High-speed optical coherence tomography for management after laser in situ keratomileusis

Purpose: To report applications of optical coherence tomography (OCT) in the management of laser in situ keratomileusis (LASIK) related problems. Setting: Doheny Eye Institute and Department of Ophthalmology, Keck School of Medicine of the University of Southern California, Los Angeles, California, USA. Methods: Five patients referred for LASIK-related problems were enrolled in a prospective observational study. Clinical examination, ultrasound (US) pachymetry, Placido ring slit-scanning corneal topography (Orbscan II, Bausch & Lomb), and high-speed corneal OCT were performed. Results: In cases of regression and keratectasia, OCT provided thickness measurements of the cornea, flap, and posterior stromal bed. Locations of tissue loss and flap interface planes were identified in a case with a recut enhancement complication. The information was used to determine whether further laser ablation was safe, confirm keratectasia, and manage complications. Optical coherence tomography measurements of central corneal thickness agreed well with US pachymetry measurements (difference 6.4 μm ± 11.7 [SD]) (P = .026), while Orbscan significantly underestimated corneal thickness (-67.5 ± 72.5 μm) (P = .17). Conclusions: High-speed OCT provided noncontact imaging and measurement of LASIK anatomy. It was useful in monitoring LASIK results and evaluating complications.