History Of Laser Eye Surgery – Part One

This is the story of a procedure that has become the single most common operation with over 35 million performed worldwide by 2010. It has evolved into a 10-minute process that can correct 96% of all refractive errors with minimal discomfort, a recovery time of a few hours and dramatic visual results overnight.

It is the confluence of numerous brilliant ideas and bio-engineering accomplishments that have led to what is one of the most miraculous medical procedures in the history of medicine. The procedure is called laser in-situ keratomileusis and is commonly referred to as: LASIK (a type of Laser Eye Surgery). We’ve segmented the history into three posts which will be published this week.

Enjoy and please feel free to contact us should you have any questions on Laser Eye Surgery at London Vision Clinic.

Barraquer Develops Keratomileusis – 1948

The concept that refractive error could be corrected by sculpting corneal stromal tissue to change corneal curvature was the brainchild of Jose Ignacio Barraquer Moner in 1948. (1-3)

Barraquer developed a procedure he coined as keratomileusis (4) (the “K” in LASIK) which involved resecting a disc of anterior corneal tissue which was then frozen in liquid nitrogen, placed on a modified watchmaker’s lathe and milled to change corneal curvature. The word “keratomileusis” literally means “sculpting” of the “cornea”

The resection was achieved using a manually driven microkeratome that he designed specifically for this purpose based on a carpenter’s plane.

Barraquer then used trigonometric calculations to derive the volume of tissue removal required for a particular refractive error correction. In his 1964 thesis on the ‘Law of Thicknesses’ (5) he described that “the cornea flattens when tissue is removed from the centre and steepens when tissue is removed from the periphery.”

His earliest patients were treated in the early 1960s at the Clinica de Marly in Bogota, where he had to leave the patient on the operating table after resecting the corneal disc while he hurried 3km across town to where he had set up the lathing workshop in his home, before returning to suture the thawed and reshaped corneal disc back onto the patient’s eye by a torque anti-torque suture using microsurgical instruments and an operating microscope all of which were inventions of his for this purpose.

Around that time others were experimenting with Barraquer’s ideas. Krwawicz (6-8) in Poland, published a 1964 paper describing a series of three highly myopic eyes in which he had performed a “stromectomy” where he manually made two stromal cuts at different depths with a flat knife and removed the thin lamella of intervening stroma.

And Pureskin in Russia described the concept of an incomplete anterior corneal resection in order to leave a naturally hinged flap.

Several thousand keratomileusis procedures were performed at the Barraquer Instituto de America in the 1970s and early to mid-1980s and surgeons from around the world came to learn this difficult, but miraculous technique.

Two of Barraquer’s disciples worked on a refinement of the technique to perform keratomileusis without freezing referred to as the Barraquer-Krumeich-Swinger (BKS) technique was published in 1986. (9)

Ruiz Performs Keratomileusis On The Eye

This BKS non-freeze technique involved placing the resected disc epithelial side down onto a curved suction die or mould where a second pass of the microkeratome removed tissue from the exposed posterior stromal surface according to the shape of the die. The BKS technique aimed to reduce surgical trauma to the tissues and improve visual recovery time.

At around the same time, another non-freeze technique called in-situ keratomileusis was developed. Ruiz, who having completed his residency at the Barraquer Institute was performing up to twenty keratomileusis procedures in a day, first performed the procedure.

Ruiz was interrupted in his flow by a corneal disc resection which was found to be too thin for the required tissue removal – with the patient on the table he came up with the idea of passing the microkeratome a second time using a different suction ring with the height adjusted to resect the required lenticule directly from the stromal bed. This was called in-situ keratomileusis (the “I” in LASIK)

Ruiz then was responsible for designing a gear system to automate the passage of the microkeratome head. This eased the technical challenges of using a manual microkeratome as the head could be passed with a constant and reproducible speed, therefore avoiding irregular resections and greatly improving the accuracy. (10) The procedure became known as Automated Lamellar Keratoplasty.

Commonly known as ALK, this procedure was further refined by replacing the disc without a suture and adhesion was aided by drying, after which the eye was patched over-night until the epithelium sealed it into place.

In 1989 Ruiz presented a paper demonstrating how stopping the microkeratome before the end of the pass could produce a flap. The flap would then be tucked under the second microkeratome ring applied for the stromal resection thus leaving a hinge to simplify the replacement and reduce cap related complications.

In the second instalment of the series, we take you from the point that the excimer laser was used in keratomileusis to the establishment of PRK criteria which ultimately paved the way for LASIK Laser Eye Surgery.

Sources:

  • 1. Barraquer JI. Queratoplastia refractiva. Est e Inf. Oftal Inst Barraquer. 1949:2-10.
  • 2. Barraquer JI. Method for cutting lamellar grafts in frozen cornea. New orientation for refractive surgery. Arch Soc Am Oftal Optom. 1958:1-271.
  • 3. Barraquer JI. [Autokeratoplasty with optical carving for the correction of myopia (Keratomileusis)]. An Med Espec. 1965;51:66-82.
  • 4. Barraquer JI. Keratomileusis. Int Surg. 1967;48:103-117.
  • 5. Barraquer JI. Conducta de la còmea frente a los cambios de espesor. Arch Soc Am Oftal Optom. 1964:5-81.
  • 6. Krwawicz T. Lamellar Corneal Stromectomy For The Operative Treatment Of Myopia. A Preliminary Report. Am J Ophthalmol. 1964;57:828-833.
  • 7. Krwawicz T. [Further Results Of Partial Lamellar Resection Of The Corneal Stroma For Correction Of High-Grade Myopia. (Stromectomia Corneae Lamellaris)]. Klin Oczna. 1965;35:13-17.
  • 8. Pureskin NP. [Weakening ocular refraction by means of partial stromectomy of cornea under experimental conditions]. Vestn Oftalmol. 1967;80:19-24.
  • 9. Swinger CA, Krumeich JH, Cassiday D. Planar Lamellar Refractive Keratoplasty. J Refract Surg. 1986:17-24.
  • 10. Ruiz L. In Situ Keratomileusis. Invest Ophthalmol Vis Sci. 1988;[Suppl]:392.