Impact of Residual Stromal Thickness on the Outcomes of Manual Deep Anterior Lamellar Keratoplasty
Andrea Taloni, Costanza Rossi, Giuseppe Alessio, Maria A. Romeo, Luca Bifezzi, Massimiliano Borselli, Alessandra Mancini, Raffaella Gioia, Adriano Carnevali, Vincenzo Scorcia, Andrea Lucisano, Giovanna Carnovale-ScalzoPurpose:
To analyze how postoperative outcomes of manual deep anterior lamellar keratoplasty (mDALK) in eyes affected by keratoconus are influenced by the residual stromal thickness (RST) of the recipient.
Methods:
Retrospective interventional case series. Patients underwent DALK between 2011 and 2025 at “Magna Graecia” University of Catanzaro, Italy. Big-bubble DALK was the favorite stromal dissection technique, whereas mDALK was reserved as backup strategy. Best spectacle-corrected visual acuity (BSCVA) and tomographic parameters were evaluated preoperatively (T0) and postoperatively after complete suture removal (1 year, T2). RST was assessed 1 month postoperatively (T1) using the CASIA SS-1000 anterior-segment optical coherence tomography (Tomey, Nagoya, Japan). Measurements were performed at the center of the cornea and at 12 paracentral points along 6 different meridians equally spaced at 30 degrees.
Results:
In total, 288 eyes underwent DALK. Of these, 234 (81.3%) underwent successful pneumatic or viscoelastic dissection, whereas 54 (18.7%) required mDALK. In this subgroup, a significant correlation was found between postoperative BSCVA and central RST [56.17 ± 15.43 μm (95% confidence interval: 52.06–60.29); ρ = 0.397,
Conclusions:
Central RST presented a low-moderate yet significant correlation with postoperative BSCVA at 1 year. Corneal surgeons should aim to minimize RST compatibly with a safe stromal dissection.