|LETTER TO THE EDITOR
|Year : 2015 | Volume
| Issue : 1 | Page : 78
Emrullah Beyazyildiz1, Özlem Beyazyildiz2, Hasan Basri Arifoglu3, Aysegül Kocak Altintas2, Şükrü Gültekin Köklü2
1 Department of Ophthalmology, Gazi Mustafa Kemal Government Hospital, Ankara, Turkey
2 Department of Ophthalmology, Ulucanlar Eye Research and Training Hospital, Ankara, Turkey
3 Department of Ophthalmology, Kaçkar Government Hospital, Rize, Turkey
|Date of Web Publication||16-Feb-2015|
Gazi Mustafa Kemal Devlet Hastenesi, Silahtar Caddesi No: 2, Gazi Mahallesi, Yenimahalle, Ankara
Source of Support: None, Conflict of Interest: None
|How to cite this article:|
Beyazyildiz E, Beyazyildiz Ö, Arifoglu HB, Altintas AK, Köklü &G. Author's reply. Indian J Ophthalmol 2015;63:78
|How to cite this URL:|
Beyazyildiz E, Beyazyildiz Ö, Arifoglu HB, Altintas AK, Köklü &G. Author's reply. Indian J Ophthalmol [serial online] 2015 [cited 2019 Oct 22];63:78. Available from: http://www.ijo.in/text.asp?2015/63/1/78/151492
We thank the authors for their interest to our article.  In our study we have demonstrated that exfoliative glaucoma (EXG) patients have lower corneal hysteresis (CH) levels and at this point we have hypothesized that this lower CH levels may be a reason for rapid progression in visual deterioration in EXG patients.
The authors asked for correlations between visual field test (mean deviation [MD]) and corneal biomechanical properties. We did not correlate visual field parameters with corneal biochemical properties in our study. As we have stated, our study is cross-sectional observational study. We thought that simply comparison of MD value of the visual field with corneal biomechanical properties may not be relevant. Because visual field test is a dynamic test and may be affected by several factors.  MD could be affected by refraction errors, small pupils and hazy media. ,, We know that patients with EXG have smaller pupil diameter and a higher incidence of lenticular opasification.  In order to find and observe a correlation between visual field parameters and corneal biochemical parameters, researchers should start a prospective study and should actively observe changes in visual field parameters in patients with lower CH and show correlation between CH and visual field deterioration. As we have stated in our study, there is a need for longitudinal prospective studies to show changes in visual field defects relative to baseline levels in patients with different corneal biomechanical properties to prove that lower CH is associated with a more rapid progression of optic neuropathy in eyes with EXG.
Authors asked for whether any adjustment performed for multiple comparisons. There are many factors affecting CH, apart from our study findings, such as axial length, age, corneal curvature, corneal disease, etc. , In our study, age was significantly different between groups. As we have stated in the discussion section of the manuscript, this factor may be a limitation for our study. But comparison of parameters adjusting only for age, intraocular pressure or any ocular response analyzer measure would not be enough because CH is affected by many ocular and systemic factors. We did not made any adjustments for multiple comparison of corneal biomechanical properties in statistical analysis of this study.
We appreciate the opportunity given to us by the editor and authors and we hope these replies will help the understanding of corneal biomechanical properties in EXG eyes or other types of glaucoma and encourage researchers for longitudinal prospective studies with larger study groups.
| References|| |
Beyazyildiz E, Beyazyildiz O, Arifoglu HB, Altintas AK, Köklü SG. Comparison of ocular response analyzer parameters in primary open angle glaucoma and exfoliative glaucoma patients. Indian J Ophthalmol 2014;62:782-7.
Prata TS, De Moraes CG, Teng CC, Tello C, Ritch R, Liebmann JM. Factors affecting rates of visual field progression in glaucoma patients with optic disc hemorrhage. Ophthalmology 2010;117:24-9.
Herse PR. Factors influencing normal perimetric thresholds obtained using the Humphrey Field Analyzer. Invest Ophthalmol Vis Sci 1992;33:611-7.
Koller G, Haas A, Zulauf M, Koerner F, Mojon D. Influence of refractive correction on peripheral visual field in static perimetry. Graefes Arch Clin Exp Ophthalmol 2001;239:759-62.
Congdon NG, Quigley HA, Hung PT, Wang TH, Ho TC, Glovinsky Y. Impact of age, various forms of cataract, and visual acuity on whole-field scotopic sensitivity screening for glaucoma in rural Taiwan. Arch Ophthalmol 1995;113:1138-43.
Drolsum L, Ringvold A, Nicolaissen B. Cataract and glaucoma surgery in pseudoexfoliation syndrome: A review. Acta Ophthalmol Scand 2007;85:810-21.
Sullivan-Mee M, Katiyar S, Pensyl D, Halverson KD, Qualls C. Relative importance of factors affecting corneal hysteresis measurement. Optom Vis Sci 2012;89:E803-11.
Goldich Y, Barkana Y, Pras E, Fish A, Mandel Y, Hirsh A, et al.
Variations in corneal biomechanical parameters and central corneal thickness during the menstrual cycle. J Cataract Refract Surg 2011;37:1507-11.