In vivo confocal microscopic investigation of the cornea after autologous implantation of lenticules obtained through small incision lenticule extraction for treatment of hyperopia

Abstract

Purpose: To investigate re-innervation in the implanted lenticule, as well as changes to the cornea, after correcting hyperopia with an autologous implantation of a lenticule obtained through small incision lenticule extraction (SMILE). Methods: This study retrospectively analysed re-innervation in the implanted lenticule, as well as microscopic morphological changes in the corneal architecture of the recipient cornea in five patients (with myopia in one eye and hyperopia in the contralateral eye) who received SMILE in the myopic eye and femtosecond laser in situ keratomileusis (FS-LASIK) combined with lenticule implantation in the contralateral hyperopic eye. Re-innervation in the implanted lenticule, as well as microscopic morphological changes in corneal architecture, were evaluated by in vivo confocal microscopy. Results: One patient was examined at postoperative week six, two were examined at postoperative month two, one was examined at postoperative month nine, and one was examined at postoperative month 12. Partial subbasal nerve fibre regeneration was detected in two patients (Case 4 who was examined at postoperative month nine and Case 5 who was examined at postoperative month 12). Regenerated and branched nerve fibres were detected in the implanted lenticule in Case 5 who was examined at postoperative month 12. Both the anterior and posterior interfaces showed an absence or decrease of keratocytes and the presence of small particles of various brightnesses. Keratocytes in the implanted lenticule presented abnormal morphology in size and shape after surgery in all treated eyes, but showed partial morphological recovery in two patients (Case 4 who was examined at postoperative month nine and Case 5 who was examined at postoperative month 12). Conclusions: These preliminary findings suggest that nerve fibres will regenerate into the implanted lenticule after autologous lenticule implantation. Keratocytes in lenticules demonstrated a gradual return to a normal morphology.

Incisional surface quality of electron-beam irradiated cornea-extracted lenticule for stromal keratophakia: high nJ-energy vs. low nJ-energy femtosecond laser

“…Although the femtosecond laser-created photodisruptive process purportedly reduces collateral damage to the corneal stroma, the heat and mechanical effects could create collagen fibrillar derangements at the incisional surface (34). The disturbances presented as increased reflectivity under in vivo confocal microscopy in previous studies and were found to attenuate over time (39,40). The present study is the first to quantify collagen morphology derangement through multiphoton microscopy in the context of examining incisional surfaces created by femtosecond lasers.…”

“…10.3389/fmed.2023.1289528 (10,(39)(40)(41). The interface between the lenticule and host stroma may heal and become unnoticeable given sufficient time (14,39,40,42).…”

“…10.3389/fmed.2023.1289528 (10,(39)(40)(41). The interface between the lenticule and host stroma may heal and become unnoticeable given sufficient time (14,39,40,42). The minimally invasive nature of the lenticule reimplantation procedure does not extensively disrupt the ocular surface, ensuring the minimal involvement of ocular surface antigen-presenting cells (43), hence there is minimal effect on stromal remodeling and tissue bio-integration in the long term.…”

Carbodiimide crosslinked decellularized lenticules as a drug carrier for sustained antibacterial eye treatments

“…With the extensive development of small incision lenticule extraction (SMILE) surgery, the source of SMILE-derived lenticules is abundant and they have become easier to obtain [2][3][4]. A number of studies have preliminarily confirmed the efficacy and safety of SMILE-derived lenticules as a patch graft for the treatment of corneal perforation [5][6][7], hyperopia [8][9][10][11] and keratoconus [12][13][14]. In addition, SMILE-derived lenticules can be used as a good scaffold material to culture corneal cells [15] and construct corneal stroma [16].…”

“…At present, freshly obtained corneal stromal lenticules are primarily used in research studies [11,17,18], but investigations have found that immune rejection after keratoplasty is related to the cellular components of corneal allografts [19]. However, the immunogenicity of SMILE-derived lenticules can be reduced by removing some cellular components [20][21][22].Studies have shown that a high concentration of sodium chloride solution combined with nuclease can effectively remove the DNA components of cells in corneal stroma and maintain the structure of the collagen fibers [20].…”