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Anales de la Sociedad Mexicana de Oftalmología y Archivos de la Asociación Para Evitar la Ceguera en México

2009, Number 2

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Rev Mex Oftalmol 2009; 83 (2)

Comparación del índice de esfericidad pre y postquirúrgico en pacientes con astigmatismo miópico compuesto con tratamiento tissue saving contra asférico

Sánchez-Solórzano A, Muñoz-Ibarra P

Language: Spanish
References: 12
Page: 91-94
PDF size: 90.73 Kb.


ABSTRACT

Objective: to compare the presurgical and postsurgical Q value in eyes submitted to aspheric treatment versus tissue saving treatment in patients with compound myopic astigmatism.
Methods: Twenty eyes were enrolled in the study, ten left eyes with compound myopic astigmatism received tissue saving treatment, average ablation of 70 µm, optic zone treatment of 6.5-7.0 mm and aberrations average of high order RSM less than 0.4 U. Ten right eyes were submitted to aspheric treatment. The presurgical spherical equivalent was 3.25 D in both eyes.
Results: We measured the Q value after one week, one month and three months taking as a reference the value obtained at three months.
The average Q value in both eyes before surgery was -0.25, at three months after surgery with aspheric treatment Q value was -0.50 and with tissue saving +0.18. In both eyes the spherical equivalent after surgery was -0.15D.
Conclusions: Aspherical treatment maintains corneal prolacity meanwhile tissue saving treatment increases the corneal oblacity after surgery. The objective of aspherical treatment is the less induction of spherical aberration.


REFERENCES

  1. Artal P, Berrio E, Guirao A y cols. Contribution of the cornea and internal surfaces to the change of ocular aberrations with age. J Opt Soc Am A. 2002; 19:137-143.

  2. Anera RG, Jiménez JR, Jiménez del Barco L y cols. Changes in corneal asphericity alter laser in situ keratomileusis. J Cataract Refract Surg. 2003; 29:762-768.

  3. Seiler T, Kaemmerer M, Mierdel P, Krinke HE. Ocular optical aberrations after photorefractive keratectomy for myopia and myopic astigmatism. Arch Ophthalmol 2000; 118:17-21.

  4. Probst LE, Machat JJ. Mathematics of laser in situ keratomileusis for high myopia. J Cataract Refract Surg 1998; 24:190-195.

  5. Seiler T, Quurke AW. Iatrogenic keratectasia after LASIK in a case of forme fruste keratoconus. J Cataract Refract Surg 1998; 24:1007-1009.

  6. McLeod SD, Kisla TA, Caro NC. Iatrogenic keratoconus: corneal ectasia following laser in situ keratomileusis for myopia. Arch Ophthalmol 2000; 118:282-284.

  7. Seiler T., Genth U, Holschbach A, Derse M. Aspheric photorefractive keratectomy with excimer laser. Refract Corneal Surg 1999; 9:166-172.

  8. MacRae S, Schwiegerling J, Snyder RW. Corneal ablation patterns to correct for spherical aberration corneal ablation design. J Refract Surg. 1999; 15:246-248.

  9. Gatinel D, Malet J, Hoang-Xuan T. Analysis of customized corneal ablations: Theoretical limitations of increasing negative asphericity. Invest Ophthalmol Visl Sci 2002; 43:941-948.

  10. Holladay JT, Dudeja DR, Chang J. Functional vision and corneal changes alter laser in situ keratomileusis determined by contrast sensitivity, glare testing, and corneal topography. J Cataratct Refract Surg 1999; 25:663-669.

  11. Hong X, Thibos LN. Longitudinal evaluation of optical aberrations following laser in situ keratomileusis surgery. J Refract Surg 2000; 16(supl):S647-S650.

  12. Hersh PS, Shath SI, Holladay JT. Corneal asphericity following excimer laser photorefractive keratectomy. Summit PRK Topography Study Group. Opthalmic Surg Lasers 1996; 27:421-428.




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