IntraLASIK
Encyclopedia
IntraLASIK, also known as Femto-LASIK or All-Laser LASIK, is a form of refractive eye surgery
similar to LASIK
that creates a cornea
l flap with a femtosecond laser
microkeratome
rather than with a mechanical microkeratome, which uses a steel blade. The only difference between LASIK and IntraLASIK is the method by which the LASIK flap is created. The actual refractive correction by cornea
l ablation can then be performed with any excimer
laser that is able to perform LASIK, including conventional, wavefront-optimized, or wavefront-guided ablation. IntraLASIK can be used to surgically create monovision to enhance the ability to see objects both distant and near for those affected by presbyopia
.
The term IntraLASIK is derived from IntraLase
, the name of the first manufacturer to achieve Food and Drug Administration approval of a femtosecond laser for use in the United States, and the surgical procedure 'LASIK'. Although additional femtosecond laser manufacturers have entered the US market, the name IntraLASIK is commonly used.
Contradictory information exists as to whether the use of femtosecond lasers in LASIK achieves statistically better visual acuity
and refractive
outcomes than with microkeratomes.
Although the final long-term clinical outcome of LASIK with a mechanical microkeratome and IntraLASIK with a femtosecond laser may be similar, the increased accuracy of the flap with the femtosecond laser provides an added margin of safety. LASIK with a flap that is thinner has been shown to provide outcomes superior than a thicker LASIK flap. A thinner LASIK flap requires greater accuracy and predictability.
for a period of weeks, however normally resolves with healing and treatment.
eye surgery
technology that is one of several possible alternatives to LASIK
now under investigation. Lower-energy femtosecond lasers may improve upon the traditional excimer laser by reducing disruption of ocular structures, with intrastromal ablation obviating the need for the damaging epithelial incision and ablation currently employed in LASIK and PRK
procedures.
First clinical results were obtained in 2003, and several different techniques are now under investigation, including both ISPRK (intrastromal PRK), and more ambitious wavefront variants. It is believed that intrastromal techniques may eventually increase predictability and repeatability of wavefront ablation. Both 20/10 PERFECT VISION and IntraLase
are known to be sponsoring FLIVC studies using their respective lasers.
Refractive surgery
Refractive eye surgery is any eye surgery used to improve the refractive state of the eye and decrease or eliminate dependency on glasses or contact lenses. This can include various methods of surgical remodeling of the cornea or cataract surgery. The most common methods today use excimer lasers to...
similar to LASIK
LASIK
LASIK or Lasik , commonly referred to simply as laser eye surgery, is a type of refractive surgery for correcting myopia, hyperopia, and astigmatism...
that creates a cornea
Cornea
The cornea is the transparent front part of the eye that covers the iris, pupil, and anterior chamber. Together with the lens, the cornea refracts light, with the cornea accounting for approximately two-thirds of the eye's total optical power. In humans, the refractive power of the cornea is...
l flap with a femtosecond laser
Laser
A laser is a device that emits light through a process of optical amplification based on the stimulated emission of photons. The term "laser" originated as an acronym for Light Amplification by Stimulated Emission of Radiation...
microkeratome
Microkeratome
A microkeratome is a precision surgical instrument with an oscillating blade designed for creating the corneal flap in LASIK or ALK surgery. The normal human cornea varies from around 500 to 600 micrometres in thickness; and in the LASIK procedure, the microkeratome creates a 83 to 200 micrometre...
rather than with a mechanical microkeratome, which uses a steel blade. The only difference between LASIK and IntraLASIK is the method by which the LASIK flap is created. The actual refractive correction by cornea
Cornea
The cornea is the transparent front part of the eye that covers the iris, pupil, and anterior chamber. Together with the lens, the cornea refracts light, with the cornea accounting for approximately two-thirds of the eye's total optical power. In humans, the refractive power of the cornea is...
l ablation can then be performed with any excimer
Excimer
An excimer is a short-lived dimeric or heterodimeric molecule formed from two species, at least one of which is in an electronic excited state. Excimers are often diatomic and are composed of two atoms or molecules that would not bond if both were in the ground state. The lifetime of an excimer is...
laser that is able to perform LASIK, including conventional, wavefront-optimized, or wavefront-guided ablation. IntraLASIK can be used to surgically create monovision to enhance the ability to see objects both distant and near for those affected by presbyopia
Presbyopia
Presbyopia is a condition where the eye exhibits a progressively diminished ability to focus on near objects with age. Presbyopia’s exact mechanisms are not known with certainty; the research evidence most strongly supports a loss of elasticity of the crystalline lens, although changes in the...
.
History
Intelligence Surgical Laser (ISL) approached Arturo S. Chayet M.D. (Mexico) in 1994 with the idea of using a picosecond laser as an alternative to the excimer laser for the correction of refractive errors. Soon enough, however, after a series of clinical trials, Chayet concluded that the picosecond laser was not well suited for refractive corrections, but rather for the creation of corneal flaps, which at the time were created with the mechanical microkeratome (Chayet is credited with the conception of Intralasik). The creation of the corneal flap with the picosecond laser, in conjunction with the use of the excimer laser for the corneal ablation, was the first step to creating a spin-off of LASIK. Researchers at the University of Michigan, however, realized that the picosecond laser was inadequate for Chayet's idea and discovered that the femtosecond laser would work more effectively. In 2000, a corneal flap created by the femtosecond laser along with a refractive error corrected by the excimer laser was conducted on a patient for the first time, in which case Intralasik or All Laser LASIK was conducted for the first time.The term IntraLASIK is derived from IntraLase
IntraLase
IntraLase was a company based in Irvine, California, producing lasers for the medical industry and for eye surgery. In March 2007 it was acquired by Advanced Medical Optics for $800 million in cash. Advanced Medical Optics was acquired by Abbott Laboratories in February 2009...
, the name of the first manufacturer to achieve Food and Drug Administration approval of a femtosecond laser for use in the United States, and the surgical procedure 'LASIK'. Although additional femtosecond laser manufacturers have entered the US market, the name IntraLASIK is commonly used.
Procedure
The computer-guided infrared femtosecond laser is focused just below the surface of the cornea. Each laser pulse creates a tiny bubble there. A pattern of many overlapping bubbles is created, allowing to lift off a flap off the cornea. The procedure then continues as in traditional LASIK, with an excimer laser removing material from the exposed surface beneath the flap.Claimed advantages
A LASIK flap created with a femtosecond laser is regarded by many ophthalmologists as an improvement over traditional LASIK because of a greater accuracy in flap size, shape, and thickness.Contradictory information exists as to whether the use of femtosecond lasers in LASIK achieves statistically better visual acuity
Visual acuity
Visual acuity is acuteness or clearness of vision, which is dependent on the sharpness of the retinal focus within the eye and the sensitivity of the interpretative faculty of the brain....
and refractive
Refractive error
A refractive error, or refraction error, is an error in the focusing of light by the eye and a frequent reason for reduced visual acuity.-Classification:...
outcomes than with microkeratomes.
Although the final long-term clinical outcome of LASIK with a mechanical microkeratome and IntraLASIK with a femtosecond laser may be similar, the increased accuracy of the flap with the femtosecond laser provides an added margin of safety. LASIK with a flap that is thinner has been shown to provide outcomes superior than a thicker LASIK flap. A thinner LASIK flap requires greater accuracy and predictability.
Complications
A small percentage of IntraLASIK patients develop Transient Light Sensitivity (TLS) which causes severe photophobiaPhotophobia
Photophobia is a symptom of abnormal intolerance to visual perception of light. As a medical symptom photophobia is not a morbid fear or phobia, but an experience of discomfort or pain to the eyes due to light exposure or by presence of actual physical photosensitivity of the eyes, though the term...
for a period of weeks, however normally resolves with healing and treatment.
Alternatives
An alternative to IntraLasik, femtosecond laser intrastromal vision correction, is a laserLaser
A laser is a device that emits light through a process of optical amplification based on the stimulated emission of photons. The term "laser" originated as an acronym for Light Amplification by Stimulated Emission of Radiation...
eye surgery
Eye surgery
Eye surgery, also known as orogolomistician surgery or ocular surgery, is surgery performed on the eye or its adnexa, typically by an ophthalmologist.-Preparation and precautions:...
technology that is one of several possible alternatives to LASIK
LASIK
LASIK or Lasik , commonly referred to simply as laser eye surgery, is a type of refractive surgery for correcting myopia, hyperopia, and astigmatism...
now under investigation. Lower-energy femtosecond lasers may improve upon the traditional excimer laser by reducing disruption of ocular structures, with intrastromal ablation obviating the need for the damaging epithelial incision and ablation currently employed in LASIK and PRK
Photorefractive keratectomy
Photorefractive keratectomy and Laser-Assisted Sub-Epithelial Keratectomy are laser eye surgery procedures intended to correct a person's vision, reducing dependency on glasses or contact lenses. The first PRK procedure was performed in 1987 by Dr. Theo Seiler, then at the Free University...
procedures.
First clinical results were obtained in 2003, and several different techniques are now under investigation, including both ISPRK (intrastromal PRK), and more ambitious wavefront variants. It is believed that intrastromal techniques may eventually increase predictability and repeatability of wavefront ablation. Both 20/10 PERFECT VISION and IntraLase
IntraLase
IntraLase was a company based in Irvine, California, producing lasers for the medical industry and for eye surgery. In March 2007 it was acquired by Advanced Medical Optics for $800 million in cash. Advanced Medical Optics was acquired by Abbott Laboratories in February 2009...
are known to be sponsoring FLIVC studies using their respective lasers.
See also
- Eye surgeryEye surgeryEye surgery, also known as orogolomistician surgery or ocular surgery, is surgery performed on the eye or its adnexa, typically by an ophthalmologist.-Preparation and precautions:...
- IntraLaseIntraLaseIntraLase was a company based in Irvine, California, producing lasers for the medical industry and for eye surgery. In March 2007 it was acquired by Advanced Medical Optics for $800 million in cash. Advanced Medical Optics was acquired by Abbott Laboratories in February 2009...
- Femtosecond Laser Intrastromal Vision Correction
- Bates method Bates MethodThe Bates method is an alternative therapy aimed at improving eyesight. Eye-care physician William Horatio Bates attributed nearly all sight problems to habitual strain of the eyes, and felt that glasses were harmful and never necessary...