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Laser-Assisted In Situ Keratomileusis for Correction of Secondary Hyperopia After Radial Keratotomy

Estimates from the Prospective Evaluation of Radial Keratotomy (PERK) study suggest that approximately 1.2 million patients underwent treatment with incisional radial keratotomy (RK) in the United States between 1980 and 1990. Though many patients initially achieved satisfactory outcomes, an increasing number appear to drift into the hyperopic range years later. Indeed, the 10-year data from the PERK study confirm that as many as 25 to 30% of these patients are now hyperopic, with an additional 1 to 2% being added to these numbers each year. As one can surmise, this represents a considerable number of patients, leading one noted refractive surgeon to describe the situation as “the second great epidemic of anterior segment surgery,” rivaling the “outbreak” of bullous keratopathy seen a few years after the early anterior chamber lens designs were in use (Lindstrom, personal communication, 1998). These patients can pose a unique and difficult challenge to the refractive surgeon. Treatment options have focused on steepening the central cornea with placement of various peripheral circumferential compression sutures. Several techniques have been described, the most popular being the “lasso” suture described by Lindstrom and by Grene (Fig 1). However, enthusiasm for these techniques has been tempered by several factors. The technique is meticulous and challenging, and refractive results are often unpredictable and difficult to titrate. In addition, the steepening effect may be lost over time, and such problems as suture erosion and stromal melting can occur (Fig 2). Additionally, pharmacological manipulation of accommodation with