-51.61 µm) and emmetropic (305.30+-60.11µm) groups. CT was negatively correlated with SE and AL.

Conclusions: High myopic eyes have significantly thinner choroid compared to emmetropic eyes. Axial length and spherical equivalent are significant predictors of choroidal thickness.

Keywords: Myopia, OCT, Choroidal thickness.

References

  1. Duke-Elder’s Practice of Refraction, 10th Edition, P 53.
  2. Klaver CC, Wolfs RC, Vingerling JR, Hofman A, de Jong PT. Age specific prevalence and causes of blindness and visual impairment in an older population: the Rotterdam Study. Arch Ophthalmol 1998, 116: 653-58.
  3. Vongphanit J, Mitchell P, Wang JJ. Prevalence and progression of myopic retinopathy in an older population. Ophthalmology. 2002; 109: 704–11.
  4. Lim MC, Hoh ST, Foster PJ, Lim TH, Chew SJ, Seah SK, et al. Use of optical coherence tomography to assess variations in macular retinal thickness in myopia. Invest Ophthalmol Vis Sci. 2005; 46: 974–8.
  5. Curtin BJ, Karlin DB. Axial length measurements and fundus changes of the myopic eye. Am J Ophthalmol. 1971; 71: 42–53.
  6. Takano M, Kishi S. Fovealretinoschisis and retinal detachment in severely myopic eyes with posterior staphyloma. Am J Ophthalmol. 1999; 128: 472–6.
  7. Nickla D, Wallman J. The multifunctional choroid. ProgRetin Eye Res 2010; 29(2): 144–168.
  8. Hamzah F, Shinojima A, Mori R, Yuzawa M. Choroidal thickness measurement by enhanced depth imaging and swept-source optical coherence tomography in central serous chorioretinopathy. BMC Ophthalmol. 2014; 14: 145.
  9. Zhou M, Wang W, Ding X, Huang W, Chen S, Laties AM, et al. Choroidal thickness in fellow eyes of patients with acute primary angle-closure measured by enhanced depth imaging spectraldomain optical coherence tomography. Invest Ophthalmol Vis Sci. 2013; 54: 1971–8.
  10. Huang W, Wang W, Zhou M, Chen S, Gao X, Fan Q, et al. Peripapillary choroidal thickness in healthy Chinese subjects. BMC Ophthalmol. 2013; 13: 23.
  11. Zhou M, Wang W, Huang W, Gao X, Li Z, Li X, et al. Is increased choroidal thickness association with primary angle closure? ActaOphthalmol. 2014; 92: e514–20.
  12. Hirooka K, Tenkumo K, Fujiwara A, Baba T, Sato S, Shiraga F. Evaluation of peripapillary choroidal thickness in patients with normal-tension glaucoma. BMC Ophthalmol. 2012; 12: 29.
  13. Margolis R, Spaide RF. A pilot study of enhanced depth imaging optical coherence tomography of the choroid in normal eyes. Am J Ophthalmol. 2009; 147(5): 811-815.
  14. Wang S, Wang Y, Gao X, Qian N, Zhou Y. Choroidal thickness and high myopia: a cross-sectional study and meta-analysis. BMC Ophthalmology 2015; 15: 70.
  15. Gupta P, Saw SM, Carol Y. Cheung, Michael J. A. Girard, Jean Martial Mari, Mayuri Bhargava et al. Choroidal thickness and high myopia: a case–control study of young Chinese men in Singapore. Acta Ophthalmologica 2014: 1-8.
  16. Fujiwara T, Imamura Y, Margolis R, Slakter JS &Spaide RF. Enhanced depth imaging optical coherence tomography of the choroid in highly myopic eyes. Am J Ophthalmol 2009; 148: 445– 50.
  17. El-Zawahry WM. Subfoveal choroidal thickness versus foveal thickness in patients Vincent SJ, Collins MJ, Read SA, Carney LG. Retinal and choroidal thickness in myopic anisometropia. Invest Ophthalmol Vis Sci. 2013 Apr; 54(4): 2445-56.
  18. Vincent SJ, Collins MJ, Read SA, Carney LG. Retinal and choroidal thickness in myopic anisometropia. Invest Ophthalmol Vis Sci. 2013 Apr; 54(4): 2445-56.
  19. Sadler TW (2006): Langman,s medical embryology. Baltimore, MD: Lippincott Williams and Wilkins.

Corresponding Author

Dr Nazia Anjum