History Of Laser Eye Surgery – Part ThreeIn this, the third installment in the History of Laser Eye Surgery series, we take you from the first large area ablation in a human eye to remove a corneal scar which was performed by Seiler through to the arrival of LASIK in 1990 as a method of correcting refractive errors.
The Introduction Of PRK – 1988
In 1985, Seiler performed the first large area ablation in a human eye to remove a corneal scar. With the increasing interest in the possibility of performing refractive correction with an excimer laser, the first international workshop on laser corneal surgery was held in Berlin in 1986.
This led to PRK being performed in humans. In early 1988, McDonald performed the first PRK on a sighted eye due for enucleation, while at around the same time L’Esperance and Seiler began also performing PRK, but in blind eyes.
Central ablation of the cornea was performed using different methods:
- L’Esperance suggested small scanning spot excimer lasers, which could be controlled to ablate in specific patterns.
- Marshall proposed using a broad beam laser and a moving iris diaphragm to shape the area to be ablated. For a myopic correction, initially the aperture was sequentially reduced in diameter to create steps on the corneal surface. The number of steps was gradually increased to improve the smoothness of the curved surface.
- Hanna used a rotating-slit laser delivery system; the shape of the slit was determined mathematically to obtain a parabolic ablation profile that resulted from the slit rotation.27
Larger clinical trials followed with commercially available lasers given the encouraging results from the first cases.
In 1991, McDonald reported that myopic PRK treatment with the VISX 20/20 system was safe. In the same year, Lindstrom (36,37,38) demonstrated the safety and efficacy of the Taunton Technologies model LV 2000 excimer laser for myopic PRK and at that time, Gartry (40, 41) and Seiler (42) published outcomes using the Summit Technology Eximed UV200 excimer laser.
Also in 1991, Dausch and Schroeder (39) presented results in high myopes with the Aesculap-Meditec excimer laser and later, in 1993, presented the first hyperopic ablation profiles.
It is at this point that the excimer laser story joins the keratomileusis story to become laser in situ keratomileusis or LASIK.
The Arrival Of LASIK – 1990
The idea of using an excimer laser to ablate tissue under a flap was springing up independently in various parts of the world.
In 1988 Razhev and co-workers in Novosibirsk began using a 5-mm trephine to produce a central 100 microns deep circular keratotomy and then a scalpel to create a lamellar hinged flap. They then used an excimer laser to ablate the stromal bed before replacing the lamellar flap in 4 myopic and 5 hyperopic eyes and presented their results with up to 2 years’ follow-up in September 1990 at Columbia University.
At around the same time Burrato (45) was performing classical keratomileusis, but from October 1989 he used the excimer laser for ablation on the underside of the cap and published his first 30 high myopic eyes with few complications and 1 year follow-up in 1992. In December 1989, Buratto had a case where the cap was too thin for the required tissue removal, much like Ruiz previously with ALK. He decided instead to perform the excimer laser ablation directly on the stromal bed.
Pallikaris also independently conceived of a hinged flap using a microkeratome he had specifically designed for rabbit studies and performed the ablation with an excimer laser on the exposed bed followed by replacement of the flap without sutures, and first used the term LASIK in his 1990 paper. (11, 46)
Pallikaris treated his first patients in October 1990 and published his results on 10 high myopic human eyes with one year-follow-up in 1994. It is this technique, which gave birth to what is now the most commonly performed surgical procedure in the world and realised the dreams of Jose Ignacio Barraquer Moner 40 years in the making.
- 36. Lindstrom RL, Sher NA, Chen V, Bowers RA, Frantz JM, Brown DC, Eiferman R, Lane SS, Parker P, Ostrov C, et al. Use of the 193-NM excimer laser for myopic photorefractive keratectomy in sighted eyes: a multicenter study. Trans Am Ophthalmol Soc. 1991;89:155-172; discussion 172-182.
- 37. Sher NA, Chen V, Bowers RA, Frantz JM, Brown DC, Eiferman R, Lane SS, Parker P, Ostrov C, Doughman D, et al. The use of the 193-nm excimer laser for myopic photorefractive keratectomy in sighted eyes. A multicenter study. Arch Ophthalmol. 1991;109:1525-1530.
- 38. Sher NA, Barak M, Daya S, DeMarchi J, Tucci A, Hardten DR, Frantz JM, Eiferman RA, Parker P, Telfair WB, 3rd, et al. Excimer laser photorefractive keratectomy in high myopia. A multicenter study. Arch Ophthalmol. 1992;110:935-943.
- 39. Dausch D, Klein R, Schroder E. [Photoablative, refractive keratectomy in treatment of myopia. A case study of 134 myopic eyes with 6-months follow-up]. Fortschr Ophthalmol. 1991;88:770-776.
- 40. Gartry DS, Kerr Muir MG, Marshall J. Photorefractive keratectomy with an argon fluoride excimer laser: a clinical study. Refract Corneal Surg. 1991;7:420-435.
- 41. Gartry DS, Kerr Muir MG, Marshall J. Excimer laser photorefractive keratectomy. 18-month follow-up. Ophthalmology. 1992;99:1209-1219.
- 42. Seiler T, Wollensak J. Myopic photorefractive keratectomy with the excimer laser. One-year follow-up. Ophthalmology. 1991;98:1156-1163.
- 43. McDonald MB, Liu JC, Byrd TJ, Abdelmegeed M, Andrade HA, Klyce SD, Varnell R, Munnerlyn CR, Clapham TN, Kaufman HE. Central photorefractive keratectomy for myopia. Partially sighted and normally sighted eyes. Ophthalmology. 1991;98:1327-1337.
- 44. Lindstrom RL, Sher NA, Barak M, DeMarchi J, Tucci A, Daya S, Hardten DR, Frantz JM, Eifermn RA, Parker P, et al. Excimer laser photorefractive keratectomy in high myopia: a multicenter study. Trans Am Ophthalmol Soc. 1992;90:277-296; discussion 296-301.
- 45. Buratto L, Ferrari M, Rama P. Excimer laser intrastromal keratomileusis. Am J Ophthalmol. 1992;113:291-295.
- 46. Pallikaris IG, Papatzanaki ME, Siganos DS, Tsilimbaris MK. A corneal flap technique for laser in situ keratomileusis. Human studies. Arch Ophthalmol. 1991;109:1699-1702.