Comparison of Visual Results Between Laser-Assisted Subepithelial Keratectomy and Epipolis Laser In Situ Keratomileusis to Correct Myopia and Myopic Astigmatism

doi:10.1016/j.ajo.2008.05.022

American Journal of Ophthalmology

Volume 146, Issue 3, September 2008, Pages 357-362.e2

https://doi.org/10.1016/j.ajo.2008.05.022 Get rights and content

Purpose

To compare the visual results after laser-assisted subepithelial keratectomy (LASEK) and epipolis laser in situ keratomileusis (epi-LASIK) to correct myopia.

Design

Retrospective, interventional, nonrandomized comparative study.

Methods

Patients treated with LASEK to correct myopia ≤−9.00 diopters (D) were compared to age- and refraction-matched patients treated with epi-LASIK using the same excimer laser (Esiris; Schwind Eye Tech Solutions, Kleinostheim, Germany). The epithelial flap was replaced after the ablation in every case. The visual results after both procedures were compared at each postoperative visit (one day, one week, one and three months).

Results

Ninety-four consecutive eyes were included in the study (47 in each group), matched for age and refraction. The preoperative spherical manifest refraction was −3.98 ± 2.40 D in the LASEK group and −3.95 ± 2.40 D in the epi-LASIK group (P = .9) (range −0.50 to −9.00 D). The uncorrected visual acuity (UCVA) one day postoperatively was 0.7 ± 0.2 and 0.5 ± 0.2 (P < .001), and one week after surgery it was 0.8 ± 0.2 and 0.7 ± 0.2, respectively (P = .1). The difference was again statistically significant one month after surgery (0.94 ± 0.1 after LASEK, 0.82 ± 0.1 after epi-LASIK, P < .001), but not three months postoperatively (1.06 ± 0.21 and 1.03 ± 0.18, respectively, P = .1). UCVA was ≥1.0 in 78.7% of LASEK eyes and 65.9% of epi-LASIK eyes three months after surgery. At that moment, the safety indices were 0.99 ± 0.1 after LASEK and 0.93 ± 0.1 after epi-LASIK (P = .04). The efficacy indices were 0.97 ± 0.1 and 0.89 ± 0.1, respectively (P = .01).

Conclusions

Our results suggest a faster visual rehabilitation and better safety and efficacy outcomes after LASEK compared to epi-LASIK with repositioning of the epithelial flap when correcting low to moderate myopia.

Section snippets

Patients and Methods

We performed a retrospective study of consecutive patients (94 eyes) who underwent laser surface ablation, 47 eyes with epi-LASIK and 47 eyes with LASEK, to correct myopia of −9.00 diopters (D) or less of spherical refractive error and cylinder of −3.75 D or less. We included all patients who underwent epi-LASIK in our hospital and fulfilled the inclusion criteria during the period from January 1 to March 31, 2007. We also identified consecutive patients who underwent LASEK during the same

Results

Ninety-four consecutive eyes were included in the study: 47 eyes in the epi-LASIK group and 47 eyes in the LASEK group. The eyes were matched for age and preoperative refraction.

The mean patient age was 31.6 ± 3.5 years in the epi-LASIK group and 31.4 ± 6.1 years in the LASEK group (P = .7). The mean preoperative spherical refraction values were −3.95 ± 2.4 D in the epi-LASIK group (range, −0.50 to −9.00 D) and −3.98 ± 2.4 D in the LASEK group (range, −0.50 to −9.00 D) (P = .9). The mean

Discussion

In the current study, LASEK-treated eyes had better UCVA during the first postoperative month compared to epi-LASIK-treated eyes, differences that were significant one day and one month after surgery. It is noteworthy that the difference one day after surgery was not only significant but also clinically relevant (two lines of UCVA on the Snellen chart).

The mean UCVA did not differ significantly three months postoperatively, but the percentages of eyes with an UCVA equal to or better than 0.5

Miguel A. Teus, MD, PhD, is a summa cum laude graduate of Valladolid University School of Medicine, Spain. He did his Ophthalmology residency at the Ramón y Cajal University Hospital, Madrid, Spain. Dr Teus obtained his PhD in glaucoma with cum laude at the Universidad de Alcalá, Madrid. Dr Teus is a full Professor at the University of Alcalá, Madrid, Head of the Ophthalmology Department of the University Hospital of Alcalá, Madrid, and Medical Director of Vissum Madrid.

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Cited by (24)

Long term results of Epi-LASIK and LASEK for myopia
2014, Contact Lens and Anterior Eye
Citation Excerpt :
In this study we showed that the results of Epi-LASIK and LASEK were similar in terms of UCVA, safety and efficacy indexes at last visits. Teus et al. compared the visual results of LASEK and Epi-LASIK after 3 months from surgery [21]. They suggested that LASEK provides a faster visual rehabilitation and better safety and efficacy indexes after LASEK.
To evaluate the long term clinical and confocal results of mechanical (Epi-LASIK) versus alcohol-assisted laser epithelial keratomileusis (LASEK) for correction of myopia.
Gazi University Medical School, Department of Ophthalmology, Ankara, Turkey.
Retrospective study.
Twenty-two eyes treated with LASEK and twenty eyes treated with Epi-LASIK were evaluated with a mean follow-up duration of 45 months. Mechanical separation of the epithelium was performed with Lasitome epithelial separator, and alcohol-assisted separation with 25 s application of 18% alcohol. Laser ablation was performed with the ESIRIS laser. All patients were examined daily until epithelial closure; at 1, 3, 6, and 12 months; and every year subsequently. Main outcome measures were uncorrected visual acuity (UCVA), manifest refraction, haze, and gray scale value in confocal microscopy, efficacy and safety indexes.
Preoperative myopic spherical equivalent refraction was −4.65 ± 1.74 D in the LASEK and −3.87 ± 1.30 D in the Epi-LASIK-treated eyes (p = 0.36). Of both LASEK and Epi-LASIK-treated eyes, 95% achieved 20/25 or better final UCVA. The grade of haze and mean gray scale value in confocal microscopy were similar in LASEK and Epi-LASIK-treated eyes at all postoperative periods. The efficacy index was 0.94 in LASEK group and 0.96 in Epi-LASIK group (p = 0.44). The safety index was 1.01 in LASEK group and 1.02 in Epi-LASIK group (p = 0.42).
Both LASEK and Epi-LASIK offer safe and effective correction of myopia in the long term.
Epi-LASIK versus LASEK and PRK
2012, Journal of Cataract and Refractive Surgery
Infectious keratitis in 18651 laser surface ablation procedures
2011, Journal of Cataract and Refractive Surgery
To evaluate the incidence, culture results, risk factors, treatment strategies, and visual outcomes of infectious keratitis after surface ablation.
Multicenter study in Spain.
Case series.
The medical records of patients who had surface ablation between January 2003 and December 2009 were reviewed to identify cases of infectious keratitis. The incidence, risk factors, clinical course, days to diagnosis, medical and surgical treatment, and visual outcome were recorded. Main outcome measures were incidence of infectious keratitis after surface ablation, culture results, response to treatment, and visual outcomes.
The study reviewed the records of 9794 patients (18 651 eyes). Infectious keratitis after surface ablation was diagnosed in 39 eyes of 38 patients. The onset of infection was early (within 7 days after surgery) in 28 cases (71.79%). Cultures were positive in 13 of 27 cases in which samples were taken. The most frequently isolated microorganism was Staphylococcus species (9 cases). The final corrected distance visual acuity (CDVA) was 20/20 or better in 23 cases (58.97%), 20/40 or better in 36 cases (92.30%), and worse than 20/40 in 3 cases (7.69%).
The incidence of infectious keratitis after surface ablation was 0.20%. Infectious keratitis is a potentially vision-threatening complication. Prompt and aggressive management with an intensive regimen of fortified antibiotic agents is strongly recommended. Proper management can preserve useful vision in most cases.
No author has a financial or proprietary interest in any material or method mentioned.
Effects of advanced surface ablations and intralase femtosecond LASIK on higher order aberrations and visual acuity outcome
2011, Saudi Journal of Ophthalmology
Citation Excerpt :
However, a difference was observed when any single procedure in the flap-off to flap-on group was compared (AlMahmoud et al., 2011). Also studies have cited comparable results for visual or refractive outcome at 3 months between Epi-LASIK and LASEK (Hondur et al., 2008; Teus et al., 2008) and thus we found that it would be reasonable to group the ASA procedures into flap-on and off. We are not aware of the previously published reports comparing epithelial flap-on and epithelial flap-off advanced surface ablations (ASA) techniques to intralase femtosecond LASIK (iLASIK) with detailed analysis of both ocular and corneal HOAs.
To study the changes in wavefront (ocular) and corneal higher order aberrations (HOAs) and visual acuity (VA) outcome following wavefront-guided advanced surface ablation (ASA) techniques and intralase femtosecond LASIK (iLASIK) in myopia treatment.
Ocular aberration and corneal topography of 240 eyes in the ASA techniques (this was equally divided into a flap-on group where the epithelial flap was preserved and reapplied to the photoablated stromal bed and a flap-off group when the epithelial flap was discarded during the procedure), and 138 eyes in the iLASIK group were obtained before and 3 months following treatment. The correlation of aberrations with best spectacle-corrected visual acuity was analyzed.
At 3 months, there was statistically significant (P < 0.001) surgically induced increase in spherical aberration (SA) in each of the techniques for both ocular and corneal analysis. iLASIK induced significantly less ocular and corneal HOAs (P < 0.001). The mean manifest refractive spherical equivalent was closer to attempted correction compared to other groups (P < 0.001). Eighty-three eyes (70%) of flap-on, 80 (67%) flap-off and 94 eyes (68%) in the iLASIK group achieved 20/20 uncorrected VA. Fifteen eyes (11%) accomplished 20/12.5 or better in iLASIK compared to 4 (3%) for flap-on and 7 (6%) for flap-off ASA group. Only the flap-off treatment showed a consistent correlation between the corrected aberrations and visual performance.
At 3 months, all procedures resulted in a significant increase in HOAs and SA. All had comparable 20/20 VA and 11% of iLASIK patients achieved 20/12.5 or better level.
Wavefront-guided epithelial laser in situ keratomileusis with mitomycin-C for myopia and myopic astigmatism: Flap-on versus flap-off technique
2011, Journal of Cataract and Refractive Surgery
Citation Excerpt :
This allows surgeons to efficiently dissect the epithelial sheet, separating it from Bowman layer, using standard LASIK surgical techniques without a significant learning curve.6,7 Using the epikeratome spares the cornea and conjunctiva from the possible toxic effects of alcohol exposure.4–12,14,15,A The thorough dissection of the epithelial sheet between the lamina lucida and lamina densa maintains an intact basement membrane and normal basal cell integrity, which are important predictors of postoperative pain and epithelial wound healing.4,5,10,12
To compare the postoperative pain, visual recovery, and outcomes of flap-on and flap-off epithelial laser in situ keratomileusis (epi-LASIK) with mitomycin-C (MMC).
Asian Eye Institute, Makati, Philippines.
Case-control study.
Patients with myopia up to 9.00 diopters had wavefront-guided epi-LASIK with MMC. After randomization, the epithelium was removed in 1 eye (flap off) and repositioned in the other eye (flap on). Questionnaires were used to evaluate postoperative pain and visual recovery in each eye during the first postoperative week. Visual results, refractive outcomes, contrast sensitivity, and higher-order aberrations (HOAs) were compared and analyzed.
The study evaluated 48 eyes. The mean pain scores were lower and better vision was perceived in the flap-off group during the first postoperative week. One year postoperatively, the mean uncorrected distance visual acuity was −0.088 logMAR in the flap-on group and −0.036 logMAR in the flap-off group (P=.918). The spherical equivalent was within ±0.50 D in 92% of eyes in both groups (P>.05). Forty-six percent in the flap-on group and 38% in the flap-off group gained 1 line of corrected distance visual acuity (P=.915). Contrast sensitivity tests under daytime and nighttime conditions were comparable. There was no statistically significant difference in the mean change in HOAs between groups.
Wavefront-guided epi-LASIK with MMC was effective, safe, and predictable in treating myopia and myopic astigmatism. Eyes that had flap-off epi-LASIK had less pain and faster visual recovery. Visual results, refractive outcomes, contrast sensitivity, and HOAs were comparable between groups.
No author has a financial or proprietary interest in any material or method mentioned.
Surface ablation techniques
2011, Journal of Cataract and Refractive Surgery
Citation Excerpt :
Hondur et al.76 also report similar UDVA results at all time points. In a study by Teus et al.,98 the efficacy index was significantly better in the LASEK group than in the epi-LASIK group—0.97 and 0.89, respectively. The UDVA was better in the LASEK group on days 1 and 30, but there was no statistically significant difference by month 3.
The ongoing quest for a safe, simple, effective, minimally invasive, and stable refractive surgical procedure to correct refractive errors has stimulated the development of surface ablation techniques and laser in situ keratomileusis. In this review, we describe the history, patient assessment, techniques, outcomes, and complications of surface ablation (photorefractive keratectomy, laser-assisted sub-epithelial keratectomy, epithelial laser-assisted in situ keratomileusis) and compare the results of various surface techniques. Surface ablation procedures will continue to evolve, with potential improvements in outcomes accompanying future sophisticated ablation profiles and laser technology.
No author has a financial or proprietary interest in any material or method mentioned.

View all citing articles on Scopus

Laura de Benito-Llopis, MD, PhD, graduated in 2000 with summa cum laude at Valencia University School of Medicine, Spain. She did her Ophthalmology residency at the Gregorio Marañón University Hospital in Madrid, Spain. Dr De Benito-Llopis obtained her PhD in laser surface ablation surgery with cum laude at the Universidad Complutense, Madrid. She works as a consultant at the Cornea and Refractive Surgery, Department at Vissum Madrid, Spain.

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Original articleComparison of Visual Results Between Laser-Assisted Subepithelial Keratectomy and Epipolis Laser In Situ Keratomileusis to Correct Myopia and Myopic Astigmatism

Purpose

Design

Methods

Results

Conclusions

Section snippets

Patients and Methods

Results

Discussion

J Cataract Refract Surg

Am J Ophthalmol

Surv Ophthalmol

J Cataract Refract Surg

J Cataract Refract Surg

J Cataract Refract Surg

Am J Ophthalmol

J Cataract Refract Surg

J Cataract Refract Surg

J Cataract Refract Surg

J Cataract Refract Surg

Ophthalmology

J Cataract Refract Surg

J Cataract Refract Surg

J Cataract Refract Surg

J Cataract Refract Surg

J Cataract Refract Surg

Laser in situ keratomileusis versus laser epithelial keratomileusis (LASIK vs. LASEK)

J Refract Surg

Prospective, paired comparison of laser in situ keratomileusis and laser epithelial keratomileusis for myopia less than −6.00 diopters

J Refract Surg

Comparison between LASEK and LASIK for the correction of low myopia

J Refract Surg

Original article
Comparison of Visual Results Between Laser-Assisted Subepithelial Keratectomy and Epipolis Laser In Situ Keratomileusis to Correct Myopia and Myopic Astigmatism