Our purpose is to analyze the changes induced in the posterior corneal surface in patients implanted with intracorneal ring segments for treatment of keratoconus. Patients are assessed with corneal imaging device preoperatively and at 1, 3, 6 and 12 months postoperatively.

Procedure: Femtosecond laser assisted implantation of intracorneal ring segments in keratoconus patients Uncorrected visual acuity (UCVA), best corrected visual acuity (BCVA), refraction, keratometric (K) readings of the anterior and posterior surface, corneal asphericity (Q value) of the anterior and posterior surface, and anterior and posterior elevations are evaluated using a corneal imaging device preoperatively and at 1, 3, 6 and 12 months after surgery.

Inclusion Criteria

• Patients with keratoconus grade 1, 2 or 3 according to Amsler-Krumeich classification.
• Best corrected visual acuity (BCVA) ≤ 6/12.
• Mean front keratometric (K) readings ≤ 60 diopters (D).
• Corneal thickness ≥ 400 µm at the location of ICRS implantation.
• Clear central cornea

Exclusion Criteria

• Central corneal opacity.
• Previous corneal laser refractive surgery.
• Previous corneal collagen cross linking.
• Previous cataract surgery or phakic IOL implantation.
• History of herpetic keratitis.
• History of acute hydrops.
• Ocular comorbidities such as cataract, glaucoma or retinal disease.
• Systemic diseases affecting healing process such as autoimmune or connective tissue disease.