Corneal Epithelial Ingrowth Research Articles

Corneal epithelial ingrowth after small incision lenticule extraction surgery: Insights from a case series and mechanistic studies

AbstractCorneal epithelial ingrowth (EI) is a rare but significant complication following Small Incision Lenticule Extraction (SMILE) surgery. During the procedure, the opaque bubble layer (OBL) formation may create microchannels that disrupt Bowman's layer, providing a pathway for epithelial cells to migrate into the corneal stroma. In this study, we investigated the mechanisms behind EI development and proposed preventive strategies. We analyzed four cases of EI post‐SMILE surgery, utilizing anterior segment optical coherence tomography (AS‐OCT) and corneal tomography for diagnosis. Preventive measures, including careful anesthetic application and precise suction cone positioning, were employed to minimize OBL formation. Here, we show that subflap debris removal surgery led to significant clinical improvement, with no EI recurrence observed. Our findings suggest that the microchannels created by OBL during surgery may play a crucial role in EI development, challenging previous assumptions that EI is primarily due to trauma at the flap edges. This underscores the importance of precise surgical technique and effective postoperative management. Further research, including clinical studies and advanced imaging, is needed to confirm this proposed mechanism and improve outcomes in refractive surgery. The study highlights the necessity for ongoing advancements in surgical protocols and technology to prevent and manage EI effectively.

Corneal epithelial ingrowth after perforating corneal injury: a case report

BackgroundEpithelial ingrowth is a rare complication after ocular perforation and can become manifest many years after the primary trauma.Case presentationA 49-year-old patient presented with a positive Seidel test of unclear origin at her left eye, as well as a sharply defined anterior-stromal corneal scar at both eyes. Prior operations included a bilateral laser-assisted blepharoplasty 3 months earlier. The patient indicated to have been on holiday to France 5 months earlier, during an ongoing oak processionary moth caterpillars infestation.The examination using confocal microscopy confirmed a corneal perforation at the left eye and revealed corneal epithelial ingrowth capped with scarred stroma in both eyes. We performed a penetrating keratoplasty at the left eye. The scarred and perforated host cornea was divided into 4 pieces for further investigation: microbiology (negative), virology (negative), histology and transmission electron microscopy (TEM). Histology revealed differently structured epithelium, centrally inverted into the stroma through defects in Bowman’s layer. TEM revealed full thickness corneal perforation with an epithelial plug extending to the lower third of the cornea, but without evidence of epithelial cell migration into the anterior chamber.Our differential diagnosis of the unclear positive Seidel test with epithelial ingrowth was as follows: (1) corneal perforation by hairs of the oak processionary moth caterpillar, although no hairs could be found histologically; (2) corneal perforation during laser-assisted blepharoplasty, which may be supported by the presence of pigmented cells on the posterior surface of Descemet´s membrane, pointing to a possible iris injury.ConclusionConsequently, we highlighted that contact lenses can be useful, safe and inexpensive protective devices in upper eyelid procedures to protect the cornea against mechanical iatrogenic trauma.

Outcomes of Flap Lift Laser In Situ Keratomileusis Enhancements in a Large Patient Population: Does Application of a Bandage Contact Lens Affect Incidence of Epithelial Ingrowth?

To compare the incidence of corneal epithelial ingrowth (EIG) and the visual outcomes of enhancement with laser in situ keratomileusis (LASIK) by flap lift when a bandage soft contact lens (CL) was fitted after the procedure and when it was not. This is a multicenter, retrospective, interventional case series in which all patients who underwent LASIK enhancement from January 2005 to January 2015 were included consecutively. Patients were grouped depending on whether a bandage CL was fitted after re-treatment by flap lift (group 1) or not (group 2). A total of 16,702 eyes from 12,485 patients were included. There were statistically significant differences between the groups regarding corrected distance visual acuity (better in group 1) and safety index (better in group 2) although these were not clinically relevant. The incidence of EIG was 0.58% in group 1 and 0.55% in group 2 although, again, the difference was not statistically different. We found no relevant differences in LASIK enhancement between patients who received a bandage CL and those who did not regarding the incidence of EIG and visual outcomes.

Treatment for traumatic corneal flap dislocation after laser in situ keratomileusis

Objective To observe the effection of reposition for corneal flap dislocation after LASIK due to trauma. Methods All the 12 military patients( 12 eyes) with traumatic cornea flap dislocation after LASIK were treated with relocating,and wearing soft contact lens. The vision, cornea flap and the symptoms were observed. Results The vision increased to 0.8-1.0 in 9 cases; 0. 6 in 2 cases; 0. 3 in one case.The corneal flaps were relocated properly without refolding, redislocation, corneal epithelial ingrowth or cornea solution,The symptom of ache,photophobia and lacrimation were improved. Conclusion The reposition of corneal flaps showing to be an efftective therapy for patients with corneal flap dislocation after LASIK on improving vision and corneal flap recovering. Key words: LASIK; corneal flap dislocation; trauma; treatment

Phototherapeutic keratectomy for the treatment of corneal epithelial ingrowth after laser in situ keratomileusis

目的 探讨激光治疗性角膜切削术(PTK)治疗LASIK术后角膜上皮内生的方法和效果,方法 LASIK术后较严重的角膜瓣下角膜上皮内生4例(4眼),进行内生的上皮刮除和PTK治疗后戴接触镜3～5天,随访10～24个月,结果 4例均治愈,随访期内无复发,视力均恢复至术前最佳矫正视力.眼部刺激症状、眩光消失.结论 LASIK术后瓣下角膜上皮内生,进行角膜瓣后面和角膜床表面的角膜上皮刮除及PTK术,术后戴角膜接触镜,是治疗LASIK术后瓣下角膜上皮内生的有效方法。

Laser in situ keratomileusis induced corneal perforation and recurrent corneal epithelial ingrowth

We report a rare complication of recurrent corneal epithelial cell ingrowth after corneal perforation induced by laser in situ keratomileusis. A corneal flap was made uneventfully with an automatic SCMD microkeratome (Howard Instruments, Inc.). During laser ablation, instead of random burning over the stromal bed, repeated ablation at a single location occurred because of a machine malfunction, resulting in corneal perforation. The flap was replaced and sutured to prevent leakage of aqueous humor. As the cornea healed, the patient's vision was compromised by scar formation, high irregular astigmatism, and epithelial ingrowth. The flap was reopened, and the epithelial cells were removed by thoroughly scraping the flap and stromal bed. However, corneal epithelial ingrowth recurred within a week. The recurrent and progressive epithelial ingrowth further decreased vision, and penetrating keratoplasty was recommended.

Comparison of wound healing after photorefractive keratectomy and laser in situ keratomileusis in rabbits

Purpose To evaluate and compare the corneal wound-healing process after photorefractive keratectomy (PRK) and laser in situ keratomileusis (LASIK). Setting Kangnam St. Mary’s Hospital, Seoul, Korea. Methods Two surgical procedures, PRK with the VISX Star excimer laser and LASIK with a MicroTech microkeratome, were performed in 24 rabbit eyes. In the PRK group (n=12 eyes), the rabbit cornea was treated with a 20 μm ablation. In the LASIK group (n=12 eyes), a 20 μm laser ablation was performed after a 150 μm thick hinged corneal flap had been made. During both procedures, dichlorotriazinyl aminofluorescien (DTAF) dye was applied to the ablated stromal bed; in the LASIK group, the stromal side of the corneal flap was also stained with DTAF to differentiate regenerated collagen from normal stromal tissue. Corneal wound healing was evaluated postoperatively at 1, 4, 8, and 12 weeks using light, electron, and fluorescence microscopy. The amount of regenerated stromal tissue and the number of keratocytes were analyzed by an image-analysis system. Results In the PRK group, epithelial migration and regeneration were observed in the ablated area without any stromal regeneration 1 week postoperatively. However, newly regenerated, irregularly arranged stromal collagen, with epithelial hyperplasia in the ablated area, was observed 4 to 12 weeks postoperatively by light and fluorescence microscopy. The number of keratocytes in the surgical area was also increased. In ultrastructural observation using an electron microscope, the shape of keratocytes in the ablated area was changed, and the number of rough and smooth endoplasmic reticuli, ribosomes, mitochondria, and electron-dense vesicles in the cytoplasm were increased, suggesting that the cells were activated. In the LASIK group, there was no observed regenerated collagen between the corneal flap and the ablated stromal bed except in the wound margin. Lamellated, parallel collagen fibers in the cornealstroma were not disturbed. However, in the wound margin, corneal epithelial ingrowth between the flap and the stromal bed was observed, as was some regenerated stromal tissue. The amount of regenerated stromal tissue and the number of keratocytes in the wound area were statistically smaller than those in the PRK group ( P < .05). Observation by electron microscopy showed no activated keratocytes, unlike in the PRK group. The collagen fibers in the wound area were parallel. Conclusion Stromal wound healing in the LASIK group was minimal compared with that in the PRK group, except in the wound margin. These results may support the clinical findings of less corneal haze in the human cornea after LASIK.