Femtosecond laser treatment of the crystalline lens: a 1-year study of possible cataractogenesis in minipigs

Ackermann, Roland; Kunert, Kathleen S.; Kammel, Robert; Bischoff, Sabine; Bühren, Stephanie C.; Schubert, Harald; Blum, Marcus; Nolte, Stefan

doi:10.1007/s00417-011-1772-z

Cited by 10 publications

(6 citation statements)

References 17 publications

(20 reference statements)

Supporting

Mentioning

Contrasting

Order By: Relevance

“…9,10 A similar strategy is applied in the concept of fs-laser presbyopia treatment, which aims to restore the elasticity of the lens by inducing laser disruptions in the hardened lens nucleus. [11][12][13] Moreover, fs-laser-induced cuts within the vitreous body may reduce vitreous traction and are therefore discussed as a preventive therapy for posterior vitreous detachment.…”

Section: Introductionmentioning

confidence: 99%

Enhancing precision in fs-laser material processing by simultaneous spatial and temporal focusing

et al. 2014

Self Cite

View full text Add to dashboard Cite

In recent years, femtosecond (fs)-lasers have evolved into a versatile tool for high precision micromachining of transparent materials because nonlinear absorption in the focus can result in refractive index modifications or material disruptions. However, when high pulse energies or low numerical apertures are required, nonlinear side effects such as self-focusing, filamentation or white light generation can decrease the modification quality. In this paper, we apply simultaneous spatial and temporal focusing (SSTF) to overcome these limitations. The main advantage of SSTF is that the ultrashort pulse is only formed at the focal plane, thereby confining the intensity distribution strongly to the focal volume and suppressing detrimental nonlinear side effects. Thus, we investigate the optical breakdown within a water cell by pump-probe shadowgraphy, comparing conventional focusing and SSTF under equivalent focusing conditions. The plasma formation is well confined for low pulse energies ,2 mJ, but higher pulse energies lead to the filamentation and break-up of the disruptions for conventional focusing, thereby decreasing the modification quality. In contrast, plasma induced by SSTF stays well confined to the focal plane, even for high pulse energies up to 8 mJ, preventing extended filaments, side branches or break-up of the disruptions. Furthermore, while conventional focusing leads to broadband supercontinuum generation, only marginal spectral broadening is observed using SSTF. These experimental findings are in excellent agreement with numerical simulations of the nonlinear pulse propagation and interaction processes. Therefore, SSTF appears to be a powerful tool to control the processing of transparent materials, e.g., for precise ophthalmic fs-surgery.

show abstract

Section: Introductionmentioning

confidence: 99%

Enhancing precision in fs-laser material processing by simultaneous spatial and temporal focusing

et al. 2014

Self Cite

View full text Add to dashboard Cite

show abstract

“…An animal study with rabbits reports that the laser pattern was still visible six months after treatment, though steadily fading [32]. In a 1-year follow-up with minipigs, the laser pattern turned out to be stable throughout the study [33]. Therefore, the 3 µm-pattern cannot be used due to bad contrast sensitivity (Fig.…”

Section: Discussionmentioning

confidence: 99%

Optical side-effects of fs-laser treatment in refractive surgery investigated by means of a model eye

Ackermann

Kammel

Merker

et al. 2013

Biomed. Opt. Express

Self Cite

View full text Add to dashboard Cite

Optical side-effects of fs-laser treatment in refractive surgery are investigated by means of a model eye. We show that rainbow glare is the predominant perturbation, which can be avoided by randomly distributing laser spots within the lens. For corneal applications such as fs-LASIK, even a regular grid with spot-to-spot distances of ~3 µm is sufficient to minimize rainbow glare perception. Contrast sensitivity is affected, when the lens is treated with large 3D-patterns.

show abstract

“…Fs‐laser treatment of the vitreous body within whole eyeballs was performed by suctioning the cornea to a contact glass (VisuMax treatment pack, size L, Carl Zeiss Meditec AG, Jena), which was connected to a custom‐made vacuum‐pump . In this experimental study, no feedback mechanism was available to determine the actual depth of the laser focus within the eyeball.…”

Section: Methodsmentioning

confidence: 99%

“…In contrast to ReLEx® or lens fragmentation, where the treated tissue is removed, fs‐laser treatment for presbyopia or vitreoretinal diseases would be applied to the closed eyeball. Concerning lenticular applications, animal studies have indeed shown that fs‐laser patterns within the crystalline lens are persistent . These persistent modifications appear as characteristic streaks in the vicinity of the focal plane and have been observed in all ocular media so far .…”

Section: Introductionmentioning

confidence: 91%

See 1 more Smart Citation

An in vitro study on focusing fs-laser pulses into ocular media for ophthalmic surgery

et al. 2013

Self Cite

View full text Add to dashboard Cite

show abstract

Femtosecond laser treatment of the crystalline lens: a 1-year study of possible cataractogenesis in minipigs

Abstract: Femtosecond laser treatment seems to be no trigger for cataract formation. Moreover, the long-term stability of the laser pattern makes it suitable for applications such as presbyopia treatment.

Cited by 10 publications

References 17 publications

Enhancing precision in fs-laser material processing by simultaneous spatial and temporal focusing

Enhancing precision in fs-laser material processing by simultaneous spatial and temporal focusing

Optical side-effects of fs-laser treatment in refractive surgery investigated by means of a model eye

An in vitro study on focusing fs-laser pulses into ocular media for ophthalmic surgery

Contact Info

Product

Resources

About