ABSTRACT
Francesca Rossi, Paolo Matteini, Fulvio Ratto Istituto di Fisica Applicata “Nello Carrara,” Consiglio Nazionale delle Ricerche, Sesto Fiorentino, Italy
Luca Menabuoni, Ivo Lenzetti Ospedale Misericordia e Dolce, Unita` Operativa Oculistica, Azienda USL 4, Prato, Italy
Roberto Pini Istituto di Fisica Applicata “Nello Carrara,” Consiglio Nazionale delle Ricerche, Sesto Fiorentino, Italy
30.1 Basic Principles of Femtosecond Laser Ablation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 800 30.2 Femtosecond Laser Preparation of Ocular Flaps . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 800 30.3 Low-Power Diode Laser Welding of Ocular Tissues . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 802 30.4 Combining Femtosecond Laser Cutting and Diode Laser Suturing . . . . . . . . . . . . . . . . . . . . . . . . 804 30.5 Conclusions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 807
Acknowledgment . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 808 References . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 809
In the last decade, laser welding of corneal tissue has been clinically performed in corneal transplant operations for suturing the transplanted corneal flap. The technique is based on the photothermal activation of the stromal tissue, previously stained with a proper chromophore (e.g., indocyanine green) in order to produce absorption of the radiation emitted by a low-power diode laser (at 810 nm) only in the stained tissue. The resulting temperature rise induces modifications in the stromal collagen, creating intramolecular bridges between the cut walls. The results are the sealing of the wound, with negligible thermal damage to the surroundings, and an improved healing process. Recently, this laser welding technique has been proposed to be used in combination with femtosecond laser intratissue cutting of corneal tissue: a flap of preset and constant thickness is sculptured both in the donor and in the recipient eye. The transplanted corneal button thus perfectly matches the recipient bed. The combination of femtosecond laser cutting and diode laser welding thus provides an innovative “all laser” surgery, in which conventional surgical tools, like blades and stitches, can be avoided and replaced by more precise and effective laser tools.
