title: Topographic hot spot before descemet stripping automated endothelial keratoplasty is associated with postoperative hyperopic shift.
abstract: OBJECTIVE
  The aim of this study was to investigate topographic "hot spots" on the anterior corneal surface before Descemet stripping automated endothelial keratoplasty (DSAEK) and their effects on postoperative visual acuity and hyperopic shift.
  
  
  METHODS
  Twenty-seven eyes of 27 patients with bullous keratopathy, who underwent DSAEK were studied. We defined a hot spot as a focal area with relatively high refractive power on the anterior corneal surface in eyes with bullous keratopathy. Refractive spherical equivalent, keratometric value, and corneal topography were retrospectively evaluated using anterior segment optical coherence tomography (AS-OCT).
  
  
  RESULTS
  Hot spots were identified in 11 eyes (42.3%) before DSAEK and disappeared in 9 eyes of these eyes (81.8%) at 6 months after DSAEK. AS-OCT revealed focal epithelial thickening in the same areas as the hot spots. There was no significant difference in the postoperative visual acuity between eyes with and without hot spots (P > 0.05). The keratometric value of the anterior corneal surface significantly flattened from 45.7 ± 2.7 diopters (D) before DSAEK to 44.2 ± 2.7 D 1 month after DSAEK in eyes with hot spots (P = 0.01), whereas in eyes without hot spots, there were no significant differences in the keratometric values before and after DSAEK. At 6 months, the refractive change was +1.1 ± 1.3 D in eyes with hot spots and -0.2 ± 0.6 D in eyes without hot spots (P = 0.034).
  
  
  CONCLUSIONS
  In eyes with focal epithelial thickening, topographic hot spots on the anterior corneal surface were observed using AS-OCT. The hot spots disappeared after DSAEK and had no influence on the postoperative visual acuity.
authors.affiliation: *Department of Ophthalmology, Keio University School of Medicine, Tokyo, Japan; and †Department of Ophthalmology, Ichikawa General Hospital, Tokyo Dental College, Chiba, Japan.
authors.forename: Tsutomu
authors.initials: T
authors.lastname: Shimizu
authors.forename: Takefumi
authors.initials: T
authors.lastname: Yamaguchi
authors.forename: Yoshiyuki
authors.initials: Y
authors.lastname: Satake
authors.forename: Jun
authors.initials: J
authors.lastname: Shimazaki
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D000869:Anterior Eye Segment / Q000473:pathology; D003316:Corneal Diseases / Q000473:pathology / Q000601:surgery*; D019781:Corneal Topography; D003886:Descemet Membrane / Q000601:surgery; D057111:Descemet Stripping Endothelial Keratoplasty; D004728:Endothelium, Corneal / Q000637:transplantation*; D005260:Female; D006801:Humans; D006956:Hyperopia / Q000209:etiology*; D008297:Male; D008875:Middle Aged; D011183:Postoperative Complications / Q000209:etiology*; D012189:Retrospective Studies; D041623:Tomography, Optical Coherence / Q000379:methods; D014792:Visual Acuity