Penetrating keratoplasty using femtosecond laser-enabled keratoplasty with zig-zag incisions versus a mechanical trephine in patients with keratoconus

Cornea Eye Institute, Cedars Sinai, 50 N. La Cienega Blvd., Suite 340, Beverly Hills, CA 90211, USA
The British journal of ophthalmology (Impact Factor: 2.98). 07/2012; 96(9):1195-9. DOI: 10.1136/bjophthalmol-2012-301662
Source: PubMed

ABSTRACT This paper will compare the visual outcomes of two different penetrating keratoplasty (PKP) techniques in patients with keratoconus. It is a retrospective comparative surgical case series of 116 keratoconus patients (137 eyes) who had PKP at the Cornea Eye Institute, Beverly Hills, California, USA.
56 keratoconus patients (66 eyes) underwent femtosecond laser-enabled keratoplasty (FLEK) with a zig-zag incision configuration. Their visual parameters were compared with those of 60 patients (71 eyes) who had traditional blade mechanical trephination PKP. The range of follow-up was between 3 and 6 months. The main outcome measures included uncorrected visual acuity and best spectacle-corrected visual acuity (BSCVA), manifest refractive spherical equivalent and topographically determined astigmatism.
BSCVA was significantly better as early as 3 months postoperatively (p=0.001) in the FLEK group. Visual recovery to 20/40 after 3 months was significantly better in the FLEK group (p<0.001). Topographic astigmatism was lower in the FLEK group, but the difference between the two groups reached significance only at 3 months of follow-up (p=0.001). Postoperative complications noted were not different between the two groups.
Faster visual recovery and better long-term outcomes were observed in keratoconus patients who had FLEK compared with those who had the mechanical PKP procedure with 6 months of postoperative follow-up.

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    • "The difference in the donor graft size may also contribute to faster visual recovery in the FLAK group. Although we did not usually remove the 10-0 nylon sutures during the 6-month follow-up period in the current study, FLAK enables us to remove the sutures in the early postoperative period, which may be another advantage over conventional PK [13], [16], [17]. "
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    ABSTRACT: Purpose To assess the clinical outcomes of femtosecond laser-assisted keratoplasty (FLAK) using the VisuMax femtosecond laser system, and to compare them with those of conventional penetrating keratoplasty (PK). Methods We retrospectively examined 20 eyes of 20 consecutive patients undergoing FLAK and 20 eyes of 20 age- and diagnosis-matched patients undergoing conventional PK. We quantitatively assessed corneal astigmatism, refractive astigmatism, and corrected visual acuity, 1, 3, and 6 months postoperatively, and endothelial cell density 6 months postoperatively. Results Corneal and refractive astigmatism after FLAK were significantly lower after FLAK than that after conventional PK at 3 and 6 months postoperatively (p = 0.04 and p = 0.03, respectively, Mann-Whitney U test). FLAK provided significantly faster visual recovery than conventional PK at 1 month postoperatively (p = 0.02), but not at 3 and 6 months postoperatively (p = 0.52 and p = 0.80, respectively). We found no significant differences in the change in endothelial cell density between the two groups (p = 0.30). Conclusions FLAK using the VisuMax femtosecond laser system induces significantly less corneal and refractive astigmatism than conventional PK, and provides significantly faster visual recovery in the early postoperative period, possibly because the geometry of the donor-recipient matching is more physiological and requires less tight sutures. It is suggested that FLAK has advantages over conventional PK, in terms of astigmatism and fast visual recovery.
    PLoS ONE 08/2014; 9(8):e105464. DOI:10.1371/journal.pone.0105464 · 3.23 Impact Factor
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    ABSTRACT: The purpose of this study was to provide an update of significant cornea literature published in the past 1 year. This was a literature review. The authors conducted a 1-year English-language literature search on PubMed, from January 1, 2012, to December 31, 2012, using the following terms: corneal transplantation, anterior lamellar keratoplasty, penetrating keratoplasty, endothelial keratoplasty, Descemet stripping automated endothelial keratoplasty, Descemet membrane endothelial keratoplasty, Descemet membrane endothelial transfer, ocular surface epithelial transplantation, limbal epithelial transplantation, cultivated oral mucosal epithelial transplantation, keratoprosthesis, infectious keratitis, cross-linking, keratoconus, corneal neovascularization, corneal imaging, optical coherence tomography, Pentacam Scheimpflug imaging, and in vivo confocal microscopy. This review includes original articles and review articles that contain significant updates and novel aspects in the field of cornea from the following journals: American Journal of Ophthalmology, British Journal of Ophthalmology, Ophthalmology, Investigative Ophthalmology and Visual Science, and Cornea. Letters to the editor, unpublished work, manuscripts not in English, and abstracts were not included. This review highlights significant literature that is applicable to the practicing ophthalmologist.
    11/2013; 2(6):401-413. DOI:10.1097/APO.0000000000000022
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    ABSTRACT: The aim of this study was to compare the outcomes of "mushroom" femtosecond laser-enabled keratoplasty (M-FLEK) with those of conventional penetrating keratoplasty (PKP) in eyes with keratoconus. The femtosecond laser-enabled "mushroom" pattern keratoplasty technique results in less postoperative astigmatism and higher endothelial cell counts compared with conventional PKP in patients with keratoconus. This was a nonrandomized retrospective, single private center clinical study. Between March 2010 and April 2012, 26 eyes underwent M-FLEK and 33 eyes underwent conventional PKP. Data on preoperative and postoperative manifest refraction, uncorrected visual acuity and best-corrected visual acuity (BCVA), endothelial cell counts, vector analysis, and complications were retrieved and analyzed. At 12 months of follow-up, the mean logMAR BCVA was 0.31 ± 0.55 in the M-FLEK group and 0.32 ± 0.21 in the PKP group (P = 0.91). The mean spherical equivalent was similar between the groups. The mean manifest cylinder was significantly lower in the M-FLEK group (-2.84 ± 1.08 diopters) than in the PKP group (-3.93 ± 2.26 diopters; P = 0.03). There was a smaller mean endothelial cell loss in the M-FLEK group compared with the PKP group (32.1% vs 38.7%, respectively, P = 0.17) 1 year postoperatively. The complication rates were similar for both groups. M-FLEK appears to be a safe procedure that results in less astigmatism and a trend toward higher endothelial cell counts compared with conventional PKP, with similar postoperative BCVA.
    Cornea 03/2014; 33(5). DOI:10.1097/ICO.0000000000000080 · 2.04 Impact Factor
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