Traumatic Dislocation of LASIK Flaps 4 and 9 Years After Surgery

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.

Recurrent prolapse of toric implantable collamer lens after blunt ocular trauma under mesopic conditions

Implantable collamer lenses (ICL) carry a risk of prolapse caused by direct ocular trauma, especially in mesopic conditions and when oversized ICLs are implanted. We recommend early surgical repositioning, as well as patient education that encourages goggle use during active sports.

Bandage Contact Lens Application Reduces Fibrotic Wound Healing of Flap Margins after FS-LASIK: A Prospective Randomized Clinical Trial

Purpose

To assess the efficacy of applying bandage contact lens (BCL) in reducing the fibrotic healing response of flap margins following femtosecond laser in situ keratomileusis (FS-LASIK).

Methods

In this prospective, randomized, interventional, observer-masked trial, 41 patients (82 eyes) with myopia and/or myopic astigmatism were scheduled to undergo FS-LASIK. After surgery, patients were fitted with a BCL in one eye (BCL eyes, n=41) but not in the contralateral eye (control eyes, n=41), following randomized allocation of the BCL to the left or right eye of each patient. The BCL was left in place overnight and removed the following morning. All eyes subsequently received standardized postoperative treatments. Patients were followed up for 6 months. We evaluated patients' self-reported postoperative symptom scores for pain, photophobia, tearing, and foreign-body sensation. At 6 months after surgery, we examined the corneal flap margin and adjacent regions, and photographed them using slit-lamp biomicroscopy, to subjectively evaluate the wound healing response.

Results

Postoperative pain and photophobia were milder in the BCL group than in the control group (P=0.041 and P=0.003, respectively), but patients felt more foreign-body sensation in the eye with a BCL than in the control eye (P=0.001). There was no significant difference in tearing score between BCL eyes and control eyes (P=0.118). Regarding the fibrotic healing response of the flap margin, control eyes showed a wide, bright peripheral circumferential band with a spiculated edge and high reflectivity; conversely, BCL eyes showed a markedly narrower and smoother peripheral circumferential band, with a less spiculated edge and lower reflectivity (P < 0.001).

Conclusion

Patients felt less discomfort in eyes treated with a BCL after FS-LASIK than in control eyes. BCL-treated eyes also had a less intense wound healing response at the flap margins than control eyes in some of patients. BCLs may merit consideration as a treatment option after FS-LASIK for special patients. This trial is registered with ChiCTR1800016579.

Case Report: Penetrating Corneal Injury Under an Intact Laser-assisted in Situ Keratomileusis Flap

SIGNIFICANCE

As the prevalence of post-laser-assisted in situ keratomileusis (LASIK) patients rises, recognition of possible traumatic complications and their management in this population becomes increasingly relevant. Penetrating injuries and intraocular foreign bodies are possible in post-LASIK corneas despite an intact anterior corneal surface. However, with prompt recognition and treatment, excellent visual recovery can be achieved.

PURPOSE

The purpose of this study was to report an interesting case of a penetrating foreign body through an intact LASIK flap.

CASE REPORT

A 48-year-old man presented to an outside provider with right eye pain after his eye was struck by a tree branch. His ocular history was notable for uncomplicated LASIK surgery 4 years before presentation. On initial examination, the patient was diagnosed as having a small corneal abrasion and hyphema. Despite appropriate therapy, his eye continued to subjectively and objectively worsen. Follow-up examination after the injury was notable for a new dense hypopyon. Because of concern for secondary infection, the patient was referred urgently for further evaluation. Upon referral, the patient was noted to have a dense, fibrinous mass located inferiorly in the anterior chamber. Although the cornea was edematous temporally with deep folds, the anterior corneal surface appeared intact without evidence of laceration or flap displacement. Concern for endophthalmitis prompted anterior chamber washout, where a large vegetative foreign body was recovered despite an intact anterior corneal surface and LASIK. Post-operative anterior-segment optical coherence tomography after resolution of the corneal edema confirmed the presence of a well-aligned penetrating tract through the posterior stromal bed underneath the LASIK flap. Epithelial ingrowth that developed within the post-operative period further affirmed the initial tract of the penetrating foreign body.

CONCLUSIONS

This case illustrates a novel complication after trauma in a post-LASIK patient, describes possible management, and underscores the care that must be taken when assessing patients with a history of LASIK surgery.

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.

Corneal tissue interactions of a new 345 nm ultraviolet femtosecond laser

PURPOSE

To assess the suitability of a new 345 nm ultraviolet (UV) femtosecond laser for refractive surgery.

SETTING

Department of Ophthalmology, University of Erlangen-Nürnberg, Erlangen, Germany.

DESIGN

Experimental study.

METHODS

Twenty-five porcine corneas were used for stromal flap or lamellar bed creation (stromal depth, 150 μm) and 15 rabbit corneas for lamellar bed creation near the endothelium. Ultraviolet femtosecond laser cutting-line morphology, gas formation, and keratocyte death rate were evaluated using light and electron microscopy and compared with a standard infrared (IR) femtosecond laser. Endothelial cell survival was examined after application of a laser cut near the endothelium.

RESULTS

Flaps created by the UV laser were lifted easily. Gas formation was reduced 4.2-fold compared with the IR laser (P = .001). The keratocyte death rate near the interface was almost doubled; however, the death zone was confined to a region within 38 μm ± 10 (SD) along the cutting line. Histologically and ultrastructurally, a distinct and continuous cutting line was not found after UV femtosecond laser application if flap lifting was omitted and standard energy parameters were used. Instead, a regular pattern of vertical striations, presumably representing self-focusing induced regions of optical tissue breakdown, were identified. Lamellar bed creation with standard energy parameters 50 μm from the endothelium rendered the endothelial cells intact and viable.

CONCLUSION

The new 345 nm femtosecond laser is a candidate for pending in vivo trials and future high-precision flap creation, intrastromal lenticule extraction, and ultrathin Descemet-stripping endothelial keratoplasty.

FINANCIAL DISCLOSURES

Mr. Klenke and Ms. Skerl were paid employees of Wavelight GmbH when the study was performed. Dr. Seiler is a scientific consultant to Wavelight GmbH. No other author has a financial or proprietary interest in any material or method mentioned.

Application of cold patch in relieving pain after transepithelial photorefractive keratectomy

Although photorefractive keratectomy often results in better corneal stability and fewer corneal flap complications than LASIK, pain remains a major drawback of the procedure. The authors compared the safety and efficacy of a postoperative cold patch versus intraoperative application of a chilled balanced salt solution on transepithelial photorefractive keratectomy-related postoperative pain.

BACKGROUND:

A return toward toward photorefractive keratectomy has occurred due to better corneal stability and fewer corneal flap complications; however, pain remains a major drawback of the procedure. Currently, clinical pain control measures focus on the administration of pain medications, which may delay corneal epithelial healing and has, occasionally, led to serious corneal toxicity.

OBJECTIVES:

To investigate the safety and efficacy of a cold patch on postoperative pain and other relevant consequences of transepithelial photorefractive keratectomy.

METHODS:

A prospective, randomized controlled study was conducted. Forty patients (80 eyes) scheduled to undergo transepithelial photorefractive keratectomy for myopia or myopic astigmatism were randomly and equally assigned to be treated with ice-cold balanced salt solution during surgery (wash group) or to wear a postoperative cold patch on the eye for 24 h. The main outcomes were pain score on a visual analogue scale, postoperative eyelid edema, conjunctival hyperemia, epithelial healing time, haze and postoperative best-corrected visual acuity.

RESULTS:

All patients completed the final tests. Demographic characteristics and pain scores during surgery were similar between the two groups. The mean postoperative pain scores of patients in the cold patch group at 8 h, 16 h and 24 h were significantly lower than those of patients in the wash group. Scores for postoperative eyelid edema and conjunctival hyperemia in the cold patch group were also lower than in the wash group. Patients in the cold patch group used fewer painkillers. Epithelial healing time, haze and early recovery of visual acuity were similar between the two groups. No eyelid frostbite was observed.

CONCLUSION:

Wearing a cold patch on the eye after transepithelial photorefractive keratectomy effectively relieved pain and inflammation, and reduced the use of painkillers without any side effects.

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.

When case report became case series: 45 cases of late traumatic flap complications after laser-assisted in situ keratomileusis and review of Chinese literature

OBJECTIVE

To report 45 cases of late traumatic flap complications after laser-assisted in situ keratomileusis (LASIK) and discuss the continually increasing number of cases in China.

METHODS

A multicentre retrospective survey of eye injuries was carried in 31 military hospitals from January 2006 to December 2011. Detailed information from the medical records of all 92 cases with a history of prior LASIK treatment were collected and summarised, with respect to visual acuity (VA), flap condition, treatment and final outcome. All Chinese publications relevant to late traumatic flap complications in Chinese patients were retrieved and summarised.

RESULTS

92 inpatients (92 eyes) underwent LASIK surgery; 45 of these had traumatic LASIK flap complications. Flap dislocation was the commonest and most needed surgical repair. VA after treatment was good and no statistically significant difference was observed when compared with the 47 cases without flap complications. 109 articles related to late traumatic flap complications after LASIK were retrieved from four Chinese document databases. There were 550 cases of late traumatic flap complications. From 2004, case reports became more common; 10 or more cases were reported in some case series. VA of most cases was good and there was no remarkable vision loss after treatment.

CONCLUSIONS

Late traumatic flap complications after LASIK have become more frequent in China, although the prognosis of most cases is good.

A microscopy study of the structural features of post-LASIK human corneas

Purpose

To study the structural features of human post-LASIK corneas.

Methods

A pair of post-mortem donor corneas, from a 55-year old patient who underwent uncomplicated LASIK surgery five years previously, were bisected and fixed in 4% paraformaldehyde. The right cornea and one half of the left cornea were processed for light microscopy and scanning electron microscopy. One half of the right cornea was also examined by transmission electron microscopy.

Results

The flap-bed interface could be easily detected several years after LASIK and, although the flap appeared to be in close association with the stromal bed, there was a noticeable absence of reconnection between adjacent severed lamellae. Tissue gaps were evident at the flap margin, which once free of cellular components revealed the presence of a few bridging fibres.

Conclusion

Examination of corneas five years after LASIK revealed evidence of primitive reparative scar development at the wound interface, but no reconnection of severed collagen lamellae. Such findings may explain the occurrence of flap dislocation following trauma in some patients months or years after surgery.

Fibrinogen, riboflavin, and UVA to immobilize a corneal flap--conditions for tissue adhesion

PURPOSE

Laser-assisted in situ keratomileus (LASIK) creates a permanent flap that remains non-attached to the underlying laser-modified stroma. This lack of permanent adhesion is a liability. To immobilize a corneal flap, a protocol using fibrinogen (FIB), riboflavin (RF), and ultraviolet (UVA) light (FIB+RF+UVA) was devised to re-adhere the flap to the stroma.

METHODS

A model flap was created using rabbit (Oryctolagus cuniculus) and shark (Squalus acanthias) corneas. Solutions containing FIB and RF were applied between corneal strips as glue. Experimental corneas were irradiated with long wavelength (365 nm) UVA. To quantify adhesive strength between corneal strips, the glue-tissue interface was subjected to a constant force while a digital force gauge recorded peak tension.

RESULTS

In the presence of FIB, substantive non-covalent interactions occurred between rabbit corneal strips. Adhesiveness was augmented if RF and UVA also were applied, suggesting formation of covalent bonds. Additionally, exposing both sides of rabbit corneas to UVA generated more adhesion than exposure from one side, suggesting that RF in the FIB solution catalyzes formation of covalent bonds at only the interface between stromal molecules and FIB closest to the UVA. In contrast, in the presence of FIB, shark corneal strips interacted non-covalently more substantively than those of rabbits, and adhesion was not augmented by applying RF+UVA, from either or both sides. Residual RF could be rinsed away within 1 hour.

CONCLUSIONS

Glue solution containing FIB and RF, together with UVA treatment, may aid immobilization of a corneal flap, potentially reducing risk of flap dislodgement.

Management of a traumatic flap dislocation seven years after LASIK

Seven years after uneventful laser in situ keratomileusis (LASIK), a 48-year-old woman presented one week after being hit with an iron cord with blurry vision, pain, and irritation. The injury resulted in traumatic flap dislocation, epithelial ingrowth, and macrostriae. Following epithelial removal, the flap was refloated and repositioned. Nine interrupted sutures were used to secure the flap. Three-weeks after surgery with no sutures remaining, the epithelial ingrowth and macrostriae had resolved with a visual acuity of 20/20.

Removal of epithelial ingrowth via central perforating wound tract 6 years post LASIK

BACKGROUND

The purpose was to report a case of a novel approach for the removal of central interface epithelial ingrowth caused by a perforating corneal injury 6 years after laser-assisted in situ keratomileusis (LASIK).

METHODS

Access to a large central area of epithelial ingrowth under a LASIK flap was achieved through the wound tract from a perforating corneal injury. Suturing of the central LASIK flap in a similar manner commonly carried out peripherally was then performed to prevent recurrent epithelial ingrowth.

RESULTS

The offending epithelial ingrowth was removed with no recurrence over a 1-year follow-up.

CONCLUSIONS

This is, to our knowledge, the first reported case of central epithelial ingrowth removal from a LASIK interface by a perforating injury wound tract.

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.

Timing of eyelid surgery in the setting of refractive surgery: preoperative and postoperative considerations

PURPOSE OF REVIEW

With any operation, the surgeon should be aware of predisposing factors that may lead to postoperative complications. Here we review the major factors due for consideration in both eyelid and refractive eye surgery, preoperatively and postoperatively, and consider the importance of timing to lessen the inherent risks of each procedure.

RECENT FINDINGS

Refractive surgery can affect corneal sensation by ablating the corneal nerves and can cause serious corneal complications if followed by eyelid surgery. Studies find that patients undergoing eyelid surgery have a change in astigmatic error of as much as 1.0 D during the first 3 postoperative months. The longest reported follow-up period of astigmatic changes in adult patients following eyelid ptosis surgery is 1 year and a considerable number of patients had a change in cylinder of up to 0.3 D postoperatively. Blepharoplastic surgery is also reported to cause astigmatic changes postoperatively, significantly more if entire fat pads are removed.

SUMMARY

To prevent corneal exposure, postrefractive eyelid surgery should be performed at least 6 months after lamellar ablative procedures and at least 3 months after surface ablative procedures. Refractive surgery revision may be necessary when astigmatic error occurs and should be carried out no earlier than 6 months postoperatively to allow for stabilization. Cosmetic blepharoplasty with fat pad debulking should be performed at least 6 months prior to refractive surgery to allow for any potential corneal astigmatic change to stabilize, for regained strength in the orbicularis, and for improved tear film distribution.