Epithelial ingrowth after laser in situ keratomileusis: clinical features and possible mechanisms

doi:10.1016/S0002-9394(02)01757-9

American Journal of Ophthalmology

Volume 134, Issue 6, December 2002, Pages 801-807

https://doi.org/10.1016/S0002-9394(02)01757-9 Get rights and content

Abstract

PURPOSE: To analyze the incidence, clinical course, and possible mechanisms of epithelial ingrowth after laser in situ keratomileusis (LASIK).

DESIGN: Interventional case series.

METHODS: Retrospective evaluation of 4,867 eyes of 2,502 patients who had LASIK. The type of microkeratome (LSK-One or MK-2000), corneal flap thickness, and clinical course were analyzed. We also compared the cutting characteristics of both microkeratomes in pig cadaver eyes by scanning electron microscopy.

RESULTS: The frequency of epithelial ingrowth was significantly greater in the MK-2000 (34 of 1,680 eyes; 2.0%) than the LSK-One group (30 of 3,187 eyes; 0.94%; P = .001). In 24 eyes (37.5%), blood, cell infiltration, ointment under the corneal flaps, or epithelial defect were detected at the area of epithelial ingrowth postoperatively. The incidence of epithelial ingrowth was correlated with the incidence of epithelial defect during surgery (P < .001) and with incidence of diffuse lamellar keratitis after surgery (P = .003). Flap thickness was thinner in eyes with epithelial ingrowth (126.0 ± 29.1 μm) compared with flap thickness in eyes without epithelial ingrowth (133.8 ± 27.3 μm; P < .001). Scanning electron microscopy showed clear differences in the appearance of flap edges created by the two types of microkeratomes. Epithelial ingrowth disappeared or remained unchanged in 54 eyes (90%) and progressed in six cases (10%).

CONCLUSIONS: Poor adhesion caused by excessive hydration due to epithelial defect as well as by foreign bodies between the flap stromal bed and thickness and morphologic characters of the corneal flap, depending on the type of microkeratomes, are related factors for development of epithelial ingrowth.

Section snippets

Design

This study was an interventional case series of patients with epthelial ingrowth occurring after LASIK.

Patients

Four thousand eight hundred sixty-seven eyes of 2,502 patients (1,452 male and 1,050 female; average age 34.5 ± 9.0 [SEM] years), who underwent myopic LASIK from May 1998 to March 2001 at Minamiaoyama Eye Clinic, were included in this study. The mean attempted correction was −6.08 ± 2.58 diopters. Sixty-four eyes (1.3%) of 54 patients (33 male and 21 female, average age 38.6 ± 9.0 [SEM] years) developed epithelial ingrowth. The slit-lamp examination findings, type of microkeratome used, and

Microkeratomes and flap thickness

Epithelial ingrowth was diagnosed in 30 eyes (0.94%) of the LSK-One group (3,187 eyes) and 34 eyes (2.0%) in the MK-2000 group (1,680 eyes). The frequency of epithelial ingrowth in the MK-2000 group was significantly higher than that in the LSK-One group (P = .001). When the incidence of epithelial ingrowth was compared among different types of heads, it was found that heads with lower estimated thicknesses were more likely to develop epithelial ingrowth (Table 1).

The corneal flap was

Discussion

The incidence of epithelial ingrowth after LASIK in the present study was 1.31%. Epithelial ingrowth was diagnosed within 1 month in 79% of eyes. These results are consistent with previous reports.2, 3, 4, 5, 6 Epithelial ingrowth mainly developed near the corneal flap margin, most often at the temporal edge.

Many findings were observed before the epithelial ingrowth. A loose epithelial layer or epithelial defect was detected significantly more often in cases with epithelial ingrowth than in

Acknowledgements

The authors thank Mrs. Chikako Sakai, Minamiaoyama Eye Clinic, for her help with statistical data analysis, and Yoshihisa Oguchi, MD, Department of Ophthalmology, Keio University School of Medicine, for supervising the electron microscopic observation.

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To report a case of metallic corneal foreign-body (CFB) penetrating the Laser in situ keratomileusis (LASIK) flap and its successful outcome. To highlight usefulness of Anterior Segment Optical Coherence Tomography (ASOCT) in diagnosis and management of post-LASIK CFB. To enumerate other similar cases published in literature.
A 30-year-old male presented to the emergency department of a tertiary eye care centre with a metallic CFB. He had undergone uneventful LASIK elsewhere 4-years back. He was unaware of any trauma. CFB removal was attempted elsewhere but abandoned as CFB appeared deeply embedded. ASOCT showed CFB had penetrated LASIK flap and lodged into midstroma, 207 μm deep. CFB was successfully removed in operation theatre along with the application of cyanoacrylate glue and bandage contact lens. A review of literature for CFB in post-LASIK patients was done through PubMed search.
Postoperative course was uncomplicated and there was a follow up period of 4 months. Vision improved to unaided 20/20 and N/6 from preoperative 20/60 and N/10. Review of literature of 24 patients showed Post-LASIK FB was more common in males (79%). None of the patients except for one had protective eye-wear. Metallic FB was most common followed by organic FB. Flap complications were present in seven patients. Diffuse lamellar keratitis (DLK) and epithelial ingrowth were the most common post-FB removal complications occurring in six (25%) and four (16.6%) patients respectively.
Post-LASIK patients with CFB need to be inspected for flap related complications. CFB can be successfully removed, although DLK, epithelial ingrowth, microbial keratitis, astigmatism, can occur post-CFB removal. ASOCT can delineate CFB and flap related details and thus is an additional useful imaging tool in such scenarios.
Disruption of ingrown epithelium via Nd:YAG laser or DIEYAG. A retrospective case series of Post-LASIK patients
2021, American Journal of Ophthalmology Case Reports
Citation Excerpt :
Thus, ingrowth is proposed to stem from poor adherence of the flap edge allowing epithelial cells to invade the lamellar surface.5,12,13 Only a small percentage of patients with epithelial ingrowth require surgical treatment, as epithelial growth in the corneal interface following LASIK is in most cases self-limiting.9,10,14–17 Surgical intervention is aimed at removing the existing cells in the interface and sealing the interface surface and resection edge to prevent further ingrowth.17
To describe in detail the technique used and results of disruption of ingrown epithelium via Nd:YAG laser (DIEYAG) after LASIK treatment and enhancement.
Epithelial ingrowth following laser in situ keratomileusis (LASIK) enhancement has the potential to cause significant refractive error and discomfort when allowed to progress. This retrospective case series following seven eyes after LASIK enhancement and one eye with flap trauma, assessed the effectiveness and safety of the disruption of ingrown epithelium via Nd:YAG laser. In all cases, we found that the progression of ingrown epithelium was eliminated. Using best spectacle corrected visual acuity and topography as our main outcome measures, we found that refractive error and visual disturbance caused by ingrowth stabilized or improved, with no subsequent complications identified.
The disruption of ingrown epithelium via Nd:YAG laser offers a safe and effective alternative to other treatments for epithelial ingrowth after LASIK treatment and enhancement.
Usefulness of bandage contact lenses in the immediate postoperative period after uneventful myopic LASIK
2018, Contact Lens and Anterior Eye
To determine the usefulness of a silicone-hydrogel bandage contact lens (BCL) in the immediate postoperative period after uneventful myopic laser in-situ keratomileusis (LASIK).
The study design was randomized but not masked and data collection was prospective. This study comprised 51 consecutive myopic eyes intervened by means of the LASIK technique to compensate their refractive error. Patients were randomly assigned to two different groups. The experimental group included 24 eyes of 12 patients that were fitted with a BCL immediately after the flap replacement. The control group included 27 eyes of 14 patients with no BCL. Patients were examined 24 h after the surgery; the experimental group was analyzed immediately after the extraction of the BCL. Postoperative uncorrected distance visual acuity (UDVA) and postoperative topographic indexes were compared to baseline in both groups.
The experimental group achieved worse results in the majority of the studied variables. Postoperative UDVA was worse in experimental group (p < 0.01). Likewise, corneal asphericity (Q) was significantly higher in experimental group (p = 0.024). Topographic indexes showed higher asymmetry in the corneal maps pertaining to experimental group. Specifically, the index of surface variance (ISV) (p = 0.017) and index of vertical asymmetry (IVA) (p = 0.031) were higher in experimental group. Also, the postoperative central corneal thickness (CCT) resulted in higher values for eyes pertaining to experimental group.
The fitting of a silicone-hydrogel BCL after uneventful LASIK provokes morphological changes in the ocular structures that may lead to a worse UDVA secondary to a higher postoperative CCT and corneal edema.
Comparison of 5468 retreatments after laser in situ keratomileusis by lifting the flap or performing photorefractive keratectomy on the flap
2018, Archivos de la Sociedad Espanola de Oftalmologia
Describir los resultados visuales del retratamiento tras láser in situ queratomileusis (LASIK) levantando el lentículo previamente o realizando queratectomía fotorrefractiva (PRK) sobre él, establecer si el riesgo de crecimiento epitelial de la interfase (CEI) es mayor cuanto más tiempo ha pasado entre el LASIK inicial y el retratamiento por levantamiento y determinar la incidencia de la opacidad corneal (haze) tras PRK.
Estudio retrospectivo de 4.077 pacientes (5.468 ojos) tratados mediante LASIK y retratamiento para estudiar los resultados visuales e identificar los casos de CEI y haze corneal.
Se estudiaron 5.196 ojos de 3.876 pacientes retratados de miopía levantando el lentículo y 272 ojos de 201 pacientes retratados mediante PRK en el lentículo. No se encontraron diferencias estadísticamente significativas entre los retratamientos en predictibilidad, eficacia y seguridad. Se encontró un total de 704 casos de CEI tras levantar el lentículo; se necesitó limpieza quirúrgica en 70. La limpieza quirúrgica disminuyó el índice de eficacia al compararlo con el de los pacientes con CEI que no precisaron limpieza (p = 0,01). Las diferencias en términos de seguridad y predictibilidad no fueron estadísticamente significativas. La incidencia de haze corneal tras la ablación de superficie sobre el lentículo previo fue del 14,34%, aunque ninguno de estos casos fue clínicamente relevante.
Los resultados visuales son similares entre los pacientes retratados mediante levantamiento del lentículo o mediante PRK. La incidencia de CEI levantando lentículo fue del 13,55%. La incidencia de CEI aumenta a medida que aumenta el tiempo entre el procedimiento primario y el retratamiento.
To assess visual outcomes of retreatment after laser in situ keratomileusis (LASIK) by lifting the flap or performing photorefractive keratectomy (PRK) on the flap, as well as to establish whether there was an increased risk of epithelial ingrowth (EIG) when LASIK and lifting of the flap are separated by a long time interval and to determine the incidence of corneal haze after PRK.
Retrospective study of 4077 patients (5468 eyes) who underwent LASIK and subsequent retreatment were reviewed in order to study their visual results and identify cases of EIG and corneal haze.
Enhancements included 5196 eyes from 3876 patients that were retreated by lifting the flap, and 272 eyes from 201 patients that were retreated by PRK on the flap. No statistically significant differences were found between the retreatments in terms of predictability, efficacy, and safety. A total of 704 cases of EIG were found after lifting the flap, for which surgical cleansing was necessary in 70. Surgical cleansing decreased the efficacy index when compared with patients with EIG who did not need cleansing (P=.01). Differences in terms of safety and predictability were not statistically significant. The incidence of corneal haze after ablation of the surface of the previous flap was 14.34%, although none of these cases were clinically relevant.
Visual outcomes were similar between patients who were retreated by lifting the flap and those who underwent PRK. The incidence of EIG when the flap was lifted was 13.55%. The incidence of EIG increases with the time elapsed between the primary procedure and retreatment.
Clinically significant laser in situ keratomileusis flap striae
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To describe the incidence, risk factors, and outcomes before and after irrigation of clinically significant laser in situ keratomileusis (LASIK) flap striae.
Multisurgeon multicenter standardized protocol practice.
Retrospective case-control series.
Eyes with striae necessitating flap relift and irrigation were identified. Preoperative, intraoperative, and postoperative variables were collected. Incidence, risk factors, and outcomes were assessed.
Of the 109 403 eyes that had LASIK, the incidence of striae-treated eyes was 0.79% (n = 875), with 8.7% irrigated the first hour after surgery. The preoperative spherical equivalent (SE) and ablation depth exponentially increased the striae risk (R² = 0.9674; P < .001). Striae induced a small hyperopic shift that reversed after the relift (mean 0.22 diopter [D] ± 0.52 [SD] versus −0.02 ± 0.45 D) (P < .001). After relifting, 68.0%, 87.0%, and 96.0% of eyes had an uncorrected distance visual acuity (UDVA) of 20/20, 20/25, 20/40 or better versus 25.0%, 55.0%, and 84.0%, respectively, before the relift (P < .001). Thirteen percent fewer striae-treated eyes achieved a UDVA of 20/20. Before relifting, 51.0% of striae eyes lost 1 or more lines of corrected distance visual acuity, with a safety index reverting to control values (0.99 versus 1.00) (P > .05) after the relift. A laser refractive enhancement was performed in 6.28% of relifted striae eyes versus 3.04% in nonstriae control eyes.
Flap striae requiring surgeon intervention occurred in 0.79% of eyes. Higher preoperative SE values were associated with an exponential increase risk for striae. Treatment by lifting and irrigation significantly improved the accuracy, efficacy, and safety to a level close to that of contralateral control eyes, although striae-treated eyes were more likely to need excimer laser retreatment.
Management of recurrent epithelial ingrowth following laser in situ keratomileusis with mechanical debridement, alcohol, mitomycin-C, and fibrin glue
2017, Journal of Cataract and Refractive Surgery
We report a consecutive case series of 4 eyes in which recalcitrant epithelial ingrowth after laser in situ keratomileusis was treated with flap lift, mechanical debridement of epithelial ingrowth, sequential application of alcohol 70.0% and mitomycin-C (MMC) 0.02% to residual epithelium and across the stromal bed and underside of the flap. Secure flap apposition was achieved with the use of fibrin glue. Clinically significant epithelial ingrowth did not recur in any eye; visual acuity improved in all cases. No complications were associated with this treatment. Mechanical debridement of epithelial ingrowth with additional application of alcohol 70.0% and MMC 0.02% along with tissue glue use for flap closure appears to be a safe and effective treatment for recalcitrant cases of clinically significant epithelial ingrowth.

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Epithelial ingrowth after laser in situ keratomileusis: clinical features and possible mechanisms

Abstract

Section snippets

Design

Patients

Microkeratomes and flap thickness

Discussion

Acknowledgements

Am J Ophthalmol

J Cataract Refract Surg

Am J Ophthalmol

Am J Ophthalmol

Prog Retin Eye Res