To compare systemic vs topical acyclovir therapy for the prevention of recurrence of herpetic keratitis following penetrating keratoplasty (PK).

A retrospective observational study.

Patients who underwent PK for herpetic eye disease (HED) and prophylactically received acyclovir therapy postoperatively, either systemically (26 eyes) or topically (29 eyes), were analyzed. The main parameters evaluated were recurrence of herpetic keratitis, graft rejection, visual acuity, and graft survival rate.

Mean average follow-up period was 24.7 ± 3.6 months and 23.5 ± 2.3 months in the systemic and topical group, respectively (P = 0.73). The average duration of prophylactic antiviral therapy in systemic group was 16.1 ± 4.8 months and in topical group was 15.1 ± 3.5 months (P = .59). Recurrence of herpetic keratitis was seen in 12% in the systemic group compared to 55% in the topical group (P < .001). More eyes in topical group 15 (52%) had rejection episodes than in the systemic group 5 (19%) (P < .001). A best-corrected visual acuity of ≥ 20/40 was achieved in 31% and 7% eyes in the systemic and topical group, respectively, at the end of two years (P = .002). The clear graft survival rate in the systemic and topical acyclovir receiving group was 96.2% vs 86.2% at 12 months, and 88.5% vs 65.5% at 24 months, respectively.

Systemic acyclovir is more effective than topical acyclovir in achieving better graft outcomes after PK for HED.