Corneal Densitometry After Dalk In Keratoconus

To evaluate longitudinal changes in corneal densitometry CD , best-corrected visual acuity (BCVA), and anterior chamber depth (ACD) following deep anterior lamellar keratoplasty (DALK) in patients with keratoconus using Pentacam imaging.

Department of Ophthalmology, İstanbul Faculty of Medicine, İstanbul University, İstanbul Türkiye.

This retrospective study included 20 eyes of 19 keratoconus patients who underwent deep anterior lamellar keratoplasty. Clinical data were reviewed over a follow-up period of 2 to 24 months. Corneal densitometry values and anterior chamber depth were assessed preoperatively, at the early postoperative period (2 months), and at the late postoperative period (24 months) using Pentacam AXL© (Oculus, Germany). Corneal densitometry was obtained objectively from Scheimpflug imaging across different corneal layers and annular zones. Best-corrected visual acuity was evaluated at all time points.

BCVA improved significantly over time(p < 0.001). Keratometric values (K1, K2, and Kmax) and ACD showed a significant postoperative reduction (p < 0.001). Preoperative and early postoperative CD values were evaluated; In the 0–2 mm zone, anterior CD 27.54±20.52 GSU and 22.74±10.11 GSU, respectively (p = 0.940). Similarly, in the 6–10 mm zone, anterior, posterior values significantly increased from 15.06±6.79, 8.75±1.56 GSU to 25.16±12.01, 9.95±2.01 GSU, respectively (all p < 0.001).In the 2–6 mm zone, central CD values were 12.18±6.26 GSU preoperatively and 15.96±9.96 GSU late postoperatively (p = 0.020).

DALK provides significant visual improvement and favorable changes in anterior segment parameters in patients with keratoconus. Pentacam-based corneal densitometry offers an objective and sensitive method for assessing postoperative changes in corneal transparency. The significant reduction in densitometry values observed in the early postoperative period (2 months), particularly in the central 0–2 mm zone, followed by stabilization at 24 months, suggests that corneal clarity improvement occurs predominantly in the central region and early postoperative phase. These findings support the clinical value of corneal densitometry for long-term postoperative monitoring and outcome assessment after lamellar keratoplasty.