Therapeutic corneal transplantation in acanthamoeba keratitis. Penetrating versus lamellar keratoplasty

Purpose: The purpose of this article was to compare clinical outcomes between therapeutic penetrating keratoplasty (TPK), therapeutic deep anterior lamellar keratoplasty (TDALK), and optical penetrating keratoplasty (OPK) in Acanthamoeba keratitis. Methods: A literature search was conducted in online libraries from 1980 to 2021. The primary end points were best-corrected visual acuity (VA), graft survival, and infection recurrence. In addition, we enrolled 35 consecutive patients with AK from our practice evaluating best-corrected VA and high-order aberrations. Results: A total of 359 AK eyes from 33 published studies were retrieved from 175 publications screened. One hundred sixty-five eyes (73%) that underwent TPK and 39 eyes (84%) treated with TDALK had a clear graft at the last follow-up visit. Only the patients treated with OPK had 82 clear grafts (94%) during the follow-up period. Forty-seven (21%) of TPK patients reached VA ≥20/30, compared with 11 (25%) of TDALK patients and 35 (40%) of OPK patients. Acanthamoeba infection recurrence occurred in 38 eyes (16.8%) that underwent TPK, 9 (19%) that underwent TDALK, and 8 (9.5%) that underwent OPK. In our series, best-corrected visual acuity in nonsurgically treated patients was 1 ± 0.50 logMAR compared with 0 logMAR of surgically treated patients. High-order aberrations were significantly lower in surgically treated eyes after AK resolution, particularly in TDALK when compared with TPK patients. Best-corrected visual acuity was better in TDALK patients compared with TPK patients. Conclusions: After AK resolution by 6 to 12 months of medical treatment, OPK seems to be the best surgical choice in patients with AK. If AK could not be eradicated by medical therapy, TDALK may be chosen in the early disease stage and TPK in later stages.