Self-focusing and spherical aberrations in corneal tissue during photodisruption by femtosecond laser - ENSTA Paris - École nationale supérieure de techniques avancées Paris Accéder directement au contenu
Article Dans Une Revue Journal of Biomedical Optics Année : 2010

Self-focusing and spherical aberrations in corneal tissue during photodisruption by femtosecond laser

Résumé

The use of ultrashort pulse lasers is current in refractive surgery and has recently been extended to corneal grafting (keratoplasty). When performing keratoplasty, however, permanent degradation of the optical properties of the patient's cornea compromises the penetration depth of the laser and the quality of the incisions, therefore causing unwanted secondary effects. Additionally, corneal grafting needs considerably higher penetration depths than refractive surgery. Little data are available about the interaction processes of the femtosecond pulses in the volume of pathological corneas—i.e., in the presence of spherical aberrations and optical scattering. We investigate the influence of the focusing numerical aperture on the laser–tissue interaction. We point out that at low numerical apertures (NAs), tissue damage is produced below and above the focal region. We attribute this phenomenon to nonlinear self-focusing effects. On the other hand, at high NAs, spherical aberrations become significant when focusing at high depths for posterior surgeries, which also limit the cutting efficiency. As high NAs are advisable for reducing unwanted nonlinear effects and ensure accurate cutting, particular attention should be paid to aberration management when developing clinical femtosecond lasers.

Dates et versions

hal-00575127 , version 1 (09-03-2011)

Identifiants

Citer

Valeria Nuzzo, Karsten Plamann, Michèle Savoldelli, Jean-Marc Legeais. Self-focusing and spherical aberrations in corneal tissue during photodisruption by femtosecond laser. Journal of Biomedical Optics, 2010, 15 (3), pp.038003. ⟨10.1117/1.3455507⟩. ⟨hal-00575127⟩
104 Consultations
0 Téléchargements

Altmetric

Partager

Gmail Facebook X LinkedIn More