Exodeviation following monocular myopic regression after laser in situ keratomileusis Rengin Yildirim, MD, Yesim Oral, MD, Arzu Uzun, MD We report a 44-year-old woman with intermittent left exotropia of 35 prism diopt- ers at distance who initially exhibited alignment of both eyes after bilateral laser in situ keratomileusis (LASIK). The exophoria was not preserved due to myopic re- gression in the dominant eye. An uneventful LASIK treatment was performed to correct -11.00 -0.50  130 in the right eye and -13.50 -1.50  145 in the left eye. The aim was to achieve emmetropia in both eyes. Although an examination revealed exophoria at near and distance during the 6 months following refractive surgery, the tropic aspect of the divergent deviation appeared in the right eye fol- lowing the myopic regression. Laser in situ keratomileusis is an effective option to achieve binocular visual quality in myopic anisometropic patients. However, myo- pic regression after LASIK may disrupt the binocular visual quality. J Cataract Refract Surg 2003; 29:1031–1033 © 2003 ASCRS and ESCRS L aser in situ keratomileusis (LASIK) and excimer la- ser photorefractive keratectomy (PRK) are widely used for the correction of myopia. 1–4 Binocular prob- lems after PRK and LASIK have been reported. 5–8 There are also studies that demonstrate improvements in binocular visual function after successful refractive surgery. We report a patient with intermittent left exo- tropia who initially exhibited successful alignment and improvement in stereoacuity after achieving em- metropia in both eyes following LASIK. However, the alignment was not preserved due to myopic regression in the right eye. Case Report A 44-year-old white woman had uneventful LASIK at our clinic for the treatment of high myopia and anisometro- pia. The refractive error was -11.00 -0.50  130 in the right eye and -13.50 -1.50  145 in the left eye. Preoper- atively, the best spectacle-corrected visual acuity (BSCVA) was 20/40 and 20/32, respectively. An orthoptic examination showed free motility in all di- rections. Cover testing elicited an intermittent exotropia of 35 prism diopters (PD) at distance in the left eye that could be corrected with spectacles. She exhibited good near stereo acu- ity, which was tested with the TNO random-dot test, but also left suppression in the Worth 4-dot test at distance (6 m) preoperatively (Table 1). A fundoscopic examination showed a regular macula and myopic degeneration of the peripheral retina in both eyes. The central corneal thicknesses were 604 m and 605 m. Laser in situ keratomileusis was performed using the Hansatome ® microkeratome (Bausch & Lomb) and the SVS Apex Plus ® excimer laser (Summit Technology, Inc.). The 160 m base plate was used to cut a corneal flap 160 m thick. Using the SVS Apex Plus excimer laser with 120 mJ/cm 2 fluence and a 10 Hz repetition rate, a spherical ablation of -11.00 D was performed by the LASIK soft- ware in the right eye. An ablation of -13.00 D -1.50  145 was performed using toric PRK with pretreatment software by MO 1 disc in the left eye during the same surgical session. On the first postoperative day, both corneas were clear and successful alignment was achieved with refractions of +1.25 in the right eye and +1.00 +0.75  70 in the left eye. A week after the LASIK procedure, examination showed exo- phoria at near and distance with +0.75 in the right eye and +0.50 +0.50  70 in the left eye. The uncorrected visual acuity (UCVA) was 20/50 in both eyes. Accepted for publication May 8, 2002. From the Department of Ophthalmology, Cerrahpasa Medical School, University of Istanbul (Yildirim and Uzun), and the Ophthalmology Department, Lutfi Kirdar Kartal Research Hospital (Oral), Istanbul, Turkey. None of the authors has a financial or proprietary interest in any product mentioned. Reprint requests to Rengin Yildirim, Adakent Sitesi ND Blok Da: 9, Levent 80670, Istanbul, Turkey. E-mail: reny@turk.net. © 2003 ASCRS and ESCRS 0886-3350/03/$–see front matter Published by Elsevier Inc. doi:10.1016/S0886-3350(02)01695-4