Flap-induced and laser-induced ocular aberrations in a two-step LASIK procedure

Samra Waheed, Maria Regina Chalita, Meng Xu, Ronald R. Krueger

Research output: Contribution to journalArticle

47 Citations (Scopus)

Abstract

PURPOSE: To identity aberrations created by making a laser in situ keratomileusis (LASIK) flap and treating the refractive error with laser ablation at a later date. METHODS: Twenty-two eyes (11 patients) underwent a two-step LASIK procedure with the Alcon LADAR-Vision laser (Alcon Laboratories, Ft Worth, Tex). In the first step, a flap was created, and 1 month later the flap was lifted and laser ablation performed. Aberrations were measured with the LADARWave wavefront measurement device preoperatively, after making the flap (1 day, 1 week, 1 month) and after laser treatment (1 week and 3 months). Two different microkeratomes were used (Moria M2 [Moria; Antony, France] and SKBM [Alcon]). With the SKBM, all flap hinges were nasal; with the Moria M2, the flap hinge was randomly selected as superior in one eye and nasal in the other. RESULTS: A slight hyperopic shift was seen in the manifest and wavefront refractions at 1 week and 1 month after flap creation for the Moria M2, but not for the SKBM. Statistically significant change in manifest sphere with the Moria M2 showed a mean shift at 1 month of +0.50±0.08 diopters (D) whereas the SKBM showed no mean shift, but less reproducibility, +0.06±0.17 D. Higher order aberrations after flap creation were statistically significantly higher for all except coma with both microkeratomes, but with no predictable trends observed. Although higher in magnitude, post flap aberrations were less than one quarter the increase noted in post laser aberrations, except for "other terms." CONCLUSIONS: Creating a LASIK flap induces changes in lower and higher order ocular aberrations. The change in lower order terms is microkeratome dependent. Higher order aberrations increase to a much larger degree after laser than after flap, making a two-step procedure unnecessary in conventional LASIK.

Original languageEnglish (US)
Pages (from-to)346-352
Number of pages7
JournalJournal of Refractive Surgery
Volume21
Issue number4
StatePublished - Jul 1 2005

Fingerprint

Laser In Situ Keratomileusis
Lasers
Laser Therapy
Nose
Unnecessary Procedures
Refractive Errors
Coma
France
Equipment and Supplies
Therapeutics

ASJC Scopus subject areas

  • Surgery
  • Ophthalmology

Cite this

Flap-induced and laser-induced ocular aberrations in a two-step LASIK procedure. / Waheed, Samra; Chalita, Maria Regina; Xu, Meng; Krueger, Ronald R.

In: Journal of Refractive Surgery, Vol. 21, No. 4, 01.07.2005, p. 346-352.

Research output: Contribution to journalArticle

Waheed, Samra ; Chalita, Maria Regina ; Xu, Meng ; Krueger, Ronald R. / Flap-induced and laser-induced ocular aberrations in a two-step LASIK procedure. In: Journal of Refractive Surgery. 2005 ; Vol. 21, No. 4. pp. 346-352.
@article{cb97719e65c4474ebdea64228aa1fdfb,
title = "Flap-induced and laser-induced ocular aberrations in a two-step LASIK procedure",
abstract = "PURPOSE: To identity aberrations created by making a laser in situ keratomileusis (LASIK) flap and treating the refractive error with laser ablation at a later date. METHODS: Twenty-two eyes (11 patients) underwent a two-step LASIK procedure with the Alcon LADAR-Vision laser (Alcon Laboratories, Ft Worth, Tex). In the first step, a flap was created, and 1 month later the flap was lifted and laser ablation performed. Aberrations were measured with the LADARWave wavefront measurement device preoperatively, after making the flap (1 day, 1 week, 1 month) and after laser treatment (1 week and 3 months). Two different microkeratomes were used (Moria M2 [Moria; Antony, France] and SKBM [Alcon]). With the SKBM, all flap hinges were nasal; with the Moria M2, the flap hinge was randomly selected as superior in one eye and nasal in the other. RESULTS: A slight hyperopic shift was seen in the manifest and wavefront refractions at 1 week and 1 month after flap creation for the Moria M2, but not for the SKBM. Statistically significant change in manifest sphere with the Moria M2 showed a mean shift at 1 month of +0.50±0.08 diopters (D) whereas the SKBM showed no mean shift, but less reproducibility, +0.06±0.17 D. Higher order aberrations after flap creation were statistically significantly higher for all except coma with both microkeratomes, but with no predictable trends observed. Although higher in magnitude, post flap aberrations were less than one quarter the increase noted in post laser aberrations, except for {"}other terms.{"} CONCLUSIONS: Creating a LASIK flap induces changes in lower and higher order ocular aberrations. The change in lower order terms is microkeratome dependent. Higher order aberrations increase to a much larger degree after laser than after flap, making a two-step procedure unnecessary in conventional LASIK.",
author = "Samra Waheed and Chalita, {Maria Regina} and Meng Xu and Krueger, {Ronald R.}",
year = "2005",
month = "7",
day = "1",
language = "English (US)",
volume = "21",
pages = "346--352",
journal = "Journal of Refractive Surgery",
issn = "0883-0444",
publisher = "Slack Incorporated",
number = "4",

}

TY - JOUR

T1 - Flap-induced and laser-induced ocular aberrations in a two-step LASIK procedure

AU - Waheed, Samra

AU - Chalita, Maria Regina

AU - Xu, Meng

AU - Krueger, Ronald R.

PY - 2005/7/1

Y1 - 2005/7/1

N2 - PURPOSE: To identity aberrations created by making a laser in situ keratomileusis (LASIK) flap and treating the refractive error with laser ablation at a later date. METHODS: Twenty-two eyes (11 patients) underwent a two-step LASIK procedure with the Alcon LADAR-Vision laser (Alcon Laboratories, Ft Worth, Tex). In the first step, a flap was created, and 1 month later the flap was lifted and laser ablation performed. Aberrations were measured with the LADARWave wavefront measurement device preoperatively, after making the flap (1 day, 1 week, 1 month) and after laser treatment (1 week and 3 months). Two different microkeratomes were used (Moria M2 [Moria; Antony, France] and SKBM [Alcon]). With the SKBM, all flap hinges were nasal; with the Moria M2, the flap hinge was randomly selected as superior in one eye and nasal in the other. RESULTS: A slight hyperopic shift was seen in the manifest and wavefront refractions at 1 week and 1 month after flap creation for the Moria M2, but not for the SKBM. Statistically significant change in manifest sphere with the Moria M2 showed a mean shift at 1 month of +0.50±0.08 diopters (D) whereas the SKBM showed no mean shift, but less reproducibility, +0.06±0.17 D. Higher order aberrations after flap creation were statistically significantly higher for all except coma with both microkeratomes, but with no predictable trends observed. Although higher in magnitude, post flap aberrations were less than one quarter the increase noted in post laser aberrations, except for "other terms." CONCLUSIONS: Creating a LASIK flap induces changes in lower and higher order ocular aberrations. The change in lower order terms is microkeratome dependent. Higher order aberrations increase to a much larger degree after laser than after flap, making a two-step procedure unnecessary in conventional LASIK.

AB - PURPOSE: To identity aberrations created by making a laser in situ keratomileusis (LASIK) flap and treating the refractive error with laser ablation at a later date. METHODS: Twenty-two eyes (11 patients) underwent a two-step LASIK procedure with the Alcon LADAR-Vision laser (Alcon Laboratories, Ft Worth, Tex). In the first step, a flap was created, and 1 month later the flap was lifted and laser ablation performed. Aberrations were measured with the LADARWave wavefront measurement device preoperatively, after making the flap (1 day, 1 week, 1 month) and after laser treatment (1 week and 3 months). Two different microkeratomes were used (Moria M2 [Moria; Antony, France] and SKBM [Alcon]). With the SKBM, all flap hinges were nasal; with the Moria M2, the flap hinge was randomly selected as superior in one eye and nasal in the other. RESULTS: A slight hyperopic shift was seen in the manifest and wavefront refractions at 1 week and 1 month after flap creation for the Moria M2, but not for the SKBM. Statistically significant change in manifest sphere with the Moria M2 showed a mean shift at 1 month of +0.50±0.08 diopters (D) whereas the SKBM showed no mean shift, but less reproducibility, +0.06±0.17 D. Higher order aberrations after flap creation were statistically significantly higher for all except coma with both microkeratomes, but with no predictable trends observed. Although higher in magnitude, post flap aberrations were less than one quarter the increase noted in post laser aberrations, except for "other terms." CONCLUSIONS: Creating a LASIK flap induces changes in lower and higher order ocular aberrations. The change in lower order terms is microkeratome dependent. Higher order aberrations increase to a much larger degree after laser than after flap, making a two-step procedure unnecessary in conventional LASIK.

UR - http://www.scopus.com/inward/record.url?scp=22644443342&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=22644443342&partnerID=8YFLogxK

M3 - Article

C2 - 16128331

AN - SCOPUS:22644443342

VL - 21

SP - 346

EP - 352

JO - Journal of Refractive Surgery

JF - Journal of Refractive Surgery

SN - 0883-0444

IS - 4

ER -