Recurrence Characteristics on Optical Coherence Tomography and Treatments of Reis-Bücklers Corneal Dystrophy After Phototherapeutic Keratectomy or Penetrating Keratoplasty

Abstract

PurposeTo evaluate the recurrence characteristics on optical coherence tomography and clinical outcomes after phototherapeutic keratectomy (PTK) or penetrating keratoplasty (PKP) in patients with Reis-Bücklers corneal dystrophy (RBCD). DesignRetrospective interventional case series. MethodsSeventeen patients with RBCD (31 eyes, including six surgery-naïve eyes and 25 surgical eyes) received 44 surgical interventions from 1996 through 2022. PTK or PKP was performed as the initial surgical procedure. Significant recurrence was determined when best spectacle-corrected visual acuity decreased at least two lines with increased opacity in the superficial cornea. Repeated PTK or PTK on the corneal graft (CG-PTK) was considered if patients could not endure poor vision due to significant recurrence. Recurrence depth and annual increase in thickness of the central cornea and subepithelial deposits were assessed by anterior segment optical coherence tomography. ResultsThe mean follow-up time was 12.8±8.5 years (range, 2.0–25.5 years). The mean logMAR best spectacle-corrected visual acuity improved from 1.24±0.48 preoperatively to 0.27±0.09 postoperatively in the initial PTK group (13 eyes, P<0.001), from 1.84±0.69 to 0.40±0.13 in the PKP group (12 eyes, P<0.001), from 1.04±0.46 to 0.30±0.07 in the repeated PTK group (12 times in 7 eyes, P<0.001), and from 1.29±0.43 to 0.39±0.11 in the CG-PTK group (7 times in 5 eyes, P=0.001). The median significant recurrence time was 27 months (95% confidence interval 23.9-30.1), 96 months (84.1-107.9), 31 months (28.8-33.1), and 24 months (19.8-28.2), respectively (P<0.001). The depth of superficial deposits located between the epithelium and the anterior stroma was approximately 115μm (85-159μm). The annual thickening of subepithelial deposits was 14±2μm after initial PTK, 7±3μm after PKP, 14±3μm after repeated PTK, and 30±11μm after CG-PTK, compared to 4±2μm in surgery-naïve eyes (P=0.002, 0.515, 0.002, <0.001). The thickness of the central cornea increased by 15±2μm, 7±2μm, 15±3μm, and 31±10μm per year in the four surgery groups, respectively, compared to 5±2μm in surgery-naïve eyes (P=0.001, 0.469, 0.001, <0.001). ConclusionsBetter visual acuity can be achieved after PTK than PKP for treatment of RBCD. The annual thickening of subepithelial deposits may approximate an increase in central corneal thickness. The superficial distribution of subepithelial deposits makes it feasible to perform repeated PTK, even on the corneal allograft, for recurrent RBCD.