Corneal clarity measurements in patients with keratoconus undergoing either penetrating or deep anterior lamellar keratoplasty

Abstract

PurposeTo compare the corneal clarity measurement between penetrating keratoplasty (PK) and deep anterior lamellar keratoplasty (DALK) in patients with keratoconus, using densitometry software for the Oculus Pentacam.MethodsA retrospective comparative study was carried out at Manchester Royal Eye Hospital. Data were collected 12–18 months after corneal transplantation for keratoconus, including postoperative corneal densitometry, best corrected visual acuity (BCVA), central corneal thickness (CCT), and other relevant clinical details.ResultsAnalysis of 37 keratoconus eyes from 36 patients found there was a significantly higher corneal densitometry measurement after DALK than PK. This was predominantly in the posterior layer of the concentric zone 0–2 mm of the cornea (P=0.0004). A significant correlation was found between postoperative BCVA and corneal densitometry in DALK groups at full thickness (P=0.03). This correlation was seen in the central 0–2 mm (P=0.03) and posterior 0–2 mm (P=0.04) zones. In addition, within the DALK group, a correlation was found between central corneal thickness and densitometry at full thickness 2–6 mm (P=0.007), central 0–2 (P=0.04), central 2–6 mm (P=0.01), and at posterior 2–6 mm (P=0.01) zones.ConclusionThis study showed that corneal densitometry measurement differs depending on the type of corneal transplantation used to treat keratoconus patients. Densitometry may have an important role to play in the final BCVA achieved by patients undergoing corneal transplantation for keratoconus. Analysis of Oculus Pentacam images provides an objective evaluation to monitor the cornea status after the surgery.

Corneal aberrations, densitometry on scheimpflug imaging, and visual acuity after deep anterior lamellar keratoplasty

“…We found limited studies analyzing the corneal densitometry and its correlation with BSCVA. Alzahrani et al in 2017 25 compared DALK and PKP using corneal densitometry as a parameter measured by Oculus Pentacam and found significantly higher corneal densitometry after DALK compared to PKP. Also, postoperative BCVA significantly correlated with corneal densitometry in DALK.…”

Assessment of Corneal Densitometry in Big-Bubble Dissection Versus Manual Dissection Deep Anterior Lamellar Keratoplasty

“…This procedure conserves the host endothelium and decreases the risk of endothelial rejections. 1 However, the largest obstacle against adopting DALK is the challenges in achieving successful stromal dissection from DM. 2 The big-bubble technique is widely used to obtain the optimal depth DALK, which allows the exposure of the predescemetic layer or DM using air injection.…”