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Two Centuries of Progress
ESCRS Heritage Lecture surveys 200 years of refractive surgery. Dermot McGrath reports from the 39th Congress of the ESCRS in Amsterdam
The history of refractive surgery over the past two centuries is a stop-start tale of innovation, inspiration, and the occasional sprinkling of good fortune, said Patrick I Condon MD in the annual ESCRS Heritage Lecture.
In a broad survey of 200 years of innovation and progress in refractive surgery, Dr Condon took his audience on a journey beginning with the first surgical correction of astigmatism in the late nineteenth century through to the modern era of LASIK and femtosecond laser surgery.
Going back to the roots of refractive surgery, Dr Condon said the oldest refractive procedure we know of is the surgical correction of astigmatism with two individual accounts in the mid1800s in which a large amount of astigmatism was corrected by a single Graefe knife incision.
Toward the end of that century, the Dutch ophthalmologist Leendert Jan Lans described his meticulous experimental animal studies that produced the basic principles for astigmatism correction.
“This is the basis of the corneal coupling effect and the basic principle for the treatment of astigmatism that we still use to this day,” Dr Condon said.
Dr Condon related how myopia reversal was initially discovered by Saito in Japan in 1936 when he found that flattening the cornea with keratotomies in a young man with a severe corneal injury led to a reduction in his myopia.
A further refinement came in 1974 when Fyodorov in Russia developed incisional keratotomy for removing corneal foreign bodies, which involved 16 radial corneal incisions using a metal blade.
The technique’s popularity was to prove short-lived, however.
George Waring MD was the chief investigator in a prospective evaluation of radial keratotomy (RK) in the United States that ran from 1982 to 1993, which showed a hyperopic shift of one dioptre or more. This proved catastrophic for patients approaching presbyopia and resulted in RK abandonment.
José Ignacio Barraquer’s introduction of the microkeratome in 1964 began the era of corneal lamellar refractive surgery. The microkeratome was used to remove a corneal disc at a depth of 300 microns, which was then frozen and transferred to a cryolathe which removed 110 microns from the posterior surface and involved the refractive element of the surgery.
A further enhancement came with Jörg Krumeich’s nonfreeze technique using the guided trephine system to remove the corneal flap, followed by combined research by Barraquer, Krumeich, and Casimir Swinger to perform the refractive cut using the same system.
“This enabled us to perform the entire operation in a non-freeze technique using just one microkeratome,” Dr Condon said.
He also highlighted technological developments in the 1970s that ultimately led to the introduction of excimer laser technology into ophthalmology in the late 1980s—such as Lucio Buratto combining the microkeratome and the excimer laser to reshape the cornea. Around the same time, Greek surgeon Ioannis Pallikaris elaborated the concept of the nasal corneal hinge and in situ ablation. This made for easier cap repositioning, thus began the era of laser-assisted in situ keratomileusis (LASIK).
In recent years, the femtosecond laser has increasingly supplanted the excimer laser in ophthalmology for refractive purposes, Dr Condon said, who noted how the technology is being used not only for refractive surgery but also therapeutically for keratoconus and corneal transplant surgery.
Dr Condon rounded off his lecture with a round-up of the major advances in IOL technology over recent decades, including angle-supported anterior chamber IOLs and posterior chamber IOLs. Angle-supported anterior chamber IOLs fell out of favour due to issues with long-term endothelial cell loss and other complications, while encountered problems of subluxation, pupil block, glaucoma, and lens opacities, among others.
“I think the biggest problem of all was the sizing of posterior IOLs within the eye to prevent them [from] moving. For this, the white-to-white measurements we used for anterior chamber lenses [were] not accurate enough and [were] replaced by sulcusto-sulcus measurements with ultrasound and laser scanning ophthalmoscopy,” Dr Condon said.
Iris-fixated anterior chamber IOLs represented an “incredible advance” in lens technology, Dr Condon said, beginning with Jan Worst’s lobster-claw lens in 1979 through to designs of the Artisan IOL (Ophtec) for hyperopia and astigmatism and the Verisyse and foldable Artiflex lens in 2003.
“The beauty of these lenses was there was very little endothelial cell loss with them, with one study showing there was a loss of between 0.7% and 8.8% over a 10-year period, which is a pretty good record,” he concluded.
Patrick Condon MCh, FRCS, FRCOphth, lives in Waterford, Ireland. During his long career, Dr Condon acquired Fellowships from the Royal Colleges of Surgeons of Ireland, England, and Scotland and a Mastership in Surgery (National University of Ireland). He is currently a life fellow of the Royal Society of Medicine (London), an emeritus member of the International Intraocular Implant Club, and an active member of the Royal Academy of Medicine in Ireland and the Irish College of Ophthalmologists.