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Updated: Jan 6, 2026

Full-Field Optical Coherence Microscopy for Histology-Like Analysis of Stromal Features in Corneal Grafts
Published on: October 21, 2022
Outcomes of Repeat Anterior Lamellar Keratoplasty
Jyh Haur Woo1,2,3,4, Yar Li Tan1,2,3,4, Hla Myint Htoon2,3,4
1Singapore National Eye Centre, Singapore.
Purpose:
To describe the outcomes and complications of repeat anterior lamellar keratoplasty (ALK) after a failed primary ALK.
Methods:
This was a retrospective case series. Twenty-three eyes of 22 patients who underwent repeat ALK for optical indications from January 1, 1991, to December 31, 2017, were included. Clinical data were recorded from the Singapore Corneal Transplant Study database. Outcome measures were graft survival, best-corrected visual acuity (BCVA), and complications.
Results:
Of the 780 cases of ALK performed for optical indications during the study period, 23 cases (2.9%) underwent repeat ALK. Primary ALK comprised of 16 deep ALK and 7 automated lamellar therapeutic keratoplasty cases. After repeat ALK, 21 eyes had further dissection down to the descemetic or predescemetic plane, whereas 2 eyes had graft exchange for failed automated lamellar therapeutic keratoplasty. The graft survival of repeat ALK was 93.2%, 86.1%, and 78.3% at 1, 3, and 5 years, respectively. There were 4 cases of graft failure with a mean time to failure of 2.0 ± 1.7 years. After the repeat ALK procedure, 63.6% and 66.7% of eyes achieved a BCVA of LogMAR +0.3 (20/40) or better at 1 and 2 years, respectively. Five eyes (17.4%) had an intraoperative microperforation.
Conclusions:
In the case of a failed ALK graft for a range of optical indications, a repeat ALK procedure offers a viable and safe surgical option with good long-term graft survival and visual outcomes, while avoiding the various disadvantages of performing penetrating keratoplasty, especially the risk of allograft endothelial rejection.

