Changes in the ABCD Keratoconus Grade After Intracorneal Ring Segment Implantation

Area of Science:

• Ophthalmology
• Corneal Surgery
• Biomedical Engineering

Background:

• Keratoconus is a progressive corneal ectasia leading to visual impairment.
• Intracorneal ring segments (ICRS) are used to regularize the corneal shape and improve vision.
• The ABCD keratoconus staging system integrates multiple parameters to classify disease severity.

Purpose of the Study:

• To evaluate the efficacy of the ABCD keratoconus staging system in reflecting changes after ICRS implantation.
• To assess the impact of Keraring implantation on keratoconus progression using the ABCD system.

Main Methods:

• Fifty eyes of 50 keratoconus patients received Keraring implantation using femtosecond laser.
• Preoperative and 6-month postoperative assessments included visual acuity, refraction, and Pentacam HR Scheimpflug tomography.
• The ABCD keratoconus staging system parameters (corneal radii, thickness, corrected visual acuity) were analyzed.

Main Results:

• ICRS implantation led to significant flattening of anterior and posterior corneal radii.
• Distance corrected visual acuity (DCVA) improved significantly post-surgery.
• The ABCD staging changed from A2B3C2D1 preoperatively to A1B2C2D1 postoperatively, primarily due to changes in elements A and B.

Conclusions:

• The ABCD keratoconus staging system effectively illustrates structural and visual function changes after ICRS implantation.
• ICRS implantation demonstrates positive outcomes in keratoconus management, as reflected by the ABCD staging system.