Ex Vivo Histological Analysis of Corneas with Manually Implanted Intracorneal Stromal Ring Segments

Backgrond: Intracorneal ring segments (ICRSs) are utilized to correct refractive changes impacting visual acuity, commonly implanted via femtosecond laser but can also inserted manually. Corneal deposits alongside the ICRS channels are seen commonly. Methods: This study explores the histological characteristics of corneal deposits following manual ICRS implantation, comparing them to previously published articles describing femtosecond laser-assisted cases. Results: This is a retrospective analysis of three cases involving manual ICRS implantation, accumulation of whitish deposits and later explanation of the corneas due to penetrating keratoplasty (PKP). Patient demographics, ocular history, and surgical details were collected. Histological analysis employed Hematoxylin and Eosin (H&E) and Masson's trichrome staining. Whitish deposits along ICRS tracts were observed in all cases, with minimal fibroblastic transformation of keratocytes adjacent to the segments. Comparing these cases of manual to femtosecond laser-assisted ICRS implantation, in most cases, similar deposits were identified, indicating the deposits' association with the stromal tissue reaction to the ring segment and not to the surgical technique. Conclusions: This study contributes insights into the histopathology of manually implanted ICRS, emphasizing the shared nature of deposits in both insertion methods. The findings highlight the link between deposits and the stromal tissue reaction to the ring segment, irrespective of the insertion technique.