Topographic screening of donor eyes for previous refractive surgery

Hick, Sandrine; Laliberté, Jean‐François; Meunier, Jean; Ousley, Paula J.; Terry, Mark A.; Brunette, Isabelle

doi:10.1016/j.jcrs.2005.12.035

Cited by 11 publications

(6 citation statements)

References 37 publications

(43 reference statements)

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“…Previous studies have investigated the role of elevation topography to: (i) establish normal patterns and standards 45,46 , (ii) identify high-risk individuals who may experience corneal ectasia after LASIK 18,27 , (iii) screen eye-bank eyes for previous refractive surgery 47 , (iv) evaluate possible changes in posterior corneal elevation after laser in situ keratomileusis (LASIK) or photorefractive keratectomy (PRK) 48 , and (v) build population-based average three dimensional (3-D) atlases or standards of the human cornea 49 . Different patterns have been proposed to describe aspects of elevation topography maps including: “island”, “regular ridge”, “irregular ridge”, “incomplete ridge”, and “unclassified” 50-52 .…”

Section: Discussionmentioning

confidence: 99%

Corneal Elevation Topography: Best Fit Sphere, Elevation Distance, Asphericity, Toricity, and Clinical Implications

Gatinel

Malet

Hoang–Xuan

et al. 2011

Cornea

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Purpose To describe the effect of the corneal asphericity and toricity on the map patterns and Best Fit Sphere (BFS) characteristics in elevation topography. Methods The corneal surface was modeled as a biconic surface of principal radii and asphericity values of (r1, r2) and (Q1, Q2), respectively. The apex of the biconic surface corresponded to the origin of a polar coordinates system. Minimization of the squared residuals was used to calculate the values of the radii of the best fit spheres (BFS) and apex distance (A-values :z distance between the corneal apex and the BFS) of the modelled corneal surface for various configurations relating to commonly clinical measured values of apical radius, asphericity and toricity. Results Increased apical radius of curvature and increased prolateness (negative asphericity) led to an increase in BFS radius, but had opposite effects on the A-value. Increased prolateness resulted in increased BFS radius and A-value. Increasing toricity did not alter these findings. Color-plot elevation maps of the modelled corneal surface showed complete ridge patterns when toricity was increased and showed incomplete ridge and island patterns when prolateness was increased. Conclusions High A-values in patients with corneal astigmatism may result from steep apical curvature and/or high prolateness (negative asphericity). The BFS radius may help in distinguishing between these two causes of increased A-values. Increased prolateness and decreased apical radius of curvature (often seen in keratoconus) have opposite effects on the BFS radius but similar effects on the apex distance.

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Section: Discussionmentioning

confidence: 99%

Corneal Elevation Topography: Best Fit Sphere, Elevation Distance, Asphericity, Toricity, and Clinical Implications

Gatinel

Malet

Hoang–Xuan

et al. 2011

Cornea

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“…Whether eye banks should accept corneas that have had previous PRK with adjuvant mitomycin-C for donation is unknown; some studies have indicated no effect of PRK with mitomycin-C on the endothelium 37-39 whereas other studies have found detrimental effects, including increased endothelial cell loss. 40-42 However, determining which potential donor corneas have had PRK is a challenge for eye banks, 43-45 and determining which corneas also received adjuvant mitomycin-C will be more difficult.…”

Section: Discussionmentioning

confidence: 99%

Corneal Endothelial Cell Loss 9 Years After Excimer Laser Keratorefractive Surgery

Patel

Bourne

2009

Arch Ophthalmol

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“…However, the application of these techniques increases the cost of tissue preparation, and each method has its own sensitivity and specificity. 1,[5][6][7] Additionally, the reliability of the proposed methods could be reduced by postmortem tissue changes. 8 To the best of our knowledge, this is the first case of PK that necessitated rekeratoplasty due to poor postoperative refractive status of the eye.…”

Section: Discussionmentioning

confidence: 99%

Rekeratoplasty for the Correction of Refractive Status Due to Post-LASIK Donor Graft

Yağcı

Palamar²,

Selver³

et al. 2022

Exp Clin Transplant

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We report a case of cataract-combined penetrating keratoplasty that required rekeratoplasty for refractive status because of the inadvertent use of a cornea from a donor who had undergone LASIK surgery. The case presents the use of perioperative visualization, anterior segment optic coherence tomography, and histopathologic confirmation. A 63-year-old female patient with leukoma and cataract in the left eye underwent combined cataract surgery and penetrating keratoplasty. During surgery, a jelly-like layer extending a few millimeters in diameter was observed around the lenticule. In addition, the graft was noticed to separate into 2 distinct layers, which were attributed to previous LASIK surgery. Optic coherence tomography of the postoperative anterior segment of the donor cornea also revealed a LASIK flap layer. Postoperative corneal topography displayed a power distribution of 46.8, 36.9, and 22.1 D at the 1.0-, 3.0-, and 7.0-mm corneal zones, respectively, and the best visual acuity did not improve. For this reason, rekeratoplasty was performed. Histopathologic evaluation of the excised button confirmed the presence of a LASIK flap. To the best of our knowledge, this case is the first report of penetrating keratoplasty that required rekeratoplasty due to refractive status. Perioperative discovery of a jelly-like layer due to a LASIK flap has also not been previously described. As the number of refractive surgeries increases, reliable, low-cost, and simple screening methods must be developed to more successfully detect postrefractive surgery tissue in the donor cornea supply.

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Topographic screening of donor eyes for previous refractive surgery

Abstract: The results led to a proposed criteria-based system using Orbscan corneal topography to screen eye-bank eyes for previous refractive surgery.

Cited by 11 publications

References 37 publications

Corneal Elevation Topography: Best Fit Sphere, Elevation Distance, Asphericity, Toricity, and Clinical Implications

Corneal Elevation Topography: Best Fit Sphere, Elevation Distance, Asphericity, Toricity, and Clinical Implications

Corneal Endothelial Cell Loss 9 Years After Excimer Laser Keratorefractive Surgery

Rekeratoplasty for the Correction of Refractive Status Due to Post-LASIK Donor Graft

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