Table of Contents
Introduction:
FLACS (Laser-assisted cataract surgery) is one of the most important methods by which most of the knowledge is obtained about the world of sight, which relies on the cornea and lens of the eye to focus light on the retina. The lens is a clear, circumferential structure inside the eye, and it has a central role to play in the whole process of refracting light. It is more sensitive to the unavoidable truth that even tiny changes in shape or degree can bring about vision impairment. It is a biconvex structure placed behind the colored part of the eye known as the iris and in the form of a gelatinous substance called a vitreous body, which is held in place by structures known as the zonules. It has three layers: the outer capsule, a layer of cells, and the inner fibers; it is not innervated and lacks blood supply.
What Are the Common Causes of Cataracts and Its Effect on Vision?
Cataracts are the most common eye disease globally and the leading cause of blindness. In the United States, they are the third most common cause of preventable blindness and often the main reason people report having vision problems. Over eight million doctor visits yearly are due to vision issues caused by cataracts.
A cataract occurs when clumps of protein or yellow-brown pigment build up in the eye's lens, blocking light from reaching the retina. This can cause the lens to become cloudy, which leads to vision problems. For a cataract to be considered significant, it must noticeably reduce vision or impair daily activities. Common symptoms include faded colors, blurry vision, seeing halos around lights, difficulty with bright lights, and trouble seeing at night. While cataracts are usually related to aging, they can also be caused by diabetes, certain medications, UV radiation, smoking, alcohol, and poor nutrition.
There are three main types of cataracts:
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Nuclear.
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Cortical.
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Posterior subcapsular.
To determine the severity of a cataract, doctors typically use a slit lamp to inspect the eye and assign a numerical value visually. Several grading systems, such as:
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Oxford Clinical Cataract Classification and Grading System.
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Lens Opacity Classification System.
These are used in studies to measure cataract severity. Most people over 60 develop cataracts to some degree. The decision to treat cataracts depends on how much they affect a person's vision. If the cataract is not too severe, surgery might not be necessary. However, surgery is usually the only way to restore vision when cataracts significantly impair sight. Cataract surgery involves removing and replacing the cloudy lens with an artificial intraocular lens (IOL).
Phacoemulsification (or phaco): The most common surgical technique used in the U.S. is phacoemulsification (or phaco). This procedure uses an ultrasonic probe to break up the cataract, which suction removes. The artificial lens is inserted into the eye through a small incision. After surgery, patients are typically advised to use anti-inflammatory eye drops for a few weeks. Most people recover within a week, with complete recovery taking about a month. Cataract surgery is highly successful and the most common eye surgery worldwide, with around 19.5 million procedures performed in 2011.
Femtosecond-Laser-Assisted Cataract Surgery: A newer technique, femtosecond-laser-assisted cataract surgery, was first proposed in 1992. This method uses ultrashort laser pulses to remove cataracts. The laser makes precise cuts in the lens tissue, stacked in layers. The tissue is then fragmented and liquified, making it easier to remove.
What Is Femtosecond-Laser-Assisted Cataract Surgery and Its Uses?
FLACS is the next-generation technique where the traditional use of blades and hooks is replaced by ultrashort laser pulses. The application of femtosecond lasers in ophthalmology was originally discussed in 1992 because of the perspectives of ultrashort laser pulses for cataract surgery. Another clinical experiment was made under FDA (food and drug administration) regulation at the University of Saint Louis to forge efficient femtosecond laser technologies for cataract surgery.
Indication:
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Treating wounds.
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Making small, curved cuts in the cornea.
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Creating openings in the front part of the eye’s lens capsule.
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Breaking up the central part of the eye’s lens.
Development and Commercialization:
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Femtosecond lasers have pulse durations of only up to a few hundred femtoseconds to remove a part of the eye with less harm to the surrounding tissue.
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It has advanced with time, and important milestones were reached in 1980 with the introduction of Chirped Pulse Amplification (CPA). CPA plays an important role because it makes it possible to amplify femtosecond laser pulses to the energy required for procedures such as LASIK and cataract surgery.
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The first commercial femtosecond laser system for cataract surgery, LenSx, by Alcon Laboratories Inc., was launched in 2008. The femtosecond laser has been demonstrated to reproduce the traditional cataract surgery parameters in ex vivo porcine eyes by performing surgical actions such as nuclear fragmentation, posterior capsulotomy, and lens fragmentation or emulsification.
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Femtosecond lasers became popular after they were approved by the Food and Drug Administration in 2010 because of their precision in cataract surgery. The mediation helps augment important stages in the procedure, such as corneal incisions, capsulotomy, and the way the lens is broken into fragments, which enhances the surgical results.
Key Components and Technology: The ophthalmic femtosecond lasers solid-state lasers with the lasers gain media such as:
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Neodymium –doped glass.
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Yttrium Aluminium Garnet (Nd:YAG) or others.
They are accompanied by high-resolution focusing and scanning equipment, frequently controlled by Optical Coherence Tomography (OCT). OCT was first used in 1991, and it displays cross-sectional imagery that is important in planning and executing surgery with femtosecond lasers.
Clinical Applications and Advancements:
In addition to being used in the laboratories, femtosecond laser systems are incorporated in operative devices to enhance the precision of cataract operations. These systems consist of pre-operative planning based on images, intra-operative modification of the implants and targets, and exact control of the laser cutting of the target tissue. The success of FLACS is partly because the technique allows minute dissection of capsulotomies and fragment lenses without affecting the adjacent tissues. There are several femtosecond laser commercial systems:
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LenSx.
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Catalys.
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LensAR.
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Victus.
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Femto LDV
Some have different dockings, imaging subsystems, and other variants for various purposes.
Advantages:
Using a femtosecond laser in cataract surgery has several key advantages. It allows surgeons to make exact incisions on the eye's surface. This laser also creates round and centered openings in the eye's lens capsule, which proves more effective in breaking down hard cataracts.
Disadvantages:
Using a femtosecond laser in cataract surgery includes a high price of the laser and single-use items required for the surgery. There are specific risks of complications during the procedure, which lead to pupil shrinkage with this method, and the procedure is also time-consuming.
Conclusion:
Femtosecond-laser-assisted cataract surgery is a revolution in cataract treatment that combines the laser with imaging systems. Since FLACS can improve accuracy, minimize complications, and even mechanize some important steps in such procedures, it will remain relevant in the future of cataract surgery and, more broadly, ophthalmologic surgery.
