• The output is highly collimated laser beam about 1 mm to less than 1cm. It is a flapless procedure in which an intrastromal lenticule is created between two photodisruption planes and removed mechanically from an arcuate side cut of 3 to 4 mm . Optometry. With surface ablation procedures, such preparation consists of epithelial removal to expose the Bowman layer. Two-photon microscopy-guided femtosecond-laser photoablation of avian ... Photodynamic Lasers 40. . The LIOB generates a high-intensity electrical field. TYPESOFLASER 1- Helium neon laser was the first laser system to be used in clinical and research applications. Corneal response to femtosecond laser photodisruption in the rabbit It has been hypothesized that the XeCl laser . Soft tissue photo-thermal ablation (or photovaporolysis) is a process of vaporization of intra- and extra-cellular water. Retinal Laser Photocoagulation - Medical Journal of ... - FlipHTML5 3d), demonstrating our ability to resulted in venous pooling and rapid cardiac remodeling) and control and optimize the insult that is produced. (nanoJoule vs microJoule range), the total energy delivered to the It is a flapless procedure in which an intrastromal lenticule is created between two photodisruption planes and removed mechanically from an arcuate side cut of 3 to 4 mm . The type of laser- tissue interaction depends on the power density (W/cm2) and exposure time (s) (8). Tissue is heated until destroyed 2. A femtosecond (10-15 seconds) is one quadrillionth, or one millionth of one billionth of a second. Irv Arons' Journal: March 2011 - Blogger Because power is a function of energy per unit time, shorter pulse times further decrease energy output for a given effect [10]. Tammy Pifer Than, MS, OD, FAAO UAB School of Optometry tthan@uab.edu. Fundamentals of light-cell-polymer interactions in photo-cross-linking ... Refractive Surgery: Comparison of Femtosecond Lasers 1. Argon laser - pulsed) 3. An excimer laser, for example, generates photons at a wavelength of 193 nm; these photons are absorbed by and break the covalent bonds in corneal collagen, thereby vaporizing the collagen molecules. Photoablation Photodisruption Photocoagulation . Letters, review articles, animal or laboratory studies, and conference . A shorter pulse (200-500 fs) needs lower energy to achieve the threshold of photodisruption than a longer pulse (500-1300 fs). The results of excimer laser photoablation to correct astigmatism are usually accurate, but is not as good as with myopic treatments. Energy is concentrated in time and space to create . Plasma-induced ablation and photodisruption occur as a consequence of exposing the biological material to a power density above 1011 W/cm 2. PDF Enhancement of Cortical Bone Ablation Using Ultrafast Pulsed Lasers Shortest Exposure + Highest Intensity = PLASMA INDUCED ABLATION Photochemical P. S. Photodisruption and photoablation have joined photocoagulation as established medical laser procedures. Photoablation: here laser in the far ultraviolet wavelength (350 nm) is used. this model aims to provide the results for temperature distribution evolution inside the human eye, exposed to several laser wavelengths, 193 nm arf excimer laser, 694.3 nm ruby laser, and 1064 nm.