KIDS NEED SHADE, TOO

Image

KIDS NEED SHADE, TOO

Children’s eyes don’t filter light as well as adults’ so damage to their eyes can start early, especially since most children spend significantly more time outdoors than adults.

Sunglasses for kids shouldn’t be treated as a novelty item! Instead buy quality shades that offer 100 percent UV protection.

Polycarbonate or Trivex lenses work best on little peepers because they are virtually shatter-resistant and completely block damaging UV rays.

Visit Dr. Landrio’s office for a selection of kid-appropriate styles, sizes and price range.

WAVE-GUIDED LASER VISION CORRECTION

Wavefront-guided LASIK is a variation of LASIK surgery in which, rather than applying a simple correction of focusing power to the cornea (as in traditional LASIK), an ophthalmologistapplies a spatially varying correction, guiding the computer-controlled excimer laser with measurements from a wavefront sensor. The goal is to achieve a more optically perfect eye, though the final result still depends on the physician’s success at predicting changes that occur during healing and other factors that may have to do with the regularity/irregularity of the cornea and the axis of any residual astigmatism. In older patients, scattering from microscopic particles (cataract or incipient cataract) may play a role that outweighs any benefit from wavefront correction. Therefore, patients expecting so-called “super vision” from such procedures may be disappointed.

Australian ophthalmologist Noel A. Alpins, who developed a vector analysis method to analyze astigmatism in cataract, refractive, and corneal surgery, has long advocated combining “vector planning” with wavefront-guided LASIK. Alpins’ contention is that the purely refraction-based approach represented by wavefront analysis contradicts corneal surgical experience developed over many years. Refractive surgeons have long known that corneal regularity is the foundation of superior visual outcomes. Because refractive and corneal topographic astigmatism do not always align, corrections for internal optical errors surgically sculpted onto the cornea may increase corneal irregularity.Alpins believes that the pathway to “super vision” requires a greater customized reduction of corneal astigmatism than is usually attempted, and that any remaining astigmatism ought to be regular (as opposed to irregular), which are both fundamental principles of vector planning overlooked by a purely wavefront-guided treatment plan. Alpins’ observation was confirmed in a prospective study of LASIK patients, which found a greater reduction in corneal astigmatism and better visual outcomes under mesopic conditions using wavefront technology combined with vector analysis (the Alpins method) than using wavefront technology alone, and also found equivalent higher-order aberrations.

No good data can be found that compare the percentage of LASIK procedures that employ wavefront guidance versus the percentage that do not, nor the percentage of refractive surgeons who have a preference one way or the other. Wavefront technology continues to be positioned as an “advance” in LASIK with putative advantages; however, it is clear that not all LASIK procedures are performed with wavefront guidance.

Still, surgeons claim patients are generally more satisfied with this technique than with previous methods, particularly regarding lowered incidence of “halos,” the visual artifact caused byspherical aberration induced in the eye by earlier methods. A meta-analysis of eight trials showed a lower incidence of these higher order aberrations in patients who had wavefront-guided LASIK compared to non-wavefront-guided LASIK. Based on their experience, the United States Air Force has described WFG-Lasik as giving “superior vision results”.

What to expect during Lasik

Operative procedure

Flap creation:

Once the eye is immobilized, the flap is created. This process is achieved by using a femtosecond laser that creates a series of tiny closely arranged bubbles within the cornea.  A hinge is left at one end of this flap. The flap is folded back, revealing the stroma, the middle section of the cornea. The process of lifting and folding back the flap can sometimes be uncomfortable.

 

Laser remodelling:

The second step of the procedure uses an excimer laser (193 nm) to remodel the corneal stroma. The laser vaporizes the tissue in a finely controlled manner without damaging the adjacent stroma. No burning with heat or actual cutting is required to ablate the tissue. The layers of tissue removed are tens of micrometres thick. Performing the laser ablation in the deeper corneal stroma provides for more rapid visual recovery and less pain than the earlier technique, photorefractive keratectomy (PRK). During the second step, the patient’s vision becomes blurry, once the flap is lifted.  The excimer laser uses an eye tracking system that follows the patient’s eye position up to 4,000 times per second, redirecting laser pulses for precise placement within the treatment zone. Typical pulses are around 1 millijoule (mJ) of pulse energy in 10 to 20 nanoseconds.[23]

 

Repositioning of the flap:

After the laser has reshaped the stromal layer, the LASIK flap is carefully repositioned over the treatment area by the surgeon and checked for the presence of air bubbles, debris, and proper fit on the eye. The flap remains in position by natural adhesion until healing is completed.

COURAGE AND DETERMINATION

Tiger Eye or Tiger’s Eye is an iridescent gemstone. The name itself means a significance characteristic of a tiger. A tiger is known to be focused, has strong determination and it is patient. A tiger concentrates on its desires. He longs to attain it no matter how high the destination it may be. Its determination never ceases that it can pursue almost impossible dreams. Its patience adds to its significant characteristic. A tiger will really wait even if an opportunity takes days to come.
 
Hence, wearing this gemstone, one can acquire these characteristics. When one waits patiently, he can reach his goal at the right time. With correct focus, one can also achieve what he is longing for in life. Apart from the two, determination is necessary as there will be challenges along the way. But with determination, one will surely succeed.
 
 
Therapeutic Properties 
The wearer of Tiger Eye can attract good fortune. Apart from this, it is also a famous gem that restores balance and provides therapeutic touch. It has an excellent ability to heal individuals who are suffering from their emotions, anxious and unstable state of being, those who are in fear and worries, clouded and confused mind, depressed people, and those who have ADD.
 
With its presence, it can draw courage and power to fight any negative energy. The wearer will be able to see clearly what is needed for him to act with confidence and without being illusionary with life’s realities. It can also pacify one’s heart and this brings a sense of healthy well being. Also, harmony is restored in one’s mind, body and spirit.
 

PRE-OPERATIVE STEPS IN LASER VISION CORRECTION

The procedure involves creating a thin flap on the eye, folding it to enable remodeling of the tissue beneath with a laser and repositioning the flap.

PRE-OPERATIVE PROCEDURES AND CONTACT LENSES

Patients wearing soft contact lenses are instructed to stop wearing them 5 to 21 days before surgery. One industry body recommends that patients wearing hard contact lenses should stop wearing them for a minimum of six weeks plus another six weeks for every three years the hard contacts have been worn.[20] The cornea is avascular because it must be transparent to function normally. Its cells absorb oxygen from the tear film. Thus, low-oxygen-permeable contact lenses reduce the cornea’s oxygen absorption, sometimes resulting in corneal neovascularization—the growth of blood vessels into the cornea. This causes a slight lengthening of inflammation duration and healing time and some pain during surgery, because of greater bleeding. Although some contact lenses (notably modern RGP and soft silicone hydrogel lenses) are made of materials with greater oxygen permeability that help reduce the risk of corneal neovascularization, patients considering LASIK are warned to avoid over-wearing their contact lenses. Usually, it is recommended that they discontinue wearing contact lenses days or weeks before the LASIK eye surgery.

PRE-OPERATIVE PROCEDURES TO HELP DETERMINE CANDIDACY:

In the USA, the FDA has approved LASIK for age 18 and over.[21] More importantly the patient’s eye prescription should be stable for at least one year prior to surgery. The patient may be examined with pupillary dilation and education given prior to the procedure. Before the surgery, the patient’s corneas are examined with a pachymeter to determine their thickness, and with a topographer, or corneal topography machine,[1] to measure their surface contour. Using low-power lasers, a topographer creates a topographic map of the cornea. The procedure is contraindicated if the topographer finds difficulties such as keratoconus[1] The preparatory process also detects astigmatism and other irregularities in the shape of the cornea. Using this information, the surgeon calculates the amount and the location of corneal tissue to be removed. The patient is prescribed and self-administers an antibiotic beforehand to minimize the risk of infection after the procedure and is sometimes offered a short acting oral sedative medication as a pre-medication. Prior to the procedure, anaesthetic eye drops are instilled.

 

 

INTRODUCTION OF LASIK

Patent

On 20 June 1989, Gholam A. Peyman was granted a US patent for LASIK (US4840175). It was,

“A method and apparatus for modifying the curvature of a live cornea via use of an excimer laser. The live cornea has a thin layer removed therefrom, leaving an exposed internal surface thereon. Then, either the surface or thin layer is exposed to the laser beam along a predetermined pattern to ablate desired portions. The thin layer is then replaced onto the surface. Ablating a central area of the surface or thin layer makes the cornea less curved, while ablating an annular area spaced from the center of the surface or layer makes the cornea more curved. The desired predetermined pattern is formed by use of a variable diaphragm, a rotating orifice of variable size, a movable mirror or a movable fiber optic cable through which the laser beam is directed towards the exposed internal surface or removed thin layer.”[13]
Implementation in USA

The LASIK technique was implemented in the USA after its successful application elsewhere. The Food and Drug Administration (FDA) commenced a trial of the excimer laser in 1989. The first enterprise to receive FDA approval to use an excimer laser for photo-refractive keratectomy was Summit Technology (founder and CEO, Dr. David Muller).[14] In 1992, under the direction of the FDA, Pallikaris introduced LASIK to ten VISX centres. In 1998, the “Kremer Excimer Laser”, serial number KEA 940202, received FDA approval for its singular use for performing LASIK.[15] Subsequently, Summit Technology was the first company to receive FDA approval to mass manufacture and distribute excimer lasers. VISX and other companies followed.[15]

The excimer laser that was used for the first LASIK surgeries by I.Pallikaris

Pallikaris suggested a flap of cornea could be raised by microkeratome prior to the performing of PRK with the excimer laser. The addition of a flap to PRK became known as LASIK.

Further developments

Since 1991, there have been further developments such as faster lasers; larger spot areas; bladeless flap incisions; intraoperative corneal pachymetry; and “wavefront-optimized” and “wavefront-guided” techniques. However, use of the excimer laser risks damage to the retina and optic nerve. The goal of refractive surgery is to avoid permanently weakening the cornea with incisions and to deliver less energy to the surrounding tissues.