Late Traumatic Flap Dislocations After LASIK

Corneal foreign body post laser in-situ keratomileusis: Diagnosis, management, outcome and review of literature

Purpose

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.

Method

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.

Result

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.

Conclusion

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.

Efficacy and Safety of Surgically Managed Late Traumatic LASIK Flap Displacements in a Study of 66 Cases

PURPOSE

To evaluate safety and efficacy in the management of flap displacement after laser in situ keratomileusis (LASIK) and subsequent complications.

METHODS

This was a retrospective study performed using data recorded at the center's database from October 2002 to August 2021. Efficacy and safety were both converted to binary outcomes (loss of one or more lines and no change or gain in lines of visual acuity). The effects of time from surgery to complication and from complication to repair were assessed and the odds ratios and probabilities were calculated. The same procedure was applied to investigate the effect of these temporal variables on complications.

RESULTS

A total of 66 eyes with late traumatic LASIK flap displacements were studied. Efficacy remained unchanged in 48 patients (64 eyes, 75%), and safety remained unchanged in 53 patients (59 eyes, 90%). Sixty-six patients (64 eyes, 100%) achieved visual acuity values of 20/40 and 45 patients (64 eyes, 70.3%) achieved values of 20/20. The flap displacement was resolved in the first 24 hours (SD ± 0.1 days). Surgery was performed in 58 patients (65 eyes, 90%). Epithelial ingrowth was the most frequent complication. Patients who underwent surgery tended not to lose lines (P = .05). The risk of developing epithelial ingrowth increases with time after LASIK surgery until traumatic flap displacement (odds ratio: 1.001; P < .001). The prevalence of dislocation during the study period was 0.012%.

CONCLUSIONS

Visual safety values were favorable after resolution of the flap complication. Immediate surgical management leads to better visual efficacy, and the time between LASIK and trauma increases the risk of epithelial ingrowth after flap displacement. [J Refract Surg. 2022;38(4):270-276.].

LASIK flap stability after severe ocular injury

Purpose

To report two cases of LASIK flap stability after severe ocular trauma.

Observations: Two patients suffered open globe injuries several years after undergoing uneventful LASIK with femtosecond laser corneal flap. Both underwent primary ruptured globe repair, during which no LASIK flap dislocation was identified. Histopathologic examination of one of the cornea specimens confirmed an intact LASIK flap.

Conclusion and Importance

In these cases, the femtosecond LASIK flap remained in place despite significant injury to the cornea. The presence of a femtosecond LASIK flap did not complicate surgical management of the injury, and did not contribute to the patient's loss of BCVA.

Late-onset diffuse lamellar keratitis following laser in situ keratomileusis

OBJECTIVE

To analyze 12 cases of late-onset diffuse lamellar keratitis (DLK) following uncomplicated LASIK and propose a method of management.

DESIGN

Retrospective observational case series, literature review.

PARTICIPANTS

Patients who developed late-onset DLK following LASIK.

METHODS

Retrospective chart review of all patients with late-onset DLK from January 2014 to August 2015. Data collected included demographic information, probable cause of DLK, stage of DLK, baseline examination, treatment, clinical course, outcomes, complications, and last follow-up examination. Review of relevant literature included searching for all prior cases and case series relating to "diffuse lamellar keratitis," "late-onset DLK," "Secondary Sands," and "delayed-onset DLK" by searching PubMed with these search terms.

RESULTS

Twelve eyes of 11 patients presented with late-onset DLK following LASIK. Onset ranged from 8 months to 17 years following LASIK. Stage of DLK ranged from stage I to III, and all patients responded well to aggressive corticosteroids without lifting of the LASIK flap. Final visual acuity for stage I/II and III eyes did not demonstrate a significant difference (p = 0.218). DLK resolved by a mean of 4.86 weeks for all eyes.

CONCLUSION

Late-onset DLK can present at any time following LASIK with a wide range of inciting factors causing a nonspecific (and likely immune-related) inflammatory reaction. Based on our findings, aggressive oral and topical corticosteroids should be tried before lifting the LASIK flap as long as infection is not suspected or inciting debris is not seen in the flap because the vast majority resolve with such therapy.

Satisfactory clinical outcome following delayed repositioning of a traumatic post-LASIK flap with dislocation and shrinkage managed by irrigation, stretching, and debridement

OBJECTIVE

To report surgical management and favorable outcome in a case with delayed repair of traumatic laser in situ keratomileusis (LASIK) flap dislocation with shrinkage and folds.

METHODS

A 30-year-old man with a five-year history of bilateral LASIK experienced blunt trauma to his right eye followed by decreased vision for 5 weeks. The surgical management included initially softening the flap by irrigation with balanced salt solution (BSS). The shrinkage folds were carefully and gently stretched by scraping with a 26-gauge cannula accompanied by BSS irrigation. All of the epithelial ingrowth on the flap inner surface and on the bed was thoroughly debrided by scraping and irrigation. After the flap was repositioned to match its original margin, a soft bandage contact lens was placed.

RESULTS

At his initial visit, slit-lamp microscopy and optical coherence tomography (OCT) showed shrinkage of the LASIK flap with an elevated margin approximately 3 mm above the original position. The flap covered half of the pupil and had multiple horizontal folds. Two months after surgery, the flap remained well positioned with only faint streaks in the anterior stroma. The uncorrected visual acuity of the right eye was 20/20 with a manifest refraction of Plano.

CONCLUSIONS

For delayed repair of traumatically dislocated LASIK flaps, sufficient softening by BSS, stretching the shrinkage folds, and thorough debridement of ingrowth epithelium enable resetting the flap and provide satisfactory results.

Management of long-standing partially torn and flipped laser in situ keratomileusis flaps

We describe 2 cases of traumatized and torn laser in situ keratomileusis (LASIK) flaps, partially flipped anteriorly or posteriorly, fixed for 8 months or 4 months, and accompanied by epithelial ingrowth. The 2 patients had had uneventful bilateral LASIK 6 years and 1 year before the trauma. In Case 1, the anteriorly flipped flap was removed with transepithelial phototherapeutic keratectomy. Next, mitomycin-C 0.04% was applied for 30 seconds. In Case 2, the portion of the flap that was flipped posteriorly and buried under the remaining intact LASIK flap was restored to its original normal position and epithelial ingrowth was removed mechanically with a microcurette. Irrigation with 20% ethanol was performed to inhibit the recurrence of interfacial epithelial ingrowth. The stretched amniotic membrane overlay over the cornea and sclera was sutured tightly to the episclera as the biologic pressure patch for the inhibition of epithelial re-ingrowth. Good visual acuity was restored in both cases.

FINANCIAL DISCLOSURE

No author has a financial or proprietary interest in any material or method mentioned.

Surgical management of traumatic LASIK flap dislocation with macrostriae and epithelial ingrowth 14 years postoperatively

Fourteen years after uneventful laser in situ keratomileusis (LASIK), a 59-year-old woman presented after suffering blunt trauma to her left eye 5 weeks earlier. The injury resulted in traumatic flap dislocation, epithelial ingrowth, and significant macrostriae. Following epithelial removal, the flap was hydrated with sterile water, facilitating reduction of the macrostriae and reapproximation without the need for suture placement. The postoperative course was uneventful, and at 1 month, the epithelial ingrowth and macrostriae had resolved and the uncorrected distance visual acuity was 20/30. This case represents the longest documented interval from LASIK surgery to traumatic flap dislocation. We describe our surgical approach to the management of this type of injury and present a video illustrating the technique.

Bilateral corneal opacities in a LASIK patient after the use of titanium eye shields

We report a case of bilateral corneal opacities in a laser in situ keratomileusis (LASIK) patient who subsequently had carbon dioxide (CO(2)) laser skin resurfacing. The presumed etiology of the visually significant corneal opacities was late-onset diffuse lamellar keratitis (DLK), secondary to traumatic corneal abrasions from the use of metal eye shields. The DLK went untreated for 1 month, resulting in permanent interface scarring and a corrected distance visual acuity of 20/30 in the patient's right eye and 20/20 in the left eye. We think patients who have had LASIK and are planning to have CO(2) laser skin resurfacing or any procedure that uses protective metal eye shields should be counseled about the risk for late-onset DLK as a potential complication. This warning is particularly germane now as an increasing number of patients who have had LASIK are entering the decades of life when cosmetic surgery is most likely to be sought.

FINANCIAL DISCLOSURE

Neither author has a financial or proprietary interest in any material or method mentioned.

Incidence of diffuse lamellar keratitis after LASIK with 15 KHz, 30 KHz, and 60 KHz femtosecond laser flap creation

PURPOSE

To compare the incidence of diffuse lamellar keratitis (DLK) after laser in situ keratomileusis (LASIK) with flap creation using the 15 kHz (FS15), 30 kHz (FS30), or 60 kHz (FS60) femtosecond laser.

SETTING

University-based academic practice, Ann Arbor, Michigan, USA.

DESIGN

Retrospective comparative case series.

METHODS

Consecutive myopic LASIK cases performed between January 1, 2005, and June 1, 2007, using the IntraLase FS15, FS30, or FS60 femtosecond laser for flap creation were reviewed. Preoperative clinical characteristics, treatment parameters, and intraoperative and postoperative complications were recorded. Statistical comparisons were made using repeated measures analysis, analysis of variance, chi-square, and Fisher exact tests.

RESULTS

Five hundred twenty eyes of 274 patients were included in the study. One hundred seventy-six eyes (93 patients) were treated with the FS15 laser, 180 eyes (93 patients) with the FS30 laser, and 164 eyes (89 patients) with the FS60 laser. Seventeen eyes (10%) in the FS15 laser group, 24 eyes (13%) in the FS30 laser group, and 23 eyes (14%) in the FS60 laser group developed DLK. There was no statistically significant difference in the incidence of DLK between the 3 groups (P = .68).

CONCLUSION

There was no significant difference in the incidence of DLK between the FS15, FS30, and FS60 groups.

Traumatic Flap Striae 6 Years After LASIK: Case Report and Literature Review

Purpose:

To report a case of traumatic flap striae without flap dislocation 6 years after LASIK and provide a literature review of surgical flap striae, late traumatic flap striae, and their management.

Methods:

A 28-year-old man presented with late traumatic flap striae without concurrent flap dislocation, which closely approximated the longest reported interval between LASIK and the development of flap striae.

Results:

In the absence of flap dislocation, the finding of striae alone was subtle and went undetected initially. The flap was successfully refloated, stretched, and smoothed with recovery of 20/20 vision.

Conclusions:

Traumatic LASIK flap complications may occur many years after the original procedure. This report presents the first case of late traumatic flap striae without concurrent flap dislocation. Proper management can restore good visual function.

Flap lift and repair of postoperative laser in situ keratomileusis complications at the slitlamp

We describe a technique to treat flap complications after laser in situ keratomileusis while seated at the slitlamp biomicroscope. After topical anesthesia is applied to the cornea, a blunt corneal spatula is used to reflect the flap only to the extent necessary for epithelial debridement. A corneal rake or spatula is then used to remove retained epithelial cells from the stromal bed and underside of the flap. The epithelium is then debrided 1.0 mm to 2.0 mm outside the flap gutter. The increased depth perception with a slit beam greatly improves visualization and identification of the presence of residual epithelial cells or leftover debris after scraping. The slit beam also aids in proper repositioning of the flap after the procedure.

FINANCIAL DISCLOSURE

No author has a financial or proprietary interest in any material or method mentioned.

Late traumatic LASIK flap loss during contact sport

Three years and 5 months after uneventful laser in situ keratomileusis, the left eye of a 39-year-old man was struck by the finger of a friend while the two were practicing karate, resulting in loss of the flap. The patient had performed this contact sport regularly for years. When last seen 16 weeks after injury, the best corrected visual acuity in the left eye was 20/40 with -1.75 -0.50x30. Mild central corneal haze was observed under slitlamp examination, the flap was missing, and the patient complained of dysphotopsia. Pachymetry in the left eye was 394 mum, with an irregular corneal contour. Flap loss is a serious complication because severe irregular astigmatism and unpredictable refractive change can occur. This case highlights the vulnerability of flaps to trauma even late postoperatively.

Outcomes of Wavefront-Optimized Surface Ablation

PURPOSE

To compare early visual outcomes after wavefront-optimized advanced surface ablation (ASA) with those after wavefront-optimized LASIK.

DESIGN

Retrospective comparative series.

PARTICIPANTS

One hundred thirty-six eyes undergoing ASA and 136 preoperative refraction-matched eyes undergoing LASIK from June 2004 through October 2005.

METHODS

Database review of preoperative characteristics, including patient age, gender, refraction, and central corneal pachymetry; perioperative information, including type of surgery, flap thickness (for LASIK cases), ablation depth, and residual stromal bed thickness; and postoperative information, including uncorrected visual acuity (UCVA) at 1 day, 1 week, 2 weeks, and 3 months, refraction at 3 months, and complications. All ASA patients had topical mitomycin C applied intraoperatively.

MAIN OUTCOMES MEASURES

Postoperative UCVA, best spectacle-corrected visual acuity (BSCVA), spherical equivalent (SE) refraction, speed of visual recovery, and postoperative complications.

RESULTS

Surface ablation patients were younger (35.4 years vs. 39.8 years, P = 0.0002) and had thinner corneas (514 microm vs. 549 microm, P<0.0001) preoperatively. Average UCVA was significantly better after LASIK at 1 day (20/26.8 vs. 20/50.4, P<0.0001) and 2 weeks (20/24.4 vs. 20/33.3, P = 0.0002) postoperatively. However, by 3 months postoperatively, UCVA was better after ASA (20/20.8 vs. 20/22.7, P = 0.05), and 81.5% of patients achieved 20/20 or better UCVA after ASA, compared with 70.5% after LASIK (P = 0.05). More ASA eyes had postoperative UCVA that achieved or surpassed preoperative BSCVA than LASIK eyes (66% vs. 41.6%, P<0.0001). There were 53 patients who underwent bilateral simultaneous ASA. By 1 week, 87.5% had 20/40 or better UCVA in at least one eye and 62.5% had 20/40 or better UCVA in both eyes. By 2 weeks, 86.8% had 20/40 or better UCVA in one eye and 82.6% had 20/40 or better UCVA in both eyes.

CONCLUSION

Initial visual recovery is more rapid after LASIK; however, by 3 months postoperatively UCVA and SE refractions were better after ASA. Advanced surface ablation is an effective alternative to LASIK, and based on early visual recovery, bilateral simultaneous surface ablation is a reasonable alternative to sequential surgery for the majority of patients.