Complications associated with anterior basement membrane dystrophy after laser in situ keratomileusis

Clinical outcomes of epithelial basement membrane dystrophy after keratorefractive lenticule extraction

PURPOSE

To determine the clinical outcomes of keratorefractive lenticule extraction (KLEx) in eyes with epithelial basement membrane dystrophy (EBMD) that developed after surgery.

SETTING

Onnuri Smile Eye Clinic, Seoul, South Korea.

DESIGN

Retrospective single-center study.

METHODS

This study reviewed the medical records of 26 eyes of 16 patients who exhibited signs of EBMD after KLEx. Postoperatively, corneal findings and visual outcomes were evaluated. Statistical analyses were also performed on eyes without corneal complications after KLEx.

RESULTS

Signs of EBMD were first observed within 1 week postoperatively in 22 eyes (84.6%): 6 eyes (23.1%) showed epithelial defects, 10 eyes (38.5%) showed subepithelial corneal opacity, 5 eyes (19.2%) showed diffuse lamellar keratitis, and 1 eye (3.9%) showed epithelial ingrowth. Symptoms such as pain, while corneal lesions were present, occurred in 21 eyes (80.8%). At 3 months postoperatively, 21 eyes (80.8%) showed no specific findings on slitlamp microscopy after medical treatment, 2 eyes (7.7%) showed subepithelial corneal opacity, 2 eyes (7.7%) showed corneal scar, and 1 eye (3.9%) showed epithelial ingrowth. Uncorrected distance visual acuity was 20/25 or better in 24 eyes (92.3%), and spherical equivalent was within ±1.0 D in 20 eyes (76.9%). The efficacy index of the EBMD group did not significantly differ from the control group, while the safety index was significantly lower.

CONCLUSIONS

Manifestations of EBMD can occur after KLEx and can affect clinical outcomes. Most cases showed favorable results with appropriate nonsurgical treatment; however, some cases had long-term complications such as corneal scarring.

Unusual visual impairment after enhancement refractive surgery

We reported a case of rapidly developed corneal epithelial in-growth (EI) deteriorating visual acuity (VA) within the initial postoperative day. A 37-year-old male presented with decreased VA for 2 years. He underwent LASIK surgery 13 years ago. After enhancement surgery, postoperative VA was much worse than preoperative best corrected visual acuity (BCVA) 20/20 and decreased rapidly. VA of OD was 20/40 on Day 1, and 20/70 on Day 5, OS 20/20 on Day 1, 20/25 on Day 10, and 20/50 on Day 13 postoperatively. Corneal topography and optical coherence tomography (OCT) showed distinctive features. The patient was diagnosed with corneal EI postoperatively. After scraping ectopic corneal epithelial cells, the cornea became transparent and VA improved. Despite its rarity, early postoperative EI can occur within 1 day after enhancement surgery and can progress rapidly. OCT and corneal topography provide distinctive manifestations aiding diagnosis.

A Literature Review of the Incidence, Management, and Prognosis of Corneal Epithelial-Related Complications After Laser-Assisted In Situ Keratomileusis (LASIK), Photorefractive Keratectomy (PRK), and Small Incision Lenticule Extraction (SMILE)

Our purpose is to provide a comprehensive investigation into the incidence, treatment modalities, and visual prognosis of epithelial-related complications in corneal refractive surgeries, including laser-assisted in situ keratomileusis (LASIK), photorefractive keratectomy (PRK), and small incision lenticule extraction (SMILE). A systematic search of multiple databases was conducted by two independent examiners using various search terms related to epithelial-related complications and corneal refractive surgeries. A total of 91 research articles were included, encompassing a sample size of 66,751 eyes across the three types of surgeries. The average incidence of epithelial-related complications varied across the different types of corneal refractive surgeries. LASIK had an average incidence of 4.9% for epithelial defects, while PRK and SMILE had lower rates of 3.3% and 3.9%, respectively. Our findings indicate that SMILE has a lower incidence of epithelial defects compared to LASIK, potentially due to the less invasive nature of lenticule incision in SMILE. Visual prognosis after epithelial complications (EC) is generally favorable, with various supportive care and surgical interventions leading to significant improvements in postoperative visual acuity and full recovery. Understanding the incidence rates and management approaches for epithelial-related complications can guide clinicians in enhancing patient safety, refining surgical techniques, and optimizing postoperative outcomes in corneal refractive surgeries.

Laser refractive surgery in corneal dystrophies

Twenty-eight case reports and case series published between 2000 and 2019 concerning laser refractive surgery in patients with corneal dystrophies, resulting in 173 eyes from 94 patients, were included in this systematic review. Best results were achieved in posterior corneal polymorphous and Cogan dystrophy. Unfavorable results were found in Avellino dystrophy and Fuchs endothelial corneal dystrophy (FECD). Photorefractive keratectomy was not indicated in Meesmann and Avellino dystrophy. Laser in situ keratomileusis was indicated in posterior polymorphous corneal dystrophy but not in FECD, Avellino, or Cogan dystrophy. Small-incision lenticule extraction and other dystrophies such as lattice, fleck, Lisch, or François did not achieve enough scientific evidence to report any recommendation.

Epithelial basement membrane dystrophy after femtosecond laser-assisted LASIK successfully treated with in vivo confocal microscopy-assisted photorefractive keratectomy

Photorefractive keratectomy (PRK) was performed to treat corneal epithelial basement membrane dystrophy (EBMD) found after femtosecond laser-assisted laser in situ keratomileusis (FS-LASIK) in a 29-year-old man with previous silent cornea. The patient was diagnosed with post-FS-LASIK EBMD by slitlamp examination and in vivo confocal microscopy (IVCM). Initial treatment with topical lubricants and alcohol soaking was unsuccessful, and the patient continued to have blurred vision and discomfort. The patient underwent a PRK procedure, and the symptoms resolved dramatically; residual refractive errors were also corrected. IVCM revealed a characteristic presentation of EBMD before PRK and normal corneal epithelium after treatment. Patients with asymptomatic EBMD might suffer from recurrent corneal erosions after FS-LASIK. Surface ablation including PRK might lead to successful treatment outcomes, and IVCM might provide helpful information before and after treatment.

Use of Collagen Binding Domains to Deliver Molecules to the Cornea

Purpose: The combined activity of the tear film and blinking is remarkably efficient at removal of foreign materials from the ocular surface. This has prevented the use of certain classes of drugs for the treatment of ocular surface problems. We propose that the use of peptide and protein domains that bind to moieties on the cornea could be used to deliver therapeutics by anchoring the drugs on the ocular surface long enough to provide therapeutic effects. Methods: In this study, we evaluated 4 different collagen binding domains fused to bacterial β-galactosidase for delivery of a reporter protein to collagen I and collagen IV-coated plates, rabbit corneas, and Herpes simplex virus (HSV-1) infected mouse corneas. Results: All 4 domains bound to collagen I and IV in vitro, whereas only a 10 amino acid (AA) sequence from bovine von Willebrand factor (vWF) and a 215 AA collagen binding domain from the bacterial protein ColH efficiently bound to abraded rabbit corneas. To test binding to corneas in a clinically relevant model, we assessed binding of the vWF collagen binding peptide fusions to HSV-1 infected mouse corneas. We observed that the vWF derived peptide mediated attachment to infected corneas, whereas the reporter protein without a collagen binding domain did not bind. Conclusions: Moving forward, the vWF collagen binding peptide could be used as an anchor to deliver therapeutics to prevent scarring and vision loss from damaged corneal surfaces due to disease and inflammation.

Bilateral corneal epithelial macrocysts following hyperopic laser in situ keratomileusis

A 27-year-old woman had microkeratome-assisted laser in situ keratomileusis (LASIK) for moderate bilateral hyperopia. The preoperative ophthalmologic examination was unremarkable except for minimal lissamine green staining bilaterally on the nasal conjunctiva. On the first postoperative day, the uncorrected distance visual acuity (UDVA) was 20/20 bilaterally and the corneas were clear. Four days later, the patient presented with mild blur in both eyes. Examination showed diffuse bilateral epithelial cysts encompassing the central 6.0 to 7.0 mm of the flaps with overlying diffuse lissamine green staining. The UDVA was 20/30 bilaterally. Aggressive lubrication was administered. The epithelial cysts coalesced into larger ones over subsequent visits and began regressing over several months, along with improvement in vision. At 6 months, the cysts had completely resolved, the corneas were clear, and the UDVA was 20/20.

LASIK and surface ablation in corneal dystrophies

Corneal dystrophies are a rare group of hereditary disorders, that are bilateral, non-inflammatory, and progressive. Clinically, they can be classified based on the anatomic layer of the cornea affected. Refractive surgery and phototherapeutic keratectomy (PTK) can be performed with caution in patients with certain corneal dystrophies, but should be avoided in others. For epithelial basement membrane dystrophy, photorefractive keratectomy (PRK) is the procedure of choice for treatment of refractive error, and PTK may be performed for the treatment of recurrent erosions or irregular astigmatism. PRK and laser-assisted in situ keratomileusis (LASIK) have been associated with exacerbation of combined granular-lattice corneal dystrophy. LASIK and PRK appear to be safe in mild forms of posterior polymorphous corneal dystrophy, whereas LASIK should be avoided in Fuchs dystrophy. The safety of refractive surgery and PTK in the remainder of epithelial, Bowman layer, and stromal dystrophies has yet to be established.

Techniques, indications and complications of corneal debridement

The cornea is the most exposed surface of the eye and, as such, is vulnerable to external trauma and the risk of infection. Many corneal diseases alter shape, surface, and transparency and thus result in reduced vision. The external position of the cornea, however, lends itself to diagnostic and therapeutic maneuvers that are commonly performed and readily done in the clinic. More sophisticated techniques require the use of complex equipment such as excimer and femtosecond laser. Complications that develop from poor healing and/or secondary infection are best avoided with appropriate technique, antisepsis, and modification of wound healing. We review corneal debridement in the management of corneal disease.

Laser refractive surgery in diabetic patients: a review of the literature

BACKGROUND

The purpose of this study was to evaluate the current recommendations regarding laser refractive surgery in patients with diabetes mellitus and to assess whether these patients make appropriate candidates for laser vision correction.

METHODS

A literature search was conducted to identify current research on the ocular complications of diabetes and original publications on laser refractive surgery in diabetic patients.

RESULTS

Diabetes was associated with several ocular complications. Initially the US Food and Drug Administration listed these complications as justification to advise against refractive surgery in patients with diabetes. However, recent studies on laser in situ keratomileusis in diabetic patients indicate that this procedure may be safe in diabetic patients with very well controlled systemic disease and no ocular manifestations.

CONCLUSION

Laser refractive surgery may be performed safely in a very selected group of patients with diabetes.

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.

Outcome of LASIK in fleck corneal dystrophy

PURPOSE

To report the outcome of laser in situ keratomileusis (LASIK) in a patient with Fleck corneal dystrophy.

METHODS

Case report and literature review.

RESULTS

A 48-year-old Taiwanese man presented in November 2005, 6 years after bilateral myopic LASIK. He complained of loss of uncorrected distance visual acuity that was worse in the left eye. The patient did not report glare, halos, or other visual aberrations. Preoperative best spectacle-corrected visual acuity (BSCVA) was 20/25 OU, with a manifest refraction of -14 D OU. In November 2005, uncorrected visual acuity (UCVA) was 20/40 OD and 20/50 OS, and BSCVA was 20/25 in each eye with a manifest refraction of -1.00 sphere OD and -1.75 -1.25 x 115 OS. Slit-lamp examination was remarkable for several subtle, small, gray corneal opacities present throughout the corneal stroma. Confocal microscopy revealed refractile bodies within swollen keratocytes and normal surrounding stromal mileu. The clinical and confocal appearance was consistent with Fleck corneal dystrophy.

CONCLUSION

In this patient with Fleck corneal dystrophy, corneal clarity and BSCVA were maintained 6 years after bilateral myopic LASIK, suggesting that LASIK does not stimulate visually significant exacerbation of Fleck corneal dystrophy.

Laser in situ keratomileusis in patients with diabetes

PURPOSE

To study the outcomes of laser in situ keratomileusis (LASIK) in patients with well-controlled diabetes mellitus.

SETTING

Gimbel Eye Centres, Calgary and Edmonton, Canada.

METHODS

The charts of all patients with diabetes who had LASIK surgery at the Gimbel Eye Centres were reviewed retrospectively. Uncorrected visual acuity (UCVA), best spectacle-corrected visual acuity (BSCVA), final refraction, and complications were assessed.

RESULTS

Twenty-four patients (16 men and 8 women) were identified. Mean patient age was 42 years (range 24 to 57 years). Seventeen patients had diabetes type II, and 7 had diabetes type I. Mean preoperative spherical equivalent (SE) was -4.88 +/- 2.13 diopters (D) (range +1.625 to -9.00 D). Median follow-up was 6 months (range 4 to 44 months). No eye lost BSCVA. Twenty-nine eyes (63%) achieved UCVA 20/25 or better, and 31 eyes (67%) were within +/-0.5 D of the intended refraction after the first LASIK surgery. Retreatment was required in 13 eyes (28.3%) because initial surgery was not adequate to correct the refractive error. At the last follow-up visit, 40 eyes (87%) achieved UCVA of 20/25 or better and 43 eyes (93.5%) were within +/-0.5 D of the intended refraction. Three eyes (6.5%) developed an epithelial defect after surgery, and secondary epithelial ingrowth developed in 2 of these eyes. No advancement of diabetic retinopathy was noticed in any eye at the end of the follow-up period.

CONCLUSIONS

Laser in situ keratomileusis surgery was safely performed in patients with well-controlled diabetes. Enhancement may often be required for optimal correction.

Severe corneal epithelial sloughing during laser in situ keratomileusis as a presenting sign for silent epithelial basement membrane dystrophy

PURPOSE

To report the occurrence of large intraoperative epithelial sloughing during laser in situ keratomileusis (LASIK) as a first diagnostic sign for silent epithelial basement membrane dystrophy (EBMD).

SETTING

Refractive Surgery and Cornea Unit, Alicante Institute of Ophthalmology, Alicante, Spain.

METHODS

In this retrospective case series, the medical records of all patients with large corneal epithelial sloughing/defects during LASIK from January 1995 to December 2004 were reviewed. All patients who presented normal corneas before LASIK and EBMD changes after LASIK were included in this study. The surgical procedures and postoperative course were recorded. The follow-up period was 12 months for all patients.

RESULTS

Eleven eyes of 6 patients were included. The mean age was 35 years +/- 6.1 (SD). Mean preoperative uncorrected visual acuity (UCVA) was 20/500 (0.04 +/- 0.02); 12 months after surgery, mean UCVA increased to 20/27 (0.74 +/- 0.21). There was a significant decrease in best spectacle-corrected visual acuity 1 month after surgery. One year postoperatively, 10 of 11 eyes (91%) were within +/-1.00 diopter of emmetropia. Postoperatively, clinical manifestations of EBMD were observed in all eyes and complications were common. In the early postoperative period, diffuse lamellar keratitis was observed in 6 of 11 eyes (54.5%) and flap microfolds were noted in 2 of 11 (18.2%). One year after surgery, epithelial ingrowth was present in 8 of 11 eyes (72.7%) and flap melting was noted in 4 of 11 (36.4%).

CONCLUSION

Occurrence of large intraoperative epithelium sloughing/defects during LASIK might be a diagnostic sign for subclinical EBMD. These patients are predisposed to multiple postoperative complications. Because of the high risk for epithelial sloughing in the second eye, LASIK should not be performed.