الفهرس 
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Abstract
In 1967 Charles Kelman introduced the technique that uses ultrasonic waves to emulsify the nucleus of the eye’s lens to remove the cataracts without a large incision. It has helped 100 million people nation-wide.
Phacoemulsification uses an ultrasonically driven tip to fragment the nucleus of the cataract and to emulsify these fragments. The technique also uses a surgeon-controlled automated aspiration system to remove the cortical material through a small needle introduced through a very small incision. Phacoemulsification results in a lower incidence of wound related complications, faster healing, and more rapid visual rehabilitation than procedures that require larger incisions. This technique also creates a relatively closed system during both phacoemulsification and aspiration, thereby controlling anterior chamber depth and providing safeguards against positive vitreous pressure and choroidal hemorrhage.
Phacoemulsification complications include posterior capsule tear, zonular dehiscence, iris trauma, hyphaema, vitrous loss, nucleus loss, and bullous keratopathy. Incision problems include short corneal tunnel, wound burn, and wound leak. The ultrasound power necessary for phacoemulsification in routine cataract surgery induces an endothelial cell density loss of 6.3% to 12.8%.Therefore; decreasing ultrasound energy has become a primary goal in cataract surgery, especially in patients with a compromised cornea.
New-generation phaco machines like that using The Ozil Torsional Phacoemulsification Technology and the Ellips technology have emerged to increase the efficiency of removing the nuclear material, and to decrease the rate of corneal endothelial damage and wound tunnel burns.
A femtosecond laser is a laser which emits optical pulses with a duration well below 1 ps (→ ultrashort pulses), i.e., in the domain of femtoseconds (1 fs = 10−15 s). It thus also belongs to the category of ultrafast lasers or ultrashort pulse lasers. Femtosecond laser–induced optical breakdown requires very low energy and produces virtually no thermal damage or shockwave transmission to surrounding tissue.
Femtosecond laser technology in cataract surgery has the potential to provide a high-resolution image of the eye that can drive the precise guidance of the laser, create all of the required refractive corneal incisions, including the entry wound and sideport incision with perfect dimensions as designed by the surgeon, provide a refractive solution to preexisting astigmatism by creating corneal incisions of precise shape and depth as programmed by the surgeon. also it can create a perfectly centered capsulotomy with the optimal refractive dimension or shape for premium IOLs (ie, today’s accommodating lenses and complex designs of the future) and liquefy, soften, or chop the lens.
There is a wealth of information at surgeons’ fingertips regarding the benefits of laser cataract surgery and its potential to revolutionize lens-based procedures. Practitioners who have used the technology agree that laser cataract surgery may move patients closer to the goal of spectacle independence.