Tracker-assisted Laser In Situ Keratomileusis for Myopia Using the Autonomous Scanning and Tracking Laser 12-Month Results Deepak K. Chitkara, FRCOphth, Emanuel Rosen, MD, Christa Gore, MSc, Frank Howes, FRCOphth, Elizabeth Kowalewski, BSc Objective: To determine the safety, efficacy, and predictability of the Autonomous scanning and tracking laser for the correction of myopia and myopic astigmatism with laser in situ keratomileusis (LASIK) procedure. Design: Retrospective, noncomparative case series. Participants: The first 129 consecutive eyes with up to 13.00 diopters (D) of myopia and 5.00 D of astigmatism. Intervention: Myopic tracker-assisted LASIK (T-LASIK) using the Autonomous Laser (Alcon Summit Auton- omous, Waltham, MA) and Hansatome microkeratome (Bausch & Lomb Surgical, Bracknell, England). Main Outcome Measures: Uncorrected visual acuity (UCVA), manifest spherical equivalent (MSE), best spectacle-corrected visual acuity (BSCVA), and complications were studied. Results: At 12 months, the mean MSE was 0.02  1.01 D, with 79.1% of eyes within 0.5 D and 89.9% of eyes within 1 D of the intended correction. UCVA was 20/20 or better in 71.4%, 20/25 or better in 78.5%, and 20/40 or better in 92.8% of eyes. Two eyes (1.6%) lost 2 lines and five eyes (3.8%) gained 2 lines of BSCVA. Sixteen eyes (12.4%) required retreatment to correct residual myopia or astigmatism. After retreatment, 14 of 16 eyes were within 0.5 D of emmetropia. Nine eyes (6.9%) had minor flap complications; two eyes (1.6%) had grade 2 diffuse lamellar keratitis, of which one eye had associated peripheral flap melt. One eye showed slight decentration; this eye was rolling throughout the procedure. All eyes had some dryness, with 10% severe enough to require temporary punctual occlusion with plugs. Conclusions: T-LASIK for myopic astigmatism with the Autonomous Laser is relatively safe, effective, and predictable. The tracker seems to be effective, and the complications are relatively few. Retreatment rates are acceptable and can be performed safely and effectively to improve visual outcome. The outcomes are compa- rable with other published data. Ophthalmology 2002;109:965–972 © 2002 by the American Academy of Ophthalmology. Over the last 5 years, laser in situ keratomileusis (LASIK) has emerged as the procedure of choice for the surgical correction of low to moderate myopia. The main advantage of LASIK over photorefractive keratectomy (PRK) is the shortened wound-healing response because of the preserva- tion of corneal epithelium and Bowman’s layer. Attempts to improve visual outcomes have focused on achieving a smooth ablation profile to further reduce stromal cellular response. 1–3 Small beam lasers potentially could provide smoother ablation profiles but require a tracking mechanism to stabi- lize the treatment zone during the longer ablation period. However, the longer ablation times may result in excessive corneal drying and a more unpredictable result. The Auton- omous laser has been shown to be effective in treatment of myopia by PRK during clinical trials for Food and Drug Administration approval 4 Our Autonomous Laser (Alcon Summit Autonomous, Waltham, MA) system was the first commercially available system that was designed for per- forming LASIK over a wide range of refractive errors from 6.00 diopters (D) of hyperopia to 10 D myopia and up to 6.00 D of astigmatism. The laser has an active tracker Originally received: October 22, 2000. Accepted: September 20, 2001. Manuscript no. 200528. From the Rosen Eye Surgery Centre, Manchester, England. Presented in part at the ESCRS, Brussels, September 2000, and at the annual meeting of the American Academy of Ophthalmology, Dallas, Texas, October 2000. The authors have no proprietary interest in any of the materials presented in this article. Reprint requests to Deepak K. Chitkara, FRCOphth, Rosen Eye Surgery Centre, The Alexandra Hospital—Victoria Park, 108-112 Daisy Bank Road, Manchester M14 5QH, England. 965 © 2002 by the American Academy of Ophthalmology ISSN 0161-6420/02/$–see front matter Published by Elsevier Science Inc. PII S0161-6420(02)01013-8