Intrastromal refractive surgery with ultrashort laser pulses: in vivo study on the rabbit eye

Abstract

The use of the fs-laser offers new possibilities in preparation of corneal flaps, possibly providing advantages over conventional microkeratomes. Furthermore, the fs-laser has the potential to create intrastromal refractive lenticules for complete refractive procedures (ILK).

Anterior chamber gas bubbles after corneal flap creation with a femtosecond laser

“…In media with high aqueous saturation, such as the cornea, a vapor-filled bubble develops at the breakdown region without interfering with surface cell layers. 1,2,5 Due to the photodissociation of involved water, the bubble contains hydrogen. Femtosecond laser-induced optical breakdown requires very low energy and produces virtually no thermal damage or shockwave transmission to surrounding tissue.…”

“…If 2 successive laser pulses are placed too close to each other, the produced bubbles merge, leading to large intrastromal bubbles that will deflect following laser pulses, resulting in remaining tissue bridges. 5 To overcome this problem, the pulses of very low energy threshold are delivered in a raster pattern, resulting in microcavitation bubbles and allowing nearly contiguous placement of laser pulses without almost collateral shockwave effects.…”

“…[1][2][3][4][5][6] These reported advantages include the creation of more predictable flap dimensions, the use of low vacuum during suction, and the theoretical elimination of intraoperative flap complications such as incomplete flap, buttonhole perforation, and unpredictable thickness. [2][3][4]6 In essence, the femtosecond laser is focused on a predetermined depth within the corneal stroma, delivering pulses of light in a raster pattern, creating focused cavitation spots within the stroma that will expand and result in a resection plane.…”

Confocal assessment of the corneal response to intracorneal lens insertion and laser in situ keratomileusis with flap creation using IntraLase

“…[14][15][16][17][18][19][20][21][22] Because the procedure is relatively new, the corneal wound-healing response to LASIK with IntraLase has not been well documented. 23 Similarly, although 2-dimensional confocal images have been used to qualitatively assess the effects of hydrogel ICLs in humans, quantitative 3-dimensional analysis has not been performed. 9,24 In this study, we used quantitative 3-dimensional confocal microscopy to assess and compare the responses of the cornea to LASIK with IntraLase and ICL implantation following IntraLase flap creation.…”

Femtosecond laser in ophthalmology – A short overview of current applications

“…In an early fs study performed by Heisterkamp et al [13], investigators created the fs flap cut at an angle of 60 • to avoid difficulties with the opening of the flap. They found no significant wound healing reaction inside the corneal stroma and no proliferation of epithelial cells.…”