Long-term outcomes of hemi-automated lamellar keratoplasty

To describe long-term outcomes of hemi-automated lamellar keratoplasty (HALK).

HALK is a hybrid anterior lamellar keratoplasty technique for corneas with anterior to mid-stromal scars and topographical irregularities.

Prospective interventional case series.

Thirty-five eyes of 35 consecutive patients undergoing HALK at a single tertiary referral centre from 2007 to 2016.

Patients were followed up for a mean period of 61.4 ± 29.2 months.

Uncorrected visual acuity (UCVA), best spectacle-corrected visual acuity (BSCVA), spherical equivalent (SE) and cylinder, endothelial cell density (ECD), central corneal thickness (CCT), graft survival and complications were analysed.

The most common indications for HALK were scars because of contact lens associated infectious keratitis (29%), unknown origin (26%) or corneal dystrophies (14%). Five patients had a previous keratoplasty (n = 4; deep anterior lamellar keratoplasty, n = 1). Two HALKs failed at 22 and 32 months follow-up. No graft rejections occurred. UCVA improved from 0.91 ± 0.31 to 0.58 ± 0.35 and BSCVA from 0.66 ± 0.30 to 0.21 ± 0.20 logMAR (P < 0.001) at the last follow-up. Astigmatism (P = 0.2), SE (P = 0.8) and ECD (P = 0.4) did not change significantly during follow-up. CCT increased from 490 to 560 μm (P = 0.004). Kaplan-Meier estimated survival for all HALK cases was 90.6 (95% confidence interval 82.6-98.5) months with a survival probability of 96% at 12 months and 92% at 3, 5 and 7 years of follow-up.

HALK provides excellent graft survival in primary cases and in patients with prior keratoplasty as well as significant improvement in visual acuity with low complication rates.