Deepening of incisions after radial keratotomy using the "tickle" technique

Since the introduction of radial keratotomy, accurate incision depth has been difficult to achieve with any corneal knife. To assure repeatable depth of incisions and to adjust the refractive effect of these incisions after the surgery, I have developed a series of techniques that are described in this article and that I refer to as "tickles" in discussion with the patients. Seventeen eyes, from a consecutive series of 102 operations (reoperation rate of 17%), underwent complete opening and/or deepening of undercorrected eight-incision radial keratotomy. This was performed in the immediate postoperative period (3.0 +/- 4.2 months), at the slit-lamp microscope, without peripheral deepening or extension of the optical zone. After the initial radial keratotomy, the average spherical equivalent refraction was -2.04 +/- 0.68 D; after opening and/or deepening the incisions, the average spherical equivalent refraction was -0.53 +/- 0.24 D. The average effect of this procedure was a reduction in myopia of 1.51 D. All 17 eyes had a final refraction between -0.25 and -1.00.