Clinical results of topography-based customized ablations in highly aberrated eyes and keratoconus/ectasia with cross-linking

J Refract Surg. 2012 Nov;28(11 Suppl):S841-8. doi: 10.3928/1081597X-20121005-06.


Purpose: To report results of a series of highly aberrated corneas treated with a topography-guided excimer laser ablation.

Methods: Retrospective, nonrandomized, consecutive series of eyes treated with topography-guided photorefractive keratectomy (TG-PRK) with the customized topographical neutralization technique (TNT). Cases included postoperative refractive surgery decentered ablations, optical zone enlargement, asymmetrical astigmatism, postoperative radial keratotomy (RK), postoperative keratoplasty, keratoconus combined with collagen cross-linking (CXL), and postoperative LASIK ectasia combined with CXL. Uncorrected distance visual acuity (UDVA), corrected distance visual acuity (CDVA), and manifest refraction were analyzed preoperatively and 6 months postoperatively.

Results: In decentered ablation cases, 94% of 37 eyes were within 1.00 diopter (D) of the attempted refractive outcome, with 76% within 0.50 D. Mean topographic, central, optical zone of uniform (monodioptric) power increased from 3.5 to 5.2 mm in 25 eyes. Thirty-one eyes treated for asymmetrical astigmatism showed improvement in cylinder from mean 1.31 to 0.52 D. Ten of 11 eyes treated for previous RK astigmatism achieved postoperative UDVA 20/40 or better. Twenty-seven eyes with postoperative keratoplasty astigmatism were treated, with 7 (25.9%) eyes gaining > or = 2 lines and 12 (44.4%) eyes gaining > or = 1 line of CDVA. Of eyes with keratoconus that were treated using TG-PRK with CXL, 42 (58%) eyes had UDVA 20/40 or better, and 66 (92%) eyes had CDVA 20/40 or better. Twelve (71%) of 17 eyes treated for postoperative LASIK ectasia using TG-PRK with CXL had UDVA 20/40 or better. Nine (53%) eyes gained > or = 2 lines of CDVA.

Conclusions: Topography-guided laser treatment with custom TNT, combined with CXL in keratoconus and ectasia, is an effective, safe, and increasingly predictable option for highly aberrated corneas.

MeSH terms

  • Adult
  • Collagen / metabolism
  • Combined Modality Therapy
  • Corneal Stroma / metabolism
  • Corneal Topography*
  • Cross-Linking Reagents / therapeutic use*
  • Dilatation, Pathologic / drug therapy
  • Dilatation, Pathologic / surgery
  • Female
  • Humans
  • Keratoconus / drug therapy*
  • Keratoconus / surgery*
  • Keratomileusis, Laser In Situ*
  • Lasers, Excimer / therapeutic use*
  • Male
  • Middle Aged
  • Patient Satisfaction
  • Photorefractive Keratectomy*
  • Photosensitizing Agents / therapeutic use
  • Postoperative Complications
  • Retrospective Studies
  • Riboflavin / therapeutic use
  • Ultraviolet Rays
  • Visual Acuity / physiology


  • Cross-Linking Reagents
  • Photosensitizing Agents
  • Collagen
  • Riboflavin