Scheimpflug Corneal Densitometry Changes After the Intrastromal Corneal Ring Segment Implantation

Area of Science:

• Ophthalmology
• Corneal Surgery
• Biomedical Optics

Background:

• Keratoconus is a progressive thinning disorder of the cornea.
• Intrastromal corneal ring segments (ICRS) are used to improve visual acuity in keratoconus patients.
• Corneal densitometry measures light scattering within the cornea, providing insights into tissue structure.

Purpose of the Study:

• To evaluate changes in corneal backward scattering using Scheimpflug tomography (densitometry) 6 months after Keraring implantation for keratoconus.
• To correlate these densitometry changes with clinical outcomes.

Main Methods:

• Scheimpflug tomography (Pentacam HR) was used to measure corneal densitometry in grayscale units (GSUs).
• Densitometry was assessed in concentric annuluses (0-2, 2-6, 6-10, 10-12 mm) and at different depths (anterior, middle, posterior).
• Standard ophthalmic examinations were performed concurrently.

Main Results:

• A significant increase in mean corneal densitometry was observed across all corneal layers (P < 0.05), except the peripheral 10-12 mm annulus.
• The most substantial increase in scattering occurred in the 2-6 mm annulus of the anterior corneal layer (5.72 ± 3.70 GSU).
• Densitometry changes correlated significantly with alterations in average keratometry and Q-values in the 2-6 mm annulus.

Conclusions:

• Keraring implantation leads to a significant increase in corneal backward scattering, primarily in the anterior 2-6 mm annulus.
• The observed scattering is linked to the placement of the intrastromal ring segments.
• Further research is required to fully understand the clinical implications of these findings.