Intacs: The intrastromal corneal ring

The quest for improved efficacy and safety continues to be a driving force behind the advances in refractive surgical technology. The ability to resha pe the human cornea without removing or destroying tissue has long been an elusive goal. The idea of changing corneal curvature by expanding rather th an subtracting tissue volume represents a significant departure from the cu rrent tissue-destructive procedures of photorefractive keratectomy (PRK) an d laser-assisted in situ keratomileusis (LASIK). In April 1999, the: U.S. Food and Drug Administration (FDA) granted the fir st-ever approval for an implant to be permanently placed into the human cor nea for the purpose of altering its curvature. The Keravision intrastromal corneal ring (ICR) segments, or "Intacs," are now an exciting addition to t he refractive surgeon's palate of options for correcting low-level nearsigh tedness. Though many may look at this achievement with only modest wonder, it represents an entirely new platform of technology now available to the r efractive surgeon and is a landmark event in the evolution of refractive su rgery.