Retratamento em cirurgias refrativas com excimer laser

Vázquez, Mercedes; Schor, Paulo; Chamon, Wallace; Allemann, Norma; Campos, Mauro

doi:10.5935/0004-2749.19980104

RESUMO

Propósito:

Avaliar a segurança e eficácia do retratamento da miopia e astigmatismo com excimer laser.

Métodos:

Foram estudados onze olhos de dez pacientes, com idade variando de 20 a 46 anos. A técnica de reoperação foi a ceratectomia fotorrefrativa (PRK) em seis olhos (54,54%), a ceratectomia foto-terapêutica epitelial (PTK-e) seguida de PRK em dois olhos (18,18%), e a ceratectomia fotoastigmática (PARK) em dois olhos (18,18%). O retratamento foi realizado de 5 a 16 meses após o primeiro tratamento (média de 9,3 ± 3,4 meses). O seguimento pós-operatório variou de 6 a 23 meses (média de 9,2 ± 5,4 meses). Foi utilizado o excimer laser Apex plus Summit, e avaliada a refração, a acuidade visual e a opacidade sub-epitelial, ou "haze".

Resultados:

O equivalente esférico (EE) médio inicial foi de -8,50 ± 3,66D. Após o primeiro tratamento houve uma diminuição de 55% no EE médio inicial para -4,04 ± 2,42D, que foi estatisticamente significante (p = 0,0004). Após o retratamento houve uma diminuição de 28% no EE médio em relação ao primeiro tratamento, não sendo estatisticamente significante (p=0,09). O astigmatismo médio pre-operatório foi de -2,41 ± -1,84. Após o primeiro tratamento (média de -2,30 ± 1,70) e retratamento (média de -2,10 ± 0,8) não houve mudança estatisticamente significante (p=0,19 e p=0,30 respectivamente). Após o retratamento, 36,36% dos olhos apresentaram AV sc ≥ 20/40 e 63,63% AV sc ≥ 20/60. Trinta e seis por cento dos olhos apresentaram uma refração entre ± 1D da emetropia e 54,54% entre ± 2D da emetropia. Em relação ao pré-operatório, 45,55% perderam entre 1 e 5 linhas da melhor acuidade visual corrigida por óculos após o retratamento.

Conclusão:

O retratamento com excimer laser é pouco eficaz no caso de altas ametropias residuais, podendo induzir a opacidade sub-epitelial e perda de linhas de visão.

Palavras-chaves:
Ceratectomia fotorrefrativa; Córnea; Cirurgia; Miopia; Reoperações; Complicações

SUMMARY

Purpose:

To evaluate the safety and efficacy of repeated excimer laser for treatment of residual myopia and astigmatism.

Methods:

Eleven eyes (ten patients) with age ranging from 20 to 46 years underwent reablation with excimer laser. Six eyes (54.54%) were treated using photorefractive keratectomy (PRK), two (18.18%) epithelial phototherapeutic keratectomy (PTK-e) followed by PRK, and two (18.18%) with photoastigmatic keratectomy (PARK). Retreatment was done 5 to 16 month after the first treatment (average 9.3 ± 3.4 months) and follow-up ranged from 6 to 23 months (average 9.2 ± 5.4 months). The laser used was the Apex plus Summit excimer laser. Refractive changes, visual acuity and corneal haze were evaluated.

Results:

Mean preoperative spherical equivalent was -8.50 ± 3.66D. After the first treatment there was a reduction in the mean spherical equivalent of 55%, -4.04 ± 2.42D, statistically significant (p = 0.0004). After retreatment there was a reduction in the mean spherical equivalent of 28%o compared to the first treatment but this reduction was not statistically significant (p = 0.09). Pre-operative astigmatism was -2.41 ± 1.84. After the first (-2.30 ± 1.70) and second treatment (-2.10 ± 0.80) there was no significant reduction (p = 0.19 e p = 0.30 respectively). After retreatment 36.36% of the eyes presented an uncorrected visual acuity ≥ 20/40 and 63.63% ≥ 20/60. Thirty three percent were within ±1 diopter of emmetropia and 54.54% within 2 diopters. Five eyes (45.54%) lost between one to five lines of the best spectacle-corrected visual acuity after retreatment when compared to preoperative.

Conclusion:

Excimer laser retreatment lacks efectivity in cases of high refractive residual ametropies. Decrease in the best corrected visual acuity may be expected as a side effect in these cases.

Key words:
Photorefractive keratectomy; Myopia; Cornea; Surgery; Re-intervention; Complication

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REFERÊNCIAS BIBLIOGRÁFICAS

¹
Salz J. Corneal Laser Surgery. St Louis L: Mosby - Year Book; 1995.
²
Snibson G, Carson C, Aldred G, Taylor H. One-year evaluation of excimer laser photorefractive keratectomy for myopia and myopic astigmatism. Arch Ophthalmol 1995; 113:994-1000.
³
Dutt S, Steinert R, Raizman M, Puliafito C. One year result of excimer laser photorefractive keratectomy for low to moderate myopia. Arch Ophthalmol 1994; 112:1427-36.
⁴
Krueger R, Talamo J, McDonald M, Vamell R, Wagoner M, Me Donnel P. Clinical analysis of excimer laser photorefractive keratectomy using a multiple zone technique for severe myopia. Am J Ophthalmol 1995;119:263-74.
⁵
Seiler T, Derse M, Pham T. Repeated excimer laser treatment after photorefractive keratectomy. Arch Ophthalmol 1992;110:1230-3.
⁶
Corbett M, O'Brart D, Warburton F, Marshall J. Biologic and environmental risk factors for regression after photorefractive keratectomy. Ophthalmology 1996;103:1381-91.
⁷
Kim JH, Hahn TW, Young CL. Photorefractive keratectomy in 202 myopic eyes: on year results. Refract. Corneal Surg. 9(suppl):s11-s16, 1993.
⁸
Epstein D, Tengroth B, Fagerholm P, Hamberg-Nystrom H. Excimer retreatments ofregression after photorefractive keratectomy. Am J Ophthalmol 1994;117:456-61.
⁹
Sher N, Hardten D, Fudingsland B, Demarchi J, Carpel M, Doughman D, Lane S, Ostrow C, Eiferman R, Frantz J, Robin J, Telfair W, Lindstrom R. 193-nm excimer photorefractive keratectomy in high myopia. Ophthalmology 1994;101: 1575-82.
¹⁰
Snibson G, McCarty C, Alfred G, Levin S, Taylor H Retreatment after excimer laser photorefractive keratectomy. Am J Ophthalmol 1996; 121:250-7.
¹¹
Spadea L, Bianco G, Balestrazzi E. Four techniques for retreatment after excimer laser photorefractive keratectomy. J Refract Surg 1996;12:693-6.
¹²
Lawless M, Cohen P, Rogers C. Retreatment ofundercorrected photorefractive keratectomy for myopia. J Refract Corneal Surg 1994;10(suppl):174-7.
¹³
Pop M, Aras M. Photorefractive Keratectomy retreatments for regression. Ophthalmology 1996; 103: 1979-84.
¹⁴
Sutton G, Kalski R, Lawless M, Rogers C. Excimer retreatment for scarring and regression after photorefractive keratectomy for myopia. Br J Ophthalmol 1995;79:756-9.

Datas de Publicação

Publicação nesta coleção
Feb 1998

Este é um artigo publicado em acesso aberto (Open Access) sob a licença Creative Commons Attribution, que permite uso, distribuição e reprodução em qualquer meio, sem restrições desde que o trabalho original seja corretamente citado.

[1] ¹
Salz J. Corneal Laser Surgery. St Louis L: Mosby - Year Book; 1995.

[2] ²
Snibson G, Carson C, Aldred G, Taylor H. One-year evaluation of excimer laser photorefractive keratectomy for myopia and myopic astigmatism. Arch Ophthalmol 1995; 113:994-1000.

[3] ³
Dutt S, Steinert R, Raizman M, Puliafito C. One year result of excimer laser photorefractive keratectomy for low to moderate myopia. Arch Ophthalmol 1994; 112:1427-36.

[4] ⁴
Krueger R, Talamo J, McDonald M, Vamell R, Wagoner M, Me Donnel P. Clinical analysis of excimer laser photorefractive keratectomy using a multiple zone technique for severe myopia. Am J Ophthalmol 1995;119:263-74.

[5] ⁵
Seiler T, Derse M, Pham T. Repeated excimer laser treatment after photorefractive keratectomy. Arch Ophthalmol 1992;110:1230-3.

[6] ⁶
Corbett M, O'Brart D, Warburton F, Marshall J. Biologic and environmental risk factors for regression after photorefractive keratectomy. Ophthalmology 1996;103:1381-91.

[7] ⁷
Kim JH, Hahn TW, Young CL. Photorefractive keratectomy in 202 myopic eyes: on year results. Refract. Corneal Surg. 9(suppl):s11-s16, 1993.

[8] ⁸
Epstein D, Tengroth B, Fagerholm P, Hamberg-Nystrom H. Excimer retreatments ofregression after photorefractive keratectomy. Am J Ophthalmol 1994;117:456-61.

[9] ⁹
Sher N, Hardten D, Fudingsland B, Demarchi J, Carpel M, Doughman D, Lane S, Ostrow C, Eiferman R, Frantz J, Robin J, Telfair W, Lindstrom R. 193-nm excimer photorefractive keratectomy in high myopia. Ophthalmology 1994;101: 1575-82.

[10] ¹⁰
Snibson G, McCarty C, Alfred G, Levin S, Taylor H Retreatment after excimer laser photorefractive keratectomy. Am J Ophthalmol 1996; 121:250-7.

[11] ¹¹
Spadea L, Bianco G, Balestrazzi E. Four techniques for retreatment after excimer laser photorefractive keratectomy. J Refract Surg 1996;12:693-6.

[12] ¹²
Lawless M, Cohen P, Rogers C. Retreatment ofundercorrected photorefractive keratectomy for myopia. J Refract Corneal Surg 1994;10(suppl):174-7.

[13] ¹³
Pop M, Aras M. Photorefractive Keratectomy retreatments for regression. Ophthalmology 1996; 103: 1979-84.

[14] ¹⁴
Sutton G, Kalski R, Lawless M, Rogers C. Excimer retreatment for scarring and regression after photorefractive keratectomy for myopia. Br J Ophthalmol 1995;79:756-9.

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