Evaluation and Comparison of Posterior Corneal Elevation Parameters in Different Grades of Keratoconus By Pentacam
-
Reyhane Shariati Moghaddam
,
Asgar Doostdar
,
Payam Nabovati
,
Abbasali Yekta
,
Mohammad-Mehdi Sadoughi
,
Ali Mirzajani
,
Mehdi Khabazkhoob
Abstract
To evaluate and compare posterior corneal elevation data and anterior segment parameters in different grades of keratoconus by Pentacam. 114 eyes of 114 keratoconic patients (85 men and 56 women) with a mean age of 31.6±4.7 years were evaluated with a Pentacam Scheimpflug camera. Keratoconic eyes were divided into 3 groups or grades according to the maximum keratometry reading: mild or grade I (K=50 or less than 50 diopters [D]), moderate or grade II (K=50.0 to 55.0 D), and severe or grade III (K=55.0 D or higher). The posterior corneal parameters were obtained posterior. There were no statistically significant differences between keratoconus grades in terms of sex (P=0.661). Also, there were no statistically significant differences between 3 grades in terms of age (P=0.214). There were statistically significant differences in anterior keratometry readings (K), anterior chamber depth (ACD), anterior chamber angle (ACA), and all pachymetric corneal measurements between all groups. With the progression of the disease, posterior K readings and all posterior elevation measurements were statistically different between the three grades. However, there were no significant differences in pupil diameter, anterior chamber volume (ACV), and corneal volume (CV) between the three grades of keratoconus. According to the results of this study, height data of posterior elevation, when combined with corneal anterior segment parameter, could provide a useful keratoconus severity classification tool.
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24. Nilsson M, Miller W, Cerviño A, Bergmanson JPG, Brautaset RL. Evaluation of the anterior chamber angle in keratoconus and normal subjects. Cont Lens Anterior Eye 2015;38:277-82.
25. Ambrósio R, Alonso RS, Luz A, Coca Velarde LG. Corneal-thickness spatial profile and corneal-volume distribution: Tomographic indices to detect keratoconus. J Cataract Refract Surg 2006;32:1851-9.
26. Bennet ES, Henry VA. Clinical manual of contact lenses. 4nd ed. Philadelphia: Lippincott Williams & Wilkins; 2013.
27. Meek KM, Tuft SJ, Huang Y, et al. Changes in collagen orientation and distribution in keratoconus corneas. Invest Ophthalmol Vis Sci 2005;46:1948-56.
28. Mollan SP, Wolffsohn JS, Nessim M, Laiquzzaman M, Sivakumar S, Hartley S, et al. Accuracy of Goldmann, ocular response analyser, Pascal and TonoPen XL tonometry in keratoconic and normal eyes. Br J Ophthalmol 2008;92:1661-5.
29. Mannion LS, Tromans C, O’Donnell C. Reduction in corneal volume with severity of keratoconus. Curr Eye Res 2011;36:522-7.
2. Jafarinasab MR, Shirzadeh E, Feizi S, Karimian F, Akaberi A, Hasanpour H. Sensitivity and specificity of posterior and anterior corneal elevation measured by Orbscan in diagnosis of clinical and subclinical keratoconus. J Ophthalmic Vis Res 2015;101:10-5.
3. Schlegel Z, Hoang-Xuan T, Gatinel D. Comparison of and correlation between anterior and posterior corneal elevation maps in normal eyes and keratoconus-suspect eyes. J Cataract Refract Surg 2008;34:789-95.
4. de Sanctis U, Loiacono C, Richiardi L, Turco D, Mutani B, Grignolo FM. Sensitivity and Specificity of Posterior Corneal Elevation Measured by Pentacam in Discriminating Keratoconus/Subclinical Keratoconus. Ophthalmology 2008;115:1534-9.
5. Muftuoglu O, Ayar O, Ozulken K, Ozyol E, Akıncı A. Posterior corneal elevation and back difference corneal elevation in diagnosing forme fruste keratoconus in the fellow eyes of unilateral keratoconus patients. J Cataract Refract Surg 2013;39:1348-57.
6. Hashemi H, Beiranvand A, Khabazkhoob M, Mehravaran S, Emamian MH, Yekta A, et al. Corneal elevation and keratoconus indices in a 40- to 64-year-old population, Shahroud Eye Study. J Curr Ophthalmol 2015;27:92-8.
7. Miháltz K, Kovács I, Takács Á, Nagy ZZ. Evaluation of keratometric, pachymetric, and elevation parameters of keratoconic corneas with pentacam. Cornea 2009;28:976-80.
8. Tomidokoro A, Oshika T, Amano S, Higaki S, Maeda N, Miyata K. Changes in anterior and posterior corneal curvatures in keratoconus. Ophthalmology 2000;107:1328-32.
9. Colin J, Velou S. Current surgical options for keratoconus. J Cataract Refract Surg 2003;29:379-86.
10. Mazzotta C, Balestrazzi A, Traversi C, et al. Treatment of progressive keratoconus by riboflavin-UVA-induced cross-linking of corneal collagen: ultrastructural analysis by Heidelberg Retinal Tomograph II in vivo confocal microscopy in humans. Cornea 2007;26:390-7.
11. Wollensak G. Crosslinking treatment of progressive keratoconus: new hope. Curr Opin Ophthalmol 2006;17:356-60.
12. Hellstedt T, Mäkelä J, Uusitalo R, Emre S, Uusitalo R. Treating keratoconus with Intacs corneal ring segments. J Refract Surg 2005;21:236-46.
13. Colin J. European clinical evaluation: Use of Intacs for the treatment of keratoconus. J Cataract Refract Surg 2006;32:747-55.
14. Alió JL, Shabayek MH, Belda JI, Correas P, Feijoo ED. Analysis of results related to good and bad outcomes of Intacs implantation for keratoconus correction. J Cataract Refract Surg 2006;32:756-61.
15. Leccisotti A, Fields SV. Angle-supported phakic intraocular lenses in eyes with keratoconus and myopia. J Cataract Refract Surg 2003;29:1530-6.
16. Budo C, Bartels MC, van Rij G. Implantation of Artisan toric phakic intraocular lenses for the correction of astigmatism and spherical errors in patients with keratoconus. J Refract Surg 2005;21:218-22.
17. Emre S, Doganay S, Yologlu S. Evaluation of anterior segment parameters in keratoconic eyes measured with the Pentacam system. J Cataract Refract Surg 2007;33:1708-12.
18. Ishii R, Kamiya K, Igarashi A, Shimizu K, Utsumi Y, Kumanomido T. Correlation of Corneal Elevation With Severity of Keratoconus by Means of Anterior and Posterior Topographic Analysis. Cornea 2012;31:253-8.
19. Piñero DP, Alió JL, Alesón A, Vergara ME, Miranda M. Corneal volume, pachymetry, and correlation of anterior and posterior corneal shape in subclinical and different stages of clinical keratoconus. J Cataract Refract Surg 2010;36:814-25.
20. Edmonds CR, Wung S-F, Pemberton B, Surrett S. Comparison of Anterior Chamber Depth of Normal and Keratoconus Eyes Using Scheimpflug Photography. Eye Contact Lens 2009;35:120-2.
21. Kovács I, Miháltz K, Németh J, Nagy ZZ. Anterior chamber characteristics of keratoconus assessed by rotating Scheimpflug imaging. J Cataract Refract Surg 2010;36:1101-6.
22. Fontes BM, Ambrósio R, Jardim D, Velarde GC, Nosé W. Corneal Biomechanical Metrics and Anterior Segment Parameters in Mild Keratoconus. Ophthalmology 2010;117:673-9.
23. Smolek MK, Klyce SD. Is keratoconus a true ectasia? An evaluation of corneal surface area. Arch Ophthalmol 2000;118:1179-86.
24. Nilsson M, Miller W, Cerviño A, Bergmanson JPG, Brautaset RL. Evaluation of the anterior chamber angle in keratoconus and normal subjects. Cont Lens Anterior Eye 2015;38:277-82.
25. Ambrósio R, Alonso RS, Luz A, Coca Velarde LG. Corneal-thickness spatial profile and corneal-volume distribution: Tomographic indices to detect keratoconus. J Cataract Refract Surg 2006;32:1851-9.
26. Bennet ES, Henry VA. Clinical manual of contact lenses. 4nd ed. Philadelphia: Lippincott Williams & Wilkins; 2013.
27. Meek KM, Tuft SJ, Huang Y, et al. Changes in collagen orientation and distribution in keratoconus corneas. Invest Ophthalmol Vis Sci 2005;46:1948-56.
28. Mollan SP, Wolffsohn JS, Nessim M, Laiquzzaman M, Sivakumar S, Hartley S, et al. Accuracy of Goldmann, ocular response analyser, Pascal and TonoPen XL tonometry in keratoconic and normal eyes. Br J Ophthalmol 2008;92:1661-5.
29. Mannion LS, Tromans C, O’Donnell C. Reduction in corneal volume with severity of keratoconus. Curr Eye Res 2011;36:522-7.
| Files | ||
| Issue | Vol 60, No 3 (2022) | |
| Section | Original Article(s) | |
| DOI | https://doi.org/10.18502/acta.v60i3.9004 | |
| Keywords | ||
| Keratoconus Severity Posterior corneal elevation Pentacam Anterior segment parameters | ||
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This work is licensed under a Creative Commons Attribution-NonCommercial 4.0 International License. |
How to Cite
1.
Shariati Moghaddam R, Doostdar A, Nabovati P, Yekta A, Sadoughi M-M, Mirzajani A, Khabazkhoob M. Evaluation and Comparison of Posterior Corneal Elevation Parameters in Different Grades of Keratoconus By Pentacam. Acta Med Iran. 2022;60(3):165-170.
