Late traumatic displacement of laser in situ keratomileusis flaps

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.].

Traumatic laser in situ keratomileusis flap dislocation with epithelial ingrowth, Propionibacterium acnes infection, and diffuse lamellar keratitis: A case report

RATIONALE

Traumatic flap dislocation might occur anytime after laser in situ keratomileusis (LASIK), but it is rarely concomitantly complicated with epithelial ingrowth, infectious keratitis, and diffuse lamellar keratitis altogether. Here we report a case of traumatic LASIK flap inversion with epithelial ingrowth, Propionibacterium acnes infection, and diffuse lamellar keratitis.

PATIENT CONCERNS

A 42-year-old man receiving bilateral LASIK surgery 10 years ago complained of right eye pain for 6 days after twig injury. Temporal flap inversion with epithelial ingrowth and dense infiltration at the interface were noted.

DIAGNOSES

Traumatic LASIK flap inversion with epithelial ingrowth, Propionibacterium acnes infection and diffuse lamellar keratitis.

INTERVENTIONS

Removal of corneal epithelium around the flap inversion site, flap lifting, scraping of epithelial ingrowth, removal of the dense infiltrate, alcohol soaking, interface irrigation with antibiotics, and flap reposition were performed. Diffuse lamellar keratitis was noted postoperatively. Culture of the infiltrate revealed P acnes. The infiltrate subsided and the cornea cleared up under topical antibiotics and steroid.

OUTCOMES

The visual acuity returned to 20/20. No recurrent epithelial ingrowth or infiltrate was noted during the follow-up.

LESSONS

This is the first report of Propionibacterium acnes keratitis after traumatic flap inversion. Although epithelial ingrowth, infectious keratitis, and diffuse lamellar keratitis all developed after the flap inversion, early recognition and proper intervention lead to a good result without sequels.

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.

Traumatic corneal flap displacement after laser in situ keratomileusis (LASIK)

Background

Laser in situ keratomileusis (LASIK) is the most common and popular procedure performed for the correction of refractive errors in the last two decades. We report a case of traumatic flap displacement with flap folding which occurred 3 years after LASIK was performed. Previous literature suggests that vision prognosis would be closely related to proper and prompt management of traumatic flap displacement with flap folding 3 years after LASIK.

Case presentation

A 23-year-old female presented to our hospital who had undergone uneventful LASIK in both eyes 3 years prior. Unfortunately, she had suffered a blunt trauma in her right eye in a car accident. A late onset of corneal flap displacement was found with upper and lower portion of the flap being folded inside the corneal bed. Surgical intervention for debridement with subsequent reposition of corneal flap was performed as soon as possible in the operating room. A bandage contact lens was placed, and topical antibiotic and corticosteroids were given postoperatively. Two days after the operation, the displaced corneal flap was found to be well attached smoothly on the corneal bed without folds. The best-corrected visual acuity was 6/6 with refraction of −0.75 D to 1.0 D ×175° in her right eye 1 month later.

Literature review

We reviewed a total of 19 published cases of late-onset traumatic flap dislocations or displacements after LASIK with complete data from 2000 to 2014.

Conclusion

Traumatic displacement of corneal flaps after LASIK may occur after blunt injury with specific direction of force to the flap margin, especially tangential one. According to the previous literature, late-onset traumatic flap displacement may happen at any time after LASIK and be caused by various types of injuries. Fortunately, good visual function could mostly be restored with immediate and proper management.

Mechanisms for acute corneal hydrops and perforation

Acute corneal hydrops (ACH) and perforation in corneal thinning diseases are the consequences of exposure to distending intraocular pressure (IOP) forces that are in excess of corneal resistance to them. Apart from thinning, resistance to these forces may be reduced by disease-related tissue changes, such as corneal scarring, which could lower resistance to IOP. Eye rubbing trauma has sometimes been found to be associated with ACH and perforation. This association is not surprising given that the combination of rubbing-related mechanical tissue trauma and the associated increased distending stress of higher IOP seem likely to increase the risk of complications. Many cases of ACH and perforation are described as spontaneous, but this classification may be the consequence of not considering the multiple potential mechanisms for IOP elevation such as coughing, sneezing, nose blowing, and sneeze suppression in addition to those related to eye rubbing/wiping/massaging/touching as well as changes in body orientation, strenuous exercise, and wearing swimming goggles for example. Classification of ACH or perforation as spontaneous may lead patients to assume that nothing can be done to avoid these complications. Patients with corneal thinning diseases who are counseled regarding the potential precipitating mechanisms for IOP elevation will have the opportunity of reducing exposure to them and the risk of the associated complications. In addition, when ACH or perforation occur, faster resolution of edema and wound healing may depend on reducing potentially exacerbating exposures to mechanisms for IOP elevation.

Traumatic flap dislocation 10 years after LASIK. Case report and literature review

We report a case of traumatic partial flap dislocation 10 years after uneventful laser in situ keratomileusis (LASIK). The patient was treated bilaterally for hyperopia and astigmatism with LASIK. A superior-hinged corneal flap was created using the Moria M2 microkeratome (Moria SA, Antony, France) and the surgery was uneventful. Ten years later, partial flap dislocation was diagnosed after mild trauma. This case suggests that flap dislocations can occur during recreational activities up to 10 years after surgery. Full visual recovery is achievable if the case is managed promptly. Further studies should evaluate the potential protective role of an inferior hinge during LASIK.

Epipolis-Laser In Situ Keratomileusis Discarding Epithelium Versus Laser In Situ Keratomileusis for Myopia and Myopic Astigmatism in Asian Eyes

PURPOSE

To compare long-term safety, efficacy, predictability, and visual outcomes of epipolis-laser in situ keratomileusis (epi-LASIK) discarding epithelium versus LASIK in Asian eyes.

DESIGN

This was a prospective, randomized, bilateral case series.

METHODS

This study included 166 eyes of 83 patients with myopia and myopic astigmatism who received epi-LASIK in 1 eye and LASIK in the contralateral eye. Automated separation of the epithelium was performed with epi-K™, and LASIK was performed with M2 microkeratome using 90-μm calibrated heads. Patients were seen post-operatively at 1 and 3 days, 1 week, and on days 1, 3, 7 at 1, 3, 6, and 12 months. Uncorrected visual acuity, best corrected visual acuity, spherical equivalent (SE), contrast sensitivity, total higher-order aberration, corneal sensitivity, and clarity were analyzed.

RESULTS

Mean preoperative SE was -4.26 (SD, 1.64) diopters (D) in epi-LASIK and -4.27 (SD, 1.63) D in the LASIK group. Twelve months after surgery, mean SE was 0.04 (SD, 0.40) and 0.11 (SD, 0.30) D, respectively. There was no significant difference in uncorrected visual acuity (P = 0.451), SE (P = 0.157) and contrast sensitivity between groups at the 1-year follow-up (P > 0.05). During 6 months after operation, corneal sensitivity values were significantly lower in the LASIK group (P < 0.05). No eye lost line of best corrected visual acuity in both groups. In epi-LASIK eyes, there was no haze in 97.5% and haze grade 1 in 2.5% at 3 months postoperatively. From 6 months onward, alls corneas were clear.

CONCLUSIONS

Epi-LASIK was safe, predictable, and effective and may be considered an alternative for LASIK.

OCT visualization of corneal structural changes in traumatic dislocation of LASIK flap

A 45-year-old woman presented with a traumatic laser-assisted in situ keratomileusis (LASIK) flap dislocation in the right eye. Anterior segment optical coherence tomography (OCT) showed the presence of macrostriae, flap stromal edema, epithelial hyperplasia between the striae and epithelial ingrowth. The flap was surgically repositioned with optimal visual recovery. Anterior segment OCT can efficiently visualize corneal structural changes associated with LASIK flap dislocation.

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.

Photorefractive keratectomy after late traumatic LASIK flap loss

PURPOSE

To present a case of photorefractive keratectomy (PRK) after late traumatic LASIK flap loss.

METHODS

The initial LASIK procedure was performed in 2003 with a Moria M2 microkeratome and NIDEK EC-5000 excimer laser using a 5.0/9.0-mm aspheric ablation pattern, resulting in 20/20(+) uncorrected distance visual acuity (UDVA) and plano refraction. Traumatic flap loss of the right eye occurred in 2007. The patient was treated for the trauma, and PRK for -5.00 -1.25 × 090° was performed 2 months later.

RESULTS

Posttraumatic flap loss UDVA was 20/200 in the right eye, with corrected distance visual acuity (CDVA) of 20/25(+2). After PRK with mitomycin C (MMC), UDVA was 20/15 2 months postoperatively and was maintained through the last postoperative follow-up in 2010 (approximately 3 years after PRK).

CONCLUSIONS

Treating a patient with traumatic LASIK flap loss can be done by careful, conservative treatment of the abrasion followed by correction of the refractive error using PRK with MMC.

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.

Management of chronic habits of abnormal eye rubbing

A review of the provocations and the consequences of chronic habits of abnormal rubbing indicates a range of possible adverse responses. Gentle rubbing may double intraocular pressure. However, the combination of tight eye closure and forceful rubbing may raise intraocular pressure to more than 10 times normal levels. The possibility that, in susceptible individuals, chronic habits of abnormal rubbing may lead to the development or progression of keratoconus has been extended to the possibility of rubbing related adverse responses in other diseases and conditions. The adverse consequences of rubbing appear to be active processes, in contrast to the apparent passive nature of any recovery from those responses. Avoidance of the possibility of permanent adverse changes is clearly preferable. However, advice to avoid rubbing may not be successfully followed. Education and counseling appear to be the foundations for helping patients to control chronic habits of abnormal rubbing. An instrument has been developed as the basis for patient education and counseling for this purpose. It is intended as a take-home document which might have relevance to other family members. The widening of the application of this form of patient education to all members of a family, and a wider range of conditions, may produce beneficial synergy with advantage to patients who may have the most to gain from controlling chronic habits of abnormal rubbing.

Unusual complication after laser in situ keratomileusis: Eyelash under the flap

We report a 70-year-old man who had uneventful laser in situ keratomileusis (LASIK) to correct the refractive error in the right eye. The patient returned 5 weeks later complaining of irritation and pain in that eye. Examination revealed an eyelash under the edematous LASIK flap with surrounding infiltrates. The anterior chamber was quiet. The flap was lifted and the eyelash removed. Epithelial cells were removed from the flap interface. Postoperatively, the patient developed a mild diffuse lamellar keratitis that resolved rapidly with topical corticosteroid treatment. At 5 months, the uncorrected visual acuity was 20/20(-2), with mild haze in the inferior interface. Large, visually significant foreign bodies under a LASIK flap should be promptly removed for a good visual outcome. To our knowledge, this is the first report of a post-LASIK complication due to an eyelash under the flap.

Traumatic Corneal Flap Dislocation One to Six Years After LASIK in Nine Eyes With a Favorable Outcome

PURPOSE

To report our experience treating eye trauma after LASIK refractive surgery.

METHODS

Nine eyes of eight patients (one woman and seven men) were treated for ocular trauma: blunt trauma (n=5), sharp instrument trauma (n=2,) and trauma from inflation of automobile air bags during a traffic accident (n=2). The time from LASIK varied between 3 months and 6 years. All patients were hospitalized as a result of severe decrease in visual acuity and pain.

RESULTS

Seven of nine LASIK flaps had some degree of dislocation and were lifted, irrigated, and repositioned. Two flaps were edematous without dislocation. Intensive topical steroids and antibiotics were used in all patients up to 3 weeks after trauma. Three months after trauma, five eyes regained their pre-trauma visual acuity (between 20/20 and 20/40), and three eyes lost one line of best spectacle-corrected visual acuity.

CONCLUSIONS

Trauma occurring several months or years after LASIK may cause flap injury. Adequate and prompt treatment usually is successful.

Late-onset Traumatic Dislocation With Central Tissue Loss of Laser In Situ Keratomileusis Flap

PURPOSE

We report the occurrence and outcome of a severe late-onset traumatic dislocation of a laser in situ keratomileusis (LASIK) flap with loss of central flap tissue.

METHODS

Case report.

RESULTS

A 40-year-old woman underwent uncomplicated bilateral LASIK surgery, followed 5 years later by an enhancement procedure in both eyes. Ocular trauma with a power sander occurred 6 years after LASIK and 1 year after the enhancement procedure. The flap was found to have an almost complete tear from the nasal hinge and a central tissue defect. After irrigating, repositioning, and stabilizing the flap with 2 nylon sutures, a bandage contact lens was placed. The patient was treated with topical antibiotic and steroid drops. Stage 2 diffuse lamellar keratitis developed, which responded to topical treatment. Ten weeks after injury, the patient regained an uncorrected visual acuity of 20/20-1.

CONCLUSION

Late-onset trauma to the LASIK flap can result in flap dehiscence and tissue loss. Prompt and appropriate management can lead to an excellent visual outcome even in severely traumatized dislocated LASIK flaps.

Stability of the laser in situ keratomileusis corneal flap in rabbit eyes

PURPOSE

To quantify the force required to dislodge a laser in situ keratomileusis (LASIK) corneal flap in rabbits and correlate that force with sources of injury to LASIK corneal flaps in humans.

SETTING

Animal Vivarium and Department of Ophthalmology, Naval Medical Center, San Diego, California, USA.

METHODS

Corneal flaps were cut in 56 eyes of 30 rabbits. A -8.00 diopter excimer ablation was also performed in 32 of the eyes. Injury testing, using a burst of CO2 from a modified paintball gun, was conducted from 1 to 9 days postoperatively. Impact force was compared to that generated by mechanical trauma (fingers and a small tree branch) striking a force gauge.

RESULTS

Of 43 eyes tested for injury, flaps could not be dislocated in 11 eyes (26%). There was no significant difference between eyes treated with flap only and those that also had ablation. When flaps were dislodged, the required force generally resulted in extensive intraocular injury. There was no significant difference between the force required for flap dislocation on postoperative days 1 and 9.

CONCLUSIONS

In rabbits, LASIK corneal flaps were very resistant to high-speed wind trauma as early as 24 hours postoperatively. Flap stability was robust prior to the formation of collagen scar tissue, probably due to epithelial bridging at the edge of the flap and an osmotic gradient across the flap-stromal bed interface. Although this study used a rabbit model, it seems likely that both these flap adhesion mechanisms would also provide stability to the LASIK flap in humans.

Late Traumatic Flap Dislocations After LASIK

PURPOSE

To report the management and outcome of late onset traumatic dislocation of LASIK flaps.

METHODS

This retrospective, interventional case series presents three patients with late onset LASIK flap dislocation following mechanical trauma 1 to 7 years postoperatively.

RESULTS

In all cases, the flap was surgically repositioned. Epithelial ingrowth was removed and diffuse lamellar keratitis was treated with an intensive steroid regimen. All patients returned to their preoperative best spectacle-corrected visual acuity. Aggressive steroid treatment during the perioperative period and meticulous handling of the epithelium are important in preventing further recurrence.

CONCLUSIONS

Laser in situ keratomileusis flaps may experience mechanical dislocation as late as 7 years postoperatively. Diffuse lamellar keratitis and epithelial ingrowth are associated with flap dislodgment.

Traumatic Late Flap Dehiscence and Enterobacter Keratitis Following LASIK

PURPOSE

To report a case of traumatic flap dehiscence and Enterobacter keratitis 34 months after LASIK.

METHODS

A 36-year-old man sustained a flap dehiscence following traumatic right eye gouging by a seagull claw. He presented the following day with uncorrected visual acuity (UCVA) in the affected eye of 3/200 and organic foreign body deposits underneath the flap. Systemic and topical antibiotics were administered and urgent surgical debridement and replacement of the LASIK flap was performed. An Enterobacter species was cultured from an intraoperative swab.

RESULTS

After a prolonged postoperative course, including administration of topical ofloxacin, tobramycin, chloramphenicol, and dexamethasone, UCVA returned to 20/20.

CONCLUSIONS

Good visual outcome after early debridement and appropriate antibiotics was achieved. Patients should be injury advised to seek prompt ophthalmic consultation after LASIK.

Cyanoacrylate repair of laser in situ keratomileusis corneal flap perforation by a snake bite

A 30-year-old man who had laser in situ keratomileusis (LASIK) for myopia 1 year earlier developed a corneal perforation in the left eye from a boa constrictor. The patient presented to the emergency room, and a small corneal perforation just outside the visual axis was diagnosed within the LASIK flap. Cyanoacrylate adhesive was used to close the corneal perforation. The patient went on to full visual recovery with an uncorrected visual acuity of 20/20. This is the first reported case of a penetrating corneal injury from a serpent in an eye that had LASIK. Cyanoacrylate may be used to repair small traumatic corneal perforations with a favorable visual outcome in eyes that have had LASIK.

Late-onset repetitive traumatic flap folds and partial dehiscence of flap edge after laser in situ keratomileusis

A 25-year-old woman had traumatic flap folds and partial dehiscence of the flap edge in the right eye 5 and 30 months after laser in situ keratomileusis. The period from injury to treatment was 4 hours and 9 days, respectively. With the first injury, the flap was lifted and stretched with moistened sponges to clear the folds. With the second injury, the folds were hard so the flap was lifted and sutured to stretch the folds. The patient recovered visual acuity within 2 weeks.