This study describes a case of nodular epithelial hyperplasia and stromal alterations in a patient with keratoconus who was submitted to topography-guided photorefractive keratectomy (PRK) followed by corneal collagen cross-linking. Debridement of the epithelial nodule was performed. After a 2-year followup, a new topography-guided PRK was indicated. 1. Introduction Keratoconus is a progressive and bilateral noninflammatory corneal disorder characterized by localized protrusion of the cornea with stromal thinning [1, 2]. Corneal topography suggesting keratoconus is associated with greater risk of ectasia after refractive surgery [3], although some authors report good results in surface refractive surgery for eyes with keratoconus or suspected keratoconus [1, 4]. Treatment using corneal collagen cross-linking (CXL) with riboflavin and ultraviolet-A (UVA) light aims to stabilize the progression of keratoconus and other corneal ectasia by inducing cross-links between the stromal collagen molecules, thus promoting greater corneal stromal biomechanical stability [5]. Combined with CXL, refractive surgery becomes a feasible option for selected cases of keratoconus [1]. We report a case in which a patient with keratoconus who was submitted to the photorefractive keratectomy (PRK) technique followed by CXL subsequently presented a central nodular epithelial hyperplasia. This has not been previously described in the research literature. 2. Case Report A 40-year-old Caucasian man with keratoconus was evaluated for refractive surgery in March 2010. Visual acuity (VA) in the right eye (RE) with correction was 20/25 (+1.25, ？2.25, 105°) and in the left eye (LE) was 20/30 (+0.50, ？3.00, 85°). The topography showed keratoconus with maximum apical keratometry of 46.9？D in the RE and 48.9？D in the LE (Figure 1). The thinnest point on the pachymetry map (Orbscan II) was 472？μm in the RE (Figure 2) and 487？μm in the LE. Figure 1: Preoperative corneal topography: (a) RE, (b) LE. Figure 2: RE preoperative pachymetry map generated by Orbscan II, with thinnest corneal point of 472？ μm. Considering that very few studies have investigated the results of combining PRK with CXL, we decided to initially perform the procedure on the nondominant eye only (RE). Topical anesthesia was performed for PRK with 2 drops of proximetacaine hydrochloride 0.5% (Anestalcon, Alcon, S？o Paulo, Brazil) 15 minutes before surgery, with a 5-minute interval between drops, and 1 drop of tetracaine hydrochloride 1% and phenylephrine hydrochloride 0.1% (Anestésico, Allergan, S？o Paulo, Brazil) moments
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