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Higher order aberrations after keratoplasty for keratoconus
Maria Letizia Salvetat1, Paolo Brusini, Emilio Pedrotti
1Department of Ophthalmology, S. Maria della Misercordia Hospital, Udine, Italy.
Summary
Deep anterior lamellar keratoplasty (DALK) offers better anterior corneal optical quality after keratoconus (KC) treatment compared to penetrating keratoplasty (PK) and automated lamellar therapeutic keratoplasty (ALTK). This study evaluated higher order aberrations (HOAs) to compare these corneal transplant methods.
Area of Science:
- Ophthalmology
- Corneal Surgery
- Optical Science
Background:
- Keratoconus (KC) is a progressive corneal ectasia requiring transplantation.
- Conventional penetrating keratoplasty (PK), deep anterior lamellar keratoplasty (DALK), and automated lamellar therapeutic keratoplasty (ALTK) are surgical options for KC.
- Understanding higher order aberrations (HOAs) is crucial for assessing visual quality after corneal transplantation.
Purpose of the Study:
- To compare HOAs of the anterior and posterior corneal surfaces after PK, DALK, and ALTK in patients with KC.
- To evaluate the impact of different corneal transplantation techniques on visual optics.
Main Methods:
- Retrospective, observational study of KC patients (n=40) and controls (n=38).
- Corneal HOAs assessed using a Scheimpflug camera in 4-mm and 6-mm zones post-surgery.
- Wavefront data analyzed using Zernike polynomials; third- and fourth-order HOAs quantified.
Main Results:
- DALK demonstrated significantly lower total anterior HOAs compared to ALTK and PK (p < 0.05).
- Posterior corneal HOAs were comparable across all surgical groups (p > 0.05).
- Specific aberrations like coma and trefoil varied between surgical techniques.
Conclusions:
- The anterior corneal surface exhibits superior optical quality following DALK compared to ALTK and PK.
- DALK may be a preferred method for preserving anterior corneal optical integrity in KC treatment.
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